This invention relates to fire protection sprinklers, and more particularly to fire protection sprinklers for an upright orientation installation.
An automatic fire protection sprinkler is a fire suppression or control device that operates automatically when its heat-activated element is heated to its thermal rating or above allowing water to discharge over a specified area to address a fire. Automatic sprinklers can be configured for a pendent or an upright installation. An “upright sprinkler” is defined by its installation orientation in which the sprinkler is installed in such a way that the water spray is directed upwards against a fluid deflector member for distribution below and about the sprinkler.
An upright sprinkler generally includes a sprinkler frame body having an inlet, an outlet and internal passageway extending in between. Spaced from the outlet is the fluid deflector member, which for some upright sprinklers is generally domed shape or geometry. In an upright sprinkler installation, the inlet is connected to a firefighting fluid supply line of, for example water, for receipt of water at an operating pressure of the sprinkler. In an open or actuated state, the water flows from the inlet and is discharged out the outlet to impact the deflector member for distribution at some distance below the deflector in a spray pattern characterized by a defined area of coverage with a defined distribution density profile. Commercial examples of upright sprinklers include: (i) the Ultra K17-16.8 K-factor Upright Control Mode Specific Application Sprinkler; and (ii) the Model ESFR-17, 16.8 K-factor Upright Sprinkler Early Suppression, Fast Response from Tyco Fire Products; (iii) and the Victaulic K25.2 FireLock™ Standard Response, LP-46 Low Pressure Storage, Upright-Model 4603 from the Victaulic Company. Additional examples of Upright sprinklers are shown and described in U.S. Pat. Nos. 5,862,994; 7,819,201; and 8,122,969 and U.S. Patent Publication No. 2008/0073088. These known commercial upright sprinklers and upright sprinkler technology of the representative patent documents are used in a preferred manner for protection of stored commodities.
The distributed spray pattern of the sprinkler is provided by one or more dimensional parameters of the sprinkler including, for example, the size of the sprinkler outlet or orifice, the geometry of the deflecting surface(s) of the deflector member, the distance between the deflecting surface(s) and the outlet, and other structure features of the sprinkler. For the upright domed deflector, a generally concave deflecting surface is presented to the outlet of the sprinkler which can be characterized by a maximum deflector diameter, a spherical radius and an overall deflector height.
Applicant believes that the spray pattern of a sprinkler can be determined and/or evaluated by examining the spray pattern from the sprinkler in actual or simulated installation conditions. Industry accepted guidelines and standards for the installation of sprinklers, for example, those published by the National Fire Protection Association or FM Global, set installation guidelines and/or requirements for certain occupancies, such as for example, for the protection of storage occupancies and stored commodities of over twenty-five feet. In the case of storage, there are guideline requirements which require a minimum clearance of at least three feet between the deflector member and the top of the commodity. Accordingly, for storage type upright automatic fire protection sprinklers, the characteristics of a spray pattern at least three feet below an upright deflector is of interest to applicants because it is believed it can define how water distributed from the sprinkler wets the stored commodity and addresses a fire therebetween to further define the protection performance and/or limits of the upright sprinkler. It is believed that there are no known commercially available ceiling-only fire protection sprinklers or upright sprinkler technology that provide a spray pattern for storage protection at heights higher than currently commercially available.
Preferred embodiments of an upright fire protection sprinkler provide for a preferred automatic upright fire protection sprinkler assembly. The preferred sprinkler includes a fire protection sprinkler including a frame having a body having an inlet, an outlet, and defining an internal passageway extending between the inlet and the outlet along a sprinkler axis to define a preferred nominal K-factor ranging from 16.8 to 36.4. A sealing assembly is disposed in the outlet with a heat-responsive trigger to maintain the sealing assembly in the outlet. A deflector member is centered, axially aligned with the sprinkler axis, and spaced from the outlet end of the internal passageway. The deflector member has an outer surface and an inner surface that preferably includes: a peripheral region, a central region and an intermediate region between the peripheral and central region. The intermediate region preferably includes a primary deflecting surface, a secondary deflecting surface and a transition from the primary deflecting surface to the secondary deflecting surface. The transition defines a perimeter about the secondary deflecting surface such that the secondary deflecting surface is preferably surrounded by the primary deflecting surface.
Preferred embodiments of the sprinkler assembly and its deflector member define a geometries to produce a desired spray pattern below and about the sprinkler. In another preferred embodiment of an automatic upright fire protection sprinkler includes 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 to define an orifice diameter and a nominal K-Factor ranging from 25.2-36.4 and more preferably at least 33.6. The preferred upright sprinkler includes a deflector member preferably of a domed geometry centered, axially aligned with the sprinkler axis, and spaced from the outlet of the internal passageway.
The preferred deflector member has an outer surface and an inner surface including: a peripheral region defining a peripheral edge that substantially circumscribes the sprinkler axis and a maximum deflector diameter. A central region of the deflector is spaced from the peripheral edge along the sprinkler axis to define a total deflector height; and an intermediate region and between and preferably contiguous with the peripheral region and the central region to define a spherical radius of curvature with a center disposed along the sprinkler axis. The deflector member is preferably characterized by at least one of: a ratio of a orifice diameter-to-spherical radius ranging from 0.65-0.75; a ratio of maximum deflector diameter-to-spherical radius ranging from 1.90-1.95; a ratio of maximum deflector diameter-to-total deflector height ranging from 3.45-3.55; or a ratio of spherical radius-to-total deflector height ranging from 1.80-1.85.
In another preferred aspect, embodiments of the preferred deflector member provide for generation of preferred spray patterns including a preferred substantially non-circular spray pattern in a collection grid of one cubic foot of collection buckets four feet (4 ft.) beneath the peripheral region of the deflector member with water discharged for a duration of about two minutes from the outlet at a minimum pressure ranging between 30 and 50 psi. Each of the collection buckets is centered at one-foot increments relative to a lateral axis and a longitudinal axis, the lateral and longitudinal axes being orthogonal to one another and intersecting one another to define an origin located along the sprinkler axis. The non-circular spray pattern defines at least four zones of fluid density concentrically formed about the sprinkler axis, the four zones including a first zone defining the central region of the spray pattern, a third zone defining a perimeter of the spray pattern with a second zone formed between the first and third zone, and a fourth zone formed about the third zone. The fluid density in the third zone preferably ranges from 40%-60% of the fluid density in the first zone with the first zone having at least three collection buckets each having a fluid density greater than the fluid density in each of the collection buckets of the second, third and fourth zones.
In another preferred aspect of the upright fire protection sprinkler, the sprinkler frame includes a pair of frame arms and an apex. The frame arms are diametrically opposed about the outlet and extending away from the outlet to converge toward the apex that is axially aligned with the sprinkler axis. The apex has a distal end that defines the maximum diameter of the apex. The preferred sprinkler further includes a retention member and a threaded member to fasten the deflector member to the apex. The preferred retention member defines an annular deflector engagement surface for engaging the outer surface of the deflector. The annular deflector engagement surface has an inner diameter and an outer diameter with the inner diameter being greater than the maximum diameter of the apex.
The preferred automatic upright sprinklers include a heat-responsive trigger to maintain a sealing assembly in the outlet. The heat responsive trigger is preferably one of a bulb-type trigger or a strut-lever and link assembly. In embodiments in which the heat-responsive trigger is a bulb-type trigger, a thermally responsive glass bulb having a first end and a second end is disposed on a trigger axis substantially coaxial with the sprinkler axis. The first end of the bulb defines a first seat diameter and the second end defines a second seat diameter. The bulb length between the first seat diameter and the second seat diameter is preferably greater than 1.0 inch, more preferably about 1.5 inches. In one preferred aspect, the first seat diameter is less than the second seat diameter and a ratio of the first seat diameter to the second seat diameter is approximately 0.5 to 0.6:1. In another preferred aspect, the glass bulb has a maximum wall thickness between an outer surface and an inner surface and a length between the first seat diameter and the second seat diameter, a ratio of the maximum wall thickness to the length ranging from 1:30 and 1:40.
Although the Summary of the Invention and the preferred embodiments are directed preferred embodiments of an upright fire protection sprinkler assembly for generating a preferred spray pattern, it should be understood that the preferred embodiments and features thereof can cover other upright sprinkler configuration and/or other nominal K-factors and combinations thereof which provide a spray pattern other than the preferred spray pattern. The Summary of the Invention is provided as a general introduction to some embodiments of the invention, and is not intended to be limiting to any particular sprinkler configuration or assembly. It is to be understood that various features and configurations of features described in the Summary of the Invention can be combined in any suitable way to form any number of embodiments of the invention. Some additional illustrative embodiments including variations and alternative configurations are provided herein.
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.
Like reference symbols in the various drawings indicate like elements.
Referring to
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.
Referring to
As seen in
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
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
In the preferred embodiment of the deflector 100 of
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
As seen in
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.
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.
The deflector 100 is preferably mechanically fastened to the sprinkler frame 12. Referring to
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.
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
Referring to the cross-sectional view of the sprinkler assembly 10 in
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=KVP 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)1/2; (ii) 16.8 (16.0-17.6) GPM/(PSI)1/2; (iii) 19.6 (18.6-20.6) GPM/(PSI)V; (iv) 22.4 (21.3-23.5) GPM/(PSI)1/2; (v) 25.2 (23.9-26.5) GPM/(PSI)1/2; (vi) 28.0 (26.6-29.4) GPM/(PSI)1/2; (vii) 33.6 (31.9-35.28) GPM/(PSI)1/2; and 36.4 (34.6-38.2) GPM/(PSI)V2.
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)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.
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.
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.
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
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.
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%.
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
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 meter1/2sec1/2(m1/2s1/2) to about 160 meter1/2sec1/2 (m1/2s1/2). 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 meter1/2sec1/2 (m/s1/2) to 160 meter1/2sec1/2 (m1/2s1/2), preferably at least 135 meter1/2sec1/2 (m1/2s1/2) to about 160 meter1/2sec1/2 (m1/2s1/2), more preferably 150 meter1/2sec1/2 (m1/2s1/2) to about 160 meter1/2sec1/2 (m1/2s1/2), and even more preferably 160 meter1/2sec1/2 (m1/2s1/2). Further in the alternative, the RTI can range to 50 meter1/2sec1/2 (m1/2s1/2) or less so as to be a “quick” or “fast” response type sprinkler.
Preferred embodiments of the sealing assembly 300 are shown in
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
As shown in
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.
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.
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.
This application is a continuation of U.S. patent application Ser. No. 17/893,516, filed Aug. 23, 2022, which is a continuation of U.S. patent application Ser. No. 16/831,465, filed Mar. 26, 2020, which is a continuation of U.S. patent application Ser. No. 15/574,380, filed Nov. 15, 2017, which is a national stage application of International Application No. PCT/US2016/035579, filed Jun. 2, 2016, which claims the benefit of priority to U.S. Provisional Patent Application No. 62/170,048, filed Jun. 2, 2015, and to U.S. Provisional Patent Application No. 62/170,053, filed Jun. 2, 2015, each of which is incorporated by reference in its entirety.
Number | Date | Country | |
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62170053 | Jun 2015 | US | |
62170048 | Jun 2015 | US |
Number | Date | Country | |
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Parent | 17893516 | Aug 2022 | US |
Child | 18584077 | US | |
Parent | 16831465 | Mar 2020 | US |
Child | 17893516 | US | |
Parent | 15574380 | Nov 2017 | US |
Child | 16831465 | US |