US2947324A - Reversing valve for reversible refrigerating system - Google Patents

Description

1960 K. K. COOPER ETAL 2,947,324

REVERSING VALVE FOR REVERSIBLE REFRIGERATING SYSTEM Filed April 17, 1958 3 Sheets-Sheet 1 IN V EN TORS K. COOPER Q DONALD W LYNCH BY )2? KENNETH THEI R ATTORNEY Aug. 2, 1960 K. K. COOPER Em 2,947,324

REVERSING VALVE FOR REVERSIBLE REFRIGERATING SYSTEM Filed April 17, 1958 3 Sheets-Sheet 2 PIC-3.2

INVENTORS ,./\J KENNETH K. cOoPER a DONALD W. LYNCH THEIR- ATTORNEY Aug. 2, 1960 K. K. COOPER ETAL 2,947,324

REVERSING VALVE FOR REVERSIBLE REFRIGERATING SYSTEM Filed April 17, 1958 s Sheets-Sheet 3 FIG. 4

FlG.5

INVENTOR. KENNTH K. COOPER 8 DONALD vv. LYNCH THEI R ATTORNEY Unite REVERSING VALVE FOR REVERSIBLE REFRIGERATIN G SYSTEM Filed Apr. 17, 1958, Ser. No. 729,108 3 Claims. ((11. 137-62529) The present invention relates to reversible refrigerating systems and more particularly to a reversing or transfer valve for effecting reversal of refrigerant flow through the heat exchanger components of the system.

One object of the present invention is to provide a new and improved reversing valve for directing the flow of refrigerantthrough a reverse cycle refrigerating system.

A further object of the invention is to provide a reversing valve of simple and low cost construction and which does not require unloading or pressure equalization. of .thetsystern to facilitate operation of the valve.

A further object of the invention is to provide an automatic reversing valve including a two-Way pressure-actuated piston arrangement for reversing the valve and means operated upon the movement of the valve to one or the other of its two operating positions, for equalizing the pressures'on opposite sides of the piston and conditioning theflvalve mechanism for a subsequent operation.

Further objects and advantages of the present invention will become apparent as thefollowing description proceeds, and the features of novelty which characterize States Paten n the invention will be pointed out with particularity in the claims annexed cation. In carrying to and forming a part of this specifiout the objects of. the present invention there is provided a reversingvalve which is adapted to direct the flow of high pressure refrigerant from a compressor to either of two series-connected heat exchangers and to return low pressure refrigerantffroni the other of theheat exchangers to the compressore. The valve com prises avalve plate and. a casing which cooperate to define a gas tight valve housing. The casing has ahigh pressure refrigerant inlet. port communicatingwiththe housing While the valve t plate includes a surface within the housing which forms atvalve seat having therein a suction or outlet port for connecting the valve to the compressorI suction line and two additional ports respectively connecting the housing to each of the two heat exchangers. The heat exchanger ports are spaced equidistant from the suction port so that a valve member having one end connected to the suction port and the other end slidably supported on the valve seat and which is mounted for pivotal movement about the suction port can connect the suction port to either one or the other of the two heat exchanger ports. By this arrangement, high pressure refrigerant entering the housing through the ,inlet port passes out of the valve housing'through which ever heat exchanger port is not covered by the valve memher. and to the heat exchanger connected to that port while low pressure refrigerant from the other heat exchanger is directed through the valve member and back to the compressor through the. suction port. For the purpose of moving the valve member from one or theother of its two operating positions, there is provided a cylinder outside the housing and between the suction and, heat exchanger ports, and a piston'slidably arranged. within the cylinder and dividing the cylinder into a controLcham- 2,947,324 r Patented Aug. 2, '1 960 her and a second chamber. The piston is operatively connected to the valve member by'means of a lever extending through the valve plate andpivotally mounted therein. By creating a pressure differential across the piston, the valve member operatively connected thereto is actuated to one or the other of its operative positions and for this purpose, means are provided for connecting one of the chambers within the cylinder either to the high pressure .line connected to the inlet port or to the low pressure line connecting the outlet or s'uction port of the valve to the, compressor. In order to equalize the pressures across the piston after such actuation of thevalve member and to condition the reversal of the valve-member, there is provided a slide valve operated by the valve member and designed to control the flow of refiigerant through a passageway leading from the second chamber to the valve housing. -In one position ofthe slide valve, the housing end of the passage is-in communication witha second passage having one end opening into the valve seat and the other connected to the suction port whilein a second position of the slide valve, 'the first mentioned passage is in direct communication with the high. pressure refrigerant in the housing. The operation of the slide valve is such that after completion of the piston stroke, refrigerant at the same. pressure as that employed in the control chamber for the purpose of efiecting the stroke is introduced into the second chamber thereby equalizing the pressures across the. piston and conditioning thecontrol cylinder, for a subsequent operation of the piston, to reverse the positionof the valve member. For a better understanding of the invention, reference may behad to the accompanying drawing in which: 3 Fig. l is a diagrammatic illustration of the heat pump of reversible refrigerating system provided with a reversing valve embodying the present invention; a

Fig. 2 is an enlarged view, partially in section, oftthe valve of thepresent invention; A

Fig. 3 is an elevational sectional view. along line 3 3 Fig. 5 is a1 detailed sectionalview along linieS-S of Fig. illustrating the slide valve in one operating posi tion;,- v r 'Fig. 6 is a View si'milartdFig. 5 showingt-ajsecorid 'operative position of the slide valve illustrated in" Fig; 5;

and t V a Fig.7 is a sectional view along line 7-7 of Fig. 5. LgdRiCI'Ifll'lgllOW to Fig," llof the drawing, thet'reversible refrigerating" system disclosed comprises an indoor heat exchangerrl and an outdoor heat exchanger 2 which are connectedin series'through an expansion valve 3 whereby the heat exchanger 1 can be employed for either heating or cooling mean from within an enclosure depending upon the direction of fiow of refrigerant through the two heat exchangers; h 1 Refrigerant is circulated through the heat exchangers by means of a compressor 4 while the valve 5, forming the subjectmatter of'the present invention, controls the direction of flow of refrigerant through the heat exchanger so that the heat exchangers 1 can function either as the condenser or as the evaporator, component of the refrigerating system. In this system high pressure refrigerant from the compressor flows throughthe compressor discharge line 7 and through the valve S'to either the indoor heat exchanger 1 through the indoor conduit 8 or to, the outdoor heat exchanger 2 through the conduit 9. Low pressure refrigerant from the heat exchanger functioning as the evaporatorreturns to the compressor through the valve 5 and the suction line 11.: t a

Referring now more particularly to Figs. 2, 3,. and 4 of the drawingspthe reversing valve 5 of the "p'resent invention comprises a valve plate 12 and a casing 14 which cooperate to form a gas tighthousing 15 intowhich high pressure refrigerant is; introduced through the inlet port, 16 connected to the compressor discharge line 7.

The valv'e plate 12forrning one wall of the housing 15' is preferably composedjof a plurality of layers for reasons which will be given hereinafter and includes a smooth. flat inner. surface forming a valve seat 17 within the housing 15. Provided in the flat surface portion of the valve seat'17" are spaced heat exchanger ports, the porth18 communicating with the heat exchanger conduit 8' and the port v19 communicating with the heat exchanger conduit.9. Spaced equidistant from these two ports is a suction port20 which is in communication with the suc- 'tion lijne;11' and which preferably comprises a, tubular portion extending slightly above the surface of the valve seat 17.

Forthe purpose of connecting one or the other of the two heat exchanger 'ports with the suction port 20, there is provided: a valve member 21 having one end 22 pivotally mounted on the upwardly extending portion of the suction port 20 and the other end 23 slidably supported on the valve seat 17 whereby the suction port 20 can be connected through the substantially U-shaped passageway 24 within the valve member 21' with either of the heat exchanger ports 18" and 19 by pivotal movement of the valve member 21 about the suction port 20. A tension spring 26 having one end extending into the passage 24 and connected to the valve member 21 and. the other end extending through the suction port 20 and connected by means of a pin 27 to the walls of the port servesto hold the valve member 21 in engagement with the port 20 and the valve seat 17 regardless of the positioning of the valve 5. Preferably, this spring 26 is positioned vcentrally of the port 20 and hence in line with the axis of rotation of the valve member 21. Means for limiting movement of the valve member 21 in either direction so that the passage 24 is'in line with one or the other of two heati exchanger ports '18 and 19 is provided in the form'of flanges 29 and30v extending outwardly there is provided a slide valve 51 slidably arranged on the surface of the valve seat 17 beneath the flange 29 for connecting the chamber 35 through a passage 52 with either the low or high pressure sides of the refrigerating system only after the valve member 21 has completed most of its travel from one operating position to the other. The slide valve 51 is held in sliding engagement with the valve seat 1.7..by a bracket 54 secured to the valve seat by bolts 55 and a spring collar 57 which bears against the lower side of the. bracket 54. .A slot 58 through which the projection 59 forming a part of'the valve 51 extends. is'provided in the bracket 54 for the purpose of defining thepath and limiting. the movement of the valve 51 relative to the valve seat 17.

For the purpose of connecting the passage 52 with low pressure or suction refrigerant there is provided in the valve plate 12 a suction gas passage 61 which is indicated in Figs. 2, 5 and 6 and which connects at one end to the suction port 20 and at the 'other'end opens through port 62 onto. the valve seat 17. In order to form'the suction passage 61, the valve plate 12 comprises a plurality of layers, the upper layer forming the valve seat 17 having the passage or opening 62 provided therein while the next layer indicated by the numeral 64 has a connecting slot extending from the lower end of the opening 62 to the suction port 20. r

7 travel of the valve member 21 in either direction, the

Means for shifting the valve from oneto the 'other of 'its'two operating positions includes a piston 32 slidably arranged within a cylinder 3.3,the piston 32 dividiiig the cylinder into a control chamber 34 and a second or pressure equalizing chamber 35. As indicated in Fig.-

ot'ally mounted in the valve plate 12 employing a gas tight packing 36 and which has one'end 37 loosely disposed in a slot' 38 in the piston 32and' the other end 39 looselydisposediin a slot 40 on the bottom portion of the valvemember 21. V 7

By this arrangement it will be seen that movement of the piston from one end to the other of the cylinder 33, which extends in a.direction generally parallel to the direction of travel of the end 23 of the valve member, causes the valve member 21 to pivot about the suction line 20 in theopposite direction, travel of the valve member in either direction be limited by the flanges 29 and 30. In order to obtain this valve actuating movement of the piston 32 withinthe cylinder 33, the control chamber 34 is connected through a control tube. 43 to either the high pressure or discharge line 7 from the compressor of the suction line 11 depending upon the then existing value of the pressure in the equalizing chamber 35. As is shown in Fig. 1 the control tube 43 can be connected by a three-way solenoid valve 45 to either the compressor discharge line 7 through a conduit 46 or to the suction line 11 through the conduit 47.

In order to equalize the pressures on. opposite sides Actuating of the slide. valve 51 by the valve member 21, is obtained by means of a slot or recess 67 of arcuate shape in the flange 29 which encompasses the projection 59 and is of a length such that near the end of the position of the slide valve 51 will be reversed. In one position of. the slide valve 51, the recess 71 formed in the lower part of 'the valve overlies the suction port connection 62 and the passage 52 to the cylinder chamber 7 35 as shown in Fig; 5 so thatthe chamber 35 is in communication with the low or suction pressure side of the system and hence at a lower suction pressure. In the reverse positionof the valve 51 as shown in Fig. 6, the passage 52 is in communication with the interior of the housing 1 5so that the chamber 35 will be at the higher discharge pressure ofthe system since the housing 15 is always at this pressure. Io. provide for this lattercommunication, it may bedesirabl e to form the spring collar 57 with a plurality of'slots 73 so that open communication is obtained between the passage 52 and the housing through the slot 58: provided in the bracket 54.

' Byfthisarrangement, movement of the'valve member 24 to' either of its two operating positions is assured even in th ose cases where'the valve may be in an intermediate position as for example as a result of jiggling of the struc- With thevalve in the position shown in Figs. 2, 3 ,4, and 5, the control chamber 34 is I at suction pressure as is also the chamber 35 since this chamber is connected to the suction line through the auxiliary valve 51 and passages 52 and 61. The pilot valve 45connects the line 43' to the suction conduit 11 through the line 47. The indoor coil 1 is functioning as a condenser and the outdoor coil 2 as an evaporator so that the system is conditioned for heating the enclosure which it serves. V i

When cooling is called for, the solenoid valve 45 is actuated to connect the control chamber 34 to high or discharge pressure. This high pressure drives the piston 32 to the right as viewed in Fig. 4 thus causing the lever 41 to drive the valve member 19 to the left and into its operatingposition with regards to the heat exchanger port18. During this transfer of the valve member 19 both of the heat exchanger ports 18 and 19 are exposed for a short time to: the high pressure existing within the housing 15 so that there is at least some equalization angst;

. t t As to the operation (of'the auxiliary valvesl, it is not until the main valve member 19' has been shifted to practically the end of its travel, for example, into communication with the port 18, that the walls of the slot 67 engage the projection 59 and cause the auxiliary valve 51 to move to the position shown in Fig. 6, that is, the position in which the passage 52 is in communication with the higher or discharge pressure gas within the housing 15. Thus during this transfer, the second chamber 35 is at suction pressure to maintain a positive pressure difierential across the pistonuntil the valve transfer is substantially complete at which time the shift of the auxiliary valve 51 then connects the chamber 35 to discharge pressure in order to equalize the pressures on the opposite sides of the piston 32 within the cylinder 33 and set up the pressure conditions in the cylinder 34 required for the subsequent reversal of the valve.

, In order to shift the valve to its position connecting the compressordischarge with heat exchanger, the control chamber 34 is connected to the, suction line 11 through the valve 45 and'with the delayed action of the auxiliary valve 51 the resultant pressure differential across the piston 32 shifts the valve member 21 into operative position withport 18. Thus it will be seen that while both shifting operations are dependent upon the pressure differentials across the piston 32, they are independent of the pressure conditions existing within the housing 15 although the high or discharge pressure within the housing 15 does help to maintain the valve member in seated relationship on the valve seat 17.

While there has been shown and described a particular embodiment of the present invention, it is to be understood that the invention is not limited thereto, and it is intended by the appended claims to cover all modifications within the true spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A reversing valve comprising a valve plate and a casing defining a gas tight housing, said valve plate including a surface within said housing forming a valve seat, said casing having a high pressure inlet port, said valve seat having a plurality of ports opening into said housing and including a low pressure outlet port and two additional ports spaced equidistant from said low pressure port, a valve member having a valve passage communicating at one end with said low pressure outlet port, the other end of said valve member being slidably supported on said valve seat, said valve member being pivotally mounted adjacent said one end of said passage for pivotal movement about said low pressure outlet port for move ment of the other end of said valve passage between two limiting positions communicating with said respective additional ports, and means for actuating said valve member from either of said limiting positions to the other comprising a cylinder generally disposed outside said housing between said low pressure outlet port and said additional ports and extending in a direction substantially parallel to the direction of movement of said other end of said valve passage between said additional ports, a piston slidably disposed in said cylinder and dividing said cylinder into a control chamber and a second chamber, a lever pivotally supported by said valve plate and having one end in engagement with said valve member and the other end engaged by said piston whereby movement of said piston efiects pivotal movement of said valve member to either of said positions, means for creating a pressure differential across said piston to eifect movement thereof within said cylinder comprising means for connecting said control chamber with either said inlet port or said low pressure outlet port and means for equalizing the pressures across said piston upon completion of a piston stroke comprising a first passage extending through said valve plate and having one end commuunicating with'said second chamber and the other end opening into said housing, a low pressure passage extending position in which the pressure in said second chamber becomes the same as that existing in said control chamher.

2. A reversing valve comprising a gas-tight housing including a flat surface Within said housing forming a valve seat, said housingincluding an inletport, said valve seat having a plurality of ports opening into said housing and including an outlet port and two spaced apart additional ports spaced equidistant from said outlet port, a valve member slidably supported on said valve seat and having a valve passage communicatingat one end with said outlet port, said valve member being pivotally mounted adjacent said oneend of said passage for pivotal movement about said outlet port for movement of the other end of said valve passage into operative position with one or the other of said additional ports, spring means for maintaining said valve member in engagement with said valve seat, and means for actuating said valve member from either of said operative positions to the other comprising a cylinder disposed between said outlet port and said additional ports and extending in a direction generally parallel to the direction of travel of said other end of said valve passage, a piston slidably disposed in said cylinder and dividing said cylinder into a control chamber and a second chamber, a lever having one end in engagement with said valve member and. the other end engaged by said piston, means for selectively connecting said control chamber to said inlet port or to said outlet port for efiecting movement of said valve member from one operative position to the other, and means for equalizing the pressures across said piston when said valve member approaches said other position comprising a first passage extending through said valve plate and having one end communicating with said second chamber and the other end opening into said housing, a second passage extending from said outlet port through said valve plate and terminating on the face of said valve plate adjacent said first passage, a slide valve slidably arranged on said valve seat in operative relationship with the valve seat ends of said first and second passages, a slot in said valve member, a projection on said slide valve extending into said slot, said slot being of a length such that as said valve member approaches either of its operating positions an end of said slot engages with the projection to actuate said slide valve to a position in which the pressures in the two chambers are equalized.

3. A reversing valve comprising a valve plate and a casing defining a gas-tight housing, said valve plate including a surface within said housing forming a valve seat, said casing including an inlet port, said valve plate including an outlet port and two additional ports spaced equidistant from said suction port, said outlet port having an annular end portion extending into said housing, a valve member having a passage communicating at one end with said outlet port, said valve member being slid ably supported on said valve seat and pivotally mounted on said annular end portion of said outlet port for pivotal movement thereabout to bring the other end of said passage into communication with either of said additional ports, means on said valve member for engaging said casing to limit pivotal movement of said valve member to a first operating position communicating with oneof said additional ports and a second operating position communicating with the other of said additional ports, a tension spring for maintaining said valve member in engagement with said valve seat, said spring having one end extending into said passage and connected to said ama e between said outlet port and said additional ports and extending in a direction substantially parallel to the direction of movement of said other end of said passage between said additionalports, a piston slidably disposed in said cylinder and dividing said cylinder into a control chamber and a second chamber, a lever pivotally supported by said valve plate and having one end in engagement with said, valve member and the other end engaged by said piston whereby movement of said piston will effect pivotal movement of said valve member to either of said operating positions, and means for creating a pressure differential across said piston to move said valve member from one operative position to the other comprising means ;for selectively connecting said control chamber to either said inlet port or said outlet port and means for equalizing the pressures across the piston upon completion of a valvemember movement comprising an equalizer passage extending through said valve plate and having one end communic ting t said s con h mb a d theother end op nin nto a ou on aid valve seat; a second passage extending from said outlet port through-said valve plate and'terminating on the face/of said val-Y plate. a j ent S id firs pas g .a l e valv slidably arranged'on said valve seatin operative relation: ship w th thelhous ng'en i equa e Pa a e; a

slot in said valve member, a projection on said slide valve I extending into said slQt, said slot bfi ng of a length such that as-said valveineinber approaches either of its opcratingpositions, 'an end of said slot engages said projecv tion to actuate said slide valve to a position in which said second chamber is broughtto the same pressure as said control chamber.

References Cited'in the file of this patent V V UNITED STATES PATENTS

Images