Upright fire protection sprinkler
11440032 · 2022-09-13
Inventors
- Manuel R. Silva, Jr. (Cranston, RI)
- Bernhard Abels (Tallahassee, FL, US)
- Kenneth Robert Brown (Chesterfield, MO, US)
- Stefan Vaeth (Wertheim, DE)
Cpc classification
B05B1/265
PERFORMING OPERATIONS; TRANSPORTING
A62C3/002
HUMAN NECESSITIES
International classification
Abstract
A fire protection sprinkler including a frame body having an inlet, an outlet, defining an internal passageway extending between the inlet and the outlet along a sprinkler axis. A dome shaped deflector member is centered, axially aligned with the sprinkler axis, and spaced from the outlet. The deflector member has an outer surface and an inner surface that preferably includes: a peripheral region, a central region and an intermediate region. The intermediate region includes a primary deflecting surface, and a secondary deflecting surface that is surrounded by the primary deflecting surface. The deflector member provides for generation of a non-circular spray pattern defined by four zones of fluid density concentrically formed about the sprinkler axis.
Claims
1. An automatic upright fire protection sprinkler comprising: a frame having a body having an inlet, an outlet, and an internal passageway extending between the inlet and the outlet along a sprinkler axis, the outlet defines an orifice diameter; a sealing assembly disposed in the outlet; a heat-responsive trigger to maintain the sealing assembly in the outlet; and a deflector member centered, axially aligned with the sprinkler axis, and spaced from the outlet of the internal passageway, the deflector member having an outer surface and an inner surface including: a peripheral region, a central region and an intermediate region between the peripheral and central regions, the peripheral region defines a peripheral edge that circumscribes the sprinkler axis and defines a maximum deflector diameter, the peripheral region and the central region are axially spaced apart along the sprinkler axis to define a total deflector height, the intermediate region including a primary deflecting surface, a secondary deflecting surface and a transition from the primary deflecting surface to the secondary deflecting surface, the primary deflecting surface is defined by a spherical radius of curvature with a center disposed along the sprinkler axis, the transition defining a perimeter about the secondary deflecting surface such that the secondary deflecting surface is surrounded by the primary deflecting surface, the deflector member defining at least one of: an orifice diameter-to-spherical radius ratio ranging from 0.65-0.75; a maximum deflector diameter-to-spherical radius ratio ranging from 1.90-2.0; a maximum deflector diameter-to-total deflector height ratio ranging from 3.45-1.55; and a spherical radius-to-total deflector height ratio ranging from 1.80-1.85.
2. The upright sprinkler of claim 1, wherein the perimeter about the secondary deflecting surface is elongated defining a width and a length greater than the width, the length extending toward the sprinkler axis.
3. The upright sprinkler of claim 1, wherein the secondary deflecting surface and perimeter includes four secondary deflecting surfaces each defined by a perimeter, each secondary deflecting surface and perimeter extending along one of two perpendicular planes dividing the deflector member into substantially equal part quadrants such that the four secondary deflecting surfaces are angularly spaced apart at 90 degrees from one another.
4. The upright sprinkler of claim 3, wherein each of the four secondary deflecting surfaces includes radial inner ends diametrically opposed about the central region spaced at a linear distance of about 1.3 inches from one another.
5. The upright sprinkler of claim 2, wherein the secondary deflecting surface and its perimeter define an axial length ranging from 0.5-0.6 inch and a substantially v-shaped groove with respect to a perimeter axis along which the perimeter extends with a maximum width of about 0.2 inch and a radius of curvature of 0.08 inch.
6. The upright sprinkler of claim 3, wherein the primary deflecting surface defines a peripheral junction contiguous with the peripheral region and an internal junction contiguous with the central region, the perimeter of each secondary deflecting surface being disposed between the internal junction and the peripheral junction.
7. The upright sprinkler of claim 5, wherein the intermediate region defines a peripheral junction contiguous with the peripheral region, the peripheral junction defining an internal diameter to define a maximum deflector diameter-to-internal diameter ratio ranging from 1.05-1.1.
8. The upright sprinkler of claim 5, wherein the secondary deflecting surface is a continuous elongate formation extending toward the sprinkler axis to define an arcuate profile that is substantially continuous and parallel to the radius of curvature of the primary deflecting surface at a radial depth from the center of the spherical radius of curvature that is greater than the spherical radius of curvature.
9. The upright sprinkler of claim 5, wherein the maximum deflector diameter-to-spherical radius ratio ranges from 1.90 to 1.95.
10. The upright sprinkler of claim 5, wherein the spherical radius of curvature of the primary deflecting surface is 1.6 inches, the maximum deflector diameter being about 3 inches.
11. The upright sprinkler of claim 1, wherein the maximum deflector diameter ranges from 3.0-3.1 inches.
12. The upright sprinkler of claim 5, wherein the total deflector height is about 0.875 inch.
13. The upright sprinkler of claim 1, wherein the intermediate region defines a peripheral junction contiguous with the peripheral region, the peripheral region including a plurality of spaced apart tines, each tine being bent from the peripheral junction to define a bend line and an included angle with respect to a vertical parallel to the sprinkler axis.
14. The upright sprinkler of claim 13, wherein the included angle is 8°-10°, each tine defining a length of 0.25-0.3 inch and including a pair of lateral edges which extend to terminate at a substantially linear edge that is disposed contiguously with and substantially perpendicular to each of the lateral edges, the substantially linear edges defining a discontinuous peripheral edge of the deflector member about the sprinkler axis, the plurality of tines being equiangularly spaced apart with adjacent lateral edges spaced apart by an angle of fifteen degrees with each tine defining a width of 0.15 inch.
15. The upright sprinkler of claim 14, wherein the discontinuous peripheral edge of the deflector member is axially spaced about 1.75 inches from the outlet of the frame.
16. The upright sprinkler of claim 1, wherein the central region is a substantially planar surface extending perpendicular to the sprinkler axis and including a central hole for receiving and engaging a planar shoulder formed about the distal end of the frame, the central region defining a diameter of about 0.75 inch at an internal junction of the intermediate region contiguous with the central region.
17. The upright sprinkler of claim 1, wherein the deflector member is fastened to the frame by a retention member and a threaded member, the retention member defining an annular deflector engagement surface for engaging the outer surface of the deflector member, the annular deflector engagement surface having an inner diameter and an outer diameter to distribute a holding force from a threaded engagement between the retention member and the threaded member to statically hold the deflector member in place under a full load of fluid discharge delivered at a discharge pressure of 50 psi or greater to the inlet.
18. The upright sprinkler of claim 17, wherein the retention member and deflector member define a ratio of the maximum deflector member diameter-to-retention member outer diameter ratio of about 2.5:1.
19. The upright sprinkler of claim 1, wherein the outlet defines an outlet diameter, and the deflector member and outlet define a ratio of the maximum deflector member diameter-to-outlet diameter ratio of 2.6:1.
20. The upright sprinkler of claim 1, wherein the internal passageway and the outlet define a nominal K-factor of at least 33.6, where the K-factor equals an average flow of water in gallons per minute through the internal passageway divided by a square root of pressure of water fed into the inlet of the internal passageway in pounds per square inch gauge.
21. The upright sprinkler of claim 1, wherein the outlet defines an outlet diameter ranging from 1.15-1.2 inches.
22. The upright sprinkler of claim 21, wherein the internal passageway defines an orifice diameter of 1.05-1.1 inches.
Description
DESCRIPTION OF DRAWINGS
(1) The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary embodiments of the invention and, together with the general description given above and the detailed description given below, serve to explain the features of the exemplary embodiments of the invention.
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(16) Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
(17) Referring to
(18) The frame 12 preferably includes a pair of support arms 32, 34 extending generally distally away from opposite sides of and more preferably diametrically opposed about the outlet end 20 of the body 14 to converge toward the sprinkler axis A-A and form an apex 36 at the distal end of the frame 12. The apex 36 is preferably axially aligned with axis A-A and axially spaced from the outlet end 20 of the internal passageway. A preferred deflector 100 is supported by and preferably fastened to the apex 36 so as to be axially spaced from the outlet end 20 to distribute a flow of fire-fighting fluid, e.g., water, from the outlet end 20 about the sprinkler assembly 10. The deflector 100 is preferably centrally and coaxially aligned with the sprinkler axis A-A. At the distal end, the apex 36 defines an end face that includes a central post about which the deflector 100 is disposed. The distal end of the apex 36 defines a maximum width or diameter which preferably measures about 0.7 inches. In one aspect of the preferred sprinkler assembly 10, the preferred pair of arms 32, 34 are disposed about the sprinkler body 14 in a plane P1 which bisects the deflector 100.
(19) Referring to
(20) As seen in
(21) In a preferred embodiment, the intermediate region 102c is preferably defined by a primary deflecting surface 104. A preferred embodiment of the primary deflecting surface 104 is defined by a spherical radius of curvature R1 of about 1.5 inches and more preferably 1.6 inches to define the domed geometry, with the center of curvature preferably located along the central axis of the deflector member 100, which is coaxially aligned with the sprinkler axis A-A. As used herein, the term “about” is understood as being within a range of normal engineering or manufacturing tolerance of the stated value. Unless otherwise clear from context, all numerical values provided herein are modified by the term about. With reference to
(22) The preferred peripheral region 102a of the deflector member 100 includes a plurality of spaced apart tines 110. Each tine 110 defines a preferred length L2 of ranging 0.25-0.3 inch and is more preferably about 0.28 inch extending from the preferred peripheral junction 104b of the intermediate region 102c. Each tine 110 is preferably bent from the peripheral junction 104a to define a bend line and a preferred included angle β of 8°-10° and more preferably 8° with respect to a vertical parallel to the sprinkler axis A-A, as seen for example in
(23) In the preferred embodiment of the deflector 100 of
(24) In a preferred embodiment, the intermediate region 102c includes one or more secondary deflecting surfaces 106 and a transition from the primary deflecting surface 104 to the secondary deflecting surface 106. As shown in
(25) As seen in
(26) The one or more secondary deflecting surfaces may be alternately defined by variation in one or more characteristics of the secondary deflecting surfaces 106. For example, each of the secondary deflecting surfaces 106a, 106b, 106c, 106d can be discontinuous as being defined by a plurality of formations extending along or in the direction of the axes, X-X, Y-Y. Further in the alternative, the secondary deflecting surface can be defined by a formation in which its depth, i.e., radius of curvature R2, varies over the length of the formation relative to the primary deflecting surface. The width W1 of the secondary deflecting surfaces 106 can vary over the length of the formation. Alternative embodiments of the secondary deflecting surfaces 106 can extend over a path that intersects the bisecting planes P1, P2 several times in a zig-zag like fashion. The secondary deflecting surfaces 106 of the preferred embodiments of the deflector member 100 extend linearly along axes, X-X, Y-Y, which intersect a tine of the deflector. Alternative embodiments of the secondary deflecting surfaces 106 could extend along an axis that extends to the periphery of the deflector between tines.
(27) The deflector member 100 is preferably formed from a planar blank member of uniform thickness preferably about 0.05 inch thick, but any other thickness can be used provided the deflector member can be formed and provide sufficient rigidity under a discharged fluid load as described herein. As shown, the preferred deflector member 100 is formed such that the outer surface of the deflector member 100 is the mirror image or impression of the inner surface of the deflector member 100. Accordingly, the outer surface of the deflector member 100 can be a function of the formation of the inner surface of the deflector member 100. The deflector member 100 however can be alternately formed such that the outer surface is different and/or independent of the formation of the inner surface. Accordingly, the outer surface of the deflector member 100 can define a variable profile over its surface including for example, one or more projections, surface treatments, or surface indentions or grooves.
(28) The deflector 100 is preferably mechanically fastened to the sprinkler frame 12. Referring to
(29) In a preferred embodiment of the sprinkler assembly 10, the deflector 100 is secured to the sprinkler frame 12 by a retention member 50 and a threaded member 52. The threaded member 52 forms a threaded engagement with the retention member 50 and the apex 36 of the frame with the deflector 100 disposed between the retention member 50 and the distal planar shoulder 40 of the frame 12. The retention member 50 defines a preferably annular deflector engagement surface 54 for engaging the outer surface of the deflector 100. The deflector engagement surface 54 of the retention member is preferably annular in shape having an inner diameter D1 of about 0.7 inch and an outer diameter D2 of about 1.2 inches. Moreover, the inner diameter D1 is preferably at least as great as the maximum diameter of the apex 36 to define a preferred minimum ratio of retention member inner diameter-to-maximum apex diameter of 1:1. The area of the engagement surface 54 of the retention member 50 distributes a holding force from the threaded engagement between the retention member 50 and threaded or screw member 52 to statically hold the deflector 100 in place under a full load of fluid discharge delivered at a discharge pressure of 50 psi or greater. The preferred retention member 50 and deflector 100 define a preferred maximum deflector diameter Dia1-to-retention member diameter D2 ratio of about 2.5:1. The outer surface of the retention member 50 is shown as substantially frustoconical. However, it should be understood that the outer surface of the retention member 50 can define an alternate profile that includes, for example, tool engagement flats or a more cylindrical profile provided the retention member 50 can secure the deflector 100 to the frame 12.
(30) The preferred deflector 100 is secured to the frame 12 to preferably orient the secondary deflecting surfaces 106a, 106b, 106c, 106d relative to the frame arms 32, 34. More specifically, as seen in
(31) Referring to the cross-sectional view of the sprinkler assembly 10 in
(32) The internal passageway 16 defines preferred discharge characteristics of the sprinkler 10. A sprinkler's discharge characteristics can be identified by a nominal K-factor which is defined as an average flow of water in gallons per minute through the internal passageway divided by a square root of pressure of water fed into the inlet end of the internal passageway in pounds per square inch gauge (psig): Q=K√{square root over ( )}P where P represents the pressure of water fed into the inlet end of the internal passageway through the body of the sprinkler, in pounds per square inch gauge (psig); Q represents the flow of water from the outlet end of the internal passageway through the body of the sprinkler, in gallons per minute (gpm); and K represents the nominal K-factor constant in units of gallons per minute divided by the square root of pressure expressed in psig. Nominal K-factors (with the K-factor range shown in parenthesis) can include: (i) 14.0 (13.5-14.5) GPM/(PSI).sup.1/2; (ii) 16.8 (16.0-17.6) GPM/(PSI).sup.1/2; (iii) 19.6 (18.6-20.6) GPM/(PSI).sup.1/2; (iv) 22.4 (21.3-23.5) GPM/(PSI).sup.1/2; (v) 25.2 (23.9-26.5) GPM/(PSI).sup.1/2; (vi) 28.0 (26.6-29.4) GPM/(PSI).sup.1/2; (vii) 33.6 (31.9-35.28) GPM/(PSI).sup.1/2; and 36.4 (34.6-38.2) GPM/(PSI).sup.1/2.
(33) The fire protection sprinkler 10 and internal passageway 16 define a preferred nominal discharge coefficient or K-factor of greater than about 16.0. In preferred embodiments, the nominal K-factor can be between about 16.8 and about 28.0, preferably between about 22.4 and about 33.6, more preferably between about 25.2 and about 36.4, and most preferably is a nominal K-factor of 33.6 GPM/(PSI).sup.1/2. For the preferred sprinkler assembly 10 and desired fluid distribution densities, it has been determined that the sprinkler assembly 10 defines a minimum working pressure of 30-50 psi. for a preferred working flow of about 240 gpm and more preferably 238 gpm.
(34) The preferred means for generating a desired spray pattern is preferably defined by the inter-dimensional relationships of two or more dimensional characteristics of the deflector and sprinkler frame. The desired spray pattern is effective in the protection of storage occupancies and commodities. The preferred means includes a preferred deflector characterized by at least one of: (i) an orifice diameter-to-spherical radius ratio (ORFD:R1) ranging from 0.65-0.75; (ii) a maximum deflector diameter-to-spherical radius ratio (Dia1:R1) ranging from 1.90-1.95; (iii) a maximum deflector diameter-to-total deflector height ratio (Dia1:DH) ranging from 3.45-3.55; and (iv) a spherical radius-to-total deflector height ratio (R1:DH) ranging from 1.80-1.85. Alternatively or additionally, the means is defined by a preferred maximum deflector diameter-to-outlet diameter ratio (Dia1:OD) of about 2.6:1; and/or the orifice defines a preferred maximum deflector diameter-to-orifice diameter ratio (Dia1:ORFD) of about 2.8:1. In another preferred aspect, the preferred means of the deflector 100 includes a ratio of the maximum deflector diameter Dia1-to-spherical radius R1 to be about 2:1. Alternatively or additionally, the deflector 100 defines a maximum deflector diameter-to-deflector height ratio (Dia1:DH) of about 3.5:1.
(35) Generally a desired spray pattern is non-circular, defined by a perimeter with two or more linear edges centrally or equidistantly disposed about the sprinkler 10. More preferably, the spray pattern is substantially rectangular and more preferably a square formed preferably within a ten foot-by-ten foot (10 ft.×10 ft.) perimeter centered about the sprinkler axis A-A in a plane preferably located about three-five and more preferably four feet below the peripheral region 102a of the deflector 100 and perpendicular to the sprinkler axis A-A. Even more preferably, the preferred spray pattern includes a high concentration of fluid distribution in the central area of the spray pattern with decreasing fluid distribution in the lateral outward direction away from the sprinkler axis A-A toward the perimeter of the substantially square pattern. The perimeter of the spray pattern is preferably defined by a distribution that is sufficient to effectively address a fire. Moreover, in one preferred aspect of the spray pattern, little to no fluid is distributed at or beyond six feet (6 ft.) from the sprinkler axis. Additionally, in the areas proximate to or along the edges of the preferably substantially square pattern, the fluid density preferably decreases in directions from the center of the edge toward the corners of the perimeter. In a preferred spray pattern, the areas adjacent and outside the corners of the ten-by-ten foot perimeter receive little to no fluid from the spray pattern.
(36) To evaluate the performance the preferred means to generate a desired spray pattern, the sprinkler assembly can be installed in a fluid distribution test arrangement as shown in
(37) Shown in 4B is a layout of the collection pans each identified by its (X,Y) coordinate relative to the sprinkler 10. For example, collection pan (3,4) is the pan located three feet along the X-axis and four feet down the Y-axis. The collection pans 60 are grouped into concentric substantially rectangular zones of a desired spray pattern. Zone 1 (Z1) is defined by the four collection pans (1,1); (1,2); (2,1); (2,2) below the sprinkler 10 which collect the central portion of the spray pattern. Zone 3 (Z3) is defined by the collection pans at the perimeter of the spray pattern (5,1); (5,2); (5,3); (5,4); (1,5) (2,5); (3,5); (4,4); and (5,5) in which collection pan (5,5) is located at the corner of the preferred spray pattern. Accordingly, the collection pans of Zone 3 (Z3) define the outline of a preferred non-circular and substantially square spray pattern. Zone 2 (Z2) is defined by the collection pans 60 between Zone 1 (Z1) and Zone 3 (Z3). Zone 4 (Z4) is defined by the group of collection pans surrounding the preferred perimeter Z3. Generally, Zone 4 (Z4) preferably has a low concentration in fluid distribution corresponding to a drop in fluid distribution at the perimeter of the preferred spray pattern in Zone 3.
(38) Generally, the preferred spray patter is bound by a non-circular perimeter defined by the L-shaped Zone 3 (Z3) of the quadrant. Zone 4 preferably amounts to less than five percent and is preferably zero of the total fluid distribution or density of the spray pattern. The water distribution of the spray pattern at the collection pan (5,5) preferably reveals a distinct corner-like edge with the adjacent pans in the fourth zone preferably having no fluid collected therein. The preferred spray pattern preferably includes a concentration of fluid density in the central portion of the spray pattern such that 30% to 35% of the total distribution is preferably within Zone 1 (Z1) and centered beneath the sprinkler 10. Moreover, of the four distribution pans shown of Zone 1 (1) quadrant, three of the pans would collect at a density greater than any pan in the other three zones. The distribution density preferably decreases radially from the sprinkler 10 and at the perimeter of the preferred spray pattern with the distribution density in Zone 3 (Z3) preferably ranging from 40-60% of the density of Zone 1 (Z1) and more preferably ranging from 50-60% and even more preferably is about 58%.
(39) To control the discharge of fluid from the frame outlet 20, the preferably “automatic” sprinkler assembly 10 includes a preferred heat-responsive trigger 200 or any suitable trigger, such as for example, an electrically actuated trigger. The preferred thermally responsive trigger 200 could be any one of a bulb-type trigger, as seen for example, in
(40) The heat-responsive trigger 200, 200′ and its actuation is defined by its nominal temperature rating and Response Time Index, or RTI. The trigger 200 is configured to actuate at or define a preferred nominal temperature rating of 286° F. and define a preferred RTI of 135 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2) to about 160 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2). The trigger may have another nominal temperature rating provided it is suitable for the hazard, occupancy or storage being protected, including, for example as defined under NFPA 13: (i) ordinary 135° F.-170° F.; (ii) intermediate 175° F.-225° F.; (iii) high 250° F.-300° F.; (iv) extra high 325° F.-375° F.; (v) very extra high 400° F.-475° F.; and (vi) ultra high 500° F.-575° F. Moreover, the heat-responsive trigger 200 can define alternate ranges of RTI, which can range from at least 130 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2) to 160 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2), preferably at least 135 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2) to about 160 meter sec/m.sup.1/2s.sup.1/2), more preferably 150 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2) to about 160 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2), and even more preferably 160 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2). Further in the alternative, the RTI can range to 50 meter.sup.1/2sec.sup.1/2 (m.sup.1/2s.sup.1/2) or less so as to be a “quick” or “fast” response type sprinkler.
(41) Preferred embodiments of the sealing assembly 300 are shown in
(42) Alternatively or additionally, an embodiment of the sprinkler assembly can include a spring member 312 surrounding the body 302 to facilitate ejection of the annulus and body upon thermal actuation of the trigger 200. The spring member 312 can include a first end 312a and an opposite second end 312b, as seen in
(43) As shown in
(44) The preferred bulb 202 further preferably defines a bulb length BL between the first and second ends 202a, 202b. The passageway 16 of the sprinkler frame 12 defines a passageway length PL that extends between the inlet end 18 and the outlet end 20. In a preferred embodiment of the sprinkler assembly 10, the bulb length BL is greater than the passageway length PL. In one preferred embodiment of the bulb 202, the bulb length BL is preferably greater than one inch and is more preferably about 1.5 inches (40 mm.). The passageway length PL preferably ranges from about 1.5 inches to about 1.3 inches, is preferably about 1.25 inches and is more preferably 1.28 inches. The glass bulb 202 includes an internal surface to define a inner space for holding the thermally responsive liquid. Accordingly, the bulb 202 preferably defines a wall thickness between the outer and inner surfaces of the bulb. The bulb 202 preferably defines a maximum wall thickness that is less than the difference between the bulb length BL and the passageway length PL. In one preferred embodiment of the bulb 202, the maximum wall thickness is about 1 mm. to define a preferred ratio of maximum thickness to bulb length which can range from 1:30 to about 1:40.
(45) In an alternate embodiment of the sprinkler assembly 10, the trigger 200′ can be embodied as a link assembly 212 having a strut 212a, a hook or lever 212b and thermally responsive link 212c. The link assembly 212 is similar to the thermally responsive trigger assembly shown and described in U.S. Pat. No. 8,522,888. In the unactuated state, the strut 212a has a first end 214a inserted or engaged with an appropriately sized groove 304′ formed in the first surface 302a of the closure body 302. The lever 212b can be fixedly connected at one end to a generally conical end 52′a of an alternate threaded member 52′ via a second notch 216a. The hook 212b is coupled to the preferably heat responsive link 212c at the other end. The link 212c preferably includes two metallic links joined face to face by a thin layer of fusible material. The fusible material can be calibrated to change from a solid state to a liquid state as a function of a fixed temperature or a range of temperatures to provide the desired thermal rating and responsiveness previously described. The lever 212b and strut 212a provide a mechanical advantage to the link 212c so as to reduce the amount of loading imposed on the link 212c. The end 52′a of the threaded member 52′ acts as a fulcrum at the second notch 216a so that a force on the link 212c, and hence the retention of sealing assembly 300 against fluid pressure in the passage 16 is magnified by the lever 212b.
(46) A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, it is intended that the present invention not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.