US2814447A

US2814447A - Valve structure

Info

Publication number: US2814447A
Application number: US509856A
Authority: US
Inventors: George P Greenamyer
Original assignee: General Controls Co
Current assignee: General Controls Co
Priority date: 1955-05-20
Filing date: 1955-05-20
Publication date: 1957-11-26
Anticipated expiration: 1974-11-26

Description

Nov. 26, 1957 G. P. 'GREENAMYER 2,814,447

VVALVE TRUCTURE Filed uay 2o, 1955 /5` /6 Y 3 2 5 23 l /7 4 l 30' 5 27 32 f/ H/@H F/,QE

` 4f /9 s /s A ZZ 2d 52 3 27' 32 33,' 7

5.5 ya 25 `55 j, 37 25 1f "25 1W t 3 '2g 0W F/@E OFF .36 /9' Zhwentor, 4 2 650265,? @25mm/W52 39 3M. g B

l' ff. guai l (ttorneg United States Patent VALVE STRUCTURE George P. Greenamyer, Monrovia, Calif., assignor to General Controls Co., Glendale,r Calif., a corporation of California Application May 20, 1955', Serial No. 509,856

The portion of the term of the patent subsequent to April 10, 1973 has been disclaimed or dedicated to the public 13 Claims. (Cl. 236-48) This invention relates to valve structures of the type more particularly adapted for controlling supply of fuel gas to heating equipment and which includes thermostatically operated valve means for maintaining an even temperature in a space, such as a room or oven, heated by the equipment.

The invention of the present application has substantially the same objects in View as those of the inventions disclosed in the copending applications of Richard D. Grayson, Serial No. 476,633, led December 21, 1954, now Patent No. 2,766,773, granted October 16, 1956, and Serial No. 483,683, filed January 24, 1955, now Patent No. 2,741,266, granted April 10, 1956, and constitutes, in some respects, an improvement thereon.

A general object of this invention is to provide a valve structure which includes a pair of valves arranged in series to control ilow of gas from the inlet to the outlet of the structure and means, including means movable gradually in response to variation of the space temperature, for operating the valves sequentially and so as to control flow of gas to the equipment burner in the following manner:

When the space temperature is considerably below that for which the temperature responsive means is set the valves are fully open so that gas then passes through thestructure at a rate such that a high-tire condition of the burner is produced. With rise of space temperature the valve adjacent the outlet of the structure is closed gradually to modulate the flow, and when it is fully closed gas passes by way of the still-open inlet valve through a restricted passage, luy-passing the outlet valve, to produce a predetermined low-fire condition of the burner. With continued rise of spacer temperature, if such should occur despite the low-fire, the inlet valve is closed so that supply` of gas to the burner is shut 01T. With subsequent fall oi space temperature, due to the absence of heating, the outlet valve is opened, at least partially, before the inlet valve is opened, so that when the inlet valve is subsequently opened gas can pass at relatively high rate (Sullicient to ensure lighting of the burner by the usual means) by way of the outlet valve as well as through the restricted passage.

For full understanding of the invention, and further appreciation of its objects and advantages, reference is to be had to the following detailed description and accompanying drawing, and to the appended claims.

In the drawing:

Figure l is a more-or-less diagrammatic sectional View of a valve structure embodying this invention; and

Figures 2, 3 and 4 are views of a part of the structure of Fig. l showing the valves in dilterent positions assumed in operation.

Referring first more particularly to Fig. l, the numerals 11 and 12' indicate the two interconnected sections of a valve casing having an inlet 13, an outlet 14, and an elongated generally-cylindrical cavity therebetween which is divided by a pair of transverse partitions 15 and YICC 2 16 to form an inlet compartment 17, an outlet compartment 18, and a chamber 19 between the partitions. In the bottom wall of chamber 19 is a right-angled passage 20 which leads, through both sections of the casing, to the outlet 14. Passage 20 is adjustably restricted by a rotatable valve plug 21.

The partitions 1-5 and 16 have aligned ports therethrough, around which ports the material of the partitions is raised to provide annular knife-edged

valve seats

22 and 23. Cooperable with seat 22 is an inlet closure 24 (provided with a facing 24 of rubber-like material) having a stem 25 guidingly receivedin an opening through the hub 26 of a spider in the inlet port, the closure being biased toward seated position by the force of a light spring 27 compressed between it and an access cap 28 which forms the end wall of compartment 17.

Cooperable with seat 23 is an outlet closure 29 mounted on a member 30 which is reciprocable in an opening through the hub 31 of a spider in the outlet port. The outlet closure 29 has a central opening freely iitting the reduced left-hand portion of member 30 and, as shown in Fig. l, is held in engagement with a shoulder on the member by the force of a relatively stiff spring 32 compressed between the closure and the headed left extremityl of the member. This arrangement constitutes a yieldable, or biased lost-motion, connection between the outlet closure and member 30.

Between member 3d and the inlet closure 24' is a lostmotion connection of the snap-action type which comprises a llat arm 33 which is pivoted at its upper end on a pin 34 fixed to the casing, this arm being rockable between alternate positions determined by a pair of

stop elements

35 and 36, the stop element 35 being of the adjustable eccentric type. The lower extremity of arm 33 cooperates with the tip of an adjusting screw 25l in the stem portion 25 of closure 24.

For moving arm 33 abruptly between its stopped positions there is a bowed spring 37, of at metal, which bears at its top in a notch in the left edge of arm 33, and at its bottom in a notch in an off-set portion of another flat arm 38 behind arm 33 and conveniently pivoted on pin 34. The left edge of arm 38 is maintained continuously in engagement with the tip of an adjusting screw 30 in member 30 by the force of a spring 39, compressed between the casing and the lower end of arm 38, so that the position of the bottom of spring 37 is determined by the position of member 30. When arm 38 is rocked in either direction slightly beyond a posi'- tion wherein the opposite ends of the bowed spring 37 are aligned with pivot 34 the arm 33 is snapped to its alternate stopped position and held in that position by the bowed spring.

For operating the member 30 there is shown, by way of example, a luid pressure motor, preferably of the liquid-filled type, which comprises an eXpansible-contractible bellows 50 disposed in a recess in the outer wall of casing-section 12, and an interconnected thermal bulb 51 which, it is to be assumed, is arranged to respond to the temperature of a space heated by appara-tus supplied with fuel gas by way of the valve structure.

Bellows 50 is backed by a temperature-setting dialscrew 52 and has `a stem 53 which projects, sealingly, into,

the outlet compartment 18 and there engages a pivoted lever 54 which in turn engages another lever 55 whose free end bears against the left end of member 30. Member 30, levers 54, 55 and bellows-stem 53 are maintained continuously in interengagement by the force of spring 39 acting on the member through arm 38. The movement-amplifying lever arrangement is desirable in connection with control of temperature within a narrow range, .as in a room, but is not required when the temperature range is relatively wide, as in an oven.

In Fig. l the parts are shown in positions corresponding to low temperature at the thermal bulb, bellows 50 being so contracted that the outlet closure 29 is in wideopen position under the force of spring 39 acting through lever 38 and member 30, the inlet closure 24 also beingfully-open since the bottom of the `bowed spring 37 is at the left of its dead-center position and the force of this spring is thus effective to hold arm 33 against stop element 36 and the inlet closure unseated against the light force of spring 27. It is to be observed that if the cap 28 were arranged to limit opening of the inlet closure to the position shown in Fig. l, the stop element 36 could be eliminated. With closures 24 and 29 in fully open position gas can pass (as indicated by the flow-arrows) around the closures, and through the restricted passage 20, at a rate sufficient to produce a high-fire condition of the burner.

With rise of temperature .at the thermal bulb and corresponding expansion of the bellows, the member 30 is moved gradually to the right so that the outlet closure 29 is brought closer to its seat 23 to throttle the flow of gas. If the bulb temperature continues to rise the outlet closure is brought into engagement with its seat as shown in Fig. 2. It will be observed that spring 37 has not yet reached its dead-center position so that it is still effective to maintain the inlet closure unseated, and gas therefore passes to the burner by way of the restricted passage whose ow capacity is adjusted by plug 21 so that a predetermined low-fire condition of the burner is produced.

Under cold-weather conditions the operation is usually such that the outlet closure modulates between high-fire and low-tire positions. But if the bulb temperature continues to rise after the parts have reached their low-fire positions, the resultant farther expansion of the bellows effects movement of member 30 relative to the outlet closure, compressing spring 32, until arm 38 reaches a position wherein the bottom of spring 37 is just beyond its dead-center position (the position in which the ends of this spring are aligned with the pivot pin 34) so that under the force of spring 37 the arm 33 is snapped to its alternate position in engagement with stop 35, in which position the lower extremity of this arm is free from engagement by the stem of the inlet closure 24 so that the same seats under the force of spring 27 and iiow of gas to the burner is shut off. The parts are shown inthis condition in Fig. 3. To extend the range of low-fire operation of the burner the stop 36 is positioned so that snap-over` of arm 33 `occurs only after member 30 has moved through a substantial distance beyond the point at which the outlet closure seated.

When, due to the absence of heating, the member moves toward the left in response to cooling of the thermal bulb and contraction of the bellows, it engages the outlet closure and unseats it before arm 38 reaches a position corresponding to the dead-center position of spring 37 (this condition of the parts being shown in Fig. 4) so that when the inlet closure is finally snapped-open gas can pass around the outlet closure and through passage 270 in an amount suiiicient to ensure prompt lighting of the burner by the usual pilot-burner flame or other igniting means. The distance from its seat at which the outlet closure will be at the instant the inlet closure opens is determined `by the adjusted position of stop element 35. To avoid excessive noise at the burner when the gas is lighted, the stop is preferably adjusted so that the rate of initial flow of gas is only just suiiicient to ensure proper lighting.

While various forms of snap-action means can be employed according to this invention, snap-action means of the type (such as that shown) having stable equilibrium in both of its snapped positions is preferred since it can be adjusted more readily and accurately to determine (l) the extent of movement of member 30 after the outlet closure is seated and before the inlet closure is snapped closed, and (2) the extent of opening of the outlet closure before the inlet closure is reopened.

The specific embodiment of my invention herein shown and described is obviously susceptible of modication without departing from the spirit of the invention, and I intend therefore to be limited only by the scope of the. appended claims.

I claim as my invention:

1. In a valve structure: means defining a chamber having an inlet and an outlet; an inlet valve and an outlet valve controlling communication between said inlet and said chamber and between the chamber and said outlet,` respectively, and comprising respectively, an inlet closure movable into and out of engagement with an inlet valveseat and an outlet closure movable into and out of engage ment with an outlet valve seat; said chamber having a restricted passage connecting said outlet to said chamber at a point intermediate said valves; means for actuating said valves sequentially in response to variations of a controlling condition and comprising a member moved grad-` ually in opposite directions in response to variation of said condition in respective opposite senses; a first lostmotion connection between said member and said outlet closure; and a second lost-motion connection between the member and said inlet closure; said lost-motion connections being arranged so that when said condition varies in a given sense the outlet closure is seated before the inlet closure is seated so that fluid can then pass to said outlet only by way of said restricted passage, and so that when the condition subsequently varies in the opposite sense the outlet closure is unseated before the inlet closure is unseated so that fluid can pass relatively unrestrictedly from the chamber to the outlet when the inlet closure is sub sequently unseated.

2. A valve structure according to claim 1 and including means so biasing said first lost-motion connection that movement of said member relative to said outlet closure is permitted only while the outlet closure is in engagement with its seat.

3. A valve structure according to claim l wherein said second lost-motion connection comprises two-way snapaction means for moving the inlet closure abruptly into and out of seating position.

4. In a valve structure: a casing having an inlet and an outlet and, communicating respectively therewith, an inlet port and an outlet port; said casing having also a chamber interconnecting said ports, and a restricted passage connecting said outlet to said chamber at a point intermediate the ports; means forming a valve seat around each of said ports; an inlet closure and an outlet closure mounted for movement into and out of engagement with said inlet-port seat and said outlet-port seat, respectively, to control flow through the ports; means movable in response to Variation of a controlling condition for operating said closures sequentially and comprising a member moved gradually in opposite directions in response to variation of said condition in respective opposite senses; a first connection between said member and said outlet closure, said first connection being yieldable and arranged so that variation of said condition in a given sense effects seating of the outlet closure, so that fluid can then pass to said outlet only by way of said restricted pas sage, and subsequent movement of the member relative to the outlet closure while the outlet closure is seated; and a second connection between the member and said inlet closure arranged so that said subsequent movement of the member effects seating of the inlet closure, said second connection including means permitting limited lost-motion between the member and the inlet closure such that when the condition subsequently varies in an opposite sense the member can move relative to the inlet closure and effect unseating of the outlet closure before the inlet closure is unseated, so that fluid can pass relatively unre strictedly from the chamber to said outlet when the inlet closure is unseated.

5. A valve structure according to claim 4 wherein said second connection comprises two-way snap-action means for moving the inlet closure abruptly into and out of seating position.

6. In a valve structure: a valve casing having an elongated generally-cylindrical chamber, and an inlet and an outlet communicating with respective opposite ends of the chamber; said casing having also a restricted passage connecting said outlet to said chamber intermediate its ends; means forming a valve-seat around each of said ends of the chamber; an inlet and an outlet closure mounted for movement into and out of engagement with the respective ones of said seats to control ow through the casing; means movable in response to variation of a controlling condition for operating said closures sequentially and comprising a member moved gradually in opposite directions generally along the axis of the chamber in response to variation of said condition in respective opposite senses, a portion of the member being inside the chamber; a iirst connection between said member and said outlet closure, said irst connection being yieldable and arranged so that variation of said condition in a given sense effects seating of the outlet closure and subsequent movement of the member relative to the outlet closure While the same is seated; and a second connection between the member and said inlet closure arranged so that said subsequent movement of the member effects seating of the inlet closure, said second connection including means permitting limited lost-motion between the member and the inlet closure such that when the condition subsequently varies in an opposite sense the member can move relative to the inlet closure and eiect unseating of the outlet closure before the inlet closure is unseated.

7. A valve structure according to claim 6 wherein said second connection comprises two-way snap-action means for moving the inlet closure abruptly into and out of seating position.

8. A valve structure according to claim 6 wherein said member projects through an opening in said outlet closure.

9. A valve structure according to claim 8 wherein said second connection is inside said chamber,

10. A valve structure according to claim 6 wherein said seats face in opposite directions, and said second connection includes means for eecting movement of said inlet closure in directions opposite to the directions of accompanying movement of said member.

ll. In a valve structure: a valve casing having an elongated cavity therein; a pair of spaced-apart partitions dividing said cavity transversely to form an inlet and an outlet compartment at opposite ends of the cavity, and a chamber between the partitions; said casing having an inlet and an outlet communicating with the respective ones of said compartments, and a restricted passage connecting said outlet to said chamber; each of said partitions having a port therethrough provided with a valve seat, the one of said seats nearer said outlet compartment facing that compartment; an inlet closure and an outlet closure each mounted for movement along the axis of the cavity into and out of engagement with the respective ones of said seats to control flow through the casing, said outlet closure being located in said outlet compartment; means mounted on the casing and movable in response to variation of a controlling condition for operating said closures sequentially, comprising a member moved gradually along the axis of the cavity in opposite directions in response to variation of said condition in respective opposite senses, said member projecting through an opening in the-outlet closure and having portions within the outlet compartment and the `chamber; a first lost-motion connection between said member and the outlet closure and comprising a spring arranged to render the connection rigid while the outlet closure is unseated and to yield when the outlet closure is seated so as to permit movement of said member in a direction inwardly of the chamber while said condition is varying in a given sense; and a second lost-motion connection, inside the chamber, between the member and said inlet closure and arranged so that said movement of the member inwardly of the chamber effects seating of the inlet closure, said second lost-motion connection being arranged so that when the condition subsequently varies in an opposite sense the member can move relative to the inlet closure and effect unseating of the outlet closure before the inlet closure is unseated.

12. A valve structure according to claim 11 wherein said second lost-motion connection comprises two-way snap-action means for moving the inlet closure abruptly into and out of seating position.

13. A valve structure according to claim 11 wherein the inlet one of said seats faces said inlet compartment and said inlet closure is within the inlet compartment, and wherein said second lost-motion connection includes means for effecting movement of the inlet closure in directions opposite to the directions of accompanying movement of said member.

References Cited n the ile of this patent UNITED STATES PATENTS 2,253,866 Quoos Aug. 26, 1941 2,308,275 Gauger Jan. 12, 1943 2,608,349 Landgrof et al. Aug. 26, 1952