Switching valve

Abstract

Provided is a switching valve capable of reducing generation of large frictional force.　A switching valve V comprising a housing 10 in which an inflow passage Pi and an outflow passage Pe are provided, and a valve body 20 that is rotatably provided in the housing 10 and that switches between the inflow passage Pi and the outflow passage Pe, the pressure acting on the valve body 20 changing, wherein the valve body 20 is rotatably guided in relation to a support shaft 14 provided in the housing 10, and an elastic means 30 is disposed between the valve body 20 and a seat part 17 of the support shaft 14.

Description

Switching valve

[0001] The present invention relates to a switching valve, for example, a switching valve that opens and closes a flow path through which a refrigerant flows or switches the flow path.

[0002] In various industrial fields, refrigerant circuits are used in which a refrigerant supply source is connected to a refrigerant load such as a refrigerant-operated device or a heat exchanger by a flow path. Some of these refrigerant circuits are provided with a switching valve for opening and closing the flow path or for switching the flow path.

[0003] For example, the switching valve of Patent Document 1 is mainly composed of a casing, a slider, and a spring. The casing is connected to a discharge pipe through which refrigerant discharged from the compressor flows, and a suction pipe through which refrigerant drawn into the compressor flows. The casing also has two ports formed in addition to the ports connected to the discharge pipe and the suction pipe. The slider is disposed within the casing and is rotatable. The spring is disposed between the valve seat and the slider in the casing.

[0004] Because the pressure difference between the inside and outside of the slider is large when the compressor is operating, the slider is pressed tightly against the valve seat against the biasing force of the spring, thereby dividing the flow path between one of the two ports and the port connected to the discharge pipe, and the other of the two ports and the port connected to the suction pipe.

[0005] Furthermore, when the compressor is stopped, the pressure difference between the inside and outside of the slider is small, so the slider is pushed away from the valve seat by the spring, preventing large frictional forces from occurring between the slider and the valve seat when the slider rotates.

[0006] Japanese Patent Application Laid-Open No. 62-288780 (page 4, Figure 1)

[0007] In the switching valve of Patent Document 1, the spring contacts the valve seat regardless of whether the pressure acting on the slider changes, which can cause the spring to slide against the valve seat as the slider rotates, and can also cause large frictional forces to be generated between the spring and the valve seat as the slider approaches and moves away from the valve seat.

[0008] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a switching valve capable of reducing the generation of large frictional forces.

[0009] To solve the above problems, the present invention provides a switching valve comprising: a housing having an inlet passage and an outlet passage; and a valve element rotatably disposed within the housing for switching between the inlet passage and the outlet passage, wherein the pressure acting on the valve element varies; the valve element is rotatably guided relative to a support shaft disposed within the housing, and a resilient means is disposed between the valve element and a seat portion of the support shaft. This reduces the generation of large frictional forces between the valve element and the housing even when the pressure acting on the valve element varies. This allows the valve element to be positioned accurately in a predetermined position.

[0010] The support shaft may be fixed to the housing, and a bearing may be interposed between the support shaft and the valve body, thereby allowing the valve body to move smoothly along the support shaft.

[0011] The bearings may be disposed on both axial sides of the support shaft with the resilient means interposed therebetween, thereby enabling the valve body to move more smoothly along the support shaft.

[0012] The support shaft may be provided with a stopper that restricts the extension of the resilient means, thereby preventing the valve element that is pushed and moved by the resilient means from coming into contact with other objects.

[0013] The resilient means may include a spring and a disk that is in sliding contact with the valve body. In this case, the disk is in sliding contact with the valve body when the valve body rotates, thereby reducing the generation of large frictional force between the resilient means and the valve body.

[0014] The support shaft may be disposed so as to penetrate from the exterior to the interior of the valve body and overlap with the outflow passage in the axial direction of the support shaft. In this way, the support shaft, which is installed to protrude into the valve body, can function as a guide for fluid flowing toward the outflow passage. This facilitates smooth movement of fluid toward the outflow passage, making it difficult for the valve body to shift position and making it easier to maintain the valve at a predetermined valve position.

[0015] It is a schematic diagram showing a refrigerant circuit to which a switching valve of an embodiment according to the present invention is applied. It is a perspective view of the switching valve of the embodiment. It is a cross-sectional view of the switching valve in a state in which the space between the valve body and the housing is sealed. It is a cross-sectional view of the switching valve in a state in which the valve body is floating. It is an enlarged view of a part of Figure 4. It is a top view showing the valve body rotated from a first rotation position to a second rotation position.

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve according to the present invention will be described below with reference to the following examples. While a refrigerant switching valve will be described as an example of the switching valve, the switching valve may be a valve for switching a fluid other than a refrigerant.

[0017] A refrigerant switching valve according to an embodiment will be described with reference to Figures 1 to 6. In the following description, the top and bottom of Figure 3 will be taken as the top and bottom of the refrigerant switching valve.

[0018] As shown in Fig. 1, the refrigerant switching valve V of the present invention is a four-way valve provided in a refrigerant circuit 1. In addition to the refrigerant switching valve V, the refrigerant circuit 1 is provided with a compressor C, a first load L1, and a second load L2. The compressor C discharges a discharge fluid Pd, which is a compressed, high-pressure refrigerant, and draws a suction fluid Ps, which is a reduced-pressure, low-pressure refrigerant.

[0019] The refrigerant switching valve V is provided with an inlet port Pi as an inlet path connected to the discharge side of the compressor C through a discharge path 2, a first port P1 connected to a first load L1 through a first path 3, a second port P2 connected to a second load L2 through a second path 4, and an outlet port Pe as an outlet path connected to the suction side of the compressor C through an outlet path 5. The first load L1 and the second load L2 are connected through a third path 6.

[0020] The refrigerant switching valve V switches whether the discharge fluid Pd sent out from the compressor C passes through the first load L1 and then the second load L2, as shown by the solid line, or the discharge fluid Pd passes through the second load L2 and then the first load L1, as shown by the dashed line. The refrigerant switching valve V will be described in detail below.

[0021] 2 and 3, the refrigerant switching valve V is mainly composed of a housing 10, a valve element 20, a spring means 30 (see FIG. 3), and a drive source 40 (see FIG. 2). In FIGS. 2 and 3, the valve element 20 is in a first rotation position, communicating the inlet port Pi with the first port P1 (see FIG. 2) and communicating the second port P2 (see FIG. 3) with the outlet port Pe (see FIG. 3).

[0022] The housing 10 is mainly composed of a case 11 and a stator 12 .

[0023] 2, the case 11 is made of resin and includes a main body 11a and a socket 11b. The case 11 may be made of metal, and the material may be changed as appropriate.

[0024] The main body 11a is a cylindrical body with a ceiling that opens downward, and includes a stepped plate-like ceiling that is D-shaped when viewed from above, and a peripheral wall that extends downward from the periphery of the ceiling.

[0025] An inlet port Pi is formed in the ceiling of the main body 11a, penetrating in the vertical direction.

[0026] 3, a support hole 11c is formed in the ceiling of the main body 11a, recessed upward from the lower end surface thereof, and a support shaft 14 is inserted and fixed into this support hole 11c.

[0027] 2, the socket 11b is cylindrical and has a bottom, and protrudes outward from the peripheral wall of the main body 11a. The drive source 40 is inserted and fixed in the socket 11b. The gap between the socket 11b and the drive source 40 is sealed with packing.

[0028] A through-hole 11d is formed in the peripheral wall of the main body 11a and in the bottom of the socket 11b, penetrating the socket 11b in the axial direction. A rod 41 (described later) is inserted through this through-hole 11d, and the tip of the rod 41 is disposed in the valve chamber 13 (see FIG. 3).

[0029] 2 and 3, a first port P1 (see FIG. 2), a second port P2 (see FIG. 3), and an outlet port Pe (see FIG. 3) are formed in the stator 12. The first port P1, the second port P2, and the outlet port Pe all pass through the stator 12 in the vertical direction.

[0030] The first port P1, the second port P2, and the outlet port Pe are formed to be located at either of the vertices of an isosceles triangle when the stator 12 is viewed from above (see FIG. 6). The distance between the first port P1 and the outlet port Pe is approximately the same as the distance between the second port P2 and the outlet port Pe.

[0031] Referring to Figure 3, the main body 11a and the stator 12 are fastened together with bolts (not shown). The stator 12 has a groove recessed downward from the upper end face along its edge. The main body 11a is pressed against a packing placed in the groove. The space between the main body 11a and the stator 12 is sealed. The main body 11a and the stator 12 form a valve chamber 13.

[0032] The stator 12 also has a groove formed along a leg 27 (described later) of the valve element 20 stopped at the first rotation position and a leg 27 of the valve element 20 stopped at the second rotation position. This groove is recessed downward from the upper end surface of the stator 12. A packing 15 is also disposed in the groove.

[0033] The valve body 20 is made of resin and is configured to have an elliptical shape in top view, consisting of a cylindrical portion 21 that is circular in top view, and a dome portion 22 that extends radially outward in a U-shape in top view from the lower end of the cylindrical portion 21. The valve body 20 may be made of metal, and the material may be changed as appropriate.

[0034] The cylindrical portion 21 is cylindrical with a stepped outer diameter, and includes a large-diameter cylindrical portion 23 , a small-diameter cylindrical portion 24 , and a rotating body 25 .

[0035] The large-diameter cylindrical portion 23 has a peripheral wall that extends axially and has a generally semicircular arc shape in a top view and a cylindrical shape in a top view, and an annular ceiling that extends from the upper end of the peripheral wall toward the inner diameter side. The peripheral wall and the dome portion 22 are connected by a diagonal boundary line 20a. The large-diameter cylindrical portion 23 and the dome portion 22 form a communication passage 26 that connects their respective internal spaces.

[0036] Furthermore, at the lower ends of the large-diameter cylindrical portion 23 and the dome portion 22, a leg portion 27 is formed that is continuous along the edges of these portions and has a circular shape and a rectangular cross section.

[0037] A cap 28 having an upside-down hat shape in cross section and a C-shaped stopper 29 are disposed at the upper end of the peripheral wall of the large-diameter cylindrical portion 23. The stopper 29 is fitted to the peripheral wall and holds the cap 28 in place, with the cap 28 disposed on the ceiling side of the large-diameter cylindrical portion 23.

[0038] An annular groove is formed in the ceiling of the large-diameter cylindrical portion 23, recessed upward from the lower end face. The cap 28 is pressed against an O-ring placed in the groove. A seal is formed between the ceiling and the cap 28. In other words, the cap 28 is one of the components that define the communication passage 26.

[0039] A recess 28a recessed downward from the upper end surface is formed in the radial center of the cap 28. A bush 16 serving as a bearing for the support shaft 14 is disposed in the recess 28a.

[0040] The small-diameter cylindrical portion 24 has a peripheral wall extending upward from the upper end surface of the radial center of the ceiling of the large-diameter cylindrical portion 23, and an annular ceiling 24a extending radially inward from the upper end of the peripheral wall. With reference to Figure 5, the lower part of the ceiling 24a abuts against the upper spring bearing 33 of the resilient means 30, and the lower part of the upper spring bearing 33 abuts against the spring 32 of the resilient means 30. In other words, the valve body 20 is placed on the resilient means 30.

[0041] Returning to Figure 3, a rotating body 25 having a smaller diameter than the small-diameter cylindrical portion 24 is formed above the small-diameter cylindrical portion 24. The rotating body 25 is formed in a cylindrical shape extending upward from the upper end surface at the radial center of the ceiling 24a of the small-diameter cylindrical portion 24. A recessed portion 25a is formed in the radial center of the rotating body 25, recessed downward from the upper end surface. A bushing 16 is disposed in the recessed portion 25a. The rotating body 25 transmits power, and its detailed configuration will be described later.

[0042] A through-hole 21a is formed in the cylindrical portion 21, penetrating it in the axial direction. The axis of this through-hole 21a substantially coincides with the axis of the cylindrical portion 21. The axis of the through-hole 21a also substantially coincides with the axis of the recess 25a in the rotating body 25 and the axis of the recess 28a in the cap 28. Furthermore, the axis of the through-hole 21a substantially coincides with the axis Ax of the outlet port Pe, which is shown by the imaginary line in FIG. 3.

[0043] The support shaft 14 is inserted through the two bushings 16 and the through hole 21 a. In other words, the support shaft 14 is disposed on the axis Ax of the outlet port Pe. The valve element 20 is movable in the axial direction along the support shaft 14 and rotatable around the support shaft 14.

[0044] A lower stopper 17 serving as a seat and an upper stopper 18 are fixed to a portion of the support shaft 14 located inside the valve body 20. The lower stopper 17 is disposed below and spaced apart from the upper stopper 18. Here, the upper stopper 18 is a stopper that restricts the extension of the spring means.

[0045] A spring means 30 is provided between the lower stopper 17 and the upper stopper 18 .

[0046] As shown in FIG. 5, the resilient means 30 is composed of a lower spring bearing 31, a spring 32, and an upper spring bearing 33 in the form of a disk.

[0047] The lower spring bearing 31 is an annular metal plate that is inserted onto the support shaft 14 and is positioned above the lower stopper 17. The lower spring bearing 31 abuts against the lower stopper 17 to prevent it from coming off downward.

[0048] The spring 32 is inserted through the support shaft 14 and is disposed above the lower spring bearing 31. In this embodiment, the elastic member is the spring 32, which is a coiled wave spring, but it may also be a coil spring, a leaf spring, or rubber, and the elastic member may be changed as appropriate. Furthermore, multiple elastic members may be disposed in the circumferential or axial direction, or two or more types of elastic members may be disposed.

[0049] The upper spring bearing 33 is a stepped cylindrical metal member, and is inserted onto the support shaft 14 and positioned above the spring 32 .

[0050] The upper spring support 33 includes a bottom portion 33a, a peripheral wall 33b, a protruding portion 33c, and a mounting portion 33d.

[0051] The bottom portion 33a is annular and has a flat plate shape. The support shaft 14 is inserted into a through hole that passes through the bottom portion 33a in the axial direction.

[0052] The peripheral wall 33b is cylindrical and extends axially upward from the upper surface of the outer diameter end of the bottom portion 33a.

[0053] An upper stopper 18 is disposed on the inner diameter side of the peripheral wall 33b. Furthermore, the upper part of the bottom portion 33a abuts against the upper stopper 18, thereby preventing the upper spring receiver 33 from coming off upward.

[0054] The protruding portion 33c has an annular flat plate shape that extends radially outward from the outer peripheral surface of the upper end of the peripheral wall 33b.

[0055] An axially compressed spring 32 is disposed between the lower end surface of the protruding portion 33 c and the upper end surface of the lower spring support 31 .

[0056] The mounting portion 33d is an annular convex portion that protrudes axially upward from the upper surface of the outer diameter end of the protruding portion 33c. The ceiling 24a of the valve body 20 is mounted on the mounting portion 33d. In other words, the valve body 20 is suspended from the support shaft 14.

[0057] The valve element 20 moves in the axial direction along the support shaft 14 in response to the pressure difference between the inside and outside of the valve element 20. In other words, the axial movement of the valve element 20 is guided by the support shaft 14.

[0058] More specifically, the greater the refrigerant pressure in the space outside the valve element 20 in the valve chamber 13 becomes compared to the refrigerant pressure inside the valve element 20, i.e., inside the communication passage 26, the greater the force moving the valve element 20 toward the stator 12. When this force exceeds the biasing force of the spring 32 in the elastic means 30, the valve element 20 moves from the state shown in Fig. 4 toward the stator 12 while compressing the spring 32, and is pressed against the packing 15 as shown in Fig. 3.

[0059] 3, when the valve element 20 is stopped in the first rotation position, the legs 27 are pressed against the packing 15 while the discharge fluid Pd is flowing into the valve chamber 13 from the inlet port Pi. As a result, the refrigerant switching valve V separates the communication passage 26 from the space outside the valve element 20 in the valve chamber 13, and communicates the inlet port Pi with the first port P1 and the second port P2 with the outlet port Pe.

[0060] On the other hand, as the flow of discharge fluid Pd into the valve chamber 13 stops and the difference between the pressure of the refrigerant outside the valve element 20 in the valve chamber 13 and the pressure of the refrigerant in the communicating passage 26 becomes smaller, the force moving the valve element 20 toward the stator 12 becomes smaller. When this force becomes smaller than the biasing force of the spring 32 in the elastic means 30, the valve element 20 moves from the state shown in Figure 3 in accordance with the expansion of the spring 32, and is released from the state of being pressed against the packing 15, i.e., floats up, as shown in Figure 4.

[0061] The floating of the valve body 20 is stopped when the bottom portion 33 a of the upper spring bearing 33 abuts against the upper stopper 18 .

[0062] In this way, by rotating the valve element 20 to the second rotation position in a floating state, it is possible to reduce the generation of a large frictional force between the valve element 20 and the packing 15. The rotation of the valve element 20 will be described below.

[0063] First, the driving source 40 and the rotating body 25 will be described.

[0064] The drive source 40 is a solenoid that, when energized, advances the rod 41 toward the valve chamber 13. The drive source 40 also has a spring (not shown), and when energization is stopped, the urging force of the spring causes the rod 41 to retract toward the drive source 40. Note that the drive source may be configured to retract the rod when energized and advance the rod by the force of the spring when de-energized.

[0065] As shown in Fig. 6, the rod 41 is a cylindrical body having a first ridge portion 42, a small-diameter shaft portion 43, and a second ridge portion 44. Fig. 6 shows the valve body 20 moved from a first rotation position indicated by a two-dot chain line to a second rotation position indicated by a solid line. For convenience of illustration, some parts, such as the packing 15, are omitted from Fig. 6.

[0066] A recess 50, a long thick portion 51, and a short thick portion 52 are formed on the outer periphery of the rotating body 25. The long thick portion 51 has a half arc shape when viewed from above, and the short thick portion 52 has a one-eighth arc shape when viewed from above.

[0067] When the valve body 20 is rotated from the first rotation position to the second rotation position, the valve body 20 is first floated as described above.

[0068] When the rod 41 advances, the first convex portion 42 comes into contact with the long thick portion 51. The long thick portion 51 is pressed by the advancing rod 41, and rotates clockwise as the advance distance of the rod 41 increases.

[0069] As the rod 41 advances further, the first convex portion 42 and the long thick portion 51 move apart, and the second convex portion 44 comes into contact with the short thick portion 52. The short thick portion 52 is pressed by the advancing rod 41 and rotates clockwise as the advancement distance of the rod 41 increases.

[0070] Furthermore, the valve element 20, which is integral with the rotating body 25, also rotates clockwise together with the rotating body 25. During this time, the ceiling 24a of the valve element 20 is in sliding contact with the mounting portion 33d of the upper spring bearing 33, but the valve element 20 remains mounted on the mounting portion 33d. This reduces the frictional force generated between the leg portion 27 at the lower end of the valve element 20 and the upper surface of the stator 12 or the packing 15. Furthermore, the valve element 20 is lightweight because it is made of resin, which also contributes to reducing the frictional force.

[0071] Furthermore, since the mounting portion 33d is disposed on the outermost diameter side of the upper spring bearing 33, a large area of ​​sliding contact with the ceiling 24a of the valve body 20 can be ensured, resulting in excellent sliding properties.

[0072] Furthermore, since the mounting portion 33d is disposed on the outer diameter side of the upper spring bearing 33, the ceiling 24a of the valve body 20 can be stably supported.

[0073] Furthermore, the lower part of the mounting portion 33d abuts against the spring 32, and the upper part abuts against the underside of the ceiling 24a, and since the mounting portion 33d and the spring 32 are arranged on the same axis, the spring force of the spring 32 can be applied in a balanced manner toward the ceiling 24a.

[0074] Thereafter, the rod 41 advances a predetermined distance, and the valve body 20 stops at the second rotation position, and is pressed against the packing 15 in the same manner as when the valve body 20 stops at the first rotation position.

[0075] The valve element 20 stopped at the second rotation position is pressed against the packing 15 in the same manner as when it is stopped at the first rotation position. As a result, the refrigerant switching valve V separates the communication passage 26 from the space outside the valve element 20 in the valve chamber 13, and communicates the inlet port Pi with the second port P2 and the first port P1 with the outlet port Pe.

[0076] When the valve body 20 is rotated from the second rotation position to the first rotation position, the valve body 20 is floated in the same manner as when the valve body 20 is stopped at the first rotation position.

[0077] When the power supply to the drive source 40 is stopped and the rod 41 is retracted by a spring (not shown), the first convex portion 42 comes into contact with the short thick portion 52 .

[0078] The shorter thicker portion 52 is pressed by the retracting rod 41 and rotates counterclockwise as the retracting distance of the rod 41 increases.

[0079] Furthermore, the valve element 20, which is integral with the rotating body 25, also rotates counterclockwise together with the rotating body 25.

[0080] Thereafter, as shown by the two-dot chain line in FIG. 6, the rod 41 moves back a predetermined distance, that is, stops at the position where it has moved back the most, and the valve body 20 stops at the first rotation position.

[0081] As described above, in the refrigerant switching valve V of this embodiment, even if the pressure acting on the valve element 20 changes and the valve element 20 attempts to move axially along the support shaft 14, contact between the elastic means 30, which expands and contracts in response to this, and the housing 10 is prevented.

[0082] That is, the refrigerant switching valve V can reduce the generation of large frictional forces between the valve element 20 and the housing 10. This allows the valve element 20 to be positioned at the first rotation position or the second rotation position with high accuracy.

[0083] In addition, the bush 16 interposed between the support shaft 14 and the valve body 20 not only allows the valve body 20 to rotate smoothly around the support shaft 14, but also allows the valve body 20 to move smoothly along the support shaft 14.

[0084] Furthermore, since the bushes 16 are arranged on both axial sides of the support shaft 14, sandwiching the spring means 30, not only can the valve body 20 rotate more smoothly around the support shaft 14, but the valve body 20 can also move more smoothly along the support shaft 14.

[0085] Furthermore, since the support shaft 14 is provided with an upper stopper 18, it is possible to restrict the extension of the resilient means 30. This makes it possible to prevent the valve element 20, which is pushed by the resilient means 30 and moves, from coming into contact with other objects such as the case 11 and the rod 41. In particular, it is possible to prevent the valve element 20 from abutting in a direction intersecting the moving direction of the rod 41, thereby preventing the movement of the rod 41 from being hindered or a large frictional force from being generated between the rod 41 and the valve element 20.

[0086] Furthermore, since the upper stopper 18 is disposed radially inward of the peripheral wall 33b of the upper spring bearing 33, it is possible to guide the axial movement of the upper spring bearing 33. This prevents the upper spring bearing 33 from tilting relative to the support shaft 14, thereby preventing the valve element 20 placed on the upper spring bearing 33 from also tilting.

[0087] The axial dimension of the peripheral wall 33b of the upper spring bearing 33 is longer than the distance that the valve element 20 moves in the axial direction, i.e., the distance that the valve element 20 moves from a state in which its floating is restricted by the upper stopper 18 to a state in which the leg 27 of the valve element 20 is pressed against the packing 15. This prevents the ceiling 24a of the valve element 20 from contacting the upper stopper 18.

[0088] The support shaft 14 penetrates from the outside to the inside of the valve element 20 and overlaps with the outlet port Pe in the axial direction. Therefore, whether the valve element 20 is stopped at the first rotation position or the second rotation position, the support shaft 14, which protrudes into the valve element 20, can function as a guide for the refrigerant flowing toward the outlet port Pe. This facilitates smooth movement of the refrigerant toward the outlet port Pe, making it difficult for the valve element 20 to shift position and allowing the valve element 20 to be held accurately at the first rotation position or the second rotation position.

[0089] A cap 28 is disposed below the support shaft 14, and its recess 28a projects toward the outlet port Pe along the axis of the outlet port Pe, thereby allowing the refrigerant to move more smoothly toward the outlet port Pe.

[0090] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0091] For example, in the above embodiment, the driving source is a solenoid, but this is not limiting and may be manual or a motor, or may be changed as appropriate.

[0092] In addition, in the above embodiment, the valve element is rotated by utilizing the axial movement of the rod, which is described as a so-called rack and pinion configuration, but this is not limited to this, and the valve element may be rotated by a motor, and the drive means for rotating the valve element may be changed as appropriate.

[0093] In addition, in the above embodiment, the refrigerant switching valve was described as a four-way valve, but this is not limited to this, and the number of ports may be changed as appropriate, or it may be an opening / closing valve that opens and closes between the inlet and outlet paths.

[0094] In the above embodiment, the valve body and the rotating body are described as being integral, but this is not limited thereto, and the valve body and the rotating body, which were separate bodies, may be assembled by bonding, recess and projection fitting, or the like.

[0095] In the above embodiment, the valve element is configured to rotate around the support shaft, but the present invention is not limited to this, and the support shaft and the valve element may be configured to rotate together. In this case, a rotating body separate from the valve element may be provided on the support shaft.

[0096] Furthermore, in the above embodiment, the spring means is described as being composed of a lower spring retainer, a spring, and an upper spring retainer, but this is not limited to this and may be a spring only, or a thrust bearing may be arranged between the valve body and the upper spring retainer, or may be modified as appropriate.

[0097] In the above embodiment, a lower stopper separate from the support shaft is fixed to the support shaft as a seat, but the present invention is not limited to this and the seat may be formed integrally with the support shaft. In other words, as long as the spring means can be disposed, the structure may be changed as appropriate.

[0098] In the above embodiment, an upper stopper separate from the support shaft is fixed to the support shaft as a stopper, but this is not limiting and the stopper may be formed integrally with the support shaft. In other words, as long as it is possible to restrict the extension of the resilient means, this may be changed as appropriate.

[0099] In addition, in the above embodiment, the gasket that seals the gap between the case and the stator in the housing is described as being located on the stator side, but this is not limited to this, and the gasket may also be located on the case side.

[0100] In the above embodiment, the packing that seals the gap between the valve disc and the stator is disposed on the stator side, but this is not limited thereto, and the packing may be disposed on the valve disc side. Even in this configuration, the packing floats together with the valve disc, and is separated from the stator or the contact area is reduced, thereby reducing the frictional force generated between the valve disc and the stator.

[0101] REFRIGERATION PATH 1 Refrigerant circuit 10 Housing 14 Support shaft 16 Bush (bearing) 17 Lower stopper (seat) 18 Upper stopper (stopper) 20 Valve body 30 Resilient means 31 Lower spring retainer 32 Spring 33 Upper spring retainer (disk) Pe Outlet port (outlet path) Pi Inlet port (inlet path) V Refrigerant switching valve (switching valve)

Claims

1. A changeover valve comprising a housing having an inlet passage and an outlet passage, and a valve body rotatably provided within the housing for switching between the inlet passage and the outlet passage, in which the pressure acting on the valve body changes, wherein the valve body is rotatably guided relative to a support shaft provided within the housing, and a resilient means is disposed between the valve body and a seat portion of the support shaft.

2. A switching valve as set forth in claim 1, wherein said support shaft is fixed to said housing, and a bearing is interposed between said support shaft and said valve body.

3. A switching valve according to claim 2, wherein the bearings are disposed on both axial sides of the support shaft with the resilient means interposed therebetween.

4. A switching valve as set forth in claim 1, wherein said support shaft is provided with a stopper for restricting the extension of said elastic means.

5. A changeover valve as set forth in any one of claims 1 to 4, wherein said resilient means comprises a spring and a disk in sliding contact with said valve body.

6. A switching valve as set forth in claim 1, wherein said support shaft is disposed penetrating from the exterior to the interior of said valve body and overlaps with said outflow passage in the axial direction of said support shaft.

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