US2693200A

US2693200A - Thermostatic gas cock

Info

Publication number: US2693200A
Application number: US184151A
Authority: US
Inventors: John H Grayson
Original assignee: General Controls Co
Current assignee: General Controls Co
Priority date: 1950-09-11
Filing date: 1950-09-11
Publication date: 1954-11-02
Anticipated expiration: 1971-11-02

Description

Nov. 2, 1954 J. H. GRAYsoN wo 0% cl l G1 E Tt AD. Te SS .Wd Re El Hi TF United States Patent O THERMOSTATIC GAS COCK John H. Grayson, Monrovia, Calif., assignor, by mesne assignments, to General Controls Co., Burbank, Calif., a corporation of California This invention relates to thermostatic gas cocks, and is more particularly concerned with improvements upon that disclosed in my copending application, Serial No. 629,592, tiled November 19, 1945, which resulted in Patent No. 2,524,788, issued October 10, 1950.

All thermostatically controlled gas appliances, such as storage type water heaters, require a main gas cock for manually turning the gas on and off independently of the functioning of the thermostatic valve, and it was the practice, prior to the design of my copending application, to provide the thermostatic valve in one body and the gas cock in another separate and distinct from the thermostatic valve. plication the shut-olf and thermostatic control facilities are combined in a single thermostatc valve with a view to simplicity, economy, compactness and improved performance, and it is the principal object of my present invention to further improve the design and construction of that Valve with a view to even greater simplicity and economy in construction as well as greater compactness and still more improved performance.

, 2,693,200 Patented Nov. 2, 1954 enticzm, this section being taken on the line 1--1 of Fig. 2 is an end view of Fig. l;

Fig. 3 is a side view of Fig. 2, and

Figs. 4 and 5 are cross-sections of the body casting taken on the correspondingly numbered lines of Fig. l.

'Ille same reference numerals are applied to corresponding parts throughout these views.

Referring to Fig. l, the thermostat in connection with which my invention is illustrated comprises the

usual elements

7 and 8, the one being non-expanding or having a low coeicient of expansion, and the other being expansible or having a comparatively high coeflicient of expansion, as, for example, the movable element 7 may be a rod of invar and the fixed element 8 may be a brass or copper tube. 'Il-le tube 8 is threaded, as at 9, in the hole in the center of the wall 10 provided in the inner end of the hollow neck 11 forming a part of the cast hollow valve body or casing 12. The neck 11 is threaded into an adapter 13 which is welded or otherwise suitably fixed in a hole in the wall 14 of the tank of a gas-operated water heater, for example, insulation being indicated at In the valve of my copending ap- 15 surrounding said tank and enclosed by an outer wall 16 of sheet metal. The rod 7 is adjustably secured at its outer end in the outer end of the tube 8, as by threading into a plug 17 which in turn is fixed in the end of the tube 8. By virtue of this connection, it is evident that expansion and contraction of the tube 8 results in slight endwise movement of the rod 7. It will also be evident that a temperature adjustment is obtainable by turning the rod 7 with respect to the tube 8, thus threading the rod in or out with respect to the plug 17. A lever 18 is at- The present valve contains the following improvements n over the prior art and my earlier valve:

, (l) The snap-action valve, instead of being arranged to seat on the large end of the tapered, manually operated, shut-off plug, is disposed in a counter-bore provided in the large end of the plug which forms a valve chamber wherein a valve seat is provided, thereby enabling a shortening in overall length of the valve and reducing the extent of its protrusion from a heater;

(2) The inset valve design leaves enough wall thickness on the large end of the plug annularly of the valve chamber to enable annularly grooving that portion of the plug to receive a coiled compression spring which can be held caged by a circular retaining plate fastened to the valve body, thereby simplifying the matter of keeping the valve seated under a light spring pressure, uslng a simpler and cheaper and also more reliable type of spring, without any complications in the design, the front-location of this spring, where it is easily accessible, if necessary, being also of real advantage;

(3) The manually operable on" and oif lever is attached to the protruding large end of the plug, instead of being attached intermediate the ends of the plug and *worked through a slot in the wall of the body that involves some weakening of the casting and is also objectionable in appearance and for various other reasons, the lever of the present design being, by reason of its front location, more easily operable, besides being neatly covered by the retaining plate, excepting only that portion which must protrude through the arcuate slot in the plate for manipulation, and

(4) The closure cap, instead of being on the body, is threaded into the counterbore in the large end of the tapered plug, projecting more or less through a center hole in the retaining plate for maximum compactness and neatness of design, while still making this part readily accessible for easy removal, that being frequently necessary in valves of this kind, because foreign matter is apt to enter between the snap valve and seat of any time in the operation of the valve and even at the time of installation of a new heater, when the foreign matter is apt to come from the pipes.

The invention is illustrated in the accompanying drawing, in which Fig. l 1s an enlarged longitudinal section through a portion of body 12.

thermostatic gas cock made in accordance with my intached to the projecting end of the rod 7 for the temperature adjustment and operates in the opening 19 in the body 12 between the neck 11 and the main portion of the body moving a pointer 20 relative to suitable graduations on the outside of the body 12. The rod 7, in its endwise movement, transmits movement to a cylindrical plunger 21 that is slidably guided in the bore 22 of a plug 23 threaded in the cylindrical extension 24 of an accurately machined tapered bore 25 provided in the main A gasket ring 26 is compressed by the rim 27 of plug 23 to seal the body 12 against gas leakage. A dished convexo-concave snap-action disk 28, made of thin spring material, such as spring bronze, rests loosely at its outer periphery in the inner end of bore 22 and is normally convexed toward plunger 21 which has an annular knife-edged shoulder 29 projecting from its inner face and disposed in line contact in a circle on the adjacent side of the disk. However, when the tube 8 cools and contracts, moving the rod 7 to the left, pressure is exerted on the disk 28 by the plunger 21 tending to flatten it until a dead-center or ilat condition is reached, whereupon the slightest additional pressure causes the disk to snap past dead-center and in so doing to open the valve 30 by operation of the push rod 31. A coiled compression spring 32 normally holds the valve 30 closed but yields under pressure of the disk 28 in its snap-action to permit opening of the valve. A bowed leaf spring 33 is caged between the body 12 and the attached end of lever 18 on the end portion of the rod 7 and gives with the movement of the rod inthe operation of the thermostat and by its friction drag on the body helps to insure keeping the'thermostat rod in whatever statey of adjustment it is set by means of the lever 18.

The body 12 has a neck 34 cast integral therewith into which the gas supply pipe 35 is threaded for delivery of gas through a radial port 36 communicating with the tapered bore 25 intermediate the ends thereof. Another neck 37 is cast integral with body 12 into which a gas outlet pipe 38 is threaded for discharge of gas to the main burner of the water heater when the valve 30 is open, there being a radial port 39 communicating with cylindrical extension 24 of the bore 25 and opening into the neck 37 for discharge of gas thereto. Still another but much smaller neck 40 is cast integral with body 12 into which a tube leading to the pilot burner for the main burner is adapted to be threaded, this neck having communication with the bore 2S through a radial port 41 connected to one end of an intermediate transverse passage 42 and another passage 43 connected to the other end of said intermediate passage, ow of gas through these connecting passages being regulated in the usual way by means of an adjustable screw threaded plug 44 controlling ow from port 41 into passage 42. The port 41 is suitably arranged so as to be left open only so long as the tapered, manually operable, shut-off plug 45 is in the on position.

In accordance with my present invention, the tapered plug 45 has a counter-bore 46 provided coaxially of the large end thereof which serves as a valve chamber to accommodate the snap-action valve 3u. A radial port 47 in the plug is arranged to register with port 36 in the body 12 when the plug is in the on position, complete shutoff of gas to the main burner and its pilot burner being provided when said plug is turned to the off position. A knife-edged, circular valve seat is provided in the inner end of said counterbore 46, as shown at 48, circumscribing a circular series of ports 49 in the plug and an axial valve stem guide 50 in which the push rod 31 previously mentioned is reciprocable. The rod 31 slides freely in the guide t) and in a coaxial guide 51 provided in the plug 23. Another counterbore 52 is provided coaxially of the small end of the plug 45 so as to reduce resistance to gas ow through the valve when the valve 3i) is open. B v housing the valve 3) in a counterbore in the large end of the plug, instead of having it arranged to seat on the large end, an appreciable reduction in overall length for a given size valve is made possible and accordingly the extent to which the valve need project from the heater is also reduced, a reduction in overall length of about 5s being realized because of the elimination of the chamber otherwise required beyond the large end of the plug to house the valve and its closing spring.

The present design, however, also affords these further advantages:

(1) An annular groove 53 can be provided in the large end of the plug in the thick wall surrounding the counterbore 46 to house a coiled compression spring 54 for holding the plug 45 seated under spring pressure, in addition of course, to the gas pressure that is effective against the counterbored end portion 46 of the plug tending to hold the valve 30 seated and the plug also, the coiled compression spring 54 being preferred to other types from the standpoint of cost and reliability, other valve designs having made the use of this larger kind of spring impractical because of the space it requires.

(2) The spring 54 is held caged under compression in the groove by the ring-shaped end portion 55 of a manually operable lever 56, this ring portion lying between the end of the plug 45 and a retaining plate 57 stamped, v

like lever 56, from sheet metal to provide an annular attaching ange portion 58 in depressed relation to the embossed circular portion 59 that encloses the ring 55 and the projecting end portion of the plug 45. The flange 58 is fastened by screws 60 to the body 12. In that way, the entire plug assembly is removable easily from the front end of the valve, although the plug 45 seldom requires servicing or regreasing on an automatic water heater. Removal of the plate 57 will also permit removal and inspection and replacement of the spring 54 without disturbing the plug 45, if faulty operation of the valve should indicate a faulty spring. In the valve of my copending application, the spring for seating the plug was applied to the small end of the plug and was, therefore, not accessible without removal of the entire valve from the heater and thereafter disassembling the valve, and, while spring failure with a coiled compression spring is not common, it is not too uncommon with other types.

(3) The lever 56 is connected with the large end of the plug 45 to turn it through about 90 from on to olf position, and vice versa, by means of lugs 61 struck from the ring portion 55 and arranged to register with and engage in notches 62 provided in the end portion of the plug 45. The lever 56 is largely covered up and concealed by the plate 57, there being only the handle portion 63 thereof projecting through an arcuate slot 64 provided in the peripheral wall of the embossed portion 59 of the plate 57 for manual operation. With this arrangement the lever 56 is not only more easily accessible for operation, being on the front end of the valve, instead of intermediate the ends, as in the valve of my copending application, but the valve body casting is made simpler, stronger and cheaper, as well as better looking, because there is no need for an unsightly and weakening slot in the wall of the valve intermediate the ends of the plug receiving bore. Such a slot also offered an opportunity for grease to ooze out and be wasted and it also invited entry of dirt and grit.

(4) The cylindrical closure cap 64, instead of being applied to the valve body, as in the valve of my copending application, is threaded into the counterbore 46, with the tlanged outer end lying inside the circle dened by the spring receiving groove 53, and projecting only slightly through the center hole 65 provided in the embossed portion 59 of the retaining plate 57. A gasket ring 66 is compressed between the cap 64 and the large end of the plug to prevent gas leakage. A screw driver slot 67 is provided in the outer end of the cap for its threading in and out, and a recess 68 is provided on the inside to accommodate one end portion of the coiled compression spring 32 which has its other end engaged over a central boss 69 provided on the back of the valve 30. There is more frequently a necessity for removal of cap 64 because foreign matter may lodge between the valve 30 and the seat at any time in the operation of the valve, and, at the time of installation of a heater, dirt is apt to enter from the pipes and need i cleaning out.

In operation, it is evident from the above description that good performance is insured because the valve 30 and push rod 31 always remain in the same operative relationship to the thermostat 7 8, and the snap action disk 28 operated thereby, regardless of rotation of the plug from one position to another, the valve and its push rod being coaxially` arranged with respect to the plug 45, as well as with respect to the plug 23, in which the disk 28 and its actuating plunger 21 are coaxially mounted. Closest accuracy in this coaxial relationship is possible mainly because of the novel construction of the tapered plug which combines in and on itself, in oneunitary assembly, the snap-action valve 30 together with its operating push rod 31, valve seat 48, closing spring 32, and closure cap 64, as well as the plug seating spring i 54, all turning together as a unit with the lever 56 when the plug 45 is turned one way or the other by means of said lever.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. In a valve mechanism of the character described, a casing having an open end bore provided therein which includes a tapered seat tapering inwardly from the open end, said casing also having ports and associated passages provided therein, the ports communicating with the bore, a tapered tubular shut-off plug closing the open end of said bore and having a close working t in said tapered seat and having a valve chamber formed in the large end thereof arranged to communicate through a port provided in one side thereof spaced inwardly from the large end of the plug with one of the ports in the casing, said plug also being provided with an accurately formed flat valve seat in the inner end of said valve chamber normal to and in coaxial relationship with the axis of rotation of the plug, a valve push rod guided axially relative to and extending from said plug and adapted to be moved endwise from outside said plug, a valve disk in the valve chamber carried on the adjacent end of said push rod and arranged to have a close t on the flat valve seat in said valve chamber, a light closing spring in said valve chamber urging said valve disk toward said sheet, a closure for said valve chamber fixed on and turning with the large end of said plug providing an abutment for the valve closing spring, means retaining said plug in said bore, and manually operable means connected to the large end of said plug to turn the same from one position to another.

2. A valve mechanism as set forth in claim l, wherein the light closing spring for said valve disk is a coiled compression spring which is small in diameter in relation to the large end of said plug and disposed in said valve chamber with its one end abutting the valve disk to urge it toward said seat, and said closure for the valve chamber is also small in diameter in relation to the large end of said plug and fixed to and turnable with said end and provides an abutment for the other end of said valve closing spring, said plug having a circular groove provided in the large end thereof annularly of the closure, the said plug retaining means comprising a light coiled compression spring seated in said groove adapted to hold the plug seated, and a retainer plate encircling said closure and fixed to said casing over the large end of said plug and providing an abutment for said plug seating s ring.

p 3. A valve mechanism as set forth in claim 1, wherein the light closing spring for said valve disk is a coiled compression spring which is small in diameter in relation to the large end of said plug and disposed in said valve chamber with its one end abutting the valve disk to urge it toward said seat, and said closure for the valve chamber is also small in diameter in relation to the large end of said plug and fixed to and turnable with said end and provides an abutment for the other end of said valve closing spring, said plug having a circular groove provided in the large end thereof annularly of the closure, the plug retaining means including a light coiled compression spring seated in said groove adapted to hold the plug seated, the said manually operable means for turning said plug comprising a manually operable lever having a portion attachable to the large end of said plug to turn it and also providing an abutment for said plug seating spring, and said plug retaining means further including a retainer plate encircling said closure and fixed to said casing over the large end of said plug in abutting relation to said lever holding it in attached relation to the plug and backing it up to assume the pressure of said plug seating spring.

4. A valve mechanism as set rortn in claim 1, wherein said plug retaining means comprises a light spring pressing against the large end of said plug to hold it seated, and a retainer plate xed to said casing over the large end of said plug and providing an abutment for said plug seating spring.

5. A valve mechanism as set forth in claim l, wherein said plug retaining means includes a light spring pressing against the large end of said plug to hold it seated, the said manually operable means for turning said plug comprising a manually operable lever having a portion attachable to the large end of said plug to turn it and also providing an abutment for said plug seating spring, and said plug retaining means further including a retainer plate xed to said casing abutting said lever holding it in attached relation to the plug and backing it up to assume the pressure of ,said plug seating spring.

6. A valve mechanism as set forth in claim 1, wherein said plug retaining means includes a light spring pressing against the large end of said plug to hold it seated, and the said means for turning said plug comprises a manually operable lever having a portion attachable to the large end of said plug to turn it and also providing an abutment for said plug seating spring, the said plug retaining means further including a vretainer plate fixed to said casing and having an embossed circular portion overlying the large end of said tapered plug and abutting said lever holding it in attached relation to the plug and backing it up to assume the pressure of said plug seating spring, said embossed portion having an arcuate slot in the peripheral wall thereof through which a radially projecting handle portion of said lever extends for manipulation.

7. A valve mechanism as set forth in claim 1, wherein ing a circular groove provided in the large end thereof annularly relative to the closure, the plug retaining means including a light coiled compression spring seated in said groove adapted to hold the plug seated, the means for turning the plug comprising a manually operable lever having a portion attachable to the large end of said plug to turn it and also providing an abutment for said plug seating spring, and said plug retaining means further including a retainer plate iixed to said casing and having an embossed circular portion overlying the large end of said tapered plug and abutting said lever holding it in attached relation to the plug and backing it up to assume the pressure of said plug seating spring, said embossed portion having an arcuate slot in the peripheral wall thereof through which a radially projecting handle portion of said lever extends for manipulation.

8. in a valve structure comprising a ported body, a snap-action dished spring disk, a push rod movable endwise in said body, and a valve operated by said push rod against resistance of a closing spring, the improvement which consists in the provision of a tapered open end bore in said body tapering inwardly from the open end, a manually oscillatable, hollow, tapered plug tting closely in said tapered bore and having a radial port registei'able with a port in said body in one position of rotary adjustment of said plug, said plug having a valve chamber therein in the larger outer end accommodating said valve and a seat in said chamber which said valve engages to shut off iiow, said plug extending to the outside of said body and having a closure on its outer end removal of which affords access to the valve chamber and valve therein, said closure providing an abutment for said closing spring, spring means active against the larger outer end of said plug to hold it seated in said tapered bore, a manually operable lever attachable to the large outer end of said plug and holding said spring means in operative relation to said plug, and a retaining plate secured to said body over the large outer end of said plug serving as an abutment for said lever to hold it in operative relation to said plug and spring means.

References Cited in the iile of this patent UNITED STATES PATENTS Number Name Date 1,919,265 Vaughn July 25, 1933 2,011,690 Schonfeld Aug. 20, 1935 2,037,684 Hegwein Apr. 14, 1936 2,228,701 Hanson Jan. 14, 1941 2,229,826 Thornberry Ian. 28, 1941 2,322,518 Huber June 22, 1943 2,524,788 Grayson Oct. 10, 1950 2,553,575 Grayson May 25, 1951