Flow passage switching device

Abstract

In this flow passage switching device, an elastic member is provided in an internal space provided between a first driving member and a second driving member, the elastic member separating the first driving member and the second driving member from each other and biasing the first driving member and the second driving member in the direction toward a housing. At least one of the first driving member and the second driving member is provided with a through-hole that allows a communication passage of the first driving member or the second driving member to communicate with the internal space.

Description

Flow path switching device

[0001] The present disclosure relates to a flow path switching device configured to switch a flow path of a fluid.

[0002] Patent Document 1 discloses a flow path switching valve having a stator and a rotor seal connected to a rotor (drive member) that rotates while sliding circumferentially relative to the stator, and the rotor is supported by a spring or the like.

[0003] Japanese Patent Application Laid-Open No. 2020-144027

[0004] In the flow path switching valve disclosed in Patent Document 1, when the pressure of the fluid in the rotor seal flow path becomes greater than the elastic force of the spring supporting the rotor and the rotor is pushed down, the fluid in the rotor seal flow path leaks from the rotor seal and flows into the space below the rotor, increasing the pressure in the space below the rotor. This causes the rotor seal to be compressed by the stator due to the pressure difference between the rotor seal flow path and the space below the rotor, increasing the rotor sliding torque (i.e., the torque generated when the rotor seal slides against the stator as the rotor rotates). This can make it difficult for the rotor to rotate (drive), and the flow path switching valve disclosed in Patent Document 1 may be unable to selectively switch between multiple flow paths.

[0005] Therefore, the present disclosure has been made to solve the above-mentioned problems, and aims to provide a flow path switching device that can reliably drive a drive member and selectively switch between multiple flow paths regardless of the magnitude of the fluid pressure in the connecting passage of the drive member.

[0006] In one aspect of the present disclosure, which has been made to solve the above-mentioned problems, the flow path switching device includes a housing and a valve body portion arranged inside the housing, the valve body portion including a first drive member and a second drive member arranged adjacent to each other, the housing and at least one of the first drive member and the second drive member each including a plurality of communication passages, a sealing member for preventing fluid leakage is provided between the housing and around the communication passages in at least one of the first drive member and the second drive member, and by driving the first drive member and the second drive member, the communication passages in at least one of the first drive member and the second drive member and the communication passages in the housing are combined and connected to selectively switch between and form a plurality of flow paths, characterized in that an elastic member is provided in an internal space provided between the first drive member and the second drive member to separate the first drive member and the second drive member from each other and to urge the first drive member and the second drive member in a direction toward the housing, and a through hole is provided in at least one of the first drive member and the second drive member to communicate the communication passages with the internal space.

[0007] According to this aspect, the increased pressure in the internal space can be released to the communication passage of the drive member through the through hole. This allows the pressure in the internal space to be lowered, thereby reducing the pressure difference between the communication passage of the drive member and the internal space. This reduces the sliding torque of the drive member (i.e., the torque generated when the seal member slides on the housing when the drive member is driven), making it easier to drive the drive member. Therefore, regardless of the magnitude of the fluid pressure in the communication passage of the drive member, the drive member can be reliably driven to selectively switch between multiple flow paths.

[0008] In the above aspect, it is preferable that a plate for opening and sealing the through hole is provided in the internal space.

[0009] According to this aspect, the plate can open or seal the through hole depending on the situation. Therefore, when it is desired to reduce the pressure in the internal space, the plate can open the through hole, allowing the pressure in the internal space to escape to the communication passage of the drive member via the through hole. On the other hand, when it is desired to maintain the pressure in the internal space, the plate can seal the through hole, allowing the pressure in the internal space to be maintained.

[0010] In the above aspect, it is preferable that the valve body portion includes a rotating shaft that rotates the first drive member and the second drive member, and the plate rotates in conjunction with the rotation of the rotating shaft, and when the flow path is switched, the rotating shaft rotates in a first direction and the plate opens the through hole, and then, after the switching of the flow path is completed, the rotating shaft rotates in a second direction opposite to the first direction and the plate seals the through hole.

[0011] According to this aspect, when switching the flow paths, the pressure in the internal space can be lowered, reducing the sliding torque of the first drive member and the second drive member, facilitating driving of the first drive member and the second drive member. Therefore, regardless of the magnitude of the fluid pressure in the communication passage of the first drive member and the communication passage of the second drive member, the first drive member and the second drive member can be reliably driven and multiple flow paths can be selectively switched.

[0012] Furthermore, by maintaining the pressure in the internal space after the switching of the flow path is completed, the sealing performance of the elastic member can be ensured.

[0013] In the above aspect, it is preferable that the plate comprises a first plate member and a second plate member attached to the first plate member and sealing the through hole, and that the second plate member seals the through hole while being able to move relative to the first plate member so as to open and close the through hole.

[0014] According to this aspect, when the through holes are sealed with the plates, the second plate member can move relative to the first plate member. Therefore, even if there is variation in the flatness of the surfaces around the through holes of the first drive member and the second drive member, the second plate member can move and come into close contact with the surfaces around the through holes of the first drive member and the second drive member. This improves the sealing performance (i.e., sealing ability) of the plates sealing the through holes of the first drive member and the second drive member.

[0015] According to the flow path switching device of the present disclosure, the drive member can be reliably driven to selectively switch between a plurality of flow paths regardless of the magnitude of the pressure of the fluid in the communication path of the drive member.

[0016] 10 is a perspective view showing a flow path switching device according to the present embodiment; a front view showing a flow path switching device according to the present embodiment; a plan view showing a flow path switching device according to the present embodiment; a bottom view showing a flow path switching device according to the present embodiment; an exploded perspective view showing a flow path switching device according to the present embodiment; a cross-sectional view taken along line A-A in FIG. 2 showing a flow path switching device according to the present embodiment; a cross-sectional view taken along line B-B in FIG. 3 showing a flow path switching device according to the present embodiment; a perspective view showing the inside of an upper housing according to the present embodiment; a perspective view showing a first rotating disk according to the present embodiment; a plan view showing the first rotating disk according to the present embodiment; a bottom view showing the first rotating disk according to the present embodiment; a perspective view showing the first rotating disk cut along line CC in FIG. 10; a perspective view showing a second rotating disk according to the present embodiment; a plan view showing the second rotating disk according to the present embodiment; a bottom view showing the second rotating disk according to the present embodiment. 14 , a perspective view showing the second rotating disk cut along line D-D in FIG. 14 according to the present embodiment. A perspective view showing the rotation shaft according to the present embodiment. A cross-sectional view taken along line E-E in FIG. 17 , showing the rotation shaft according to the present embodiment. A cross-sectional view taken along line F-F in FIG. 2 , showing the flow path switching device 1 according to the present embodiment. A schematic cross-sectional view taken along line G-G in FIG. 2 , showing the rotation position of the first rotating disk relative to the upper housing for the "first pattern" of the flow path switching pattern according to the present embodiment. A schematic cross-sectional view taken along line H-H in FIG. 2 , showing the rotation position of the second rotating disk relative to the lower housing for the "first pattern" of the flow path switching pattern according to the present embodiment. A schematic view equivalent to FIG. 20 , showing the rotation position of the first rotating disk relative to the upper housing for the "second pattern" of the flow path switching pattern according to the present embodiment. A schematic view equivalent to FIG. 21 , showing the rotation position of the second rotating disk relative to the lower housing for the "second pattern" of the present embodiment. 20 showing the rotational position of the first rotating disk relative to the upper housing for the "third pattern" of the flow path switching pattern according to the present embodiment. 21 showing the rotational position of the second rotating disk relative to the lower housing for the "third pattern" according to the present embodiment. 22 a perspective view of the first rotating disk, first plate, rotating shaft, upper housing, and peripheral components (showing the first plate removed from the rotating shaft). 23 a perspective view of the second rotating disk, second plate, rotating shaft, lower housing, and peripheral components (showing the second plate removed from the rotating shaft).19 is a perspective view of a rotating shaft, a first plate, and a second plate. A cross-sectional view similar to FIG. 19 , showing the first through-hole being sealed by the first plate. A cross-sectional view similar to FIG. 29 , showing the first through-hole being opened by the first plate rotating before the first rotating disk when the rotating shaft rotates clockwise. A cross-sectional view similar to FIG. 29 , showing the first through-hole being opened by the first plate rotating before the first rotating disk when the rotating shaft rotates counterclockwise. A cross-sectional view taken along line II of FIG. 2 , showing the second through-hole being sealed by the second plate. A cross-sectional view similar to FIG. 32 , showing the second through-hole being opened by the second plate rotating before the second rotating disk when the rotating shaft rotates clockwise. A cross-sectional view similar to FIG. 32 , showing the second through-hole being opened by the second plate rotating before the second rotating disk when the rotating shaft rotates counterclockwise. A top view of the first plate and the second plate of a modified example. 10 is a side view of the rotating shaft, the modified second plate, and the second rotating disk, showing the state when the modified second plate is sealing the second through hole of the second rotating disk. FIG.

[0017] An embodiment of a flow path switching device according to the present disclosure will be described.

[0018] [Overview of Flow Path Switching Device] FIG. 1 shows a perspective view of the flow path switching device 1 of this embodiment. FIG. 2 shows a front view of the flow path switching device 1. FIG. 3 shows a plan view of the flow path switching device 1. FIG. 4 shows a bottom view of the flow path switching device 1. FIG. 5 shows an exploded perspective view of the flow path switching device 1. FIG. 6 shows a cross-sectional view of the flow path switching device 1 taken along line A-A in FIG. 2. FIG. 7 shows a cross-sectional view of the flow path switching device 1 taken along line B-B in FIG. 3. The control unit 5 is not shown in FIGS. 2 to 7. As shown in FIGS. 1 to 7, the flow path switching device 1 includes a housing 2, a valve body unit 3 arranged inside the housing 2, a drive unit 4 that drives the valve body unit 3, and a control unit 5 that controls the drive unit 4.

[0019] 1 to 7 , the housing 2 includes an upper housing 11 and a lower housing 12, and is configured by fastening the housings 11, 12 together with a plurality of screws 6. The housing 2 includes inlet / outlet passages 20 through which a fluid flows in and out. The flow path switching device 1 of this embodiment is configured as an eight-way valve, for example, and the housing 2 has eight inlet / outlet passages 20. As the eight inlet / outlet passages 20, a first inlet / outlet passage 21, a second inlet / outlet passage 22, a third inlet / outlet passage 23, and a fourth inlet / outlet passage 24 are provided in the upper housing 11, and a fifth inlet / outlet passage 25, a sixth inlet / outlet passage 26, a seventh inlet / outlet passage 27, and an eighth inlet / outlet passage 28 are provided in the lower housing 12.

[0020] FIG. 8 is a perspective view showing the inside of the upper housing 11. As shown in FIG. 8, the upper housing 11 has an opening 21a for the first inflow / outflow passage 21, an opening 22a for the second inflow / outflow passage 22, an opening 23a for the third inflow / outflow passage 23, and an opening 24a for the fourth inflow / outflow passage 24. Similarly, as shown in FIG. 5, the lower housing 12 has openings 25a, 26a, 27a, and 28a for the fifth inflow / outflow passage 25 to the eighth inflow / outflow passage 28. The inflow / outflow passage 20 corresponds to an example of a "communication passage" provided in a "housing" in the disclosed technology. In this embodiment, the housing 2 is formed, for example, from resin.

[0021] 5 to 7 , the valve body 3 rotates in the housing 2 and includes a first rotating disk 13 and a second rotating disk 14 stacked one above the other, and a rotating shaft 15 that drives and rotates the rotating disks 13, 14. The rotating disks 13, 14 are stacked in the axial direction X. The first rotating disk 13 is an example of a "first driving member" in the disclosed technology, and the second rotating disk 14 is an example of a "second driving member" in the disclosed technology. The rotating disks 13, 14 and the rotating shaft 15 are formed of, for example, resin.

[0022] [Regarding the first rotating disk] Fig. 9 shows a perspective view of the first rotating disk 13. Fig. 10 shows a plan view of the first rotating disk 13. Fig. 11 shows a bottom view of the first rotating disk 13. Fig. 12 shows a perspective view of the first rotating disk 13 taken along line CC in Fig. 10. As shown in Figs. 5 to 7, the first rotating disk 13 is housed inside the housing 2 together with the second rotating disk 14. As shown in Figs. 9 to 12, the first rotating disk 13 is formed in a substantially cylindrical shape with a bottom, and includes two rotation passages 30 that open upward in the axial direction X.

[0023] Two rotational passages 30 are provided, a first rotational passage 31 and a second rotational passage 32. The rotational passage 30 has a semicircular arc shape in a plan view. The rotational passage 30 corresponds to an example of a "communication passage" provided in a "first driving member" of the disclosed technology. A first shaft hole 13a, through which the rotational shaft 15 passes, is formed in the center of the first rotating disk 13. A first boss 13b is formed in the first rotating disk 13, centered on the first shaft hole 13a.

[0024] [Regarding the second rotating disk] Fig. 13 shows a perspective view of the second rotating disk 14. Fig. 14 shows a plan view of the second rotating disk 14. Fig. 15 shows a bottom view of the second rotating disk 14. Fig. 16 shows a perspective view of the second rotating disk 14 taken along line D-D in Fig. 14. As shown in Figs. 13 to 16, the second rotating disk 14 is formed in a substantially cylindrical shape with a bottom, similar to the first rotating disk 13, and includes two rotation passages 40 that open downward in the axial direction X.

[0025] Two rotational passages 40 are provided, namely, a third rotational passage 43 and a fourth rotational passage 44. These rotational passages 40 are semicircular in shape when viewed from the bottom. These rotational passages 40 correspond to an example of a "communication passage" provided in a "second drive member" of the disclosed technology. A second shaft hole 14a, through which the rotational shaft 15 passes, is also formed in the center of the second rotating disk 14. As shown in FIG. 14 , a second boss 14b is formed on the upper surface of the second rotating disk 14, centered on the second shaft hole 14a.

[0026] [Regarding the Rotating Shaft] Figure 17 shows a perspective view of the rotating shaft 15. Figure 18 shows a cross-sectional view of the rotating shaft 15 taken along line E-E in Figure 17. As shown in Figures 17 and 18, the rotating shaft 15 of this embodiment is formed in multiple stages with different outer diameters in different locations. The upper end 15a of the rotating shaft 15, which is connected to the drive unit 4, is a gear with multiple teeth. The lower end 15b of the rotating shaft 15, which is fitted into the shaft hole 12a of the lower housing 12, has a small diameter and an irregular shape. A pair of first and second protrusions 15c and 15d, which are arranged on the same circumference, are provided on the outer periphery of the middle part of the rotating shaft 15.

[0027] As shown in Figure 18, the protrusions 15c, 15d protrude in an arc shape from the outer periphery of the rotary shaft 15 and are arranged at intervals of 180 degrees. The first protrusion 15c has a longer circumferential length than the second protrusion 15d. Here, it is preferable that the protrusions 15c, 15d are arranged in two or more locations to ensure stable engagement with the first rotary disc 13 and the second rotary disc 14, and it is also preferable that the protrusions be arranged and shaped asymmetrically to prevent incorrect assembly.

[0028] 5 to 7, the rotary shaft 15 is provided to penetrate the upper housing 11 and both rotary disks 13, 14. The upper end 15a of the rotary shaft 15 penetrates the through-hole 11a of the upper housing 11 and is connected to the drive unit 4, and the lower end 15b is rotatably supported by the shaft hole 12a of the lower housing 12.

[0029] 6 and 7, a bearing 51 that rotatably supports the rotating shaft 15 is provided in the through hole 11a of the upper housing 11. The bearing 51 supports the rotating shaft 15 with an inner ring to ensure smooth rotation of the rotating shaft 15. Furthermore, a lip seal 55 that prevents fluid leakage is provided in the through hole 11a between the upper housing 11 and the rotating shaft 15. The rotating shaft 15 can also be made of metal.

[0030] [Regarding the Rotational Transmission Mechanism] The flow path switching device 1 of this embodiment includes a rotational transmission mechanism for transmitting the rotational force of the rotating shaft 15 to the first rotating disk 13 and the second rotating disk 14. Figure 19 shows the flow path switching device 1 in a cross-sectional view taken along line F-F in Figure 2. The rotational transmission mechanism of this embodiment is provided between the first rotating disk 13 and the second rotating disk 14 and the rotating shaft 15, and is configured to allow relative movement of the first rotating disk 13 and the second rotating disk 14 in the axial direction X of the rotating shaft 15, and to be able to partially release the transmission of the rotational force of the rotating shaft 15 to the first rotating disk 13 and the second rotating disk 14 as the rotating shaft 15 rotates.

[0031] In this embodiment, both rotating disks 13, 14 and the rotating shaft 15 are connected to be relatively movable in the rotational direction Y and the axial direction X. That is, as shown in Fig. 19, the rotating shaft 15 is assembled to the first boss 13b so as to coincide with the center of the first boss 13b of the first rotating disk 13. As shown in Figs. 11, 12 and 19, the first boss 13b has a pair of first notches 13c, 13d in which part of its circumferential direction is missing.

[0032] As shown in Figure 19, the first protrusions 15c and second protrusions 15d are fitted into these first notches 13c, 13d. Gaps 16 are provided in the circumferential direction between the first notches 13c, 13d and the first protrusions 15c and second protrusions 15d. Therefore, the rotating shaft 15 and the first rotating disk 13 are allowed to move relatively in the axial direction X along the first notches 13c, 13d and the protrusions 15c, 15d, and are allowed to move relatively in the rotational direction Y within the range of the gaps 16 between the first notches 13c, 13d and the protrusions 15c, 15d. In this way, the rotating shaft 15 is connected to the first rotating disk 13 so as to be able to move relatively in the rotational direction Y and the axial direction X.

[0033] On the other hand, similar to the first rotating disk 13, the rotating shaft 15 is assembled to the second boss 14b of the second rotating disk 14 so as to coincide with the center of the second boss 14b. Similar to the first boss 13b, the second boss 14b has a pair of second notches 14c, 14d, which are missing portions in the circumferential direction, as shown in FIGS. 14 and 16 . The first protrusion 15c and the second protrusion 15d are fitted into these second notches 14c, 14d. Circumferential gaps 16 are also provided between the second notches 14c, 14d and the protrusions 15c, 15d. Therefore, the rotating shaft 15 and the second rotating disk 14 are allowed to move relative to each other in the axial direction X along the second notches 14c, 14d and the protrusions 15c, 15d, and are allowed to move relative to each other in the rotational direction Y within the range of the gaps 16 between the second notches 14c, 14d and the protrusions 15c, 15d. In this way, the rotating shaft 15 is connected to the second rotating disk 14 so as to be movable relative to the second rotating disk 14 in the rotational direction Y and the axial direction X.

[0034] The rotating shaft 15 rotates by receiving driving force from the drive unit 4, and rotates relative to each other within the gap 16 at each boss 13b, 14b, and rotates integrally with both rotating disks 13, 14 by engaging with the circumferential inner surfaces of each notch 13c, 13d and each notch 14c, 14d.

[0035] [Regarding the Spring] As shown in Fig. 6 and other figures, a spring 61 is provided in an internal space IS provided between the first rotating disk 13 and the second rotating disk 14. This spring 61 urges the first rotating disk 13 and the second rotating disk 14 in a direction that separates them from each other and brings them closer to the housing 2. The spring 61 is an example of the "elastic member" of the present disclosure.

[0036] [Regarding the sealing members] As shown in Figures 5 to 7, 9, 10 and 15, in this embodiment, a first sealing member 17 and a second sealing member 18 are provided between the first rotating disk 13 and the second rotating disk 14 and the housing 2 (upper housing 11 and lower housing 12) to prevent fluid leakage.

[0037] The first seal member 17 is provided on the first rotating disk 13, and the second seal member 18 is provided on the second rotating disk 14. That is, as shown in Figures 9 and 10, a surrounding groove 13e is formed on the upper surface of the first rotating disk 13 so as to surround the periphery of the openings of the two rotational passages 30 (first rotational passage 31 and second rotational passage 32). The first seal member 17 is fitted and fixed in the surrounding groove 13e, and is provided so as to protrude from the upper surface of the first rotating disk 13.

[0038] 15 and 16 , a surrounding groove 14e is formed on the underside of the second rotating disk 14 so as to surround the periphery of the openings of the two rotational passages 40 (the third rotational passage 43 and the fourth rotational passage 44). The second seal member 18 is fitted and fixed in the surrounding groove 14e and is provided so as to protrude from the underside of the second rotating disk 14. In this embodiment, the seal members 17, 18 are made of rubber only. However, the seal members 17, 18 may also be made of a fluororesin (e.g., Teflon (registered trademark)) or rubber coated with a fluororesin.

[0039] [Regarding the Drive Unit] The drive unit 4 includes a motor or the like (not shown) for applying a rotational driving force to the rotary shaft 15. The drive unit 4 corresponds to an example of a "drive means" in the disclosed technology. The flow path switching device 1 selectively switches and forms a plurality of flow paths by combining and connecting the rotation passages 30, 40 of the rotary disks 13, 14 with the inflow / outflow passages 20 (the first inflow / outflow passage 21 to the eighth inflow / outflow passage 28) of the housing 2 by driving the rotary disks 13, 14 to rotate via the rotary shaft 15 with the drive unit 4, thereby forming a plurality of "flow path switching patterns" (described later).

[0040] [Regarding the control unit] The control unit 5 drives the rotary shaft 15 to rotate, thereby rotating the first rotary disk 13 and the second rotary disk 14, and after completing the switching of the flow path, controls the drive unit 4 to drive the rotary shaft 15 to rotate in the reverse direction, thereby releasing the proximity of the first rotary disk 13 and the second rotary disk 14 in the axial direction X. The control unit 5 corresponds to an example of the "control means" of the disclosed technology.

[0041] [Regarding the Flow Path Switching Pattern] Here, an example of the flow path switching pattern will be described. Fig. 20 relates to a "first pattern" of the flow path switching pattern and shows the rotational position of the first rotating disk 13 relative to the upper housing 11 in a schematic cross-sectional view taken along line G-G in Fig. 2. In Fig. 20, the outline of the upper housing 11, which does not appear in the cross-section, is shown by a two-dot chain line. Fig. 21 also relates to the "first pattern" and shows the rotational position of the second rotating disk 14 relative to the lower housing 12 in a schematic cross-sectional view taken along line H-H in Fig. 2. In Fig. 21, the outline of the lower housing 12, which does not appear in the cross-section, is shown by a two-dot chain line.

[0042] Fig. 22 is a schematic diagram equivalent to Fig. 20 showing the rotational position of the first rotating disk 13 relative to the upper housing 11, relating to the "second pattern" of the flow path switching pattern. Fig. 23 is a schematic diagram equivalent to Fig. 21 showing the rotational position of the second rotating disk 14 relative to the lower housing 12, relating to the "second pattern". Fig. 24 is a schematic diagram equivalent to Fig. 20 showing the rotational position of the first rotating disk 13 relative to the upper housing 11, relating to the "third pattern" of the flow path switching pattern. Fig. 25 is a schematic diagram equivalent to Fig. 21 showing the rotational position of the second rotating disk 14 relative to the lower housing 12, relating to the "third pattern".

[0043] 20 and 21 , in the first pattern, depending on the rotational positions of the first rotating disk 13 and the second rotating disk 14, the first rotational passage 31 of the first rotating disk 13 communicates with the first inflow / outflow passage 21 and the second inflow / outflow passage 22, and the second rotational passage 32 communicates with the third inflow / outflow passage 23 and the fourth inflow / outflow passage 24. In addition, the third rotational passage 43 of the second rotating disk 14 communicates with the fifth inflow / outflow passage 25 and the sixth inflow / outflow passage 26, and the fourth rotational passage 44 communicates with the seventh inflow / outflow passage 27 and the eighth inflow / outflow passage 28.

[0044] In this state, as shown by the arrows in Fig. 20, the fluid that has flowed into the first inflow / outflow passage 21 flows out from the second inflow / outflow passage 22 via the first rotation passage 31, and the fluid that has flowed into the fourth inflow / outflow passage 24 flows out from the third inflow / outflow passage 23 via the second rotation passage 32. Also, as shown by the arrows in Fig. 21, the fluid that has flowed into the sixth inflow / outflow passage 26 flows out from the fifth inflow / outflow passage 25 via the third rotation passage 43, and the fluid that has flowed into the seventh inflow / outflow passage 27 flows out from the eighth inflow / outflow passage 28 via the fourth rotation passage 44.

[0045] 22 and 23 , in the second pattern, the first rotating disk 13 and the second rotating disk 14 rotate counterclockwise by approximately 60° from the state of the first pattern, and the first rotation passage 31 of the first rotating disk 13 communicates with the first inflow / outflow passage 21 and the third inflow / outflow passage 23, and the second rotation passage 32 communicates with the second inflow / outflow passage 22 and the fourth inflow / outflow passage 24. In addition, the third rotation passage 43 of the second rotating disk 14 communicates with the fifth inflow / outflow passage 25 and the sixth inflow / outflow passage 26, and the fourth rotation passage 44 communicates with the seventh inflow / outflow passage 27 and the eighth inflow / outflow passage 28.

[0046] In this state, as shown by the arrows in Fig. 22, the fluid that has flowed into the first inflow / outflow passage 21 flows out from the third inflow / outflow passage 23 via the first rotation passage 31, and the fluid that has flowed into the fourth inflow / outflow passage 24 flows out from the second inflow / outflow passage 22 via the second rotation passage 32. Also, as shown by the arrows in Fig. 23, the fluid that has flowed into the seventh inflow / outflow passage 27 flows out from the eighth inflow / outflow passage 28 via the fourth rotation passage 44, and the fluid that has flowed into the sixth inflow / outflow passage 26 flows out from the fifth inflow / outflow passage 25 via the third rotation passage 43.

[0047] 24 and 25 , in the third pattern, the first rotating disk 13 and the second rotating disk 14 are further rotated approximately 60° counterclockwise from the state in the second pattern, and the first rotating passage 31 of the first rotating disk 13 communicates with the third inflow / outflow passage 23 and the fourth inflow / outflow passage 24, and the second rotating passage 32 communicates with the first inflow / outflow passage 21 and the second inflow / outflow passage 22. In addition, the fourth rotating passage 44 of the second rotating disk 14 communicates with the sixth inflow / outflow passage 26 and the eighth inflow / outflow passage 28, and the third rotating passage 43 communicates with the fifth inflow / outflow passage 25 and the seventh inflow / outflow passage 27.

[0048] In this state, as shown by the arrows in Fig. 24, the fluid that has flowed into the first inflow / outflow passage 21 flows out from the second inflow / outflow passage 22 via the second rotation passage 32, and the fluid that has flowed into the fourth inflow / outflow passage 24 flows out from the third inflow / outflow passage 23 via the first rotation passage 31. Also, as shown by the arrows in Fig. 25, the fluid that has flowed into the seventh inflow / outflow passage 27 flows out from the fifth inflow / outflow passage 25 via the third rotation passage 43, and the fluid that has flowed into the sixth inflow / outflow passage 26 flows out from the eighth inflow / outflow passage 28 via the fourth rotation passage 44.

[0049] [Regarding the pressure relief structure for the internal space] When the pressure of the fluid in the rotational passage 30 of the first rotating disk 13 becomes greater than the elastic force of the spring 61 and the first rotating disk 13 is pushed down, the fluid in the rotational passage 30 leaks from the first sealing member 17 and flows into the internal space IS, causing the pressure in the internal space IS to increase.

[0050] Then, the first seal member 17 is compressed due to the pressure difference between the rotary passage 30 and the internal space IS, and the sliding torque of the first rotating disk 13 (i.e., the torque generated when the first seal member 17 slides on the upper housing 11 when the first rotating disk 13 rotates (i.e., when driven)) increases. Then, depending on the pressure difference between the rotary passage 30 and the internal space IS, the first rotating disk 13 may become difficult to rotate, and the flow path switching device 1 may not be able to selectively switch between the multiple flow paths.

[0051] Furthermore, the second seal member 18 is compressed due to the pressure difference between the rotary passage 40 and the internal space IS, and the sliding torque of the second rotating disk 14 (i.e., the torque generated when the second seal member 18 slides on the lower housing 12 when the second rotating disk 14 rotates) increases. As a result, depending on the pressure difference between the rotary passage 40 and the internal space IS, the second rotating disk 14 may become difficult to rotate, and the flow path switching device 1 may not be able to selectively switch between the multiple flow paths.

[0052] The same applies when the pressure of the fluid in the rotation passage 40 of the second rotating disk 14 becomes greater than the elastic force of the spring 61 and the second rotating disk 14 is pushed up.

[0053] Therefore, in this embodiment, a pressure relief structure for the internal space IS is provided to reduce the increased pressure in the internal space IS.

[0054] Specifically, as shown in Figure 26 etc., a first through-hole 71 for connecting the rotation passage 30 and the internal space IS is provided in the bottom surface 13f of the first rotating disk 13. Furthermore, as shown in Figure 27 etc., a second through-hole 72 for connecting the rotation passage 40 and the internal space IS is provided in the top surface 14f of the second rotating disk 14.

[0055] As shown in Figures 6, 7, 26, and 27, the internal space IS is provided with a first plate 81 for opening and sealing the first through hole 71, and a second plate 82 for opening and sealing the second through hole 72.

[0056] As shown in Figure 26 and other figures, the first plate 81 is a plate-shaped member and includes a disk portion 81a, a shaft hole 81b, a first fitting portion 81c, a second fitting portion 81d, and a protrusion 81e. Here, the disk portion 81a is a portion formed in a disk shape, and a shaft hole 81b is provided in the center, into which the rotating shaft 15 is inserted. The outer periphery of the shaft hole 81b is provided with a first fitting portion 81c that fits with a first protrusion 15c of the rotating shaft 15, and a second fitting portion 81d that fits with a second protrusion 15d of the rotating shaft 15. The protrusions 81e are generally trapezoidal, flat plate-shaped portions that protrude outward from the outer periphery of the disk portion 81a, and two protrusions are provided.

[0057] As shown in Figure 27 and other figures, the second plate 82 is a plate-shaped member and includes a disk portion 82a, a shaft hole 82b, a first fitting portion 82c, a second fitting portion 82d, and a protrusion 82e. Here, the disk portion 82a is a portion formed in a disk shape and has a shaft hole 82b in its center, into which the rotating shaft 15 is inserted. The outer periphery of the shaft hole 82b is provided with a first fitting portion 82c that fits with a first protrusion 15c of the rotating shaft 15, and a second fitting portion 82d that fits with a second protrusion 15d of the rotating shaft 15. The protrusions 82e are generally trapezoidal, flat plate-shaped portions that protrude outward from the outer periphery of the disk portion 82a, and two protrusions 82e are provided.

[0058] Note that the position where the first through hole 71 is provided and the position where the second through hole 72 is provided are different in the rotation direction Y of the rotating shaft 15 (i.e., the circumferential direction of the first rotating disk 13 and the second rotating disk 14). Therefore, as shown in Fig. 28 , the orientation of the first plate 81 and the orientation of the second plate 82 are different in the rotation direction Y of the rotating shaft 15, and the position where the protrusion 81e of the first plate 81 is provided and the position where the protrusion 82e of the second plate 82 is provided are different.

[0059] The first plate 81 and the second plate 82 rotate in conjunction with the rotation of the rotary shaft 15 to open and seal the first through-hole 71 and the second through-hole 72 .

[0060] Therefore, the operation of the flow path switching device 1 to switch the flow paths while depressurizing the internal space IS will be specifically described.

[0061] First, as shown in Fig. 29, when the rotating shaft 15 is stopped, the first through-hole 71 is sealed by the protrusion 81e of the first plate 81, thereby sealing the rotation passage 30 from the internal space IS. Also, as shown in Fig. 32, when the rotating shaft 15 is stopped, the second through-hole 72 is sealed by the protrusion 82e of the second plate 82, thereby sealing the rotation passage 40 from the internal space IS.

[0062] Therefore, a case where the rotary shaft 15 rotates clockwise (i.e., rotates in the first direction) from the state shown in FIG. 29 or FIG. 32 will be described.

[0063] 29 to the state shown in Fig. 30, the first fitting portion 81c of the first plate 81 fits into the first protrusion 15c of the rotating shaft 15, and the second fitting portion 81d of the first plate 81 fits into the second protrusion 15d of the rotating shaft 15, so the first plate 81 rotates clockwise in conjunction with the rotation of the rotating shaft 15. On the other hand, the first boss 13b of the first rotating disk 13 is not in contact with the first protrusion 15c or the second protrusion 15d of the rotating shaft 15, so the rotating shaft 15 rotates relative to the first rotating disk 13 within the range of the gap 16.

[0064] 30, when the rotating shaft 15 rotates to the right, the first plate 81 rotates to the right in conjunction with the rotation of the rotating shaft 15, before the first rotating disk 13. Therefore, the first through-hole 71 is opened by the protrusion 81e of the first plate 81, and the rotating passage 30 and the internal space IS communicate with each other.

[0065] 32 to the state shown in Fig. 33, the first fitting portion 82c of the second plate 82 fits into the first protrusion 15c of the rotating shaft 15, and the second fitting portion 82d of the second plate 82 fits into the second protrusion 15d of the rotating shaft 15, so the second plate 82 rotates rightward in conjunction with the rotation of the rotating shaft 15. On the other hand, the second boss 14b of the second rotating disk 14 is not in contact with the first protrusion 15c or the second protrusion 15d of the rotating shaft 15, so the rotating shaft 15 rotates relative to the second rotating disk 14 within the range of the gap 16.

[0066] 33, when the rotating shaft 15 rotates to the right, the second plate 82 rotates to the right in conjunction with the rotation of the rotating shaft 15, before the second rotating disk 14. Therefore, the second through-hole 72 is opened by the protrusion 82e of the second plate 82, and the rotating passage 40 and the internal space IS communicate with each other.

[0067] As a result, the pressure in the internal space IS that has increased as described above is released into the rotational passage 40 via the second through-hole 72. This reduces the pressure in the internal space IS, reducing the pressure difference between the rotational passage 40 and the internal space IS, making it difficult for the second seal member 18 to be compressed and reducing the sliding torque of the second rotating disk 14. This makes it easier for the second rotating disk 14 to rotate clockwise. This makes it possible to reliably rotate the second rotating disk 14 clockwise and selectively switch between multiple flow paths.

[0068] After the internal space IS is depressurized in this manner, the first protrusion 15c and the second protrusion 15d of the rotating shaft 15 come into contact with the first boss 13b of the first rotating disk 13, causing the rotating shaft 15 to rotate further to the right. As a result, the first rotating disk 13 rotates to the right in conjunction with the rotation of the rotating shaft 15, with the sliding torque reduced. In addition, the first protrusion 15c and the second protrusion 15d of the rotating shaft 15 come into contact with the second boss 14b of the second rotating disk 14, causing the rotating shaft 15 to rotate further to the right. As a result, the second rotating disk 14 rotates to the right in conjunction with the rotation of the rotating shaft 15, with the sliding torque reduced.

[0069] Furthermore, after the flow path switching is completed, the rotary shaft 15 rotates left. As a result, the first plate 81 rotates left in conjunction with the rotation of the rotary shaft 15, the first through-hole 71 is sealed by the protrusion 81 e of the first plate 81, and the rotary passage 30 is sealed from the internal space IS. Also, the second plate 82 rotates left in conjunction with the rotation of the rotary shaft 15, and the second through-hole 72 is sealed by the protrusion 82 e of the second plate 82, and the rotary passage 40 is sealed from the internal space IS.

[0070] On the other hand, a case where the rotary shaft 15 rotates counterclockwise from the state shown in FIG. 29 or FIG. 32 (that is, a case where the rotary shaft 15 rotates in a second direction opposite to the first direction) will be described.

[0071] 31 , when the rotating shaft 15 rotates left, the first plate 81 rotates left in conjunction with the rotation of the rotating shaft 15, prior to the first rotating disk 13, just as when the rotating shaft 15 rotates right. Therefore, the first through-hole 71 is opened by the protrusion 81 e of the first plate 81, and the rotation passage 30 and the internal space IS communicate with each other.

[0072] This reduces the pressure difference between the rotary passage 30 and the internal space IS, just as in the case where the rotary shaft 15 rotates clockwise, thereby reducing the sliding torque of the first rotary disk 13 and facilitating counterclockwise rotation of the first rotary disk 13. Therefore, the first rotary disk 13 can be reliably rotated counterclockwise to selectively switch between a plurality of flow paths.

[0073] 34, when the rotating shaft 15 rotates left, the second plate 82 rotates left in conjunction with the rotation of the rotating shaft 15, prior to the second rotating disk 14, just as when the rotating shaft 15 rotates right. Therefore, the second through-hole 72 is opened by the protrusion 82e of the second plate 82, and the rotation passage 40 and the internal space IS communicate with each other.

[0074] This reduces the pressure difference between the rotary passage 40 and the internal space IS, just as in the case where the rotary shaft 15 rotates clockwise, thereby reducing the sliding torque of the second rotary disk 14 and facilitating counterclockwise rotation of the second rotary disk 14. Therefore, the second rotary disk 14 can be reliably rotated counterclockwise to selectively switch between a plurality of flow paths.

[0075] After the internal space IS has been depressurized in this manner, the first protrusion 15c and the second protrusion 15d of the rotating shaft 15 come into contact with the first boss 13b of the first rotating disk 13, causing the rotating shaft 15 to rotate further to the left. As a result, the first rotating disk 13 rotates left in conjunction with the rotation of the rotating shaft 15, with the sliding torque reduced. In addition, the first protrusion 15c and the second protrusion 15d of the rotating shaft 15 come into contact with the second boss 14b of the second rotating disk 14, causing the rotating shaft 15 to rotate further to the left. As a result, the second rotating disk 14 rotates left in conjunction with the rotation of the rotating shaft 15, with the sliding torque reduced.

[0076] Furthermore, after the flow path switching is completed, the rotary shaft 15 rotates clockwise. As a result, the first plate 81 rotates clockwise in conjunction with the rotation of the rotary shaft 15, the first through-hole 71 is sealed by the protrusion 81 e of the first plate 81, and the rotary passage 30 is sealed from the internal space IS. Also, the second plate 82 rotates clockwise in conjunction with the rotation of the rotary shaft 15, the second through-hole 72 is sealed by the protrusion 82 e of the second plate 82, and the rotary passage 40 is sealed from the internal space IS.

[0077] [Operation and effect of the flow path switching device] When the pressure of the fluid in the rotary passage 30 exceeds the elastic force of the spring 61, the first rotary disk 13 is pushed down, causing the fluid in the rotary passage 30 to leak through the first seal member 17 and flow into the internal space IS, thereby increasing the pressure in the internal space IS. Furthermore, when the pressure of the fluid in the rotary passage 40 exceeds the elastic force of the spring 61, the second rotary disk 14 is pushed up, causing the fluid in the rotary passage 40 to leak through the second seal member 18 and flow into the internal space IS, thereby also increasing the pressure in the internal space IS.

[0078] As a countermeasure against this increase in pressure in the internal space IS, in the flow path switching device 1 of this embodiment, a first through hole 71 is provided in the first rotating disk 13, and a second through hole 72 is provided in the second rotating disk 14.

[0079] This allows the increased pressure in the internal space IS to be released to the rotary passage 30 via the first through-hole 71, and also to the rotary passage 40 via the second through-hole 72. Therefore, the pressure in the internal space IS can be lowered, thereby reducing the pressure difference between the rotary passage 30 and the internal space IS, and also reducing the pressure difference between the rotary passage 40 and the internal space IS. This reduces the sliding torque of the first rotating disk 13 and the second rotating disk 14, making it easier to rotate the first rotating disk 13 and the second rotating disk 14. Therefore, regardless of the magnitude of the fluid pressure in the rotary passage 30 and the rotary passage 40, the first rotating disk 13 and the second rotating disk 14 can be reliably rotated, and multiple flow paths can be selectively switched.

[0080] Furthermore, by providing the first through-holes 71 in the first rotating disk 13 and the second through-holes 72 in the second rotating disk 14, the pressure-receiving areas of the first rotating disk 13 and the second rotating disk 14 can be reduced. This makes it possible to suppress the fluid pressure received by the first rotating disk 13 and the second rotating disk 14. This therefore makes it possible to more effectively facilitate the rotation of the first rotating disk 13 and the second rotating disk 14.

[0081] In addition, a first plate 81 for opening and sealing the first through hole 71 and a second plate 82 for opening and sealing the second through hole 72 are provided in the internal space IS.

[0082] This allows the first plate 81 to open and seal the first through hole 71, and the second plate 82 to open and seal the second through hole 72, depending on the situation.

[0083] Therefore, when it is desired to lower the pressure in the internal space IS, the first through hole 71 is opened by the first plate 81 and the second through hole 72 is opened by the second plate 82, thereby allowing the pressure in the internal space IS to escape through the first through hole 71 to the rotating passage 30 and through the second through hole 72 to the rotating passage 40.

[0084] On the other hand, when it is desired to maintain the pressure in the internal space IS, the pressure in the internal space IS can be maintained by sealing the first through hole 71 with the first plate 81 and sealing the second through hole 72 with the second plate 82.

[0085] Furthermore, the first plate 81 and the second plate 82 rotate in conjunction with the rotation of the rotary shaft 15. When switching the flow path, the rotary shaft 15 rotates clockwise (or counterclockwise), causing the first plate 81 to open the first through hole 71, and the second plate 82 to open the second through hole 72. After the switching of the flow path is completed, the rotary shaft 15 rotates counterclockwise (or clockwise), causing the first plate 81 to seal the first through hole 71, and the second plate 82 to seal the second through hole 72.

[0086] As a result, when switching between the flow paths, the pressure in the internal space IS can be lowered, reducing the sliding torque of the first rotating disk 13 and the second rotating disk 14 and facilitating the rotation of the first rotating disk 13 and the second rotating disk 14. Therefore, regardless of the magnitude of the fluid pressure in the rotary passages 30 and 40, the first rotating disk 13 and the second rotating disk 14 can be reliably rotated, and multiple flow paths can be selectively switched between.

[0087] Furthermore, by maintaining the pressure in the internal space IS after the switching of the flow path is completed, the sealing performance of the first seal member 17 and the second seal member 18 can be ensured.

[0088] [Regarding Modified Plates] As a modified example, a first plate 91 and a second plate 92 as shown in Fig. 35 may be used instead of the first plate 81 and the second plate 82. Since the first plate 91 and the second plate 92 have the same shape, the following description will be given using the second plate 92 as a representative.

[0089] As shown in FIG. 35 , the second plate 92 includes a first plate member 101 and two second plate members 102 .

[0090] As shown in Figures 35 and 36, the first plate member 101 is formed of a first portion 111 having an approximately rectangular parallelepiped shape and a second portion 112 having an approximately rectangular parallelepiped shape whose short sides and long sides are smaller than those of the first portion 111.

[0091] The first plate member 101 also has a shaft hole 101b, a first fitting portion 101c, and a second fitting portion 101d. The shaft hole 101b, the first fitting portion 101c, and the second fitting portion 101d are formed to penetrate the first portion 111 and the second portion 112. The shaft hole 101b is a hole into which the rotating shaft 15 is inserted. The outer periphery of the shaft hole 101b is provided with the first fitting portion 101c that fits with the first protrusion 15c of the rotating shaft 15, and the second fitting portion 101d that fits with the second protrusion 15d of the rotating shaft 15. The first plate member 101 further has two through holes 101e that are formed to penetrate the first portion 111 and the second portion 112.

[0092] The second plate member 102 is formed in a flat plate shape, is attached to the first plate member 101 , and is a member that seals the second through-hole 72 of the second rotary disk 14 .

[0093] 35, the second plate member 102 is formed in a substantially C-shape when viewed from above, and is attached to the first plate member 101 with its cylindrical protruding portion 102a (i.e., the portion protruding toward the through-hole 101e of the first plate member 101) inserted into a circular mounting hole 112a provided in the second section 112 of the first plate member 101. At this time, it is conceivable that the protruding portion 102a provided with a snap fit is inserted into the mounting hole 112a, for example.

[0094] As shown in FIG. 36, the diameter of the mounting hole 112 a of the first plate member 101 is larger than the diameter of the protruding portion 102 a of the second plate member 102 .

[0095] 36 , the second plate member 102 can move relatively to the first plate member 101 and can rotate around the protrusion 102a in the direction of the arrow in the figure. That is, the second plate member 102 acts like a valve that opens and closes the second through-hole 72 of the second rotating disk 14, starting from the protrusion 102a, which corresponds to a hinge. In this way, the second plate member 102 seals the second through-hole 72 while being able to move relatively to the first plate member 101 so as to open and close the second through-hole 72.

[0096] The first plate member 101 has a wall portion 111a as a portion of the first portion 111 that protrudes beyond the second portion 112. Therefore, when the second plate member 102 receives fluid pressure from the second through-hole 72 and moves (i.e., rotates) in a direction that opens the second through-hole 72, the wall portion 111a comes into contact with the second plate member 102, thereby suppressing the movement of the second plate member 102.

[0097] According to this modification, the second plate 92 includes a first plate member 101 and two second plate members 102, and the second plate members 102 are capable of moving relative to the first plate member 101. Therefore, when the second through-hole 72 of the second rotating disk 14 is sealed by the second plate 92, even if there is variation in flatness of the surface around the second through-hole 72 of the second rotating disk 14, the second plate members 102 can move and come into close contact with the surface around the second through-hole 72 of the second rotating disk 14. Therefore, the sealing ability (i.e., sealing performance) of the second plate members 102 of the second plate 92 to seal the second through-hole 72 of the second rotating disk 14 can be improved.

[0098] Furthermore, by rotating the rotary shaft 15 to rotate the second plate 92, it is possible to reduce the sliding resistance that occurs between the second plate member 102 of the second plate 92 and the top surface 14f of the second rotating disk 14 when opening and sealing the second through-hole 72 of the second rotating disk 14. This ensures the drivability (i.e., ease of rotation) of the second plate 92 when opening and sealing the second through-hole 72.

[0099] Furthermore, since the second plate 92 can be manufactured simply by assembling the first plate member 101 and the second plate member 102, the manufacturing cost of the second plate 92 can be reduced.

[0100] Furthermore, in order to improve the sealing performance of the second plate member 102 of the second plate 92 sealing the second through hole 72 of the second rotating disk 14, there is no need to provide other parts or perform surface treatment on the second rotating disk 14 or the second plate 92, thereby reducing costs.

[0101] Furthermore, the diameter of the mounting hole 112a of the first plate member 101 is larger than the diameter of the protruding portion 102a of the second plate member 102, so a clearance (i.e., a gap) is provided between the mounting hole 112a and the protruding portion 102a. This allows the second plate member 102 to move toward the second rotating disk 14 when subjected to the pressure of the internal space IS, thereby improving the sealing performance with which the second plate member 102 seals the second through-hole 72 of the second rotating disk 14.

[0102] The portion of the second plate member 102 of the second plate 92 that seals the second through-hole 72 on the surface facing the second rotating disk 14 may be formed into a spherical shape. This can further improve the sealing performance of the second plate member 102 of the second plate 92 that seals the second through-hole 72 of the second rotating disk 14.

[0103] It should be noted that the above-described embodiments are merely examples and do not limit the present disclosure in any way. It goes without saying that various improvements and modifications are possible within the scope of the gist of the present disclosure.

[0104] For example, a through hole may be provided in only one of the first rotating disk 13 and the second rotating disk 14. That is, the first through hole 71 may be provided in the first rotating disk 13 while the second through hole 72 may not be provided in the second rotating disk 14, or the first through hole 71 may not be provided in the first rotating disk 13 while the second through hole 72 may be provided in the second rotating disk 14.

[0105] Furthermore, although the shapes of the first through hole 71 and the second through hole 72 are formed to be approximately rectangular in Figures 26 and 27, this is not limited to this and they may be formed to be circular, polygonal other than approximately rectangular, elongated hole-shaped, etc.

[0106] Furthermore, one of the first plate 81 and the second plate 82 may be molded integrally with the rotating shaft 15 .

[0107] Furthermore, although the above description has described the housing 2 having eight inlet / outlet passages 20, this is not limiting and the housing 2 may have a number of inlet / outlet passages 20 other than eight. Furthermore, although the above description has described the first rotating disk 13 including two rotary passages 30, this is not limiting and the first rotating disk 13 may include a number of rotary passages 30 other than two. Furthermore, although the above description has described the second rotating disk 14 including two rotary passages 40, this is not limiting and the second rotating disk 14 may include a number of rotary passages 40 other than two.

[0108] REFERENCE SIGNS LIST 1 flow path switching device 2 housing 3 valve body portion 4 drive portion 5 control portion 11 upper housing 12 lower housing 13 first rotating disk 13b first boss 13c first notch 13d first notch 13e surrounding groove 13f bottom surface portion 14 second rotating disk 14b second boss 14c second notch 14d second notch 14e surrounding groove 14f top surface portion 15 rotating shaft 15c first protrusion 15d second protrusion 16 gap 17 first seal member 18 second seal member 20 inflow / outflow passage 30 rotation passage 31 first rotation passage 32 second rotation passage 40 rotation passage 43 third rotation passage 44 fourth rotation passage 61 spring 71 first through hole 72 second through hole 81 first plate 81a Disk portion 81b Shaft hole 81c First fitting portion 81d Second fitting portion 81e Protrusion 82 Second plate 82a Disk portion 82b Shaft hole 82c First fitting portion 82d Second fitting portion 82e Protrusion 91 First plate 92 Second plate 101 First plate member 102 Second plate member 102a Protrusion 111 First portion 111a Wall portion 112 Second portion 112a Mounting hole X Axial direction Y Rotational direction IS Internal space

Claims

1. A flow path switching device comprising: a housing; and a valve body portion arranged inside the housing, wherein the valve body portion includes a first drive member and a second drive member arranged adjacent to each other; the housing and at least one of the first drive member and the second drive member each include a plurality of communication passages; a sealing member for suppressing fluid leakage is provided between the housing and the periphery of the communication passages in at least one of the first drive member and the second drive member; and by driving the first drive member and the second drive member, the communication passages in at least one of the first drive member and the second drive member and the communication passages in the housing are combined and connected to selectively switch between a plurality of flow paths, wherein an internal space provided between the first drive member and the second drive member is provided with an elastic member that separates the first drive member and the second drive member from each other and urges them in a direction to approach the housing; and at least one of the first drive member and the second drive member is provided with a through hole for communicating the communication passages with the internal space, A flow path switching device characterized by the above.

2. A flow path switching device according to claim 1, characterized in that a plate for opening and sealing the through hole is provided in the internal space.

3. A flow path switching device according to claim 2, wherein the valve body portion includes a rotary shaft that rotates the first drive member and the second drive member, and the plate rotates in conjunction with the rotation of the rotary shaft, and when switching the flow path, the rotary shaft rotates in a first direction and the plate opens the through hole, and thereafter, after the switching of the flow path is completed, the rotary shaft rotates in a second direction opposite to the first direction and the plate seals the through hole.

4. A flow path switching device according to claim 2 or 3, wherein the plate comprises a first plate member and a second plate member attached to the first plate member and sealing the through hole, and the second plate member seals the through hole while being movable relative to the first plate member so as to open and close the through hole.

Images