PRESSURE ACTUATED VALVES AND METHODS OF USE

Abstract

The present invention provides unique pressure actuated valves and related methods that may be used in applications where a plurality of fluid emission devices are provided on a plurality of lines containing fluid under pressure, in order to prevent fluid from escaping from the fluid emission devices until a consistent threshold or predetermined level of fluid pressure is obtained in the lines, without causing significant water pressure and/or flow loss through the valves. Valves of the present invention include a housing having an upper body and a lower body that may be coupled together to form an inner chamber, the lower body having an inlet in communication with a source of fluid under pressure, the upper body having an outlet in communication with a fluid emission device. A hollow movable fluid transmission piston is provided in the chamber for communicating between the inlet and outlet. The chamber formed between the upper and lower bodies may be provided with cup seals at opposite ends of the chamber to reduce friction and prevent fluid from entering therein, and a side air vent. A wider lower end of the piston is urged toward the lower housing body using a biasing mechanism, which pushes an O-ring at the lower end against a stop to prevent fluid from entering into the hollow center of the piston. When fluid with a sufficient pressure is provided from the source, it pushes the O-ring away from the stop and against the urging of the biasing member, allowing fluid to flow around the stop, through the center of the piston, and out through the upper body into the fluid emission device. The vent in the chamber allows air inside the chamber (surrounding the biasing mechanism) to escape so that there is no added air pressure within the chamber to be overcome by the fluid pressure.

Claims

1. A pressure actuated valve comprising: a. a housing having a fluid inlet, a fluid outlet, and a central chamber; b. a hollow movable piston traversing said chamber, said piston having a fluid inlet adjacent to said housing inlet and a fluid outlet adjacent to said housing outlet; c. a first U-cup seal between said housing inlet and said piston, and a second U-cup seal between said housing outlet and said piston for creating a seal between said piston and said chamber; d. at least one air vent in a wall of said chamber; e. a stop at said housing inlet, and a third seal on said movable piston for engagement with said stop for preventing fluid from flowing into said hollow piston when said third seal is engaged against said stop; and f. a biasing member on said piston for urging said third seal against said stop; wherein increased fluid pressure at said housing inlet causes said piston and said third seal to move said biasing member when a threshold pressure is reached, separating said stop from said third seal, and allowing fluid to enter into and pass through said hollow piston and exit through said housing outlet.

2. The valve of claim 1 wherein said housing comprises two parts which may be coupled together to form said chamber or uncoupled to allow access to said chamber.

3. The valve of claim 1 wherein said stop comprises a central head for temporary engagement with said third seal, and a plurality of arms having gaps between them through which fluid may flow, each of said arms being engaged with a cylindrical groove in said housing inlet for holding said stop in place.

4. The valve of claim 3 wherein said piston inlet further comprises a pair of annular rings defining a circumferential gap therebetween and wherein said first U-cup seal is provided in said circumferential gap.

5. The valve of claim 4 further comprising an annular guide slidably engaged around said piston outlet and wherein said second U-cup seal is provided around said piston between said annular guide and said housing outlet.

6. The valve of claim 1 wherein said housing inlet is in fluid communication with an irrigation water line and said outlet is in fluid communication with an emission device.

7. The valve of claim 2 wherein the length of said chamber may be adjusted by adjusting the distance between the coupled housing parts in order to change the amount of threshold water pressure needed to move said biasing member.

8. The valve of claim 7 wherein said housing parts comprise complementary threadings, and said threshold water pressure is adjusted by threading said housing parts into or out of each other.

9. The valve of claim 3 wherein said third seal comprises a ring shape to provide a watertight seal against the central head of said stop to prevent water from entering the hollow piston while in a sealed position.

10. The valve of claim 1 wherein said biasing member is a removable spring which encircles said piston.

11. A valve for an irrigation system comprising: a) a housing defining an internal chamber, said housing having an inlet end in fluid communication with an irrigation line, and an outlet end in fluid communication with a sprinkler head, said inlet end comprising a stop; b) a hollow piston inside said chamber, said piston having an inlet at the inlet end of said chamber, an outlet at the outlet end of said chamber, and a seal at said piston inlet operable to provide a watertight seal against said stop; c) a biasing member in said chamber, said biasing member being operable to bias said seal against said stop unless water in said inlet end reaches or exceed a threshold pressure; d) a first sealing member operable to provide a watertight seal between said piston inlet and said chamber to prevent water from entering said chamber at said inlet end; e) a second sealing member operable to prevent water from entering said chamber at said outlet end; and f) at least one vent in a wall of said chamber for allowing air to enter or exit said chamber.

12. The valve of claim 11 wherein the seal at said piston inlet is an O-ring, said first sealing member is a cup seal, and said second sealing member is a cup seal.

13. A method of using irrigation start valves comprising the steps of: a. providing an irrigation line having a plurality of openings thereon; b. installing a pressure actuated valve at each such opening, each of said pressure actuated valves comprising a housing having an inlet and an outlet, a sealed internal chamber, and a stop at said inlet; a hollow piston traversing said chamber, said chamber comprising an inlet end and an outlet end, said chamber being sealed at said inlet by a first sealing member, and sealed at said outlet by a second sealing member, wherein said piston is biased against said stop by said biasing member unless water in said inlet reaches a threshold water pressure; c. engaging a plurality of emission devices with the outlets of said plurality of pressure actuated valves; and d. providing water under pressure to said irrigation line such that when the threshold water pressure is reached, the piston is separated from the stop on each of the plurality of valves.

14. The method of claim 13 wherein an O-ring seal is provided on each piston that is urged against each stop by each biasing member.

15. The method of claim 13 wherein, each first sealing member is a cup seal, and each second sealing member is a cup seal.

16. The method of claim 13 further comprising the step of adjusting said threshold water pressure of at least one of said plurality of valves by adjusting a tension on the biasing mechanism of said at least one valve.

17. The method of claim 13 further comprising the steps of removing and replacing the biasing members on each valve in order to adjust the threshold water pressure needed to activate each valve.

18. The method of claim 13 wherein each housing comprises a first member threadably coupled to a second member, and comprising the additional step of unthreading the first and second members of each valve to increase the length of the chamber in order to reduce the threshold water pressure needed to separate the piston from the stop of each valve.

19. The method of claim 13 wherein each housing comprises a first member threadably coupled to a second member, and comprising the additional step of threading the first and second members of each valve together to decrease the length of the chamber in order to increase the threshold water pressure needed to separate the piston from the stop of each valve.

20. The method of claim 13 wherein the threshold water pressure is less than the pressure needed to fully operate each of said plurality of emission devices.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] FIG. 1A is an exploded partial cross-sectional view of an embodiment of a valve of the present invention.

[0050] FIG. 1B is an exploded cross-sectional view of an embodiment of a valve of the present invention.

[0051] FIG. 1C is a perspective exploded partial cross-sectional view of an embodiment of a valve of the present invention.

[0052] FIG. 1D is an exploded exterior side view of an embodiment of a valve of the present invention.

[0053] FIG. 2A is a partial cross-sectional view of an embodiment of a valve of the present invention.

[0054] FIG. 2B is a partial cross-sectional view of an embodiment of a valve of the present invention installed on an irrigation line and engaged with an emission device.

[0055] FIG. 2C is a cross-sectional view of an embodiment of a valve of the present invention showing the valve in a closed condition.

[0056] FIG. 2D is a cross-sectional view of an embodiment of a valve of the present invention showing the valve in an open condition.

[0057] FIG. 3A is a perspective view of an embodiment of an inlet segment (lower housing) of a housing of a valve of the present invention.

[0058] FIG. 3B is a perspective view of an embodiment of an outlet segment (upper housing) of a housing of a valve of the present invention.

[0059] FIG. 4 is a perspective view of an embodiment of a water passage piston of a valve of the present invention.

[0060] FIG. 5 is a perspective view of an embodiment of a piston guide of a valve of the present invention.

[0061] FIG. 6A is a side view of an embodiment of a stop of a valve of the present invention.

[0062] FIG. 6B is a top view of an embodiment of a stop of a valve of the present invention.

DETAILED DESCRIPTION

[0063] Reference will now be made in detail to certain embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in reference to these embodiments, it will be understood that they are not intended to limit the invention. To the contrary, the invention is intended to cover alternatives, modifications, and equivalents that are included within the spirit and scope of the invention. In the following disclosure, specific details are given to provide a thorough understanding of the invention.

[0064] Referring to FIGS. 1A-1D, it is seen that the illustrated valve 100 includes a housing 110 which may be made of two parts 110a and 110b which may be coupled or joined together to form the entire housing 110. Housing 110 is provided with a fluid inlet 111 which may be placed in fluid communication with a fluid source, and a fluid outlet 115 which may be placed in fluid communication with an emission device. The first or lower part of the housing 110a is designed to engage at 112 with a water source such as an irrigation supply line. The second or upper part of the housing 110b is designed to engage at 116 with a fluid emission device such as a sprinkler or sprinkler head 191. The engagement 112 of the first part 110a may comprise a threading complementary to a threading of a connector of an irrigation line 190. The attachment mechanism 116 of the second part 110b may comprise a threading complementary to a threading of the emission device 191 (see FIG. 2B).

[0065] When coupled together as shown in FIGS. 2A-2D, housing 110 defines an internal chamber 140. A hollow water passage piston 130 nested within the chamber 140, the piston 130 comprising an inlet end 131 and an outlet end 132. Chamber 140 is sealingly separated from the inlet 111 using a first sealing member 160, and chamber 140 is sealingly separated from the outlet 115 using a second sealing member 165. Sealing members 160 and 165 are preferably cup seals having angled annular edges, and may flare out in a frustoconical manner away from the interior of chamber 140. In the illustrated embodiments, as shown in FIG. 1, a first (lower) seal 160 may flare out toward inlet 111, and a second (upper) seal 165 may flare out toward outlet 115. The outer edges of seals 160 and 165 are designed to sealingly engage, respectively, the internal cylindrical wall 117 of the inlet 110 and the internal cylindrical wall 143 of the outlet 115. It is to be appreciated that in some embodiments, the shape of seal 165 is similar to that of seal 160, as shown in FIG. 1C. The inner edge of lower seal 160 is designed to sealingly engage a lower peripheral edge of piston 130, preferably at a circumferential groove 135 at an inlet end 131 of piston 130. The inner edge of upper seal 165 is designed to sealingly engage a peripheral edge 133 of the outlet end 132 of piston 130. The flared cup seals have less surface contact with the respective inside cylindrical walls of the chamber than O-rings would, thereby reducing friction and reducing the potential for the seals to get stuck against the walls which might prevent the piston from reciprocating. The seals also help prevent impurities such as sand or other materials from entering chamber 140 where they could cause malfunctions or damage to the piston 130 and/or biasing member 150 inside the chamber.

[0066] Piston 130 has a generally cylindrical configuration, and is deployed inside chamber 140 and has a hollow central bore 161 leading from an inlet end 131 to an outlet end 132 of piston 130. The cylindrical inlet end 131 of piston 130 is wider than the cylindrical outlet end 132, and may include a terminal ring 137. Ring 137 may include an internal recess 138 for receiving an O-ring 136. Piston 130 may also include a second ring 139 near the inlet end defining a circumferential recess or groove 135 into which seal 160 may be engaged. Sandwiching seal 160 in recess 135 between ring 137 and ring 139 prevents seal 160 from sliding up and down along piston 130 as it reciprocates inside chamber 140. The outlet end 132 of piston 130 slidably extends through a guide ring or washer 180. Guide ring 180 is designed to engage an annular shoulder 142 of a cylindrical opening in housing 110b. Cup seal 165 is provided in a smaller cylindrical opening 143 adjacent to shoulder 142, and is held in place by guide ring 180.

[0067] A movable stop 170 is provided at the inlet end of housing 110a adjacent to movable O-ring seal 136. Stop 170 includes a plurality of legs 172 defining openings between them through which fluid may pass when the valve is open. Stop also includes a central section or head 171 which may be temporarily sealingly engaged with seal 136. The central section 171 may comprise a frusto-conical shape, wherein the side of the cone may contact the passage seal 136, forming a watertight seal therewith. The plurality of support arms 172 may support the central member 171 against the biasing force of the biasing mechanism 150. Each support arm 172 has an edge 177 that engages a shoulder 113 of the inlet 111, securing stop 170 in place within a circumferential groove 114 in the inner surface 117 of the housing 110. By this engagement of edges 177 in groove 114, stop 170 is prevented from moving toward piston 130 when fluid pressure increases, and from moving away from piston 130 when fluid pressure decreases.

[0068] Biasing member or spring 150 is provided around the body of piston 130. A lower end 151 of spring 150 is engaged against an inside edge 132 of ring 139, and an upper end 152 of spring 150 is engaged against an inner edge of guide ring 180. When housing parts 110a and 110b are coupled together around the piston and spring assembly (which includes piston 130, spring 150, stop 170, O-ring 136, lower seal 160, guide ring 180 and upper seal 165), spring 150 urges piston 130 and O-ring 136 against the head 171 of stop 170. This creates a seal between the head 171 of stop 170 and O-ring 136, preventing fluid from passing through the inlet end 131 into bore 161 of piston 130. See FIG. 2B. Thus, piston 130 is biased against said stop 170 by said biasing mechanism 150 until fluid pressure in said inlet 111 is greater than the biasing force of said spring 150. When fluid pressure reaches or exceeds the biasing force of spring 150, piston 130 is pushed away from inlet 111 causing O-ring 136 to be separated from the head 171 of stop 170. This separation occurs because edges 177 of arms 172 of stop 170 are engaged with groove 114 preventing stop 170 from moving. The separation of seal 136 from stop 170 allows fluid to flow between arms 172 of stop 170 and into the hollow central bore 161 of piston 130. The fluid then exits from the piston at outlet 132 and passes through outlet 115 of housing 110b to fluid a emitter or sprinkler 191.

[0069] It is to be appreciated that it is possible to change the threshold water pressure needed to activate the valve by using different springs 150 with different strengths. A stronger spring will require more (higher) water pressure to activate the valve than a weaker spring. It is preferred that all springs in all valves in a given irrigation system have the same strength so that the same water pressure is needed to open all of the valves simultaneously. In alternative embodiments, the threshold water pressure needed to activate the valve may be changed by changing the length of the chamber. This may be accomplished by partially threading or unthreading the housing parts 110a and 110b. This would have the effect of shortening or lengthening the distance covered by the spring.

[0070] Reducing this distance would increase the amount of water pressure needed to overcome the spring, and expanding this distance would reduce the amount of pressure needed. Valves having chambers of different lengths may also be used, either with or without changing the springs, to adjust the amount of water pressure needed for activation.

[0071] The housing 110 may comprise one or more vents 141 for equalizing air pressure inside chamber 140 of housing with air pressure outside the housing 110. Each vent 141 may comprise a passage traversing the wall of the housing 110, from the inner surface 117 of the housing to the outer surface 120. Each vent 141 may be operable to allow air to pass from the chamber 140 to the atmosphere and vice versa.

[0072] As noted above, housing 110 may be operable to be separated into an inlet segment 110a and an outlet segment 110b. The housing 110 may thus allow access to the chamber 140 and to the internal components of the valve 100 (e.g., the water passage 130, the sealing members 160, 165, the biasing mechanism 150, the inner end of the vent 141, and guide 180) as well as stop 170 and seal 136. The inlet segment 110a may comprise a threading 118 having a shape complementary to a threading 119 of the outlet segment 110b. The complementary threadings 118, 119 may allow for adjustment of the overall length of the housing 110 and therefore adjustment of the length of the chamber 140 which is defined in part by the housing 110. The valve 100 of the present invention may thus allow for adjustment of the load on the biasing mechanism 150 housed in the chamber 140, and thereby adjust the threshold water pressure which is required to overcome the force of the biasing mechanism 150 to actuate the valve 100.

[0073] The biasing mechanism 150 may comprise a spring having a first end 151 in contact with a chamber side 134 of the inlet end 131 of the water passage 130, and a second end 152 which is in contact with the passage guide 180 engaged with the outlet segment 110b of the housing 110. Threading the outlet segment 110b further into the inlet segment 110a may therefore increase the load on the spring 150, thereby increasing the biasing force on the chamber side 134 of the inlet end 131. Conversely, unthreading the outlet segment 110b may reduce the load on the spring 150, reducing the biasing force on the chamber side 134 of the inlet end 131. Thus, threading the outlet segment 110b into or out of the inlet segment 110a may also increase or decrease, respectively, the threshold water pressure required to actuate the valve 100.

[0074] The water passage may comprise an inlet end 131 and an outlet end 132. The inlet end may 131 comprise a circumferential groove 135 having a shape complementary to a shape of the first sealing member 160, which may securely nest within the circumferential groove 135, maintaining watertight contact with both the inlet end 131 and an inner surface 117 of the housing 110. The inlet end 131 may comprise an opening, the opening providing fluid communication through the water passage 130 to the outlet end 132. The opening may comprise the passage seal 136. The passage seal 136 may be substantially ring-shaped with a circular cross section. The passage seal 136 may comprise an elastic material operable to withstand compression between the inlet end 131 and the stop 170 while maintaining watertight contact with each.

[0075] The outlet end 132 of the piston 130 may comprise a substantially smooth outer surface 133 having a substantially cylindrical shape. The outer surface 133 may be operable to maintain watertight contact with a surface of a second sealing member 165 positioned in the outlet segment 110b. The distal-most edge of the outlet end 132 may traverse and extend past the second sealing member 165, into the outlet 115 of the housing 110.

[0076] The passage guide 180 may be operable to control a position of the outlet end 132 of the piston 130. The passage guide 180 may comprise a collar nested in a shoulder of the outlet segment 110b, the collar having an inner diameter substantially similar to an outer diameter of the outlet end 132, and having an outer diameter substantially similar to an inner diameter of a first tier 142 of the shoulder of the outlet segment 110b. The second sealing member 165 may be nested in the second tier 143 of the shoulder area and may be operable to maintain watertight contact with both a surface of the second tier 143 and the outer surface 133 of the outlet end 132, thus preventing water from passing from the outlet 115 into the chamber 140. The passage guide 180 may be installed over the second sealing member 165, such that the second sealing member 165 is secured in the second tier 143 by the passage guide 180. The second end 152 of the spring may provide a force against the passage guide 180, securing the passage guide 180 in the first tier 142 of the shoulder area.

[0077] The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.