Freeze resistant watering nipple device

Abstract

A freeze-resistant watering nipple assembly comprising a watering nipple valve, a heat pipe, a sleeve in tight thermal contact with the nipple, a water-tight connection to a liquid containing container or supply pipe, and an outer shield enclosing an insulating space and/or insulation material is described, which thermally couples a watering nipple to a container or supply pipe via a sufficiently good thermal conduction path so that the nipple can be maintained at a temperature that is near the temperature of the liquid in the container or supply pipe. Further, the use of one or more freeze-resistant watering nipple assemblies with a thermally insulated container is described so that the unit comprising the nipple assembly or assemblies and the insulated container provides drinking water to animals, and in particular, birds in sub-freezing and in hot weather.

Claims

1. A nipple valve device for providing drinking water or liquid to animals, birds, or poultry, said device comprising: a heat pipe in contact with the water or liquid in a container or supply pipe; a water-tight connection to the container or supply pipe by which the heat pipe protrudes from the container or supply pipe; a nipple valve having a body, an actuator, and an exit surface; a clamped sleeve in tight thermal contact with said nipple valve; an outer shield enclosing said sleeve and said nipple valve therein; and, wherein said heat pipe is in thermal contact with said sleeve that is in thermal contact with the body of said nipple valve, and said actuator and said exit surface expose through said outer shield for use by the animals, birds, or poultry.

2. The nipple valve device of claim 1 further comprising: said sleeve integrating with said heat pipe.

3. The nipple valve device of claim 1 further comprising: said nipple valve joining to one of said heat pipe by a water-tight connection or said sleeve by a water-tight connection wherein said sleeve joins to said heat pipe by a water-tight connection or wherein said sleeve integrates with said heat pipe.

4. A nipple valve device for providing drinking water or liquid to animals, birds, or poultry, said device comprising: a heat pipe in contact with the water or liquid in a container or supply pipe; a water-tight connection to the container or supply pipe by which the heat pipe protrudes from the container or supply pipe; a nipple valve having a body, an actuator, and an exit surface; a sleeve in tight thermal contact with said nipple valve; an outer shield enclosing said sleeve and said nipple valve therein; wherein said heat pipe is in thermal contact with said sleeve that is in thermal contact with the body of said nipple valve, and said actuator and, said exit surface expose through said outer shield for use by the animals, birds, or poultry; a thermally conductive metal annular ring connecting said sleeve to said nipple valve proximate said exposed face and said actuator; and said thermally conductive metal annular ring being made of aluminum, copper, brass, bronze, silver, stainless steel, platinum group metal, combinations thereof, or alloys thereof.

5. The nipple valve device of claim 1 wherein said clamped sleeve is made of copper, brass, aluminum, silver, annealed copper, or alloys thereof.

6. The nipple valve device of claim 1 wherein said heat pipe is made of copper, brass, aluminum, silver, or alloys thereof.

7. The nipple valve device of claim 6 wherein said heat pipe has either a coating or a plating thereon so that said heat pipe resists corrosion and release of metal ions into the water in the container or supply pipe.

8. The nipple valve device of claim 7 wherein said heat pipe is an aluminum tube that has an anodized coating.

9. The nipple valve device of claim 1 further comprising: one or more wire hoops holding said clamped sleeve.

10. The nipple valve device of claim 9 further comprising: said one or more wire hoops being made of stainless steel, each of said wire hoops having a loop of wire with two ends mutually twisted wherein each of said wire hoops contract inwardly causing pressure promoting efficient thermal contact between said sleeve and said nipple valve.

11. A nipple valve device for providing drinking water or liquid to animals, birds, or poultry, said device comprising: a heat pipe in contact with the water or liquid in a container or supply pipe; a water-tight connection to the container or supply pipe by which the heat pipe protrudes from the container or supply pipe; a nipple valve having a body, an actuator, and an exit surface; a sleeve in tight thermal contact with said nipple valve; an outer shield enclosing said sleeve and said nipple valve therein; wherein said heat pipe is in thermal contact with said sleeve that is in thermal contact with the body of said nipple valve, and said actuator and said exit surface expose through said outer shield for use by the animals, birds, or poultry; and, insulation surrounding said sleeve and said nipple valve, said insulation locating within said outer shield.

12. The nipple valve device of claim 11 further comprising: said insulation having at least one of a metal reflective foil, metalized film, a coating, or an air gap to reduce radiative transport of heat.

13. A waterer for providing drinking water or liquid to animals, birds, and poultry, said waterer comprising: an insulated container; at least one freeze-resistant nipple valve device, said nipple valve device comprising: a heat pipe in contact with the water or liquid in the container, said heat pipe having a water-tight connection to said container or to a supply pipe, said heat pipe protruding from the container; a nipple valve having a body, an actuator, and an exit surface; a sleeve in tight thermal contact with said nipple valve; an outer shield; said heat pipe having thermal contact with said sleeve in thermal contact with said body of said nipple valve; said outer shield enclosing said sleeve and said nipple valve; wherein said actuator and said exit surface of said nipple expose through said outer shield for use by the animals, birds, and poultry; and, said insulated container having an inner bucket and an outer bucket, insulation surrounding the inner bucket, and at least one removable lid.

14. The waterer of claim 13 wherein said inner bucket and said nipple valve device separate from said outer bucket.

15. The waterer of claim 13 wherein said water tight connection of said heat pipe and said insulated container is an elastomer grommet.

16. The waterer of claim 13 further comprising: said insulated container having insulation at least one of polymer foam, bubble sheet, metal reflective foil, metalized film, or coating to reduce radiative transport of heat.

17. The waterer of claim 13 wherein said waterer can be filled with warm water of a temperature of 105 degrees F. or less and will provide liquid water for at least 8 hours when said waterer is within an environment of a temperature of at least 0 degrees F. and wherein said waterer can be filled with cool water of a temperature in the range of 32 to 40 degrees F. and will provide water with temperature less than 90 degrees F. for at least 8 hours when said waterer is within an environment of a temperature at or below 110 degrees F.

18. The waterer of claim 13 further comprising: an immersion heater of about 15 to about 17 watts per gallon of volume of said inner bucket, said immersion heater maintaining water within said container at a temperature in a range of 50 to 80 degrees F., and said waterer delivering water at a temperature greater than 40 degrees F. when said waterer is within an environment of a temperature of more than 10 degrees F.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In referring to the drawings,

(2) FIG. 1 shows a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(3) FIG. 2 shows a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(4) FIG. 3 shows a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(5) FIG. 4 shows a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(6) FIG. 5 shows a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(7) FIG. 6 provides a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(8) FIG. 7 provides a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(9) FIG. 8 provides a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe;

(10) FIG. 9 provides a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe wherein the feed-through connection has a rubber or elastomer grommet;

(11) FIG. 10a provides a sectional view on a vertical plane of an embodiment of a freeze-resistant nipple valve device with a heat pipe, sleeve, mounting and feed-through connection to a container or supply pipe wherein the feed-through connection has a rubber or elastomer grommet, and FIG. 10b provides an end view of the bottom of the freeze-resistant nipple assembly 5;

(12) FIG. 11a describes as a sectional view on a vertical plane of the embodiment shown in FIG. 10 including two detail views of a horizontal cross-section, the detail view on the lower left, FIG. 11b is shown in the same scale as the vertical plane cross-section view in the upper left, and the view to the right, FIG. 11c is the horizontal plane cross-section view magnified two fold;

(13) FIG. 12 describes a side view of an embodiment of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device with a heat pipe, a sleeve, a mounting and feed-through connection, and an outer shield;

(14) FIG. 13 describes a side view of a reveal of an embodiment of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device with a heat pipe, a sleeve, a mounting and feed-through connection, and an outer shield, wherein the principal interior parts are shown as dashed lines;

(15) FIG. 14 describes a top view of an embodiment of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device with a heat pipe, a sleeve, a mounting and feed-through connection, and an outer shield;

(16) FIG. 15 describes a bottom view of an embodiment of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device 5 with a heat pipe, a sleeve, a mounting and feed-through connection, and an outer shield 84;

(17) FIG. 16 illustrates a sectional view of an embodiment of a low heat-loss rate waterer with an integrated insulated, shielded, freeze-resistant nipple valve device with a heat pipe, a sleeve, a mounting and feed-through connection, and an outer shield;

(18) FIG. 17 illustrates a chart of the calculated water temperature T (i.e., the reservoir temperature inside of a 2 gallon outer bucket embodiment of the waterer shown in FIGS. 12-15) as a function of time, t where the upper three curves, T vs. t are shown with a heater inside the inner bucket at various power levels and where the lower two curves, T vs t are shown without a heater inside the inner bucket at calculated and experimental power levels; and,

(19) FIG. 18 provides a sectional view on a vertical plane of an alternate embodiment of a freeze-resistant nipple valve device with an actuator closed by a ball.

(20) The same reference numerals refer to the same parts throughout the various figures.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(21) A freeze-resistant nipple valve device 5 of the present invention as shown as various embodiments in FIGS. 1-16, comprises a heat pipe 10, a sleeve 20 in tight thermal contact with a nipple valve 30, a water-tight connection to a container or supply pipe, which may comprise a feed-through of two joined parts being a male part 75 and a female part 76 or of a rubber or elastomer grommet 83, and an outer shield 84 enclosing an insulating air gap space 8 with a reflective heat shield 110 on one of the surfaces defining the air gap space, and/or on or incorporated into insulation material 140 between the said nipple valve 30 and the outer shield 84. The heat conductive sleeve surrounds and is in tight thermal contact with at least a portion of the body of the nipple valve. The outer shield provides protection from exterior ambient cold or hot air.

(22) In one preferred embodiment, the sleeve 20 is a clamped sleeve that has an axial slot 22 to allow radial compression of the sleeve onto the body 36 of the nipple valve 30. In another preferred embodiment, a heat conducting ring 130 having an axial slot 132 may be situated around the nipple valve part comprising a metal annulus with exposed lower surface 32 and within the clamped sleeve 20 to transmit heat to the nipple valve seat. A thermal joint enhancement foil 18 may be used to fill a gap between the heat pipe 10 and the clamped sleeve 20. A thermal joint enhancement foil may also be used to fill a gap between conductive metal ring 130 and clamped heat shield 20. In one preferred embodiment, the joint enhancement foil is a good conducting metal. In one more-preferred embodiment, the good conducting material is aluminum, aluminum alloy, or gold. In another more preferred embodiment, the outer diameter of the heat pipe 10 and the outer diameter of the nipple valve body 36 are matched so that the clamped sleeve 20 can be easily made to conform to both. In one preferred embodiment, the nipple valve body 36 outer diameter, if larger than the outer diameter of the heat pipe 10, is machined as a minor modification to obtain a match. The machining may be by turning, grinding, sanding, filing, or any common method or combination thereof as known in the art. The nipple valve 30 is mounted into the heat pipe 10 and sealed by a polymer or elastomer annular gasket 46, or the nipple valve is screwed into a threaded hole at the lower end of the heat pipe and optionally sealed with threaded joint sealing tape such as Teflon tape, so that the entrance orifice of the nipple is in contact with the liquid, e.g., water, in the interior of the heat pipe 10, and the internal parts of the nipple, for example, an upper stage headed pin 42 or a valve seat weight comprising a sphere 40 or cylindrical disk, are free to move. In the figures, the wall 350 of a reservoir container 50 or a supply pipe wall is represented as the interior surface 100 and an exterior surface 200 that may be enclosed in an outer enclosure 300 that may be a bucket.

(23) The heat pipe 10, the interface 18 between the heat pipe 10 and the clamped sleeve 20, which interface 18 may comprise an optional shim sleeve or wrapping of malleable heat conducting material, the clamped sleeve 20, and the wall of the nipple valve housing 36 in the vicinity of the nipple valve seat comprise a series connected thermal path between the reservoir and the nipple valve 30. Accordingly, the thermal resistance of this path is the sum of the resistance of the heat pipe .sub.p, the resistance of the interface .sub.psc comprising contact resistance(s) and resistance of the optional shim sleeve or wrapping, the resistance of the clamped sleeve .sub.sl, the resistance of the contact interface .sub.c1 between the clamped sleeve and the body 36 of the nipple valve housing, the resistance of the nipple valve housing .sub.w[[k].sub.wD.sub.wl].sup.1, and the resistance of the contact interface .sub.c2 between the housing of the nipple valve housing 36 and the lower metal part with exposed surface 32 and orifice through which an actuator 34 protrudes, here shown as a pin. The Applicants foresee alternate forms of the actuator including a pin, lever, ball, knob, and the like. The body 36 of the nipple valve has thermal conductivity k.sub.w, mean diameter D.sub.w, and thickness . l is the height of the principal part of the metal annulus with exposed surface 32, which is in contact with or is part of the wall of the nipple valve body that is in contact with the clamped sleeve. Thus, .sub.total=.sub.p+.sub.psc+.sub.sl+.sub.c1+.sub.w+.sub.c2.

(24) When the heat pipe 10 or clamped sleeve 20 comprises an annular circular cylinder, the thermal resistance can be calculated by substitution of the appropriate values of the annular cylinder of length L, outer diameter D.sub.2, and inner diameter D.sub.1, and made of material with thermal conductivity k, into Eqn. (1) given as
=4L[k(D.sub.2.sup.2D.sub.1.sup.2)].sup.1.(1)

(25) The temperature difference between the reservoir temperature T.sub.r and the nipple valve seat temperature T.sub.ns is T.sub.ms=T.sub.rT.sub.ns. As a lumped-circuit estimate, for a given radial heat loss along the heat pipe Q.sub.hp, the radial heat loss along the clamped sleeve Q.sub.s, and a heat loss at the exposed lower surface 32 of the nipple valve Q.sub.n, the temperature difference T.sub.ms is the sum of the temperature differences between the reservoir and lower end of the heat pipe T.sub.rp, the temperature difference between the lower end of the heat pipe and the lower end of the clamped sleeve T.sub.ps, and the temperature difference between the lower end of the clamped sleeve and the exposed lower surface of the nipple valve T.sub.ns. Thus, T.sub.ms is given by
T.sub.msT.sub.rp+T.sub.ps+T.sub.sn=Q.sub.hp.sub.p+Q.sub.s.sub.s+Q.sub.n.sub.sn,(2)
where .sub.p is the thermal resistance of the heat pipe, .sub.r=.sub.psc+.sub.sl is the thermal resistance of the clamped sleeve, and .sub.sn=.sub.c1+.sub.w+.sub.c2 is the thermal resistance of the thermal path via the clamped sleeve 20 to the exposed lower surface 32 of the nipple valve 30.

(26) When the series resistance and the losses are sufficiently small, then, by Eqn. 2, T.sub.rns will be sufficiently small so that the nipple valve seat temperature will be within a few degrees of the reservoir temperature.

(27) The thermal losses from the exposed lower surface 32 of the nipple valve 30 and actuator pin 34 principally are the radiated loss and the convection loss. For machined stainless steel surfaces, the emissivity is approximately 0.5. The radiation loss is approximately
P.sub.rn.sub.B(T.sub.ns.sup.4T.sub.0.sup.4)A.sub.n,(3)
where .sub.B is the Stefan-Boltzmann constant. For a typical nipple valve, A.sub.n1.810.sup.4 m.sup.2. Accordingly, P.sub.m0.007 W, when T.sub.ns0 C., and T.sub.018 C.

(28) The convection loss at the exposed nipple valve exposed lower surface 32 can be estimated in the free convection case where there is no wind blowing across the exposed nipple surfaces, and also in the forced convection case where there is a wind of speed v.sub.w. The convective heat transfer coefficient is estimated as

(29) $\begin{array}{cc}h=\mathrm{Nu}{L}_c^{-1}{k}_{a}0.66{\mathrm{Re}}^{\frac{1}{2}}\stackrel{\frac{1}{3}}{\mathrm{Pr}}{k}_a{L}_c^{-1},\left(\mathrm{laminar}\mathrm{flow}\right)& \left(4a\right)\\ h=\mathrm{Nu}{L}_c^{-1}{k}_{a}0.037{\mathrm{Re}}^{\frac{4}{5}}\stackrel{\frac{1}{3}}{\mathrm{Pr}}{k}_a{L}_c^{-1},\left(\mathrm{turbulent}\mathrm{flow}\right)& \left(4b\right)\end{array}$
where k.sub.a is the thermal conductivity of air k.sub.a0.024 and the Prandtl number is Pr0.715 at 0 C., L.sub.c is a characteristic length (L.sub.c0.25 D.sub.shield for laminar flow, D.sub.shield being the outer diameter of the outer shield 84) and Re=.sub.wL.sub.cv.sup.1, and is the kinematic viscosity 1.3310.sup.5 m.sup.2/s at 0 C. When v.sub.w5 mph (2.24 m/s), and L.sub.c0.01 m, Re1684, and the flow is laminar. In this case and by Eqn. (4a), h=17.6 W/m.sup.2K, and Q.sub.nhA.sub.n(T.sub.nsT.sub.0)+P.sub.m0.1 W. If a discontinuity induces a sudden transition to turbulence, then h is given by Eqn. (4b), h=9, and Q.sub.n0.05 W.

(30) In contrast is the heat loss for free convection from a downward facing disk for which
h=NuL.sub.c.sup.1k.sub.a0.27(GrPr).sup.1/4L.sub.c.sup.1k.sub.a,(5)
where Gr is the Grashoff number. For the conditions in the above described example, h12.1 W/m.sup.2 k for free convection versus 17.6 for forced convection. Thus, the heat loss by forced convection because of wind generally is substantially greater than by free convection.

(31) The radial conduction and/or convection loss via the insulation, mounting sleeve 80 or outer shield 84 and/or annular space 8 surrounding the heat pipe 10 and clamped sleeve 20 can be estimated as
Q.sub.hp=Q.sub.cond-hp,(6)
Q.sub.s=Q.sub.ins-sleeve+P.sub.r-sleeve,(7)
where Q.sub.cond-hp is the conduction heat loss of the heat pipe 10 in the vicinity of the feed-through (male part 75 and female part 76 or grommet 83 as later shown in FIG. 9) where the heat pipe 10 passes from the interior 100 of the reservoir container or supply pipe to the exterior 200 of said container or pipe, Q.sub.ins-sleeve is the radial conduction and/or the convection heat loss from the clamped sleeve 20, and P.sub.r-sleeve is the radial radiation heat loss from the clamped sleeve 20 in the case where there is an air gap 8 surrounding the clamped sleeve 20.

(32) The conduction heat loss of the heat pipe 10 in the vicinity of the feed-through (parts 75 and 76 or grommet 83) is small because the temperature difference T.sub.ft between the heat pipe 10 and the walls of the feed through is small. As an estimate, Q.sub.cond-hpk.sub.pA.sub.feed-throughT.sub.ft/.sub.ft, and k.sub.p0.19 is a typical value of thermal conductivity for plastic feed-through parts 75 and 76, gasket 70, or grommet 83, or wall material (for example polyvinyl chloride, PVC), A.sub.feed-through110.sup.3 m.sup.2 is a typical surface area, and .sub.ft0.006 m is a typical radial gasket 70 and wall thickness of parts 75 and 76 or grommet 83, it is seen that Q.sub.cond-hp0.03T.sub.ft. When T.sub.ft5 C., Q.sub.cond-hp0.15 W.

(33) The radial conduction heat loss from a clamped sleeve 20 surrounded by optional insulation 140 and/or 128 is estimated as

(34) $\begin{array}{cc}{Q}_{\mathrm{ins}-\mathrm{sleeve}}2k_{\mathrm{ins}}{L}_{\mathrm{sleeve}}{T_s\left[\ln \left(\frac{d_2}{d_1}\right)\right]}^{-1},& \left(8\right)\end{array}$
where the thermal conductivity of the insulation 140 surrounding the clamped sleeve k.sub.ins may have a typical value 0.06 W/mK (for example, polyethylene small cell foam), L.sub.sleeve is the length of the clamped sleeve (a typical value being about 0.03 m), T.sub.s18 C. for T.sub.ns0 C. and T.sub.018 C., and d.sub.2 and d.sub.1 are the outer diameter and inner diameter of the insulation, respectively. When d.sub.10.015 m and d.sub.20.033, Q.sub.ins-sleeve0.26 W. This is an overestimate when the reservoir container is surrounded by an outer container 300 (as shown in FIG. 12), as only part of the nipple assembly outer shield 84 may be exposed to ambient temperature where the nipple device 5 protrudes outside of the outer container.

(35) Radiation heat loss across the air gap 8 is effectively reduced by use of a reflective heat shield 110 such as may be formed by a cylinder of aluminized polyester (e.g., aluminized Mylar) film. In this case, the emissivity is 0.04, the clamped sleeve area is A.sub.sleeve1.410.sup.3 m.sup.2, and the outer surface of the air gap is at a temperature >T.sub.0. In this case, Eqn. (3) may be used with the substitution of A.sub.sleeve for A.sub.n to estimate the radiation heat loss from the clamped sleeve. For the typical values given, P.sub.r-sleeve0.004 W. Without the reflective heat shield, this loss would be 25 times greater, i.e., 0.1 W.

(36) The sleeve 20 may be surrounded by both an insulating air gap 8 and an annulus of insulating material 140 in addition to the outer shield 84 as shown in FIGS. 2, and 7-11. In this case, the temperature of the interface at the air gap 8 and insulating material 140 depends on the relative radial thickness of the air gap 8 and insulation 140, and the values of convection heat transfer coefficient in the air gap and the thermal conductivity of the insulation material.

(37) As the annulus of insulation material 140 and the annular air gap 8 are series resistances, the heat flux through the insulation material 140 may be equated with the heat flux across the air gap 8, which is the sum of convective flux and radiative flux. With a reflecting heat shield 110 on one of the surfaces defining the air gap 8, and, for the purposes of estimation, assuming that the reflective heat shield 110 is on the surface interface between the air-gap 8 and the insulating material 140, or the heat shield is incorporated into insulation material 140, and that the outer surface of the sleeve 20 is at temperature T.sub.sl=T.sub.rT.sub.rs, and the ambient exterior temperature is T.sub.0, then, the temperature T.sub.i on the surface interface between the air-gap 8 and the insulating material 140 is estimated as

(38) $\begin{array}{cc}{T}_i=\left[\frac{C_0{T}_0+\left(p_r+h_i{A}_{\mathrm{sl}}\right)T_{\mathrm{sl}}}{C_0+p_r+h_i{A}_{\mathrm{sl}}}\right],& \left(9\right)\\ \mathrm{where}& \\ C_0=2k_{\mathrm{ins}}{L_{\mathrm{sleeve}}\left[\ln \left(\frac{d_0}{d_1}\right)\right]}^{-1},& \left(10\right)\\ p_{r}4\mathrm{.Math.}{}_B\left(T_{\mathrm{si}}^2\right)A_{\mathrm{sl}},& \left(11\right)\\ h_i=\mathrm{Nu}{L}_c^{-1}{k}_{a}0.53{\left(\mathrm{GrPr}\right)}^{\frac{1}{4}}{L}_c^{-1}{k}_a,& \left(12\right)\end{array}$
and, in the case where the insulating material 140 surrounds the air gap 8, d.sub.0 is the outer diameter of the insulation annulus, d.sub.1 is the diameter of the interface surface (and the diameter of the annular reflective heat shield 110), and the Grashoff number Gr in Eqn. (12) is estimated for a temperature difference T.sub.slT.sub.0. By Eqns. (9-12), the interface temperature can be calculated, and the radial heat flux estimated as

(39) $\begin{array}{cc}{Q}_{\mathrm{radial}}2k_{\mathrm{ins}}{L_{\mathrm{sleeve}}\left(T_{\mathrm{sl}}-T_0\right)\left[\ln \left(\frac{d_0}{d_1}\right)\right]}^{-1}.& \left(13\right)\end{array}$

(40) One embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through connection to a container or supply pipe, a heat conductive clamped sleeve 20 surrounding the body of a nipple valve 30, an air-gap 8 and reflective heat shield 110 surrounding the nipple valve 30 and sleeve 20, an outer shield 84 that provides protection from exterior ambient cold or hot air is shown in FIG. 1. In one preferred embodiment, the heat pipe 10 is made of good conducting metal that has low susceptibility to corrosion in water or whatever fluids will be put into the reservoir or supply line. Examples of good conducting metal include aluminum and alloys thereof, copper and alloys thereof, brass alloys, noble metals, platinum group metals, and metals and alloys having a thermal conductivity greater than about 90 W/m-K at 0 C. Copper and several copper alloys have thermal conductivity greater than 250 W/m-K at 0 C. Some metals may undergo chemical reactions and release undesirable compounds into the reservoir unless coated or treated to reduce or prevent corrosion. Aluminum has good corrosion resistance in aqueous solutions and water when the pH is between 6 and 8. Outside of this range or to further reduce corrosion, it may be desirable to coat or treat the aluminum, for example with plastic coatings, plating with corrosion resistant metals, or anodization to resist corrosion, and/or other treatments that are known in the art. Similarly, other good conducting metals can be used provided the surfaces are treated to resist corrosion. Other noble metals, e.g., gold and silver, and platinum group metals also can be used for the heat pipe or for plating, but they are generally expensive.

(41) When it is desired to use a push-in type commercially available nipple valve 30 that typically has a gasket 46 to obtain a watertight seal, the inner diameter of the heat pipe may be selected and enlarged or reduced at the lower end of the heat pipe to accommodate gasket 46. When it is desired to use a threaded type commercially available nipple valve 30 the inner diameter of the heat pipe may be selected and enlarged or reduced at the lower end of the heat pipe to accommodate threads for a sealed threaded joint. In one preferred embodiment, the inner diameter of the heat pipe is in the range of about to about inches, and the length L is in the range of 0.5 to about 5 inches. In one more-preferred embodiment, the inner diameter is in the range of 5/16 to about 7/16 inches, and the length is in the range of about 1 to about 4 inches. The annular thickness of the heat pipe is selected so that the thermal resistance .sub.p as given by Eqn. (1) is sufficiently small that T.sub.rp is a small fraction of the temperature differential between the reservoir and the exposed surface 32 of the nipple. The length may be selected so that the top of the heat pipe protrudes sufficiently into the reservoir above surface 100 so that a heater, e.g., an electric heater, an example of which is an electric aquarium heater, can be placed between the lower surface of the reservoir and the top of the heat pipe. Such placement may ensure that the heat pipe inlet will be proximate to the warmest water in the reservoir. Similarly, when the present invention is mounted in a supply pipe, the length of the heat pipe may be selected so that the inlet of the heat pipe is proximate to the warmest water in the pipe, and further, the length may be selected to not unacceptably impede the flow of water in the pipe.

(42) The sleeve 20 is made of good conducting metal such as the examples given for the heat pipe 10. In one preferred embodiment, the sleeve is made of aluminum, brass, copper, or alloys thereof. In one more-preferred embodiment, it is made of copper or alloys thereof. The sleeve must make sufficiently close contact with the body of the nipple valve 36, and/or with a good conducting metal ring 130 (shown in FIGS. 4-11) that makes sufficiently close contact with the metal annular cylinder comprising the lower member 32 of the nipple valve seat where the actuator pin 34 makes contact.

(43) In one preferred embodiment, the sleeve 20 is a clamped sleeve comprising an annular cylinder with an axial slot 22 so that it can be more easily compressed radially when clamped to obtain a sufficient contact pressure. With sufficient clamping pressure P.sub.c, it is found that the thermal contact resistance .sub.c can be made sufficiently small, so that an acceptable temperature difference results .sub.c. The clamped sleeve 20 should be sufficiently malleable so that it can conform to the body of the nipple valve 36 with minimal clamping force. Such malleability can be obtained by selection of material and/or alloy and by softening the material, e.g., by heat treatment. In one more-preferred embodiment, the clamped sleeve 20 is of copper and has an annular thickness of about 1 to 3 mm (0.04 to 0.12 inches) and a length L.sub.sleeve that is comparable to the length of the principal body of the nipple valve 36 plus an additional length so that the upper portion can be clamped onto the lower portion of the heat pipe 10. For example, when the nipple valve 20 is an Impex 420011 nipple valve, for which the lower principal portion of the nipple valve is about inch, in one preferred embodiment, the length of the clamped sleeve L.sub.sleeve is about 2.5 to 3.5 cm, i.e., about 1.0 to 1.4 inches inche, so that the clamped sleeve overlaps the heat pipe by about 5-10 mm or about 0.2 to about 0.4 inch

(44) There are a variety of elastic/plastic models of thermal contact between a plastic and a metal; examples are Greenwood and Williamson (1966), Cooper, Mikic, and Yovanovich (CMY model, 1969), Persson (2006), Jackson and Streator (2006), Bahrami, Yovanovich, and Marotta (2006), Carbone (2009), Jackson and Green (201), and Tian, Zhao, Zhu, and Qin (2012). These models predict a thermal conductance at the plastic-metal joint that depends on the joint contact surface area and the distribution of size, geometry, and density of asperities and features (collectively, the surface parameters) that behave elastically and/or plastically under clamping load pressure between the plastic and metal. At low loading pressure, the joint is in the microscopic resistance regime, and the low conductance of the joint in comparison with the bulk conductance of the plastic material results in the joint contact resistance .sub.c being much larger than the bulk polymer layer resistance .sub.bulk. However, at high loading pressure, the joint is in the bulk polymer resistance regime, and .sub.c becomes comparable to or smaller than .sub.bulk.

(45) Use of the cited models to predict .sub.c is difficult without knowledge of the actual apparent contact area, the surface roughness and surface finish, and the surface parameters. Many of the models are based on highly polished surfaces or on optically flat mating surfaces. While the computational simulation models can account in principle for imprecise shapes and deformation of the mating objects that comprise the joint, in practice, such knowledge is not readily available. Some models allow a corrective factor that is the ratio of actual to apparent geometrical surface area, however, even knowledge of this factor may be difficult to ascertain. Further, measurement or detailed knowledge of the surface parameters that may vary from piece to piece in a production of inexpensive parts is impractical. Thus, it was not a priori obvious that .sub.c can be made small enough at practical clamping force for the purposes of the instant invention.

(46) The pressure exerted by the clamped sleeve 20 on the heat pipe, the body of the nipple valve, or the optional conducting metal ring 130 is approximately given by

(47) $\begin{array}{cc}{P}_c=\frac{2F}{D_{\mathrm{sl}}{L}_{\mathrm{sleeve}}},& \left(14\right)\end{array}$
where D.sub.sl is the inner diameter of the clamped sleeve 20, and F is the tensile force exerted by the clamping means. This is a macroscopic average pressure.

(48) As reported by Fuller and Marotta, in the microscopic resistance regime,

(49) $\begin{array}{cc}\log \left(\frac{h_c}{k_s{m}_{\mathrm{ab}}}\right)\log \left(\frac{2.3P_c}{E_p{m}_{\mathrm{ab}}}\right),& \left(15\right)\end{array}$
where h.sub.c is the contact heat transfer coefficient, is the mean surface roughness, k.sub.s is the mean bulk conductivity of the metal and plastic, m.sub.ab is the mean surface slope of asperities, and E.sub.p is the elastic modulus of the plastic. Implicit in this model is the assumption that the pressure is applied over the mating pieces and that the surfaces are in proximate or sufficiently close contact. Generally, this assumption is only approximate for a metal clamped sleeve on a plastic nipple body unless fabrication processes are used to obtain good macroscopic feature and part conformance, relatively smooth surface finish and surface roughness. Nonetheless, an illustrative estimate of combined joint contact conductance and bulk conductance can be obtained with the parameter values of k.sub.s2k.sub.p, i.e., twice the conductivity of the plastic, m.sub.ab0.21, typical surface roughness 5 m, and E.sub.p3.610.sup.9 Pa. The data of Marotta and Fletcher and Fuller and Marotta show that when and for

(50) $\frac{2.3P_c}{E_p{m}_{\mathrm{ab}}}0.001,\mathrm{then},\frac{h_c}{k_s{m}_{\mathrm{ab}}}2{10}^2,$
greater values of P.sub.c, the joint conductance increases relatively slowly as a function of P.sub.c, and the joint conductance is in the bulk polymer resistance region and .sub.c.sub.bulk. For the parameter values given above, this critical value P.sub.crit occurs at about P.sub.crit50-100 psi applied pressure.

(51) Comparison with the data of Fuller and Marotta can be made although the actual surface conditions and actual values or , m.sub.ab, P.sub.c, and joint surface area are not readily determined or known for the components of the freeze-resistant nipple valve device. For an applied P.sub.c150 psi on acetal homopolymer (e.g., Delrin by DuPont) plastic, with the parameter values of k.sub.s2k.sub.p0.76 W/m-K, i.e., twice the conductivity of the plastic, m.sub.ab0.57, typical surface roughness 2.2 m, and E.sub.p3.610.sup.9 Pa. their results correspond to

(52) $\frac{1}{h_c}0.0056m^2\text{-}K\text{/}W.$
The contact conductance h.sub. and h.sub.bulk are related to h.sub.c by the following relation,

(53) $\begin{array}{cc}\frac{1}{h_c}=\frac{1}{h_{}}+\frac{1}{h_{\mathrm{bulk}}}=\frac{1}{h_{}}+\frac{}{k_p\left(1-\frac{P_c}{E_p}\right)},& \left(16\right)\end{array}$
where is the thickness of the plastic. From the experimental parameters and data of Fuller and Marotta, 1/h.sub.bulk0.0035, and 1/h.sub.0.0021, i.e., h.sub.bulk287 W/m.sup.2-K and h.sub.482 W/m.sup.2-K, so, the interface contact resistance is about 1.7 times the bulk polymer resistance.

(54) In an experimental test, a one gallon reservoir container was filled with warm water, T.sub.init112 F. (44 C.), and the temperature of the reservoir T.sub.r and the temperature T.sub.n at the exposed surface at the end of the nipple 32 were measured as a function of time. Temperatures were measured with type K thermocouples comprising welded 0.25 mm diameter wire chromel-alumel junctions and where the measuring thermocouple was in series with a reference junction thermocouple that was immersed in a glass container of ice water at T.sub.ref40 F. The thermocouple junction that measured T.sub.n was spot welded onto the exposed surface of the nipple 32. Because of the small distance between the exposed face 32 and the nipple valve seat, it is assumed that T.sub.nT.sub.ns within about a degree C. With an ambient temperature T.sub.a21 C., the initial temperature differential between the reservoir and the ambient air was 23 C., which is comparable to the difference between a reservoir temperature just above the freezing point of water and an ambient temperature of approximately 0 F.

(55) For a nipple mounted by a rubber bushing 46 on a heat pipe held in a feed-through comprising a rubber grommet 83, but with no outer shield or clamped sleeve, the temperature T.sub.nT.sub.a+TT.sub.r23( C.)+T with T5 C. after about 6 minutes. When the unshielded nipple is exposed to an approximately 9 mph wind, T.sub.nT.sub.a+T, and T is 2.5 C. at quasi-equilibrium within less than 6 minutes. In a controlled experimental comparison, a freeze-resistant nipple valve device 5 with a clamped-sleeve, outer shield, and reflective heat shield is found to have a quasi-equilibrium T.sub.nT.sub.rT, where T7.5 C. after about 10 minutes with a wind of approximately 9 mph. In another controlled experimental comparison, a freeze-resistant nipple valve device 5 with a clamped-sleeve, a conducting metal ring 130, outer shield, and reflective heat shield is found to have a quasi-equilibrium T.sub.nT.sub.rT, where T5 C. after about 10-15 minutes.

(56) For the insulated, shielded, nipple valve device 5 used in the above experimental example, when T.sub.ns53 C., and Q.sub.n0.1 W (laminar flow case), then .sub.In50 K/W. As the overlap area is A.sub.c4 cm.sup.2 for the overlap of the clamped sleeve 20 in the vicinity of the metal annulus comprising the lower portion of the nipple valve seat and the exposed lower surface 32 of the nipple valve, the corresponding value based on the Fuller and Marotta results is .sub.EN14 K/W. By comparison, the bulk thermal resistance of a Delrin plastic body of a nipple valve at the overlap area is .sub.bulk9.9 K/W. Thus, the combination of effective contact area and surface parameters appears to result in our experimentally realized .sub.c1.sub.c240 K/W, which is about a factor of 3 greater than would be predicted from the data of Fuller and Marotta. Nonetheless, .sub.sn is sufficiently small for the objective of the present invention.

(57) It is found that any of several conventional means for clamping cylindrical objects can be used to apply adequate force F. Such means include plastic cable ties, metal wire wrapped circumferentially around the clamped sleeve with the ends of the wire twisted to generate the clamping force, and common hose clamps, either of plastic or metal. In one preferred embodiment, the clamping means should be small in size and of small mass, and it should provide stable applied force in spite of temperature changes that cause expansion and contraction; and further, it should be stable for long time duration such as a year or more. In one more-preferred embodiment, the clamping means comprises one or more metal wires 90 wrapped around the clamped sleeve 20 and with the wire ends twisted. In one still more-preferred embodiment, at least two wires are used, one of which provides clamping force in the vicinity of the overlap of the clamped sleeve 20 and the heat pipe 10, and the wire is of stainless steel or other corrosion resistant metal. In such an embodiment, it is found that a 1 mm diameter stainless steel wire of 300 series (Ausinitic) alloy with ends twisted can apply about 12 pounds of tensile force or more. Thus, for a clamped sleeve inner diameter of D.sub.sl=0.25 inches and L.sub.sleeve=1.0 inches, and an applied force of 12 pounds with a single clamp wire 90, a clamping pressure of P.sub.c=48 psi (3.310.sup.5 Pa) is generated. With three clamp wires, the clamping pressure is about 150 psi. In a preferred embodiment, the clamp wire has diameter in the range of 0.5 mm to about 2 mm.

(58) The mounting and feed-through connection to a reservoir container 50 may comprise a tubulation with a flange that is attached to the wall of the reservoir container 50 by any of several means known in the art and sealed by a gasket, grommet, bushing, o-ring, waterproof sealant, room-temperature-vulcanizing rubber (RTV) such as a silicone glue, or other means known in the art. In one preferred embodiment, the mounting and feed-through connection comprises a male part 75 and a female part 76, either of which may have a flange so that when the parts are assembled, the wall of the reservoir container is held between the parts 75 and 76, and a gasket, waterproof sealant, or silicone glue seals the joint between the reservoir container and the feed-through. In one preferred embodiment, the male part 75 is a Schedule 40 PVC pipe plug that is drilled with a through hole to accept the heat pipe and sealing means, and example of which is a tubular gasket comprising a short length of polymer tubing 70 such as vinyl tubing, and the female part 76 is one-half of a Schedule 40 PVC pipe coupling, said pipe coupling and pipe plug being either of the slip fit type or threaded type. In one more-preferred embodiment, the said pipe coupling and pipe plug are of the slip fit type. In another preferred embodiment, the male part 75 of the feed-through may comprise a threaded tubulation that is screwed into the wall of the reservoir container 50 and sealed by any of several methods known in the art. Such a feed-through connection is one preferred embodiment for mounting the nipple valve assembly 5 into a supply pipe. In a preferred embodiment, the heat pipe 10 protrudes through the feed-through and may be sealed by compression of a gasket, or a cylinder of polymer tubing, for example 70 (as shown in the figures), or sealant, or an o-ring. In one more-preferred embodiment, the feed-through is a rubber or elastomer grommet 83 made of 50-60 Durometer FDA listed material for food or potable water contact such as silicone, Buna-N nitrile, EPDM, or neoprene. To increase the compression of the grommet, one or more potable water compatible plastic or rubber sleeves 87 may be situated on the heat pipe 10 within the inner diameter hole in the grommet 83. Examples of such a sleeve 87 is a length of cylindrical PVC or Teflon heat-shrinkable tubing that is heat treated to tightly shrink fit onto the heat pipe 10 to form a watertight seal.

(59) The reflective heat shield 110 surrounding the nipple valve 30 and sleeve 20, and forming one surface of the air gap 8 may comprise any of several low emissivity materials such as a foil or metalized film. In one preferred embodiment, the foil or film is aluminum with an emissivity less than 0.10, i.e, 0.10. In one preferred embodiment, the aluminum foil has a thickness in the range of 0.0005 to 0.003 inches (about 12 to 75 micrometers). In one more-preferred embodiment, the reflective heat shield 110 comprises aluminized polyester, such as aluminized Mylar, in which the plastic film has a thickness in the range of 0.001 to 0.010 inches (about 25 to 250 micrometers), and the metallization on the plastic film has a thickness in the range of about 0.3 to 25 micrometers. In one preferred embodiment, the reflective heat shield 110 is attached to a plastic material neighboring the air gap 8 such as the interior wall of the outer bucket, or the insulation 140, or the outer shield mounting sleeve 80, or it is attached to the outer surface of the sleeve 20. The means of attachment may be any of several known in the art. In one preferred embodiment, the attachment is by adhesive, an example of which is a spray applied adhesive such as 3M's 777 spray adhesive. In another preferred embodiment wherein the air gap 8 surrounds the thermal insulation 140, the reflective heat shield 110, and the sleeve 20, the insulation 140 and reflective heat shield 110 are held against the sleeve 20 by one or more of the following, a plastic cable tie, a tie wire, adhesive, adhesive tape, heat shrinkable tubing, an elastic band, or any commonly used means of fastening.

(60) The outer shield 84 that provides protection from exterior ambient cold or hot air also provides protection from pecking by birds and from damage to the nipple valve device 5 in case the assembly comes in contact with the ground or is bumped into another object. Accordingly, the outer shield 84 and its mounting that may be via a sleeve 80 attached to part 75 must be sturdy and easily cleaned. In one preferred embodiment, it is also made of thermal insulating material such as plastic, an example of which is PVC. In one more-preferred embodiment, the outer shield 84 comprises a Schedule 40 PVC pipe cap in which an orifice is made so that the nipple valve 30 can protrude. In one still more-preferred embodiment, the Schedule 40 PVC pipe cap is mounted on a PVC pipe adapter that comprises an outer shield mounting sleeve 80 that is mounted onto the feed-through part 75 and may be optionally attached by one or more screws. In one preferred embodiment, the exposed lower surface 32 of the nipple valve is approximately flush with the outer surface of the outer shield 84 at the orifice in the outer shield. In an alternate embodiment, the outer shield includes an air gap, air spaces within its construction, a low thermally conductive material, and the like.

(61) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through connection (75-76) to a reservoir container 50 or supply pipe is shown in FIG. 2. A heat conductive clamped sleeve 20 surrounds the body of the nipple valve 30. An air-gap 8 and reflective heat shield 110 surround the nipple valve 30 and clamped sleeve 20. An outer shield 84 provides protection from exterior ambient cold or hot air. Insulating material 140 such as polyethylene foam insulation within the outer shield surrounds the air-gap.

(62) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through (75-76) connection to a container 50 or supply pipe is shown in FIG. 3. A heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30. An air-gap 8 and reflective heat shield 110 surround the nipple valve 30 and clamped sleeve 20. An outer shield 84 provides protection from exterior ambient cold or hot air. An annular insulating washer 128 made of cork or other insulating material with good durability in a moist environment centers the clamped sleeve 20 and nipple valve 30 in the opening, i.e., orifice, of the outer shield 84; it also reduces infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. In one preferred embodiment, the said orifice has a diameter that is at least one-half millimeter larger than the outer diameter of the clamped sleeve 20 so that the clamped sleeve and nipple valve are not in good thermal contact with the outer shield 84.

(63) One preferred embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 20, mounting and feed-through connection (75-76) to a reservoir container 50 or supply pipe is shown in FIG. 4. A heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30 and also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. In one preferred embodiment, the heat conductive ring is an annulus with an axial slit and outer and inner diameters selected so that when the said ring is held by the clamped sleeve, the applied pressure is transmitted from clamped sleeve 20 to conductive ring 130 to the metal annulus with exposed surface 32. In one preferred embodiment, the heat conductive ring 130 is made of any or a combination of the following or their alloys, or other heat conductive materials known in the art, good conducting metal, aluminum, copper, brass, bronze, silver, stainless steel, a platinum group metal, combinations thereof, or alloys thereof. In one more-preferred embodiment, the material of the heat conductive ring 130 is selected for low susceptibility to corrosion in a wet or weather-exposed environment or for low toxicity. An air-gap 8 and reflective heat shield 110 surround the nipple valve 30 and clamped sleeve 20. The clamped sleeve is clamped by three wire rings 90, each with ends twisted to apply a force of approximately 10 pounds or more. An outer shield 84 provides protection from exterior ambient cold or hot air.

(64) As the heat conducting ring 130 described above may contact only an axial portion of the metal annulus with exposed surface 32, it is necessary that the applied clamping pressure in the vicinity of the said heat conducting ring 130 be sufficient so that the heat resistance that is the sum of the heat resistance of the contact interface between the clamped sleeve 20 and the heat conducting ring 130, the heat resistance of the conducting ring, and the heat resistance of the contact interface between the conducting ring 130 and the metal annulus with exposed surface 32 is sufficiently small so that the temperature difference between the metal annulus and the clamped sleeve is acceptably small. As with the plastic-metal thermal contact conductance phenomenology described above, the metal-metal thermal contact conductance depends on the surface parameters and surface finish, as well as the effective contact area and elastoplastic properties of the materials. Generally, it is known in the art (see, for example, Yovanovich 2005) that in metal-metal joints with surface finishes obtained by common machining and common fabrication methods, and with applied pressure greater than about MPa (i.e., about 50 psi), that joint thermal resistance of the order of 10.sup.4 K-m.sup.2/W or less can be obtained. As the apparent contact surface area for conducting ring 130 may be about 0.1 cm.sup.2 or greater, then, the bulk resistance of the conducting ring 130 is about 10 K/W when the annular thickness of the conducting ring is about 1.5 mm, and, then, the joint contact resistances are comparable to the bulk resistance of the conducting ring. With greater clamping pressure, the contact resistance will be less. Thus, when the heat loss at the metal annulus exposed surface 32 is about 0.1 W and the clamping pressure is P.sub.crit, a temperature difference of about one degree or less may be expected, and the heat conducting ring 130 may significantly aid the heat transfer between the clamped sleeve and the nipple valve metal annulus with exposed surface 32.

(65) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through connection (parts 75 and 76) to a reservoir container 50 or supply pipe is shown in FIG. 5. A heat conductive clamped sleeve 20 clamped by wire rings with twisted ends 90 surrounds the body 36 of the nipple valve 30. In one more-preferred embodiment, the clamped sleeve 20 also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. In one preferred embodiment, an insulation filled space 140 surrounds the nipple valve 30 and clamped sleeve 20. An outer shield 84 attached to mounting sleeve 80 provides protection from exterior ambient cold or hot air. In one preferred embodiment, the insulation has thermal conductivity less than 0.07 W/m-K, examples of such are polyethylene foam sheet, cork, other foamed plastics, aerogel, Perlite (expanded volcanic glass), and fiber insulation materials.

(66) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through connection (75-76) to a reservoir container 50 or supply pipe is shown in FIG. 6. A heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30. In one more-preferred embodiment, the clamped sleeve 20 also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. An air-gap 8 and reflective heat shield 110 surround the nipple valve 30 and clamped sleeve 20. An outer shield 84 attached to mounting sleeve 80 provides protection from exterior ambient cold or hot air. An annular insulating washer 128 made of cork or other insulating material with good durability in a moist environment centers the clamped sleeve 20 and nipple valve 30 in the opening, i.e., orifice, of the outer shield 84; it also reduces infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. In one preferred embodiment, the said orifice has a diameter that is at least one-half millimeter larger than the outer diameter of the clamped sleeve 20 so that the clamped sleeve and nipple valve are not in good thermal contact with the outer shield 84.

(67) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 10, mounting and feed-through connection (75-76) to a reservoir container 50 or supply pipe is shown in FIG. 7. A heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30. In one more-preferred embodiment, the clamped sleeve 20 also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. An air-gap 8 and reflective heat shield 110 surround the nipple valve 30 and clamped sleeve 20. An outer shield 84, attached to mounting sleeve 80, provides protection from exterior ambient cold or hot air. An annular insulating washer 128 made of cork or other insulating material with good durability in a moist environment centers the clamped sleeve 20 and nipple valve 30 in the opening, i.e., orifice, of the outer shield 84; it also reduces infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. In one preferred embodiment, the insulation has thermal conductivity less than 0.07 W/m-K, examples of such are polyethylene foam sheet, cork, other foamed plastics, aerogel, Perlite (expanded volcanic glass), and fiber insulation materials. In one preferred embodiment, the said orifice has a diameter that is at least one-half millimeter larger than the outer diameter of the clamped sleeve 20 so that the clamped sleeve and nipple valve are not in good thermal contact with the outer shield 84. Additionally, insulating material 140 such as polyethylene foam or the examples of such insulation listed above surrounds the reflective heat shield 110 and air-gap 8 within the outer shield 84.

(68) An embodiment of an insulated, shielded, nipple valve device 5 with a heat pipe 20, mounting and feed-through connection (75-76) to a reservoir container 50 or supply pipe is shown in FIG. 8. A heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30. In one more-preferred embodiment, the clamped sleeve 20 also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. Insulating material such as polyethylene foam surrounds the clamped-sleeve and nipple valve. A reflective heat shield 110 surrounds the insulating material 140 or is incorporated into the insulating material and the heat shield or insulating material with incorporated heat shield defines the inner surface of an air-gap 8 within an outer shield 84, attached to mounting sleeve 80, which provides protection from exterior ambient cold or hot air. In one preferred embodiment, the insulation has thermal conductivity less than 0.07 W/m-K, examples of such are polyethylene foam sheet, cork, other foamed plastics, aerogel, Perlite (expanded volcanic glass), and fiber insulation materials. Optionally, the insulating material 140 extends downward to the inner surface of the outer shield 84 to center the clamped sleeve 20 and nipple valve 30 in the opening of the outer shield, and to reduce infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. In one preferred embodiment, the said orifice has a diameter that is at least one-half millimeter larger than the outer diameter of the clamped sleeve 20 so that the clamped sleeve and nipple valve are not in good thermal contact with the outer shield 84.

(69) An embodiment of a freeze-resistant nipple valve device 5 with a heat pipe 10, clamped sleeve 20, mounting and feed-through connection to a container or supply pipe wherein the feed-through comprises a rubber or elastomer grommet 83 is shown in FIG. 9. The heat conductive clamped sleeve surrounds the body of the nipple valve 36 and also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. Insulating material 140 such as polyethylene foam surrounds the clamped-sleeve and nipple valve. A reflective heat shield 110 surrounds the insulating material or is incorporated into the insulating material and the heat shield or insulating material with incorporated heat shield defines the inner surface of an air-gap 8 within an outer shield 84 that provides protection from exterior ambient cold or hot air. The outer shield is slipped onto a mounting sleeve 80 that surrounds the heat pipe 10. In the embodiment shown in the figure, the mounting sleeve 80 surrounds a portion of the insulating material 140. In one preferred embodiment, the outer shield 84 is made from a PVC pipe cap, and the mounting sleeve 81 is made from a PVC pipe plug. The mounting sleeve may be held onto the heat pipe 10 or insulating material 140 by adhesive or glue or one or more fastening devices, e.g., a screw, a spring, a clip, threads, etc. The outer shield may be fixed onto the mounting sleeve by a screw or set screw, which may be made of plastic or metal. Optionally, the insulating material extends downward to the inner surface of the outer shield to center the clamped sleeve and nipple valve in the opening of the outer shield, and to reduce infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. In the embodiment shown, the outer shield and/or mounting sleeve are in contact with the outer surface 200 of the reservoir container 50. Optionally, the spacing between the grommet 83 and the mounting sleeve 81 may be minimized or filled with insulation material to reduce heat loss from the heat pipe 10.

(70) An embodiment of a freeze-resistant nipple valve device 5 with a heat pipe 10, clamped sleeve 20, mounting and feed-through connection to a container or supply pipe wherein the feed-through comprises a rubber or elastomer grommet 83 is shown in FIG. 10 as a vertical plane cross-section view. The heat conductive clamped sleeve 20 surrounds the body 36 of the nipple valve 30 and also clamps a heat conductive ring 130 that makes good thermal contact with the metal annulus with exposed surface 32 at the lower end of the nipple valve seat. Insulating material 140 such as polyethylene foam surrounds the clamped-sleeve and nipple valve. A reflective heat shield 110 surrounds the insulating material or is incorporated into the insulating material and the heat shield or insulating material with incorporated heat shield defines the inner surface of an air-gap 8 within an outer shield 84 that provides protection from exterior ambient cold or hot air. The outer shield is mounted on an annular part 81 that is affixed to the heat pipe. Optionally, the insulating material extends downward to the inner surface of the outer shield to center the clamped sleeve and nipple valve in the opening of the outer shield, and to reduce infiltration of ambient exterior air into the space between the clamped sleeve and the outer shield. Also optionally, a thin-walled tubular sleeve 87 surrounds the heat pipe 10 in the vicinity of the grommet so that additional radial compression of the grommet 83 results to improve the sealing of the grommet. In one preferred embodiment, the tubular sleeve comprises heat shrinkable tubing made of potable water compatible material, examples of which are PVC and Teflon, and wherein the tubing is heat shrink fitted onto the heat pipe 10 for a water tight seal.

(71) Also shown in FIG. 10 is an end view of the bottom of the freeze-resistance nipple device 5 to reveal the relation between the clamped sleeve 20, the conductive metal annulus 130, and the body of the nipple valve 36. In one preferred embodiment, the clamped sleeve has an axial 22 slot so that the clamping means 90 can compress the sleeve, and the conductive metal annulus 130 has an axial slot 132 so that it can be compressed by the clamped sleeve 20 onto the annular metal part at the end of the nipple valve 30. In one preferred embodiment, the two slots 22 and 132 are oriented so that they are not at the same azimuthal position relative to the axis of the nipple valve 30.

(72) The embodiment shown in FIG. 10 as a vertical plane cross-section view is also shown in FIG. 11 with two views of a horizontal cross-section. The cross-section view on the lower left is shown in the same scale as the vertical plane cross-section view in the upper left. The view to the right is the horizontal plane cross-section view magnified 2. In this view, the internal weight, e.g., a stainless steel sphere, which is found in some nipple valves is seen. Surrounding this is an annular space within the stainless steel wall 33 of annular part with exposed face 32 that is within the nipple valve body 36. The clamped sleeve 20 surrounds the nipple valve body. A vertical slot 22 in the clamped sleeve 20 is seen. In one preferred embodiment, the width of this slot after compression of the clamped sleeve 20 by the clamping means, e.g., one or more wire loops with twisted ends 90 (shown as a dashed hidden line in the horizontal plane cross-section views), is between 0.005 inches and about 0.1 inches. In another preferred embodiment, the clamped sleeve is a continuous thin-walled cylinder with an axially oriented boss or folds that allow the clamped sleeve to be compressed to make a good thermal conductance contact with the nipple valve body.

(73) It is to be understood, that the configuration of the thermal insulation and reflective heat shield(s) in the freeze-resistance nipple device 5 may be any of those shown in FIGS. 1-11 or such as may be derivative to the teachings herein where the feed-through comprises two parts, a grommet, a half-grommet, a compression sleeve, a threaded-joint seal, or other means known in the art. Further, the thermal insulation may comprise plastic foam, bubble wrap, cork, aerogel, composite containing aerogel, expanded volcanic rock, e.g., the commercial product known as, Perlite, glass or plastic thin-walled micro-spheres, a vacuum insulation sleeve comprising one or more reflective heat shields and an annular vacuum space, or other high performance, low thermal conductance materials. The outer shield 84 may be made of insulating material so that the insulation 140 and outer shield are the same component. The outer shield 84 and thermal insulation 140 may be individually or together molded onto the sleeve 20. The reflective shield 110 may be a separate component, or it may be incorporated into the thermal insulation material, and example of such being a commercial product known as Reflectix.

(74) Shown in FIG. 12 is an elevation view of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device 5 with a heat pipe, clamped sleeve, mounting and feed-through connection, and outer shield. In this embodiment, the outer enclosure is a plastic bucket 300 with a wire bail handle comprising parts 302 and 304 and a length of chain 306 that provide a means of mounting the waterer by hanging. The reservoir container 50 is a plastic bucket that is removable and set inside the outer enclosure. Both the outer enclosure and the reservoir container have removable lids 310 and 360. Thermal insulation comprising one or more annular layers, e.g., 405 and 410 line the interior surface of the outer enclosure 300 and one or more reflective heat shields, e.g., 415, 432, and 448 line most of the surfaces of the thermal insulation, e.g., 410, 430, and 444, which are adjacent to spaces between the outer enclosure and the reservoir container. One or more layers of thermal insulation 430 cover the bottom interior of the outer enclosure 300. One or more layers of thermal insulation, e.g., 440, 442, and 440 cover the lid of the reservoir container. In one preferred embodiment, at least one layer extends to cover the annular space 216 between the thermal insulation 410 and the wall of the reservoir container 350. Insulating spacers 433 may provide support between thermal insulation 430 and reservoir container 50 to provide for a greater vertical thickness of air gap 214. The outer enclosure and reservoir container have orifices so that an electrical immersion heater, an example of which is an immersible aquarium heater, can be placed inside the reservoir container and its power cord passed through orifices, for example but not as a limitation, a notch 472 in lid 310 that may align with a notch in outer enclosure 300 and an orifice with a cap 470, so that connection to an electrical power source that is external to the waterer can be made. Optionally, the lid of the reservoir container 360 may have an orifice with a removable plug 468 so that the reservoir container may be filled, or the water level or temperature can be checked without removing the reservoir container from the outer enclosure.

(75) Shown in FIG. 13 is a cross-section view of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device with a heat pipe, clamped sleeve, mounting and feed-through connection, and outer shield. In this embodiment, the outer enclosure is a plastic bucket with a wire bail handle and a length of chain that provide a means of mounting the waterer by hanging. The reservoir container is a plastic bucket that is removable and set inside the outer enclosure. Both the outer enclosure and the reservoir container have removable lids. Insulation and one or more reflective heat shields line most of the inner surface of the outer enclosure. One or more layers of insulation cover the reservoir container. The outer enclosure and reservoir container have orifices so that an electrical immersion heater, an example of which is an immersible aquarium heater, can be placed inside the reservoir container and its power cord passed through orifices so that connection to an electrical power source that is external to the waterer can be made. Optionally, the lid of the reservoir container may have an orifice with a removable plug so that the reservoir container may be filled, or the water level or temperature can be checked without removing the reservoir container from the outer enclosure.

(76) Shown in FIG. 14 is a top plan view of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device with a heat pipe, clamped sleeve, mounting and feed-through connection, and outer shield. In this view, the wire bail handle comprising parts 302 and 304 and mounting chain 306 are shown rotated 90 degrees from the vertical. The wire bail is attached to protrusions 301 on the wall of the outer enclosure 300. Also shown are the heater power cord orifice 364 that has a notch and a cap 470 and the removable plug 468 and its respective orifice in the lid of the reservoir container; these orifices being shown as hidden features denoted by dashed lines.

(77) Shown in FIG. 15 is a bottom plan view of a low heat-loss rate waterer with an integrated, shielded, freeze-resistant nipple valve device 5 with a heat pipe, clamped sleeve, mounting and feed-through connection, and outer shield 84. Also shown is a raised annulus 202 that is a common feature of commercially available plastic buckets that may serve as the outer enclosure 300. Not shown is the wire bail handle that is also a common feature of such buckets.

(78) A low heat-loss rate waterer with an integrated insulated, shielded, nipple valve device 5 with a heat pipe, mounting and feed-through connection to a reservoir container 50 is shown in FIG. 16. In the embodiment shown, an optional feed-through is provided that is mounted on the lid of the reservoir container and a plugged or capped tubulation that penetrates an orifice in the lid of the outer enclosure so that the reservoir container may be filled, or the water level or temperature checked without removing the lids of the outer enclosure or the reservoir container.

(79) In one preferred embodiment, container 50 is a food-grade plastic bucket with thin wall 350 and a removable lid 360. The plastic bucket may optionally have reinforcements 358 for the attachment of a bail handle. The reservoir container 50 is removable and mounted inside an outer bucket 300 so that air spaces 214, 216, and 218 are defined below, on the side, and above container 50. In one preferred embodiment, outer bucket 300 is a food-grade plastic bucket with a removable lid 310. In one more-preferred embodiment, the container 50, outer bucket 300, and lids 360 and 310 are made of high density polyethylene (HDPE) and are food-grade

(80) The reservoir container 50 is mounted on low thermal conductance supports 433. In one preferred embodiment, these supports may comprise an annular ring or pieces thereof or conveniently shaped slabs of insulation with thermal conductivity less than about 0.2 W/m-K, examples of which are plastic foam insulation such as Styrofoam sheet, cork, or fiber materials. In another preferred embodiment, the supports 433 are two or more thin walled rigid plastic shapes, an example of which is a cylinder of PVC pipe that is attached, for example by a screw, to the bottom wall of outer bucket 300 and may be optionally covered in reflective heat shield film or foil that is attached by adhesive. In one preferred embodiment, the container 50 rests on the supports 433. Optional low thermal conductance spacers may be situated in the air gap space 216 to locate reservoir container 50 at a desired radial position within the outer bucket 300 may be attached to either the reservoir container or the outer bucket.

(81) The use of insulation material to partially fill the spaces between the reservoir container 50 and the outer bucket 300 in addition to the air gaps 214, 216, and 218 results in smaller heat flux from the reservoir container to the exterior of the outer bucket. In one preferred embodiment, one or more layers of insulation material 405, 410 with thermal conductivity less than about 0.07 W/m-K covers most of the interior side wall of the outer bucket 300. In one more-preferred embodiment, one or more layers of insulation material 440, 442, 444 cover the top lid 360 of the reservoir container 50. In one still more preferred embodiment, a layer of insulation material 430 covers the bottom of the interior of outer bucket 300.

(82) The thicknesses of the insulation layers and the air gap spaces are selected to obtain a sufficiently small heat flux loss from the reservoir container. In one preferred embodiment, the reservoir container 50 is a 2 gallon bucket and the outer bucket 300 is a 5 gallon bucket. In another preferred embodiment, the reservoir container 50 is a one gallon bucket and the outer bucket 300 is a 2 gallon bucket. Such buckets are available as food grade HDPE buckets. In one preferred embodiment, the layers of insulation material inside the side wall of the outer bucket comprise a thickness in the range of about 0.75 to about 1.5 cm. This insulation may comprise one or more layers. In FIG. 12, as one preferred embodiment, two layers, each of about 0.5 cm thickness are shown. Suitable insulation materials have been described above. In one more-preferred embodiment, the insulation material comprises polyethylene foam sheets, each of thickness about 0.5 cm per layer. In one preferred embodiment, the insulation above the lid 360 of the reservoir container comprises a thickness in the range of about 1.0 cm to about 2 cm and may comprise one or more layers of insulation material. In one more-preferred embodiment, the insulation material comprises polyethylene foam sheets, each of thickness about 0.5 cm per layer. In one preferred embodiment, at least one layer of insulation material is below the reservoir container 50 within the outer bucket 300 and comprises a thickness in the range of about 0.5 cm to about 1.0 cm. The insulation material may be inserted into the outer bucket and not fixed to the outer bucket, or it may be attached by fasteners or low conductivity material, an example of such being plastic screws, for example nylon screws, or it may be attached by adhesive. In one preferred embodiment, the adhesive is a spray adhesive.

(83) In one preferred embodiment, a heat reflective shield is located on one of the surfaces defining each of the air gap spaces 214, 216, and 218. The reflective heat shield may be located on the surfaces of the air gap spaces that are closest to the reservoir bucket 50 or to the outer bucket 300. In one preferred embodiment, a reflective heat shield 415 is attached to the inner surface of the side wall insulation 410, a reflective heat shield 432 is attached to the inner surface of the bottom insulation layer 430, and a reflective heat shield 448 is attached to the outer surface of the top insulation layer 448. In one preferred embodiment, the foil or film is aluminum with an emissivity less than 0.10, i.e, 0.10. In one preferred embodiment, the aluminum foil has a thickness in the range of 0.0005 to 0.003 inches (about 12 to 75 micrometers). In one more-preferred embodiment, the reflective heat shields 415, 432, and 448 comprise aluminized polyester, such as aluminized Mylar, in which the plastic film thickness is in the range of 0.001 to 0.010 inches (about 25 to 250 micrometers), and the metallization film has a thickness in the range of about 0.3 to 25 micrometers.

(84) In another more preferred embodiment, one or more reflective heat shields are incorporated into the thermal insulation. A commercial product comprising such is known as Reflectix. One or more layers of such insulation having incorporated heat shield(s) may comprise the thermal insulation elements 430, 405, 410, 440, 442, 444, and 433 and reflective heat shield elements 432, 415, and 448 within the outer enclosure. Such insulation having incorporated reflective heat shields may also comprise the thermal insulation 140 and heat shield 110 within the freeze-resistant nipple device 5.

(85) Optionally, a fill tube assembly 460 may be provided so that the reservoir container 50 can be filled without removal of the lids 360 and 310. Such a fill tube assembly comprises a feed-through at the reservoir container lid 360, and may comprise two parts, a male part 462 and a female part 465. In one preferred embodiment, the male part 462 is a Schedule 40 PVC pipe plug that has been drilled to provide a through hole, and the female part 465 is a Schedule 40 PVC pipe coupling. In one more-preferred embodiment, the male part 462 and female part 465 are of the slip fit type and are cemented together to firmly capture the lid 360, and a removable slip type Schedule 40 pipe plug is used to close the feed-through. Optionally, the feed-through may be sealed to the lid by RTV silicone cement, or by an intervening gasket, or by an elastomer grommet, or any of other common methods known in the art.

(86) To avoid a reduced pressure head in the interior 380 of the reservoir container 50 when lid 360 has an air tight seal to the container 50, a pressure relief hole in lid 360 or in the side wall 350 of the reservoir container is necessary. Such a pressure relief hole may comprise a hole in lid 360, which may also be used as a feed-through hole for a power cord for an immersible heater, for example of the aquarium type. A non-air-tight cap may be used to plug the hole to keep contamination and particulate out of the reservoir container. The pressure relief hole may also comprise one or more holes for attaching spacers to wall 350. Further, if the lid 310 forms an air tight seal to outer bucket 300, then a pressure relief hole in lid 310 or outer bucket 300 is necessary. Such a pressure relief hole may comprise the hole in the bottom of the outer bucket through which the nipple device 5 protrudes, or it may comprise the hole in the lid 310 through which the fill tube assembly 460 protrudes, or it may be another hole in lid 310 through which a heater power cord passes and which may have a non-air-tight plug to keep contamination and particulate out of the outer bucket.

(87) In one preferred embodiment, the reservoir container 50 may have protrusions 358 that are found on some plastic buckets for mounting a wire bail handle, and a wire bail handle is not used and a cord or string or similar means is attached to the protrusions to provide a means of lifting the reservoir container out of and placing the reservoir container into the outer enclosure.

(88) Mounting the waterer may be accomplished by any of several means that places the exposed surface 32 of the nipple valve at a height above the ground or floor that is convenient for the bird's actuation and use of the nipple valve. Examples of means of mounting include, but not as limitations, hanging from a hook, a shepherd's crook, a cable, a chain, fence posts, placement on a shelf, on stacked objects, on a bent rod support such as commonly used for supporting a potted plant, and by attaching support members or legs to the outer enclosure 300. In one preferred embodiment, the waterer is suspended by a wire bail handle comprising 302 and 304, which is attached to outer bucket 300 at protrusion 301. Such wire handles are common features of HDPE food grade buckets. Rope, cord, chain, or other means may also be used to suspend the waterer. In one more-preferred embodiment, the waterer is suspended by a wire bail handle comprising 302 and 304 and a chain 306. In one preferred embodiment, the waterer is mounted on a post that is partially embedded or driven into the ground or that is attached to a structure. An example of such a post is a metal u-tube fence post that is commercially available. A mounting support, such as a bolt may be attached to the post so that the waterer can sit on the protruding bolt of a support piece attached thereto. A chain, string, cord, rope, or the like may be used to hold the waterer against the vertical post. For posts that are not sufficiently stiff to avoid unacceptable torsion motion, one or more additional posts may be used to provide torsion stability. In one preferred embodiment, the waterer is placed on a shelf or stand that places the exposed surface 32 of the nipple valve at a desired height.

(89) The heat flux from the reservoir container may be estimated by the formalism of Eqns. 1-13. With an initial temperature T.sub.init, it is expected that the temperature in the reservoir T.sub.r will have a time dependence given by

(90) 0$\begin{array}{cc}{T}_r=T_0+\frac{P_h}{b}+\left[T_{\mathrm{init}}-T_0-\frac{P_h}{b}\right]\exp \left\{\frac{-t}{{}_0}\right\},& \left(17\right)\end{array}$
where P.sub.h is the power of a heater in the reservoir container,

(91) $b=\frac{{\mathrm{dQ}}_{\mathrm{total}}}{d\left(T_r-T_0\right)}$
is the slope of the heat loss as a function of temperature difference between the reservoir container interior and the exterior ambient temperature, and

(92) ${}_0=\frac{C_{p}V}{b}$
is the characteristic temperature decay time and where is the density of water, C.sub.p is the specific heat of water, and V is the volume of water in the reservoir container. The parameter b can be calculated by a fit of a linear function to the heat loss Q.sub.total=Q.sub.side+Q.sub.top+Q.sub.bottom+Q.sub.nipple where each of first three of these terms is the result of convective and radiative heat transfer in series with net transfer that is mainly by conduction through the insulation layers. The heat loss at the nipple assembly Q.sub.nipple, has been described above. In a conservative estimate of T.sub.r, the exterior surface of the outer bucket may be treated as being at the exterior ambient temperature T.sub.0.

(93) Shown in FIG. 17 are the calculated water temperature T ( C.), i.e., the reservoir temperature (denoted as T.sub.r in the above equations), as a function of time, t (hours), for an embodiment comprising a one gallon reservoir container 50 that is enclosed by a 2 gallon outer bucket as the outer enclosure 300 as in the embodiments of the waterer shown in FIGS. 12-15. Two cases are compared, one with an internal immersion heater in the interior 380 of the reservoir container 50, the other without a heater. In both cases, the initial temperature T=T.sub.init=43.24 C. (110 F.); the water volume is 1 gallon (3.8 liters); the exterior ambient temperature is T.sub.0=17.9 C. (0 F.), and the wind speed v.sub.w is about 8 mph. For the case with an internal immersion heater, three curves are shown in the figure. The uppermost corresponds to a heater power of P.sub.h=18 W. The second curve from the top corresponds to P.sub.h=15 W; the next lower curve, third curve from the top, corresponds to P.sub.h=10 W, which may be considered to be at the upper end of the range of low power heaters that is equal to about 10 W/gallon of reservoir. In these calculated curves, the heater power is turned on at t=0, and the curves asymptote to a steady state with water temperature T=23.3 C. (74 F.), 16.4 C. (62 F.), 5.0 C. (41 F.), which correspond to P.sub.h=18, 15, and 10 W, respectively. In experiments with an immersed heater in winter conditions comparable to the calculations, e.g., daytime high ambient temperature T.sub.0 of about 18 C. (0 F.) and a daily low (early morning) temperature of T.sub.0=21.7 C. (7 F.) and wind speed v.sub.w of about 23 mph with gusts to 31 mph, the water temperature asymptotes to about 23 C. (about 74 F.). In this case, because the heater is an aquarium heater and has an internal thermostat that has a fixed set point of about 25.4 C. (78 F.), the water temperature is experimentally observed to decay according to the unheated case until the set point temperature is reached, then the water temperature slowly cools to the asymptotic quasi-steady state of about 23 C. (about 74 F.) for which it is presumed that the heating power, P.sub.h=16.4 W (which may be considered to be in the range of medium power heaters), produced by the heater equals the power lost to the environment by the waterer. The experimental results are in reasonable agreement with the calculations in light of the approximations of the model and the non-steady ambient conditions. It appears that the variance of power loss between model and experiment is <10%.

(94) In the case without an internal immersion heater, the calculated reservoir water temperature is shown as the lowest curve (dot-dashed) in the figure, and a curve fit to the experimental data is shown as a curve (dot-dashed) slightly above the bottom curve. Typically, the experimental curve is within a few degrees of the calculation. It is seen that after a time t of about 9.5-10 hours, the experimentally measured water temperature T is between 5 C. (41 F.) and about 11 C. (51 F.); the temperature depending on the wind speed during the cooling time. The T=11 C. temperature resulted in calm conditions (wind nearly 0 mph), an ambient temperature T.sub.0 of about 9 C. (48.5 F.) results with wind speed v.sub.w about 9 mph, and the ambient temperature of 5 C. results with wind speed about 23 mph with gusts as great as 31 mph. In the latter conditions (windy), the nipple valve 30 is found to freeze when the reservoir water temperature is less than or equal to about 10 C. In contrast, the nipple is not frozen and provides liquid water when the reservoir water temperature is 6.5 C. with wind speed about 6-9 mph, and water temperature about 5 C. in lighter wind.

(95) Thus, it is found that such a waterer can deliver liquid water via the freeze-resistant nipple device 5 for a time t.sub.f of more than about 10 hours after an initial fill with warm (43 C., 110 F.) water in moderately windy ambient conditions with temperature about 18 C. (0 F.). With the use of a wind shield or placement in a lee wind condition to reduce the wind exposure of the exposed nipple surface 32, it may be reasonably expected that liquid water can be provided for more than 12 hours. In the case wherein an immersion heater is used, provision of warm liquid water has been demonstrated in ambient conditions of T=21.7 C. (7 F.) and wind speed of about 23 mph with gusts to 31 mph with P.sub.h of about 16.5 W Calculations show that with P.sub.h of about 10 W (which corresponds to 10 W/gallon for the one gallon reservoir of this example), a sufficient reservoir water temperature (e.g., about 10 C.) is maintained in extreme cold conditions (<18 C. (0 F.) and low wind speed or in a wind protected situation) so that in spite of the temperature drop along the heat pipe 10 and clamped sleeve 20 to the exposed surface 32 of the nipple, liquid water is provided by the nipple valve.

(96) In further tests of the waterer, it is found that without an immersion heater, the waterer can be filled with warm water less than 105 degrees F. and will provide liquid water via the freeze-resistant nipple valve assembly for at least 8 hours when the waterer is used in an ambient outside temperature of greater than or equal to 0 degrees F. The waterer with an immersion heater of about 15 to 17 Watts (which corresponds to 15 to 17 W/gallon for the one gallon reservoir of this example) can maintain water in the container at a temperature in the range of 50 to 80 degrees F., and deliver water at the exposed face of the nipple valve(s) at a temperature greater than 40 degrees F. when the waterer is used in an ambient outside temperature greater than 10 degrees F. The waterer can be filled with cool water in the range of 32 to 40 degrees F. and will provide water with temperature less than 90 degrees F. via the freeze-resistant nipple valve assembly for at least 8 hours when the waterer is used in an ambient outside temperature of less than or equal to 110 degrees F.

(97) In another preferred embodiment wherein the reservoir container 50 is a 2 gallon bucket and the outer bucket 300 is a 5 gallon bucket, the calculation predicts in the case where P.sub.h=0 (no heater) and ambient conditions at temperature equal to 18 C. (0 F.) and wind about 8 mph, that T.sub.r decays to 0 C. in about t.sub.f=10 hours. In the case with an immersion heater with P.sub.h=25 W, T.sub.r is about 12 C. after about 24 hours.

(98) Other embodiments may be obtained in light of the teachings herein. For example, the heat pipe 10 may be extended so as to comprise the clamped sleeve and to replace the plastic or stainless steel body, in whole or in part, and be clamped onto or press fit onto the annulus with exposed surface 32 so to conduct heat to the valve seat. In another embodiment, the heat pipe 10 may extend and be clamped or press fit onto a thin polymer layer on the annulus with exposed surface 32. In still another embodiment, the heat pipe 10 may be extended and be integral with the annulus with exposed surface 32.

(99) And, FIG. 18 provides a sectional view on a vertical plane of an alternate embodiment of a freeze-resistant nipple valve device with an actuator closed by a ball. The nipple valve 30 has its exposed surface 32 slightly below the outer shield 84 as shown. The exposed surface has a slightly beveled interior, here shown in cross section, the receives a ball 34 that serves as an actuator. An animal, bird, or poultry presses upon the ball and lifts it upwardly so that water or other liquid passes the ball for the animal, bird, or poultry to drink. When the animal, bird, or poultry leaves the ball, the pressure of water or other liquid within the heat pipe 10 presses the ball against the exposed surface, ceasing flow of water or other liquid from the invention.

(100) The preceding description refers to various embodiments. Within those embodiments, the Applicants foresee a water-tight seal made from an elastomer grommet, as at 83. The elastomer grommet includes one made of silicone rubber or other elastomer approved by the US Food and Drug Administration for contact with food and water. In a further alternate embodiment, the container as at 50, or outer bucket as at 300, has a lid as at 310, 360, proximate its handle, that is, generally opposite an installed nipple valve device, 30. The lid in this embodiment has an opening or tubular protrusion through which a user may fill the container. In a further alternate embodiment, the invention has its container, or outer bucket, constructed of high density polyethylene, HDPE, approved by the US Food and Drug Administration as a material safe for food contact and all water contact surfaces of the invention have a construction of materials suitable for potable water.

(101) From the aforementioned description, a freeze-resistant watering nipple device has been described. The freeze-resistant watering nipple device is uniquely capable of providing water, or other liquid, at a temperature below ambient temperature in a hot environment and of providing water, or other liquid, a temperature above freezing in a cold environment while the water, or other liquid, has a temperature tolerable to the drinking birds, poultry, or animals. The freeze-resistant watering nipple device and its various components may be manufactured from many materials, including but not limited to, those previously listed, polymers, copper, aluminum, stainless steel, ferrous and non-ferrous metals, their alloys, and composites.

(102) Various aspects of the illustrative embodiments have been described using terms commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. However, it will be apparent to those skilled in the art that the present invention may be practiced with only some of the described aspects. For purposes of explanation, specific numbers, materials and configurations have been set forth in order to provide a thorough understanding of the illustrative embodiments. However, it will be apparent to one skilled in the art that the present invention may be practiced without the specific details. In other instances, well known features are omitted or simplified in order not to obscure the illustrative embodiments.

(103) Various operations have been described as multiple discrete operations, in a manner that is most helpful in understanding the present invention, however, the order of description should not be construed as to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation. Moreover, in the specification and the following claims, the terms first, second, third and the likewhen they appearare used merely as labels, and are not intended to impose numerical requirements on their objects.

(104) The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to allow the reader to ascertain the nature of the technical disclosure. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

(105) As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. Therefore, the claims include such equivalent constructions insofar as they do not depart from the spirit and the scope of the present invention.