US 2322521 A
Description (OCR text may contain errors)
June 22, 1943. w. E. JENKINS I 2,322,521
THERMOSTATICALLY CONTROLLED GAS VALVE 592/ c1 IZ- F 49 r l i 5 62 4 I l -15 mal.
' /Z 4% lag v T L x J /7 lllllllilll'lllllillH 42- I Patented June 22, 1943 THERMOSTATICALLY CONTROLLED GAS VALVE Wayne E. Jenkins, Los Angeles, Calif., assignor to Domestic Manufacturing Company, Inc., Los Angeles, Calif., a corporation of California Original application August 9, 1940, Serial No. 351,976. Divided and this application August 8, 1941, Serial No. 405,943
3 Claims. (01. 251- 37) The invention relates to thermostatically controlled gas valves and more particularly to a pilot operated thermostatically 7 controlled shut-off valve. The present application is a division of my application Serial No. 351,976, filed August 9. 1940, for Thermostatically controlled shut-off device.
In the type of mechanism to which the present invention relates and as disclosed in my aforesaid parent application, a thermal-responsive thermostatic element is associated with a pilot burner of a heating system and which operates as a holding and trip mechanism for a gas valve controlling the flow of fuel to the main burner of the heating system, whereby the valve is normally held by the thermostatic trip mechanism in open position while the pilot burner is ignited and functioning in its proper manner, but is released by the trip mechanism for closing of the valve upon extinguishing of the pilot flame to thereby prevent the flow of gas to the main burner while the pilot burner is extinguished. In such a mechanism and as will be understood, the valve is held in a fixed open position for a substantially indefinite period of time and operates only in the event that the pilot burner is extinguished. The valve mechanism is customarily spring loaded so as to move to closed position when released by the thermostatic mechanism and this closing movement of the valve is very fast and abrupt. Difiiculty has been heretofore encountered in providing a valve structure in devices of the character described which will positively seal the gas line with which the valve is used and which can otherwise be thoroughly relied upon to properly operate after long periods of inactivity. In accordance with the foregoing and as one of the principal objects of the present invention, I provide a valve structure of the character described which when released by the thermostatic mechanism will automatically and rapidly move to a fully closed gas sealing position and which is so designed and constructed as to be self-adjusting in its seating operation so as to accommodate itself to and overcomefiminor defects in alignment and forming of the valve parts.
Another object of the invention is to provide a valve structure of the character described which is formed of a few sturdily made parts designed to provide satisfactory long life and operation and which is designed and arranged in a compact manner wherein the several valve parts and location thereof are readily accessible for assembly and subsequent inspection, repair or replacement where necessary.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth inthe claims;
Referring to said drawing:
Figure l is a side elevation of a thermostatically controlled gas shut-ofi valve constructed in accordance with the present invention.
Figure 2 is a longitudinal sectional view of the device shown on an enlarged scale with refer; ence to Figure 1, and showing the valve in open position.
Figure 3 is a cross sectional view of the device taken substantially on the plane of line 33 of Figure 1.
Figure 4 is a fragmentary sectional view of the valve mechanism similar to Figure 2 but showing the valve in closed position.
The device of the present invention is as aforementioned a pilot operated gas shut-off valve and the several parts of the device are unitarily associated with and supported by a main body 6 herein the form of a casting and provided with an internal valve chamber i divided by a partition wall 5 into inlet and discharge compartments 8 and 9, the partition wall bein formed with a gas passage in therethrough bounded an an annular valve seat ii. The body is formed with gas inlet and discharge passages 02 and it connected to the compartments 8 and 9 and which are formed in opposite sides of the body in substantially axially aligned relation. The wall of the body defining the passage i2 is here threaded exteriorly for the receipt of a coupling nut i l of a fitting for an inlet conduit i5, and the wall of the body defining the discharge passage i3 is here threaded interiorly for receipt of an end of a discharge conduit 20. The aligned arrangement of passages 52 and it as above mentioned, disposes the inlet and discharge conduits at the opposite sides of the body 6 and n substantial alignment and in this connection it is to be iurther noted that the partition wall 5 and the gas passage i0 therein is arranged in a plane substantially parallel to the longitudinal axes of passages i2 and i3 whereby the axis of passage H] is at right angles thereto. Aligned with the axis of the passage I0, is an open portion l6 formed in the body and communicating with compartment 8 and threaded into this opening is a closure plug I1 which is formed with a central aperture l8 aligned with the gas pas: sage l and the valve seat II. The opposite side wall IQ of the body is here formed with a boss 2| within which is formed a threaded opening 22 which is also in alignment with the valve seat II and the closure aperture l8. Threaded into the opening 22 is an end of a tube 23 which pro- Jects outwardly from the body wall M in substantial alignment with the parts aforementionel. A valve guiding and actuating member is positioned axially of the aforementioned parts and includes a rod 25 slidably mounted within the tube 23 and extending into the valve chamber centrally through the seat H where the same is telescoped into an extension part 26 which in turn continues through the closure aperture W to the exterior of the body. Preferably the rod sections 24 and 26 are held together by means of a pressed fit.
As will be seen from the drawing, the valve seat ii faces into the inlet chamber a, and mounted in this chamber upon the rod section 26, is a valve backing plate 21 having a central aperture 28 loosely encompassingthe rod section 26 so as to afford the backing member complete freedom of movement along the rod and substantial freedom to move transversely of the rod and to rock upon the rod. A valve disc as, preferably of a soft compressible material such as rubber or various compounds thereof or substitutes therefor as neoprene, is mounted between the backing plate 21 and the valve seat It and in the closed position of the valve is held against the seat by means of the backing member 21. The disc 29 is here formed with a central aperture 3B which snugly but slidably fits the rod section 26 for maintaining a seal about the rod in a closed position of the valve.
Spring means is connected to the valve hacking member 21 for normally urging the valve to closed position and as here shown, this means is embodied in the form of a helical spring 32 which is compressed between the opposite side of the backing member 21, relative to the side in engagement with the valve disc. and a spring rest 33 slidably mounted on the rod section 26 and. supported longitudinally upon the rod by the closure i1. Preferably, a sealing gasket 32 having a center aperture snugly fitting the rod section 26 is mounted between the spring rest 33 and the inner side of the closure 11 for sealing ofi the closure aperture 18, and as will be understood, the spring rest 33 is normally held in against the gasket 34 maintaining the latter under compression by reason of the constant compressive force of spring 32. In the closed position of the valve, as illustrated in Figure 4, the valve disc 29 is firmly compressed against the seat H by reason of the spring force operating on the backing plate 21. A serious problem has been heretofore encountered in insuring the proper seating of the valve due to minor misalignment or angularity of shape of the several parts and also due to irregularities in the thickness of the valve disc 29. I have found that the loose support of the backing plate 28 on the rod section 26, provided by the clearance at the aperture 28, is of considerable importance in overcoming the prior difficulty and in insuring positiveness in the sealing of the valve. By reason of this construction, the backing plate 21 is permitted sufllcient universality in its movement to enable the same to be self-adjusting to any minor misalignment or angularity of the several parts. Also this universality of mounting of the backing member upon the rod positively prevents the backing member from wedging or sticking in a misaligned position across the valve seat when suddenly and abruptly moved to closed position after having been held in a fixed open position for a long period of time. Thus when released from its open position by the thermostatic control mechanism, the backing member will move rapidly under the relatively powerful force of spring 32 to clamp the valve disc 29 against the seat 5 i and in its closed position, the backing member may rock slightly upon the rod under the urge of the spring force until a maximum support of the valve disc against the seat is obtained.
I have also found that the uniformity and positiveness of the seal obtained may be additionally insured by constructing the side 36 of the backing member, facing the valve disc, with a small concavity 35 so that any irregularity in the thickness of the valve disc may be compensated for by a partial seating or nesting of the disc within the hollow concavity. In this connection I prefer to form the diameter of the disc somewhat greater than the diameter of the backing plate 21 so that the disc will overlie the periphery of the backing member, and the diameter of the seat H is formed somewhat smaller than the diameter of the backing plate so as to obtain a contact of the disc within the dimensions of the concavity provided in the side 36 of the backing member. This relationship of the parts is best illustrated in Figure 4, wherein the valve is illustrated in closed position. With, reference to this view it will be seen that the valve seat I l is preferably formed as an annular knife edge and similarly, the contact of the backing member 21 with the disc is provided by an annular knife edge 40 defined at the periphery of the backing member by reason of the concavity 35 formed in the face 36 of the member. By reason of this arrangement, it will be seen that the valve disc 29 is engaged on its opposite side by the concentrically arranged knife edges with the ring of contact of valve seat I l arranged concentrically within the ring of contact of the backing member 21. Thus the compressible valve disc 29 is very firmly gripped between the valve seat and the backing member and may be de: formed slightly into the concavity in the face of the backing member so as to completely compensate for any minor variations in thickness of the disc as are likely to occur in commercial production.
The valve is arranged to be opened manually and for this purpose I' provide on the outer end of the rod section 26 a hand engaging knob 38, here secured to the end of the rod section 26 by means of a screw 39. An actuating connection between the rod and the valve is here obtained by means of a collar 4| which may be pressed or otherwise secured to the rod above the valve disc 29, so that upon longitudinal displacement of therod, that is downwardly with respect to Figures 1 and 2, by drawing outwardly of the knob 98, the collar 4| will be moved against the face of the disc so as to draw the disc and backing plate away from the seat against the resilient action of spring 32. Preferably, inasmuch as the manual setting of the valve will ordinarily be efiected only occasionally, I prefer to enclose the knob and the outer rod portion within a casing 42 which in the present instance is threaded onto an outwardly extending flange portion 43 of the closure 11, If desired and as here shown, a seal- 2,322,521 ing gasket 44 may be mounted between the inner end of the casing 42 and the outer side of the closure so that when the casing is threaded home against the gasket. an effective sealing oi! of the interior gas passage is accomplished.
The valve mechanism is designed to be held in open position, as illustrated in Figure 2, by means of a thermal-responsive element 45 which is arranged to operate as a catch for the rod in a heated position of the element and to release the rod in a cool position of the element to permit closing of the valve by means of the spring 32. The element 45, as will be presently described, is thermally associated with a pilot burner and normally maintained in a heated comdition by the pilot burner so as to hold the valve mechanism in open position but will automatically release the valve for closing upon extinction of the pilot burner. The element 45 is supported adjacent the outer end of tube 23 by a. bearing sleeve member 41 which serves as a bearing for the outer end portion 48 of the rod and is in the present instance locked in place by means of a nut 49 abutting the end of the tube.
The thermostatic element here used is of the bi-metallic type and is composed of a strip having a substantially straight center portion 50 and an offset end 53 which is apertured to surround the bearing sleeve member and is clamped in place between an annular shoulder 5l' on the sleeve member'and a spacer member 52 mounted below the shoulder and upon the nut 49. The center portion 50 of the strip is thus positioned substantially parallel to and alongside of the outer end portion 48 of the rod, which as will be seen in Figure 2 projects from the outer end of the sleeve member 41, and the outer end 54 of the strip is offset in the direction of the rod so as to hook over the end face 56 of the rod in a heated position of the strip and when the rod has been displaced longitudinally to an open position of the valve. The construction of the bi metal strip is such that the same will flex the outer end 54 thereof towards the rod when the strip is heated and will flex the end 54 away from the rod when the strip is cool so as to release the rod for movement of the valve to closed position.
The bi-metal strip and rod are protected from direct impingement of the pilot flame by the enclosing of these members in a chamber at the outer end of the tube, such as here provided by a casing 51, preferably of a relatively thin metal which is threaded onto the spacer member 52. The casing 51 also serves to seal off the outer end of the tube and bearing sleeve to prevent gas leakage.
The pilot burner is unitarily associated with the other parts on the apparatus so as to properly position the parts in operative arrangement. As here shown, a conduit or tube 58 is threaded into a gas passage 59 provided in the boss 2| and extends outwardly from the boss in substantially parallel relation to the tube 23. A gas Venturi construction is preferably provided in the tube intermediate its ends and above which is provided primary air openings B2. The outer end of the tube is here closed by a plug 53 and a series of burner ports 64 provided adjacent the outer end of the tube and which are spaced and constructed so as to direct flame against the base of casing 51 and also laterally of the casing for ignition of a main gas burner, not shown. A gas conduit 66 for conveying gas to the pilot burner is preferably provided independent of the gas 'Cil passages 8 and l and as will be thus seen from Figure 3, this conduit may be connected to a gas inlet passage 51 communicating with the passage 58 by means of a fitting GI.
In a typical installation of the present device, the gas conduits l3 and I4 are part of the gas main leading to a main gas burner such may be used in a hot water heater, stove, furnace, etc., below the main gas cook control or thermostat or the like. In such installation, it is de sirable to maintain a steady pilot flame and to frequently interrupt the main burner operation. For this reason the pilot burner is connected by a separate conduit 55 to the gas line aheadof the main burner cock or thermostat or the like.
Initially the pilot burner is ignited so as to heat the bi-metal strip and thereafter the casing 42 is removed and the valve manually opened by retraction of the knob 38 so as to cause a booking of the thermostat element over the outer end of the rod. Gas flowing through the open valve to the main burner will then be ignited by the pilot burner. The casing 42 is then preferably replaced so as to protect the exposed parts against accidental or wrongful manipulation. Thereafter at any subsequent time that the pilot flame should be extinguished, as for example by reason of a temporary interruption of the gas supply service or by a blowing out of the pilot flame or the like, the thermostatic strip will be quickly cooled and the main burner valve sprung to closed position to thereafter shut oil the escape of gas and prevent a relighting of the main burner until after the pilot flame has been reestablished. To reset the apparatus it is only necessary to re-ignite' the pilot flame and pull out the knob 38 so as to reengage the thermostatic strip with the rod end.
The arrangement and construction of the thermostatic unit for controlling the operation of the valve and the other general assembly of parts including the pilot burner, is more fully described in my aforesaid copending application, Serial No. 351,976, and is being claimed in that application.
1. In a thermostatically controlled trip operated gas shut-off valve of the character described, a body formed with a valve chamber and having an annular valve seat in said chamber defined by a circular sharp edged shoulder, a valve guide mounted in said chamber axially of said seat, a. valve backing member having a central aperture loosely surrounding said guide to permit longitudinal and substantial rocking movement thereon and formed on the side thereof facing said seat with an annular shoulder concentric to said guide and of a greater diameter than said seat shoulder, a valve disc of compressible material having a central aperture snugly fitting said guide and mounted between said seat and backing member shoulders and being of a larger diameter than said backing member shoulder whereby the opposite sides of said disc will be clamped between said shoulders in the closed position of said valve with said seat shoulder engaging said disc concentrically of and within the confines of said backing member shoulder, and spring means engaging said backing member and urging the latter and said disc towards said seat shoulder.
2. In a thermostatically controlled trip operated gas shut-off valve of the character described,
a body formed with a valve chamber and having an annular valve seat in said chamber, an actuating rod mounted for reciprocation in said body and extending axially through said seat, a valve backing member having a central aperture loosely surrounding said rod to permit longitudinal and substantial rocking movement thereon,
- a valve disc of compressible material having a central aperture snugly fitting said rod and mounted betweensaid backing member and said seat and having a diameter substantially larger than said backing member, spring means engaging said backing member and urging the latter and said disc to said seat, and a collar fixedly mounted on said rod at the opposite side of said disc relative to said backing member and engageable with said disc centrally thereof for moving said disc and backing member away from said seat against the resilient action of said spring means upon corresponding movement of said rod, the side of said backing member facing said disc being hollowed out centrally thereof to permit a nesting of a portion of said disc therein.
3. In a thermostatically controlled trip operated gas shut-off valve of the character described, a body having a valve chamber and formed with an annular valve seat within said chamber and an opening through a side of said body aligned with said seat, a closure for said opening having a central opening therein aligned with said seat, a rod reciprocally mounted in said body axially through said seat and closure opening, a valve backing plate mounted in said chamber adjacent said seat and having a central aperture loosely surrounding said rod to permit longitudinal and substantial rocking movement thereon, a valve disc of compressible material having a central aperture snugly fitting said rod and mounted between said backing member and said seat, a spring rest mounted on said rod between said backing member and closure, a helical spring surrounding said rod and compressed between said backing member and spring rest to urge said backing member and disc towards said seat, a sealing gasket carried by said rod and mounted between said rest and closure for sealing oil said closure opening. a collar fixed to said rod at the opposite side of said disc relative to said backing member and movable with said rod against said disc for displacing the latter away from said seat against the resilient action of said spring, the outer end of said rod extending from said closure being manually engageable for movement of said rod to an open position of said valve as aforesaid, and a cap de'tachably carried by said closure at the exterior side thereof for enclosing the outer end of said rod.
WAYNE E. JENKINS.