Switching valve

Abstract

To provide a switching valve that enables a valve body to rotate smoothly.　The switching valve comprises: a biasing member 31 that biases a valve body 20 in a direction away from a valve seat 15; a retainer 32 positioned between the biasing member 31 and the valve body 20; and a regulating part 33 that regulates the movement of the retainer 32.

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 valve box, a valve element, a lower cam, an upper cam, a spring, and a disc spring. Four valve holes are formed in the bottom surface of the valve box, and connecting pipes are connected to each valve hole. The valve element is arranged rotatably and vertically movable within the valve box. A lower cam having a vertically uneven shape is formed on the upper surface of the valve element. An upper cam is arranged above the lower cam. The uneven portions of the lower cam and the lower cam are arranged opposite each other vertically. The spring is housed in a recess provided in the bottom surface of the valve box and biases the valve element in a direction away from the valve seat surface on the bottom surface of the valve box, i.e., upward. The disc spring is arranged between the upper cam and the top surface of the valve box and biases the upper cam downward.

[0004] When the refrigerant circuit is in operation, the protrusion of the lower cam rides on the protrusion of the upper cam, i.e., the disc spring is compressed, causing the upper cam to move upward, and the spring is compressed, causing the valve disc to move downward, with the underside of the valve disc tightly contacting the valve seat. This separates the flow path that connects two of the four valve holes from the flow path that connects the other two valve holes.

[0005] Furthermore, when switching the operating state of the refrigerant circuit, i.e., when changing the combination of valve holes, the upper cam is rotated by a motor. When the upper cam is rotated, the biasing forces of the spring and the disc spring bring the upper and lower cams closer together, and the concave and convex portions of the concave and convex cams fit together vertically. This almost completely eliminates the biasing force of the disc spring, and the biasing force of the spring prevails, separating the lower surface of the valve disc from the valve seat surface. In this state, if the upper cam is rotated further, the valve disc will rotate together with the upper cam. This prevents large frictional forces from occurring between the valve disc and the valve seat surface when the valve disc rotates.

[0006] Japanese Patent Application Laid-Open No. 11-44369 (page 4, Figure 1)

[0007] In the switching valve of Patent Document 1, when the valve body rotates, it is possible to prevent large frictional forces from occurring between the valve body and the valve seat surface, but the valve body abuts against the spring while being subjected to a biasing force, and when the valve body rotates, the spring tilts, generating resistance such as sticking between the valve body and the spring, which could hinder smooth rotation.

[0008] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a switching valve in which the valve element rotates smoothly.

[0009] In order to solve the above problems, the present invention provides a switching valve comprising: a housing; and a valve element rotatably provided within the housing, wherein the housing is formed with an inlet port for introducing fluid into the housing, an outlet port for discharging fluid from the housing, and a plurality of other ports for introducing fluid into or discharging fluid from the housing, wherein the combination of the inlet port and the plurality of other ports and the outlet port and the plurality of other ports can be changed by rotating the valve element while it is moved within the housing in a state away from a valve seat, the switching valve further comprising: a biasing member that biases the valve element in a direction away from the valve seat, a retainer disposed between the biasing member and the valve element, and a restricting portion that restricts movement of the retainer. According to this, the restricting portion restricts movement of the retainer and stabilizes the attitude of the biasing member, thereby preventing tilting of the biasing member when the valve element rotates, thereby smoothing the rotation of the valve element.

[0010] The valve body side end surface of the retainer may be flat, which allows the valve body to rotate smoothly along the valve body side end surface of the retainer.

[0011] The restricting portion may be annular, which makes it possible to stabilize the position of the retainer.

[0012] The valve disc may be provided rotatably and axially movable relative to a support shaft provided in the valve chamber, and the retainer may be provided in a position in the housing overlapping with the support shaft in the axial direction. In this way, the valve disc can be separated from the valve seat by a single retainer, biasing member, and restriction portion, regardless of the rotational position of the valve disc.

[0013] The housing may have a recess, and the biasing member, the retainer, and the restricting portion may be disposed in the recess, which simplifies assembly of the switching valve.

[0014] The recess may be a port provided in the housing, whereby the biasing member, the retainer, and the restricting portion can be disposed using the port.

[0015] The recess may be formed with a step that abuts against the retainer when the retainer is in the retracted position. With this, the retainer is sandwiched between the valve body and the step when the valve body is seated, so the position of the retainer is stable and the sealing performance of the valve body is not affected.

[0016] The restricting portion may be a stopper member fixed to the housing. In this case, the movement of the retainer toward the valve body can be restricted by the stopper member that is a separate member from the housing, which simplifies assembly.

[0017] The stopper member may be provided with a rotation restricting portion that interferes with the valve body and restricts the rotation range thereof, whereby the valve body can be positioned at a desired rotational position with high accuracy by the rotation restricting portion.

[0018] 4 is a schematic diagram showing a refrigerant circuit to which a switching valve of a first embodiment according to the present invention is applied; FIG. 5 is a perspective view of the switching valve of the first embodiment; FIG. 6 is a cross-sectional view taken along line A-A of FIG. 2 in a state in which the gap between the valve body and the housing is sealed in the first embodiment; FIG. 7 is a cross-sectional view taken along line A-A of FIG. 2 in a state in which the valve body is raised in the first embodiment; FIG. 8 is an enlarged view of a portion of FIG. 4; FIG. 9 is a top view showing the valve body rotated from a first rotation position to a second rotation position in the first embodiment; FIG. 10 is an enlarged cross-sectional view of a main part of a switching valve of a second embodiment according to the present invention (see the A-A cut position in FIG. 2 ); FIG. 11(a) is a schematic diagram showing the valve body in the first rotation position in the second embodiment; and FIG. 11(b) is a schematic diagram showing a modified example of the first embodiment.

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0020] A switching valve according to a first embodiment will be described with reference to FIGS. 1 to 6. In the following description, the top and bottom of FIG. 3 will be taken as the top and bottom of the switching valve.

[0021] 1, a switching valve V of the present invention is a four-way valve provided in a refrigerant circuit 1. In addition to the 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.

[0022] The switching valve V is provided with an inlet port Pi as an inlet passage connected to the discharge side of the compressor C through a discharge passage 2, a first port P1 connected to a first load L1 through a first passage 3, a second port P2 connected to a second load L2 through a second passage 4, and an outlet port Pe as an outlet passage connected to the suction side of the compressor C through an outlet passage 5. The first load L1 and the second load L2 are connected through a third passage 6.

[0023] The switching valve V switches between passing the discharge fluid Pd from the compressor C through the first load L1 and then the second load L2 as shown by the solid line, and passing the discharge fluid Pd through the second load L2 and then the first load L1 as shown by the dashed line. The switching valve V will be described in detail below.

[0024] 2 and 3, the 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).

[0025] The housing 10 is mainly composed of a case 11 and a stator 12 .

[0026] 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.

[0027] 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.

[0028] An inlet port Pi is formed in the ceiling of the main body 11a, penetrating in the vertical direction.

[0029] A support hole 11c (see FIG. 3) is formed in the ceiling of the main body 11a, recessed upward from the lower end surface thereof. A support shaft 14 is inserted and fixed into this support hole 11c.

[0030] 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 into and fixed in the socket 11b. The space between the socket 11b and the drive source 40 is sealed with packing.

[0031] 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 positioned in the valve chamber 13.

[0032] 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.

[0033] The first port P1, the second port P2, and the outlet port Pe are formed to be located at 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 substantially the same as the distance between the second port P2 and the outlet port Pe.

[0034] 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 12c formed along its edge, recessed downward from the upper end surface. The main body 11a is pressed against a packing 18 disposed in the groove 12c. A seal is formed between the main body 11a and the stator 12. The main body 11a and the stator 12 form a valve chamber 13.

[0035] The stator 12 also has a groove 12d 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. The groove 12d is recessed downward from the upper end surface of the stator 12. A packing 15 serving as a valve seat is disposed in the groove 12d.

[0036] The valve body 20 is made of resin and has a cylindrical portion 21 that is circular in top view and a dome portion 22 that is elliptical in top view. The valve body 20 may be made of metal, and the material may be changed as appropriate.

[0037] The cylindrical portion 21 has a bottomed cylindrical shape and extends in the vertical direction. A bush 16 is disposed on the inner diameter side of the cylindrical portion 21, and the support shaft 14 is inserted into the bush 16.

[0038] The dome portion 22 is provided below and connected to the cylindrical portion 21. A passage 26 is formed inside the dome portion 22. More specifically, the passage 26 is defined by the inner surface of the dome portion 22 and the upper surface of the stator 12. An annular leg portion 27 is formed at the lower end of the dome portion 22, continuing along the edges of these and extending radially.

[0039] 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 is rotatable around the support shaft 14.

[0040] 3 to 5, a stepped recess 17 is formed as a recess above the outlet port Pe of the stator 12. The stepped recess 17 has a small diameter portion 17a and a large diameter portion 17b provided on the upper edge of the small diameter portion 17a.

[0041] A resilient means 30 is disposed in the stepped recess 17. The resilient means 30 is mainly composed of a spring 31 as a biasing means, a retainer 32, and a stopper member 33 as a restricting portion.

[0042] The spring 31 is a coiled wave spring, and is housed in the stepped recess 17 while being placed on the bottom 17c that constitutes the small diameter portion 17a. In other words, the bottom 17c functions as a lower spring support for the spring 31. The spring 31 may be a coil spring, a leaf spring, or an elastic body such as rubber, and may be modified as appropriate.

[0043] The retainer 32 is a cylindrical body made of resin. The retainer 32 is composed of a cylindrical portion 32a extending vertically and an annular flange portion 32b extending radially outward from the lower edge of the cylindrical portion 32a. The retainer 32 may be made of metal, or the material may be changed as appropriate.

[0044] The retainer 32 is interposed between the spring 31 and the valve body 20. More specifically, the upper end surface 32c of the retainer 32 is flat and abuts on the inner diameter side of the contact portion between the lower surface of the leg portion 27 of the valve body 20 and the packing 15. The upper end surface 32c of the retainer 32 is approximately parallel to the lower surface of the leg portion 27 of the valve body 20.

[0045] The stopper member 33 is a plate-shaped ring member made of resin, and is press-fitted and fixed into the large diameter portion 17b of the stepped recess 17. The inner diameter of the stopper member 33 is smaller than the small diameter portion 17a, and the stopper member 33 protrudes further inward than the side wall portion that constitutes the small diameter portion 17a. The stopper member 33 may be made of metal, and the material may be changed as appropriate.

[0046] The cylindrical portion 32a of the retainer 32 is loosely inserted into the stopper member 33 so as to be movable up and down. The flange portion 32b of the retainer 32 is formed with a diameter larger than the inner diameter of the stopper member 33 and is disposed below the stopper member 33. The retainer 32 is biased upward by the spring 31, and the flange portion 32b comes into contact with the lower surface of the stopper member 33, thereby restricting the upward movement of the retainer 32.

[0047] 3, the valve element 20, which is stopped at the first rotation position, is pushed down by the pressure of the discharge fluid Pd flowing into the valve chamber 13 from the inlet port Pi, and the leg 27 is pressed against the packing 15. At this time, the retainer 32 is positioned at a retracted position where it retracts against the biasing force of the spring 31 until its upper end surface 32c is substantially flush with the upper surface of the stator 12.

[0048] As a result, the switching valve V separates the passage 26 from the space outside the valve body 20 in the valve chamber 13, connecting the inlet port Pi to the first port P1 and connecting the second port P2 to the outlet port Pe.

[0049] 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 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 31 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 31, and separates from the packing 15, i.e., floats up, as shown in Figure 4.

[0050] The floating of the valve body 20 is stopped when the flange portion 32b of the retainer 32 abuts against the underside of the stopper member 33. When the flange portion 32b of the retainer 32 abuts against the underside of the stopper member 33, the spring 31 is slightly compressed, and therefore the retainer 32 is suppressed from vibrating when sandwiched between the stopper member 33 and the spring 31. At this time, the bottom surface 21a of the cylindrical portion 21 and the bottom surface 14a of the support shaft 14 are slightly spaced apart vertically.

[0051] 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.

[0052] The valve element 20 may rise upward due to the biasing force of the spring 31, vibration, or the like. In this case, the bottom surface 21a of the cylindrical portion 21 abuts against the bottom surface 14a of the support shaft 14, preventing the valve element 20 from rising any further. The position where the bottom surface 21a of the cylindrical portion 21 abuts against the bottom surface 14a of the support shaft 14 is called the upper limit movable position of the valve element 20. When the valve element 20 is in the upper limit movable position, the valve element 20 does not come into contact with the rod 41 of the drive source 40. This prevents deformation of the rod 41 and the generation of wear debris due to contact between the valve element 20 and the rod 41, and prevents malfunction of the rod 41.

[0053] First, the driving source 40 and the cylindrical portion 21 of the valve body 20 will be described.

[0054] 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.

[0055] 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 illustrates a state in which the valve body 20 has been moved from a first rotation position indicated by a two-dot chain line to a second rotation position indicated by a solid line.

[0056] A recess 50, a long thick portion 51, and a short thick portion 52 are formed on the outer periphery of the cylindrical portion 21. 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] Furthermore, the valve element 20, which is integral with the cylindrical portion 21, also rotates clockwise integrally with the cylindrical portion 21. During this time, the legs 27 of the valve element 20 slide along the upper end surface 32c of the retainer 32, but when the valve element 20 is in a raised state, the flange portion 32b of the retainer 32 abuts against the stopper member 33, restricting the upward movement of the retainer 32, and the valve element 20 is placed on the upper end surface 32c of the retainer 32. As a result, the biasing force of the spring 31 does not act excessively on the valve element 20, and the frictional force between the valve element 20 and the retainer 32 is reduced.

[0061] Furthermore, when the upward movement of the retainer 32 is restricted, the biasing force of the spring 31 acts on the stopper member 33, so that the biasing force of the spring 31 is substantially not applied to the valve body 20. In other words, when the retainer 32 abuts against the stopper member 33, the biasing force of the spring 31 does not act on the valve body 20 even if the spring 31 is not designed to have its natural length. Furthermore, because the bottom inside the cylindrical portion 21 does not abut against the lower surface of the support shaft 14, the generation of frictional force between the cylindrical portion 21 and the support shaft 14 can be suppressed.

[0062] Furthermore, when the retainer 32 comes into contact with the stopper member 33, the retainer 32 is sandwiched between the stopper member 33 and the spring 31 from above and below, so that the retainer 32 is locked and the position of the retainer 32 is stabilized. As a result, even if the valve body 20 slides along the upper end surface 32c of the retainer 32, it is possible to prevent the retainer 32 from tilting and generate a large resistance force, thereby enabling the valve body 20 to rotate smoothly.

[0063] Furthermore, since the upper end surface 32c of the retainer 32 is a flat surface, the valve body 20 can rotate smoothly along the upper end surface 32c.

[0064] Furthermore, the upper surface of the flange portion 32b of the retainer 32 and the lower surface of the stopper member 33 are annular flat surfaces and are arranged substantially parallel to each other, so that they come into surface contact in the circumferential direction, preventing the retainer 32 and the spring 31 from tilting relative to the stopper member 33. This effectively prevents the retainer 32 and the spring 31 from generating resistance to the rotation of the valve body 20.

[0065] Thereafter, the rod 41 advances a predetermined distance, and the valve element 20 stops at the second rotation position. Thereafter, the inflow of the discharge fluid Pd presses the valve element 20 against the packing 15 in the same manner as when the valve element 20 stops at the first rotation position.

[0066] 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 switching valve V separates the 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.

[0067] 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.

[0068] 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 .

[0069] The shorter thicker portion 52 is pressed by the retracting rod 41 and rotates counterclockwise as the retracting distance of the rod 41 increases.

[0070] Furthermore, the valve element 20, which is integral with the cylindrical portion 21, also rotates counterclockwise together with the cylindrical portion 21.

[0071] 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.

[0072] As described above, when the valve body 20 of the switching valve V of this embodiment rises, the spring 31 and the retainer 32 expand and contract accordingly and come into contact with the stopper member 33, thereby stabilizing the posture.

[0073] That is, the switching valve V can reduce the generation of resistance force on the valve element 20 caused by the inclination of the spring 31 and the retainer 32. This allows the valve element 20 to be positioned at the first rotation position or the second rotation position with high accuracy.

[0074] Furthermore, since the retainer 32 is positioned so as to overlap the support shaft 14 of the valve body 20 in the axial direction, i.e., on the axis Ax, the valve body 20 can be lifted from the packing 15 by a single elastic means 30 regardless of the rotational position of the valve body 20.

[0075] Furthermore, because the resilient means 30 is disposed in the stepped recess 17 provided in the stator 12, the assembly work of the switching valve V is simplified compared to a configuration in which the resilient means is incorporated between the valve element 20 and the support shaft 14. Furthermore, when the resilient means is incorporated between the valve element 20 and the support shaft 14, a seal is required between the support shaft 14 and the valve element 20, and a seal is required between the valve element 20 and the stator 12, but the switching valve V of this embodiment requires only one packing 15, thereby reducing fluid leakage between the valve chamber 13 and the passage 26.

[0076] Furthermore, since there is no need to provide separate recesses in the stator 12 for accommodating the spring 31, the retainer 32, and the stopper member 33, there is no risk of the structural strength of the stator 12 being reduced.

[0077] Furthermore, the stepped recess 17 is provided in the outflow port Pe, and the outflow port Pe can be used to arrange the resilient means 30, so the structure of the stator 12 can be simplified.

[0078] The stopper member 33 is press-fitted and fixed into the large diameter portion 17b of the stepped recess 17. This allows the stopper member 33, which is a separate member from the stator 12, to be press-fitted and fixed into the large diameter portion 17b to form a restricting portion that restricts movement of the retainer 32, making the assembly of the switching valve V easy.

[0079] Furthermore, since the upper surface of the stopper member 33 is formed to be approximately flush with the upper surface of the stator 12, no radial gap is formed between the valve body 20 and the stopper member 33, and the flow of fluid is not obstructed by this gap.

[0080] Next, a switching valve according to a second embodiment will be described with reference to Figures 7 and 8. Note that the description of the same configuration as in the first embodiment will be omitted.

[0081] 7(a) and 7(b), the switching valve V2 of the second embodiment has an annular stepped recess 217 formed to surround the outlet port Pe of the stator 212. The stepped recess 217 opens upward. The stepped recess 217 has a small diameter portion 217a and a large diameter portion 217b provided on the upper edge of the small diameter portion 217a.

[0082] A spring 231 is disposed in the stepped recess 217. A ring-shaped retainer 232 is fixed to the upper end of the spring 231. The retainer 232 is disposed in the large diameter portion 217b of the stepped recess 217.

[0083] The stopper member 233 includes a small diameter portion 233a, a flange portion 233b, and a step portion 233c. The small diameter portion 233a is press-fitted and fixed from above into the inner circumferential surface that defines the outflow port Pe.

[0084] The flange portion 233b projects outward in an annular shape from the upper edge of the small diameter portion 233a. The flange portion 233b is disposed above the stepped recess 217. The outer diameter of the flange portion 233b is smaller than the outer diameter of the retainer 232. A portion of the flange portion 233b on the outer diameter side can abut against the leg portion 227 of the valve body 220. In the second embodiment, the leg portion 227 is formed with an annular groove that opens downward, and the packing 215 is press-fitted and fixed into the groove.

[0085] The step portion 233c is formed in an annular shape between the small diameter portion 233a and the flange portion 233b. The outer diameter of the step portion 233c is smaller than the inner diameter of the retainer 232. That is, the outer peripheral surface of the small diameter portion 233a, the lower surface of the step portion 233c, the outer peripheral surface of the step portion 233c, and the lower surface of the flange portion 233b form a stepped cross section that expands in diameter toward the outer diameter side.

[0086] The step portion 233c abuts against the upper surface of the stator 212, and a space 218 is formed between the flange portion 233b and the upper surface of the stator 212 in which the retainer 232 can be disposed.

[0087] 7A, when the pressure in the valve chamber 213 is relatively higher than the biasing force of the spring 231, the retainer 232 is pushed down by the valve element 220 to the retracted position, and the packing 215 attached to the leg 227 of the valve element 220 is pressed against the upper surface of the stator 212. In this state, the retainer 232 is sandwiched vertically between the valve element 220 and the step 217c that forms the bottom of the large diameter portion 217b. This stabilizes the position of the retainer 232, preventing the retainer 232 from affecting the sealing performance of the valve element 220.

[0088] 7B, when the pressure in the valve chamber 213 is relatively lower than the biasing force of the spring 231, the retainer 232 rises and lifts the valve disc 220, causing the packing 215 attached to the leg 227 of the valve disc 220 to separate from the upper surface of the stator 212. In this state, the retainer 232 abuts against the lower surface of the flange 233b of the stopper member 233, thereby restricting the lift of the retainer 232. This prevents the biasing force of the spring 231 from acting excessively on the valve disc 220. In other words, when the retainer 232 abuts against the stopper member 233, the biasing force of the spring 231 does not act on the valve disc 220 even if the spring 231 is not designed to have its natural length.

[0089] As shown in FIGS. 8A and 8B, the stopper member 233 is formed with protruding pieces 233A and 233B as rotation restricting portions.

[0090] The protruding pieces 233A and 233B are each generally triangular in top view, and have sides 233Aa and 233Ba that extend tangentially to the outer circumferential surface of the stopper member 233.

[0091] As shown in FIG. 8A, when the valve body 220 is in the first rotation position, the inner surface 220a of the valve body 220 abuts against the side 233Aa of the protruding piece 233A.

[0092] As shown in FIG. 8B, when the valve body 220 is in the second rotation position, the inner surface 220b of the valve body 220 abuts against the side 233Ba of the protruding piece 233B.

[0093] In other words, when the valve body 220 rotates toward the first rotation position or the second rotation position, it abuts against the edge 233Aa of the protrusion 233A or the edge 233Ba of the protrusion 233B, and further rotation is restricted, so that the valve body 220 can be accurately positioned at the desired rotation position.

[0094] Furthermore, the stepped recess 217 in which the spring 231 is installed is provided separately from the outlet port Pe in which the stopper member 233 is installed, so that the spring 231 is less likely to affect the fluid flowing through the outlet port Pe.

[0095] Next, a modified example of the rotation restricting portion will be described with reference to FIG.

[0096] As shown in Fig. 9, a pin 12A serving as a rotation restricting portion is provided to protrude upward from the stator 12. As shown in Fig. 9(a), when the valve body 20 is located at the first rotation position, an inner surface 20a of the valve body 20 abuts against the pin 12A, and as shown in Fig. 9(b), when the valve body 20 is located at the second rotation position, an inner surface 20b of the valve body 20 abuts against the pin 12A.

[0097] In this way, the valve element 20 can be accurately positioned at the desired rotational position with a simple configuration. In this modified example, the pin 12A is applied to the configuration of the first embodiment, but the pin 12A may be applied instead of the protrusions 233A and 233B of the second embodiment.

[0098] 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.

[0099] For example, in the first and second embodiments, the valve body-side end face of the retainer is flat, but it may have an uneven shape in the circumferential direction, which can reduce the frictional force generated between the valve body and the valve body-side end face of the retainer.

[0100] In addition, in the first and second embodiments, the restricting portion is formed in an annular shape, but this is not limiting. At least one restricting portion may be provided in the circumferential direction, but from the viewpoint of the stability of the retainer, it is preferable that multiple restricting portions are provided in the circumferential direction or that the restricting portion is formed in an annular shape.

[0101] Furthermore, in the above-described first and second embodiments, a form in which the biasing means is slightly compressed when the retainer abuts against the regulating portion is exemplified, but this is not limited to this, and the biasing means may be in a state in which it is approximately at its natural length when the retainer abuts against the regulating portion.

[0102] Furthermore, in the first and second embodiments, the valve element rotates between the first and second rotation positions. However, the valve element may have three or more rotation positions.

[0103] Furthermore, in the above-described first and second embodiments, a form in which the spring means equipped with a retainer is arranged at a position overlapping with the support shaft in the axial direction is exemplified, but this is not limited to this, and the spring means may be arranged at a position where it can come into contact with the valve body at each rotation position, i.e., at multiple locations around the housing.

[0104] Furthermore, in the first and second embodiments, the restricting portion is a stopper member that is separate from the stator, but the restricting portion may be formed integrally with the stator.

[0105] Furthermore, in the first and second embodiments, the driving source is a solenoid, but this is not limiting and the driving source may be manual or a motor, or may be changed as appropriate.

[0106] In addition, in the above-described first and second embodiments, a so-called rack and pinion mechanism is configured in which the valve body is rotated by utilizing the axial movement of the rod, but this is not limited to this, and the valve body may be rotated by a motor, and the drive means for rotating the valve body may be changed as appropriate.

[0107] In addition, in the first and second embodiments, the switching valve is described as a four-way valve, but this is not limited to this, and the number of ports may be changed as appropriate, or the switching valve may be an on-off valve that opens and closes between the inlet and outlet paths.

[0108] In addition, in the first embodiment, the packing that seals the gap between the valve disc and the stator is described as being disposed on the stator side, but this is not limited thereto, and the packing may be disposed on the valve disc side. Even with 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. In this case, the portion of the stator with which the packing contacts functions as the valve seat. In other words, the member on the stator side that contacts the member on the valve disc side functions as the valve seat.

[0109] In addition, in the second embodiment, the packing is described as being disposed on the valve disc side, but the packing may be disposed on the stator side. Even in this configuration, the frictional force generated between the valve disc and the stator can be reduced by separating the packing from the valve disc or reducing the contact area. In this case, the packing functions as the valve seat. In other words, the member on the stator side that comes into contact with the member on the valve disc side functions as the valve seat.

[0110] REFRIGERATION POINTS 1 Refrigerant circuit 10 Housing 12 Stator 13 Valve chamber 14 Support shaft 15 Packing (valve seat) 17 Stepped recess (recess) 20 Valve body 26 Passage 27 Leg 30 Resilient means 31 Spring (biasing means) 32 Retainer 32b Flange 32c Upper end surface 33 Stopper member (restriction portion) 217c Step 233A Projection (rotation restriction portion) 233B Projection (rotation restriction portion) V Switching valve

Claims

1. A switching valve comprising a housing and a valve element rotatably mounted within the housing, wherein the housing is formed with an inlet port for introducing fluid into the housing, an outlet port for discharging fluid from the housing, and a plurality of other ports for discharging fluid into or from the housing, and wherein the combination of the inlet port and the plurality of other ports and the outlet port and the plurality of other ports can be changed by rotating the valve element while it is moved within the housing in a direction away from a valve seat, the switching valve comprising: a biasing member that biases the valve element in a direction away from the valve seat; a retainer that is positioned between the biasing member and the valve element; and a restricting portion that restricts movement of the retainer.

2. A switching valve according to claim 1, wherein the end surface of the retainer on the valve body side is flat.

3. A switching valve according to claim 1, wherein the restricting portion is annular.

4. A switching valve as described in claim 1, wherein the valve element is rotatable and axially movable relative to a support shaft provided within the valve chamber, and the retainer is provided in a position in the housing where it overlaps with the support shaft in the axial direction.

5. A switching valve according to claim 1, wherein a recess is provided in the housing, and the biasing member, the retainer, and the restricting portion are disposed in the recess.

6. A switching valve according to claim 5, wherein the recess is a port provided in the housing.

7. A switching valve according to claim 5 or 6, wherein the recess is formed with a step that abuts against the retainer when the retainer is in the retracted position.

8. A switching valve according to claim 1, wherein the restricting portion is a stopper member fixed to the housing.

9. A switching valve according to claim 8, wherein the stopper member is provided with a rotation restricting portion that interferes with the valve body and restricts the range of rotation.

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