US2663502A - Refrigeration expansion valve and adjustment mechanism therefor - Google Patents

Description

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Dec. 1953 E. J. DILLMAN ETAL 2,663,502

REFRIGERATION EXPANSION VALVE AND ADJUSTMENT MECHANISM THEREFOR Filed Jan. 24, 1950 2 Shets-Sheet 1 INVENTORS BY u 71W ATTORNEY Dec. 22, 1953 E. J. DILLMAN ET AL 2,663,502

REFRIGERATION EXPANSION VALVE AND ADJUSTMENT MECHANISM THEREFOR Filed Jan. 24, 1950 2 Sheets-Sheet 2 FIG.6

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W ATTORNEY Patented ec. 22, 1953 REFRIGERATION EXPANSION VALVE AN'D ADJUSTMENT MECHANISM- THEREFOR Earnest J. Dillman and Thomas E. Noak'es, Detroit, Mich, assignors to Detroit Controls Corporation, Detroit, Micln,

Michigana corporation of Application January 24, 1950, Serial-No. 140,194

7 Claims. 1

This invention relates to new and useful improvements in refrigeration expansion valves and more particularly to adjustment mechanisms therefor.

One of the objects of this invention is to provide a refrigeration expansion valve of new and improved construction.

Another object is to provide a refrigeration expansion valve having a new and improved mechanism for adjustably varying certain of the operating characteristics of the valve.

Other objects will become apparent from time to time throughout the specification and claims as hereinafter related.

This invention comprises the new and improved construction and cooperative relation of parts which will be described more fully hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawings to be taken as part of this specification there are clearly and fully illustrated two preferred embodiments oi this invention in which drawings Figure 1 is a view in longitudinal central sec' tion of a refrigeration expansion valve embodying one form of this invention.

Fig. 2 is a detail sectional view of the operating diaphragm and supporting spider for the valve shown in Fig. 1,

Fig. 3 is a detail view of the adjustment mech-' upper and lower diaphragms respectively of the valve'shown in Fig. 6,

Figs. 9 and 10 are detail views of the adjustment mechanism for the valve shown in Fig. 6 and are similar to those disclosed in Figs. 3 and 4, Fig. 10 being taken on the section line Ill-40' of Fig. 6 and broken away for clarity, and

Fig. 11' is a detail plan view ofthe adjustment" member for the valve shown in Fig. 6.

Referring to the drawings by characters of reference and more particularly to Figs. 1 to 5inelusive, there is shown a refrigeration expansion valve generally designated as I comprising a'valve' casing 2 having an inlet passageil and an outlet passage 5.

closes with a cover member 5 a pressure chamber generally designated as l.

The casing 2 has an enlarged endportion 5 opposite the inlet end and which en-- There is a tubular projecting portion a which extends from the err-- 2.' larged' end portion 5 of the valve casing into the pressure chamber 1. The valve inlet 3 extends through a tubular member 9 which is threadedly secured in a bore [0' in the valve casing 2' which is al'in'ed with the bore of the tubular extension 3. Within the tubular member 8 there is provided a' valve seat member I I A spherical valve member 12' is positioned on the inlet side of the valve seat member l and is urged to engagement therewith by a spring l3 and a valve guiding member it which includes a polygonal guide plate. The valve member i2 is operated by a valve stem [5 which extends through the tubular projection t of the valve casing 2. and is guided in a tubular guide member [5 which is threadedly secured in the valve casing bore Hl'and' extends into the tubular projection 8. The valve stem i5 is packed against leakage through the guide member IE3 as at H, the packing being held in position by a spring l8 compressed by a threaded abutment member 59. The upper end wall 2% of the cover member 5 closing, the end portion 5 of the casing 2' has a diaphragm 2i and operating spider 22 extending thereacross and enclosing a power element chamber 23. There is provided a dishshaped plate member" 24 having a central aperture 25 which engages the cover member endwall' ill at its periphery to hold the diaphragm 2| andspider 22' in position, the'diaphragrn 2i having its peripheral edge bent'over the peripheral edge of the plate member 24 to secure itself and the spider 22' in position; A hermetic seal is accomplished by soldering the plate member and diaphragm to the cover 6 as at 26. Positioned against the underside of the diaphragm 2i and spider 22 and" engaging'theup'per end of the valve stem l5 there is provided a thrust transmitting plate member 21 which isengaged' by a spring 28' determining the operating force required for opening the valve and hencethesuperheat setting of the valve. A cylindrical member 29 is slidably positioned'on the tubularcasin'g extension 8 and has a cupped flange portion 30 receiving the lower end Thefiange 36 of the springof' the spring 28. supporting member ZQ-has two upturned ears 3; and'32 which are supported on the inclined surfa'oes' o'f'parallel upturned portions 33 and 34 respe'ctiv'elyof an adjustment member 35. The=adjustment' member 35 is disc shaped and has an elongated central aperture 38 providing a guide The screw 35? is provided with packing as indicated at II to prevent leakage of refrigerant from the valve, the end of the screw 39 being enclosed by a threaded cap member 42 closing the end of the bore in which the guide member 48 is secured. The pressure chamber I is communicable with the outlet passage l through a passage 43 providing an internal equalizer, although for some installations this passage might be eliminated and the chamber 1 connected by way of an external connection through the wall 5 or 6 and an external conduit to the outlet end of the refrigerant evaporator, this last-mentioned arrangement being commonly known as external equalization. Extending through an aperture in the upper wall 28 of the cover member 5 is one end of a capillary tube :14 which is soldered as at 55, the other end of which is connected to a responsive bulb element 45. The bulb element as, tubing M and power element chamber 23 are charged with a quantity of volatile refrigerant to an extent known in the refrigeration art as a liquid charge.

It should be noted that there are several distinct advantages obtained by the construction set forth herein whereby it is possible to construct individually a number of sub-assemblies which are eventually assembled into the complete valve thus providing a more efiicient and less expensive construction and assembly. In the construction of this valve the valve inlet assembly comprising the tubular threaded inlet member 9, valve seat II, valve member I2, valve guide I and closing spring I3 comprise a single unit which would be preassembled and threadedly connected in the bore I9 upon final assembly of the valve. This valve unit in addition to being the controlling valve for the flow of refrigerant also functions as a check valve since the valve member I2 is capable of having movement relative to and away from the operating stem I5. This check valve arrangement operates to prevent a reverse flow through the valve unless the pressure on the outlet side of the valve should exceed the pressure at the inlet by a predetermined amount determined by the scale of the closing spring I3, this condition being one which could practically never occur. The valve stem I5, guide I6, and its packing arrangement II, I8, I9 would likewise be separately assembled and inserted as a unit in the bore It for transmission of movement from the operating diaphragm to the valve member I2. The power element assembly comprising the cover member 6, plate member 24, diaphragm 2|, tubing 44, and bulb element 48 would also comprise a preassembled unit which would be installed directly on the end portion 5 of the valve body 2 and sealed thereon by peripheral soldering and an inturned casing flange portion as at 41. In this assembly the side wall of the casing cover portion 6 is rolled in around the periphery of the plate member 24 to hold it and the diaphragm 2| firmly against the casing end wall 29. It should be noted that by this con.- struction there is provided a tight mechanical seal at the lower peripheral edge of the plate member 24 against which bears the rolled in side wall or" the casing cover 6. There is also provided by this construction a camming or leverage action of the plate member 24 against the peripheral indentation or ridge 2% on the end wall 20 of the cover 5 which provides a second mechanical seal at that point. For purposes of this last-'mentioned assembly the soldered connection at 41 would require a solder having a ower melting-point than; the solder connection at 26 to prevent a melting of that connection during final soldering. The sleeve member 29 supporting the spring 28 is operable to have movement longitudinally of the tubular projection 8 to vary the compression of the spring 23,

and thus vary the differential of pressure across the diaphragm 2i required to open the valve. By this adjustment the superheat setting of the valve may be varied. For adjustment of the spring supporting member 29 the inclined surfaces of the ears 33 and 3d on the adjustment member 35 are movable by the screw as under the inclined ears 3I and $2 of the supporting member 2s. This adjustment provides an inclined plane or wedge action for spring adjustment. By this arrangement there is provided a simple mechanism for translating the longitudinal and rotary motion of the adjusting screw 39 into vertical movement of thesupporting member 29 for spring adjustment.

In the form of the invention shown in Figs. 6 to 11 the wedge and spring adjustment member is shown as applied to an expansion valve of the "liquid charged type having a pressure limiting arrangement. In this figure the valve is generally designated as I flI and comprises a valve casing or body I02 having an inlet I63 and an outlet Hi l. In the inlet I63 there is provided a tubular inlet member use which is threaded in the bore I536 which intersects the passageway extending to the outlet I0 3. In the member I05 there is a valve seat member 507 having cooperable therewith a spherical valve member I38 which is urged toward its seat by a spring IE9 and polygonal guide member I It. The inlet I03 opens to the tubular member I05 through an inlet fitting member I I I which holds in position a strainer IE2. The casing I02 has an enlarged end portion II3 which encloses an annular chamber I I I around a tubular casing projecting portion H5. The casing projecting portion II5 has a bore concentric with the bore I06 and alined with the bore through the valve seat member IIl'I. There is an operating valve stem II6 which engages the valve member I08 at one end and extends through the bore of the projecting casing portion II5. The valve stem HE and surrounding projection is provided with packing as at I I I which packing is held in position by a spring I I8 compressed by a packing nut I I 9. There is provided an internal aperture I29 in the casing I02 which provides for communication between the outlet passageway IM and the annular chamber H4. Closing the upper end of the annular chamber I Hi there is provided a diaphragm and supporting spider I2I and I22. The spider and diaphragm are held in position by an annular dish-shaped member I23 which is secured at its periphery by an inturned casing flange portion I24 and hermetically sealed as by solder. A cupshaped and cylindrical casing cover member I25 is positioned over the diaphragm I2I and is threadedly connected to the casing end portion II3 as at I 26. The cover member I25 has positioned across its upper end a diaphragm and supporting spider I2! and I28 which is secured in position by an annular dish-shaped member I29 hermetically sealed as by solder indicated at I33. The plate member I29 is secured in position and the diaphragms I21, I27 and spiders I22, I28 are secured to their respective plate members as described for the valve shown in Fig. 1. The diaphragm operating spring I3I is positioned within the space enclosed by the upper diaphragm I27 and the cup-shaped cover member I25. Within the, cover member I25, there is provided a thrust transmitting structure interposed between the diaphragms i2? and i2! and which comprises upper and lower cup-shaped members I32 and I33, connecting bolt I35 and spring ltd. The spring 135 holds the lower thrust transmitting member I33 against the head of the bolt [34 and is collapsible only upon occurrence of a predetermined pressure thereacross. The upper and lower thrust members i552 and 133 are positioned against thrust plates I36 and 131 respectively abutting the diaphragms i2? and 12L Opening into the space l28 enclosed. by the. cover I25 and the upper diaphragm I21 and soldered as at 139 is, one end of a capillary tube M9, the other end of which has positioned thereon the responsive bulb element. Ml. For adjustment of the force required to open the valve there is provided a spring i 42 in the. annular chamber I it abutting the thrust plate M3 on the diaphragm 12!. The spring [42 is supported by a cylindrical adjustment member Hid having a spring supporting flange M5,. The flange. I45 of the tubular member i id has a, pair of upturned and inclined ears its and M1 which ride on the inclined surfaces of supporting ears 548, and M9 respectively of an adjustment member I59. The adjustment member I58 has a pair of dimpled portions iiii which provide a sliding contact with the lower wall of the annular chamber lid for movement thereof. The member its, has an elongated central aperture 152 which permits movement transverse to the casing projection I is and has a downturned flange portion its into which fits an adjustment screw Hi l. The adjustment screw i l extends through an aperture in the side wall of the casing and is provided with packing as at !55 and is held in position by a threaded bearing member 56. The end of the adjustment screw Hid is covered by a threaded cap member I57 closing the opening from which the adjustment screw extends.

In this form of valve the spring adjustment for variation of valve superheat setting is substantially the same as that described for the valve shown in Fig. l. The turning of the adjustment screw in this arrangement causes the adjusting member 556 to be moved longitudinally of the screw thus varying the position of the inclined surfaces of the supporting ears MB- and M8 to provide an adjusting movement of the spring supporting member [46. The collapsible thrust member provided between two operating diaphragms permits the lower diaphragm [2! to be compressed toward the upper diaphragm at a predetermined maximum pressure in the, valve, the lost motion between the diaphragms being taken up by the collapsible spring member. The power element bulb Mi, tube I i-ii and power element space or chamber L38 would be filled with a liquid charge of refrigerant for temperature response. The collapsible spring arrangement 135 requires a predetermined collapsing force and thus provides the equivalent of a gas charged valve.

Having thus described the invention what is claimed and desired to be secured by Letters Patent of the United States is:

1. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve member controlling flow of refrigerant through said passageways, an operating diaphragm in said casing arranged for actuation of said valve member, a spring opposing movement of said diaphragm in a valve opening direction, said casing having a guide projection extending toward said diaphragm, a supporting member for said spring slidably guided on and operable to have sliding movement longitudinally of said guide projection, a wedge member arranged to have movement transversely to said guide projection and cooperable with said supporting member upon movement to vary the position thereof on said guide projection thereby to vary the compression of said spring, and means to adjust the position of said wedge member.

2. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve member controlling flow of refrigerant through said passageways, said casing having a portion defining a chamber communicable with refrigerant on the outlet side of the valve, a diaphragm closing said chamber and arranged for actuation of said valve member, means forming with said diaphragm a thermostatic power elementv for actuating said valve member, a spring opposing movement of said diaphragm in a valve opening direction, said casing having a tubular projection extending into said chamber, a sup: porting member for said spring slidably guided on and operable to have sliding movement longitudinally of said tubular projection, a wedge member in said chamber arranged to have movement transversely to said tubular projection and cooperable with said supporting member upon movement to vary the position thereof on said tubular projection thereby to vary the compression of said spring, and means to move said wedge member.

3. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve member controlling flow of refrigerant through said passageways, said casing having a portion defining a chamber communicable with refrigerant on the outlet side or" the valve, a diaphragm closing said chamber and arranged for actuation of said valve member, means forming with said diaphragm a thermostatic power element for actuating said valve member, a spring opposing movement of said diaphragm in a valve opening direction, said casing having a tubular projection extending into said chamber, a sup porting member for said spring, said supporting member being slidably guided on and operable to have sliding movement longitudinally, of said tubular projection, a wedge member in said chamber arranged to have movement transversely to, said tubular projection and underlying said supporting member and cooperable therewith upon movement to vary the position thereof on said tubular projection thereby to vary the com pression of said spring, and a threaded adjustment member extending through a wall of said casing into said chamber and engageable with said wedge member for adjusting the position thereof.

4. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve member controlling flow of refrigerant through said passageways, said casing having a portion defining a chamber communicable with refrigerant on the outlet side of the valve, a diaphragm closing said chamber and arranged for actuation of said valve member, means forming with, said diaphragm a thermostatic power element for actuating said valve member, a spring opposing movement of said diaphragm in a valve, opening direction, said casing having a tubular projection extending into said chamber, a tubular supporting member guided for longitudinal movement on said projection and having a flange receiving and supporting one end of said spring, said flange having. a. pair of inclined upturned cars on oppositasides thereofl an adjustment member slidable along the lower end wall of said chamber transver ely to said tubular projection, said adjustment member having a pair of up turned ears having inclined faces forming wedges cooperable one with each of said flange ears and operable upon said transverse movement to adjust the position of said supporting member on said tubular projection thereby to vary the compression of said spring, and means to move said adjustment member through said transverse movement.

5. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve member controlling flow of refrigerant through said passageways, said casing having a portion defining a chamber communicable with refrigerant on the outlet side of the valve, a diaphragm closing said chamber and arranged for actuation of said valve member, means forming with said diaphragm a thermostatic power element for actuating said valve member, a spring opposing movement of said diaphragm in a valve opening direction, said casing having a tubular projection extending into said chamber, atubular supporting member guided for longitudinal movement on said projection and having a flange receiving and supporting one end of said spring, said flange having a pair of inclined upturned ears on opposite sides thereof, an adjustment member slidable along the lower end wall of said chamber transversely to said tubular projection, said adjustment member having a pair of upturned ears having inclined faces forming wedges cooperable one with each of said flange ears and operable upon transverse movement to adjust the position of said supporting member on said'tipbular projection thereby to vary the compression of said spring, and a threaded adjustment member extending through a wall of said easing into said chamber and engageable with said adjustment member for moving said wedges relative to said flange ears.

6. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve seat and port in said inlet passageway, a valve member cooperable with said seat to control flow through the valve, said casing having an enlarged end portion having an open-ended cylindrical'cavity with a smooth end wall at one end, a thermostatic power element having a charge of volatile temperature responsive liquid therein and including a responsive bulb element, and a cover member and operating diaphragm closing the open end of said casing cavity, said casing having a tubular projection alined with said inlet passageway and Valve port and extending from the end wall of said cavity into the chamber defined by said cavity, a valve stem guided within said projection and cooperable at one end with said valve member and at the other end with said operating diaphragm for transmit ing movement to said valve member, a spring in said chamber surrounding said projection and I cooperable with said diaphragm to resist moveelongated central opening to permit movement transverse to, said ,projection, said adjustment 8 member having a pair of upturned ears having inclined faces forming wedges registering one with each of the ears on said flange, said adjustment member being operable upon movement relative to said flange ears to vary the position of said supporting member on said tubular projection, and a threaded adjustment member extending through a wall of said casing into said chamber and engageable with said adjustment member for moving said wedges relative to said flange ears.

7. In a refrigeration expansion valve, a valve casing having inlet and outlet passageways, a valve seat and port in said inlet passageway, a valve member cooperable with said seat to control flow through the valve, said casing having an enlarged end portion having an open-ended cylindrical cavity with a smooth end wall at one end, a thermostatic power element having a charge of volatile temperature responsive liquid therein and including a responsive bulb element, and a cover member and operating diaphragm closing the open end of said casing cavity, an an nular dish-shaped plate member securing the periphery of said diaphragm against said cover member and providing a stop limiting downwart movement of said diaphragm to prevent rupture thereof by high pressures in the power element, said casing having a tubular projection alined with said inlet passageway and valve port and ex tending from the end wall of said cavity into the chamber defined by said cavity, a valve stem guided within said projection and cooper-able at one end with said valve member and at the other end with said operating diaphragm for transmitting movement to said valve member, a spring in said chamber surrounding said projection and cooperable with said diaphragm to resist movement thereof in a valve opening direction, a supporting member for said spring having a tubular portion guided on said tubular projection and having a flange receiving and supporting one end of said spring, said flange having a pair of upturned inclined ears on opposite sides thereof, an adjustment member having a flat base portion slidable along said cavity end wall and having an elongated central opening to permit movement transverse to said projection, said adjustment member having a pair of upturned ears having inclined faces forming wedges registering one with each of the ears on said flange, said adjustment member being operable upon movement relative to said flange ears to vary the position of said supporting member on said tubular projection, and a threaded adjustment member extending through a wall of said casing into said chamber and engageable with said adjustment member for moving said wedges relative to said flange ears.

EARNEST J. DILLMAN, THOIVIAS E. NOAKES.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,536,461 Wadsworth May 5, 1925 2,079,579 Shrode May 4, 1937 2,215,947 Wile Sept. 24', 1940 2,249,101 W'ile July 15, 19%1 2,306,768 Wile Dec. 29, 1942 2,435,716 Kearney Feb. 10, 1948 2,520,386 Dillman Aug. 29, 1950

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