Flow path switching device

Abstract

Provided is a flow path switching device comprising a flow path member, an introduction flow path for introducing a fluid, a first lead-out flow path for leading out the fluid introduced from the introduction flow path, a second lead-out flow path for leading out the fluid introduced from the introduction flow path, a first valve seat provided between the introduction flow path and the first lead-out flow path in the flow path member, a second valve seat provided between the introduction flow path and the second lead-out flow path in the flow path member, a first valve body that is brought into contact with and separates from the first valve seat, a second valve body that is brought into contact with and separates from the second valve seat, and a valve shaft to which the first valve body and the second valve body are attached, in which the flow path switching device is configured so that the first valve body and the second valve body are moved in the axial direction by the valve shaft, switching is performed between opening / closing of the first valve body and the first valve seat and opening / closing of the second valve body and the second valve seat, and the flow of the fluid introduced into the introduction flow path is thereby switched between the first lead-out flow path and the second lead-out flow path, and wherein the flow path member includes a first flow path member and a second flow path member joined between the introduction flow path and the first lead-out flow path, the first valve seat is formed from an elastic material having sealability and is formed integrally with a seal section for ensuring sealability in the vicinity of the joint between the first flow path member and the second flow path member, and the first valve seat and the seal section are sandwiched by and thereby fixed between the first flow path member and the second flow path member.

Description

Flow path switching device

[0001] The technology disclosed in this specification relates to a flow path switching device that switches a flow path of a fluid.

[0002] A conventional technique of this type is, for example, a valve device (flow path switching device) having a three-way poppet valve structure, as described in Patent Document 1 below. This device includes a first valve element and a second valve element that abut against or are spaced apart from a first valve seat and a second valve seat provided in a flow path of a housing (flow path member). The first valve element and the second valve element are attached at a distance from each other on a valve stem. The flow path includes an inlet (inlet flow path) through which the fluid flows, and a first outlet (first outlet flow path) and a second outlet (second outlet flow path) through which the fluid flows. The first valve seat is provided at the boundary between the inlet flow path and the first outlet flow path. The second valve seat is provided at the boundary between the inlet flow path and the second outlet flow path. The flow path member has a two-body structure formed by joining two flow path members. The two flow path members are joined between the inlet flow path and the first outlet flow path. The inlet flow path and the second outlet flow path are integrally formed. In this device, the valve stem is reciprocated in the axial direction by a motor (actuator), thereby bringing the first valve element into or out of contact with the first valve seat, and simultaneously bringing the second valve element into or out of contact with the second valve seat. This allows communication between the inlet flow path and the first outlet flow path to be established or blocked, and simultaneously allows communication between the inlet flow path and the second outlet flow path to be blocked or blocked. In this way, the flow path of the fluid flowing into the inlet flow path is switched between the first outlet flow path and the second outlet flow path.

[0003] JP 2024-30893 A

[0004] In the device described in Patent Document 1, a seal member is provided on the seating surface of each valve seat to ensure a seal against fluid between each valve element and its corresponding valve seat when the valve is closed. In contrast to this, it is conceivable to provide a seal member such as an O-ring near the joint between the two flow path members to ensure a seal. However, providing a separate seal member near the joint between the two flow path members increases the number of parts and assembly steps of the device, raising concerns about increased costs.

[0005] This disclosed technology has been made in consideration of the above circumstances, and its purpose is to provide a flow path switching device that ensures sealing between the valve seat and the valve body, as well as sealing near the joint between two flow path components, without increasing the number of parts or assembly labor.

[0006] (1) In order to achieve the above object, one aspect of the present disclosure provides a valve including a flow path member, an inlet flow path formed in the flow path member for introducing a fluid, a first outlet flow path formed in the flow path member for discharging the fluid introduced from the inlet flow path, a second outlet flow path formed in the flow path member for discharging the fluid introduced from the inlet flow path, a first valve seat provided in the flow path member between the inlet flow path and the first outlet flow path, a second valve seat provided in the flow path member between the inlet flow path and the second outlet flow path, a first valve body abutting and separating from the first valve seat, a second valve body abutting and separating from the second valve seat, and a valve stem to which the first valve body and the second valve body are attached, wherein the first valve body and the second valve body are axially movable by the valve stem. In this flow path switching device, the flow of a fluid introduced into an inlet flow path is switched between a first outlet flow path and a second outlet flow path by moving the first valve body and the first valve seat to open or close the first valve body and the second valve seat, and the flow path member includes a first flow path member and a second flow path member joined between the inlet flow path and the first outlet flow path, the first valve seat is made of an elastic material having sealing properties, and is integrally formed with a sealing portion for ensuring sealing properties near the joint between the first flow path member and the second flow path member, and the first valve seat and the sealing portion are fixed by being sandwiched between the first flow path member and the second flow path member.

[0007] According to this aspect, the first valve seat is formed integrally with the seal portion. Furthermore, because the first valve seat is formed from an elastic material with sealing properties, good sealing is achieved between the first valve body and the first valve seat when the first valve body is seated on the first valve seat. Furthermore, the first valve seat and the seal portion are fixed by being sandwiched between the first flow path member and the second flow path member when the first flow path member and the second flow path member are joined. Good sealing is achieved near the joint between the first flow path member and the second flow path member by the seal portion. Therefore, the first valve seat and the seal portion, which originally have different sealing functions, are combined into a single component. Furthermore, the first valve seat and the seal portion, which originally require different assembly procedures, can be assembled in a single assembly operation.

[0008] The technology described in (2) is the aspect of (1) above, wherein the first valve seat has a seat portion on which the first valve body can be seated and an outer ring portion formed on the outer periphery of the seat portion and sandwiched between the first flow path member and the second flow path member, and the sealing portion is formed on the outer periphery of the outer ring portion and has an annular shape, and its cross section cut in the axial direction has a circular shape that is thicker than the outer ring portion.

[0009] According to this aspect, the first valve seat has a seat portion on which the first valve body can be seated and an outer annular portion formed on the outer periphery of the seat portion and sandwiched between the first flow path member and the second flow path member. The seal portion is formed on the outer periphery of the outer annular portion and has an annular shape, and its cross section taken in the axial direction has a circular shape that is thicker than the outer annular portion. Therefore, when the seal portion and the outer annular portion are sandwiched between the first flow path member and the second flow path member, the seal portion, particularly the portion thicker than the outer annular portion, is compressed, thereby exhibiting sealing properties.

[0010] According to the technology described in (1), it is possible to ensure sealing between the first valve seat and the first valve body without increasing the number of parts and the assembly man-hours, and it is also possible to ensure sealing near the joint between the two flow path components.

[0011] According to the technique described in (2), the portion of the seal portion that exhibits sealing properties can be limited to a part of the seal portion, thereby increasing the durability of the seal portion.

[0012] 1 is a cross-sectional view showing an outline of a flow path switching device according to an embodiment; FIG. 2 is a cross-sectional view showing an exploded view of a flow path switching device excluding a drive unit according to an embodiment; FIG. 3 is a cross-sectional view showing a part of an assembly procedure of a valve unit according to an embodiment;

[0013] Hereinafter, a flow path switching device according to an embodiment will be described in detail with reference to the drawings.

[0014] [Configuration of the Flow Path Switching Device] Fig. 1 shows a schematic cross-sectional view of a flow path switching device 1 according to this embodiment. As shown in Fig. 1, this flow path switching device 1 has a three-way poppet valve structure. The flow path switching device 1 includes a valve unit 2 and a drive unit 3. The valve unit 2 includes a flow path housing 11 having a plurality of flow paths, a valve seat 12, a valve element 13, and a valve stem 14. The drive unit 3 includes an actuator 15. Fig. 2 shows an exploded cross-sectional view of the flow path switching device 1 excluding the drive unit 3 (actuator 15).

[0015] [Regarding the Valve Portion] The flow path housing 11 includes a valve chamber 20 that houses the valve element 13, one inlet flow path 21, and two outlet flow paths 22. The valve chamber 20 forms one end of the inlet flow path 21. The flow path housing 11 corresponds to an example of a "flow path member" in the technology disclosed herein. In this embodiment, the flow path housing 11 is formed from resin.

[0016] The inlet flow path 21 is a flow path through which fluid flows into the valve chamber 20. The outlet flow path 22 is a flow path through which fluid flows out of the valve chamber 20. The two outlet flow paths 22 include a first outlet flow path 221 and a second outlet flow path 222. The first outlet flow path 221 is provided on the actuator 15 side of the valve chamber 20. The second outlet flow path 222 is provided on the opposite side of the valve chamber 20 from the actuator 15.

[0017] The flow path housing 11 includes a first flow path housing 11A and a second flow path housing 11B, and has a two-piece structure formed by joining the two flow path housings 11A and 11B. The first flow path housing 11A and the second flow path housing 11B are joined between the inlet flow path 21 and the first outlet flow path 221. The first flow path housing 11A corresponds to an example of a "first flow path member" in the disclosed technology. The second flow path housing 11B corresponds to an example of a "second flow path member" in the disclosed technology.

[0018] The valve seat 12 includes a first valve seat 121 and a second valve seat 122. The first valve seat 121 is provided between the inlet flow path 21 (valve chamber 20) and the first outlet flow path 221. The second valve seat 122 is provided between the inlet flow path 21 (valve chamber 20) and the second outlet flow path 222. The first valve seat 121 and the second valve seat 122 are formed in an annular shape and have a first valve hole 16 and a second valve hole 17 in their centers, respectively. In this embodiment, the valve seats 121, 122 are formed from rubber having sealing properties. Rubber is an example of an "elastic member" in the disclosed technology.

[0019] The valve element 13 is attached to the lower part of the valve shaft 14. The valve element 13 opens and closes the first valve hole 16 and the second valve hole 17 by coming into contact with and separating from the valve seat 12. In this embodiment, the valve element 13 includes a first valve element 131 and a second valve element 132 that are spaced apart in the axial direction of the valve shaft 14. The first valve element 131 comes into contact with and separates from the first valve seat 121. The second valve element 132 comes into contact with and separates from the second valve seat 122. In this embodiment, the first valve element 131 and the second valve element 132 are made of resin. Each of the valve elements 131, 132 may also be made of metal.

[0020] The valve stem 14 is disposed between the flow path housing 11 and the actuator 15. The upper side of the valve stem 14 is disposed in the actuator 15. The lower side of the valve stem 14 is disposed in the valve chamber 20, and the valve element 13 is attached to the lower side. The valve stem 14 is capable of reciprocating in its axial direction (thrust direction). In this embodiment, the valve stem 14 is made of metal, but it can also be made of resin.

[0021] [Regarding the driving unit] The actuator 15 moves the valve element 13 in the axial direction together with the valve shaft 14. In this embodiment, the actuator 15 includes a movable core, a fixed core, a bobbin, a coil, a casing, etc., and is configured as a well-known "solenoid." In this embodiment, a detailed description of the actuator will be omitted.

[0022] [Operation of the Flow Path Switching Device] The flow path switching device 1 configured as described above can be switched between a first open valve state shown in Fig. 1 and a second open valve state (not shown) by axially moving the valve stem 14 with the actuator 15. That is, the flow path switching device 1 moves the first valve element 131 and the second valve element 132 in the axial direction with the valve stem 14 to switch between opening and closing the first valve element 131 and the first valve seat 121 and between opening and closing the second valve element 132 and the second valve seat 122. By this switching, the flow of the fluid introduced into the introduction flow path 21 is switched between the first outlet flow path 221 and the second outlet flow path 222.

[0023] 1 , the "first open valve state" refers to a state in which the first valve seat 121 and the first valve element 131 are fully open, and the second valve seat 122 and the second valve element 132 are fully closed. The "second open valve state" refers to a state in which the first valve seat 121 and the first valve element 131 are fully closed, and the second valve seat 122 and the second valve element 132 are fully open. The "fully closed state" refers to a state in which the valve elements 131 and 132 abut on the entire circumference of one end of each annular valve seat 121 and 122, thereby sealing the gap between each valve seat 121, 122 and each valve element 131, 132.

[0024] 1 , the fluid introduced from the inlet flow path 21 is discharged from the first outlet flow path 221. In the second open state, the fluid introduced from the inlet flow path 21 is discharged from the second outlet flow path 222.

[0025] [Regarding the Shape of the Valve Seats] The shapes of the valve seats 121, 122 in this embodiment will be described. As shown in FIGS. 1 and 2 , the first valve seat 121 has a thick seat portion 121a on the inner side and a thinner, annular outer ring portion 121b on the outer periphery of the seat portion 121a. The seat portion 121a has a minimum diameter at the first valve hole 16 and has inclined surfaces 121aa and 121ab that slope forward and backward. The first valve body 131 can be seated on one of the inclined surfaces 121aa of the seat portion 121a. The first valve seat 121 further has a seal portion 121c formed on the outer periphery of the outer ring portion 121b. The seal portion 121c has an annular shape, and its axial cross section has a thicker circular shape than the outer ring portion 121b. The seal portion 121c is a portion for ensuring sealing in the vicinity of the joint between the first flow path housing 11A and the second flow path housing 11B. The seat portion 121a, the outer ring portion 121b, and the seal portion 121c are integrally formed from rubber, which is an elastic material.

[0026] As shown in Figures 1 and 2, the second valve seat 122, like the first valve seat 121, has a thick seat portion 122a on the inside and an outer ring portion 122b on the outer periphery of the seat portion 122a that is thinner than the seat portion 122a. The second valve seat 122 does not have a seal portion. The seat portion 122a has a minimum diameter at the second valve hole 17 and has inclined surfaces 122aaa and 122ab that slope forward and backward. The second valve body 132 can be seated on one of the inclined surfaces 122ab of the seat portion 122a. The seat portion 122a and the outer ring portion 122b are integrally formed from rubber, which is an elastic material.

[0027] In this embodiment, the first valve seat 121 and the seal portion 121c are fixed by being sandwiched between the first flow path housing 11A and the second flow path housing 11B. A cylindrical spacer 30 is disposed on the inner periphery of the valve chamber 20 of the second flow path housing 11B. The spacer 30 constitutes the second flow path housing 11B. The spacer 30 has a communication hole 30a that leads to the introduction flow path 21. The outer annular portion 121b of the first valve seat 121 is fixed by being sandwiched between the first flow path housing 11A and the spacer 30. Furthermore, the outer annular portion 122b of the second valve seat 122 is fixed by being sandwiched between the second flow path housing 11B and the spacer 30.

[0028] [Assembly of the valve section] The assembly of the valve section 2 will now be described. Figure 3 shows a cross-sectional view of part of the procedure for assembling the valve section 2. To assemble the components of the valve section 2, the valve stem 14 is inserted through the first valve seat 121, the spacer 30, and the second valve seat 122. In this state, the first valve seat 121 and the second valve seat 122 are attached to the valve stem 14 with the components 121, 30, and 122 sandwiched therebetween.

[0029] 3, the second valve seat 122 and the spacer 30 are placed in the second flow path housing 11B, and the second valve seat 122 is sandwiched between the second flow path housing 11B and the spacer 30. In addition, the first valve seat 121 is placed on the first flow path housing 11A and the spacer 30 near the outlet of the introduction flow path 21.

[0030] Then, the first flow path housing 11A is placed on the second flow path housing 11B, the first valve seat 121 is sandwiched between the first flow path housing 11A, the second flow path housing 11B, and the spacer 30, and in this state, the first flow path housing 11A and the second flow path housing 11B are fixed by fastening or the like. Thereafter, the actuator 15 is attached to the first flow path housing 11A, and the valve shaft 14 is connected to the actuator 15, thereby obtaining the flow path switching device 1 in the state shown in FIG.

[0031] [Operations and Effects of the Flow Path Switching Device] The configuration of the flow path switching device 1 of this embodiment described above provides the following operations and effects in addition to the opening and closing operations described above. That is, the first valve seat 121 of this flow path switching device 1 is integrally formed with the seal portion 121c. Furthermore, because the first valve seat 121 is formed of an elastic material with sealing properties, excellent sealing is achieved between the first valve body 131 and the first valve seat 121 when the first valve body 131 is seated on the first valve seat 121. Furthermore, when the first flow path housing 11A and the second flow path housing 11B are joined together, the first valve seat 121 and the seal portion 121c are sandwiched and fixed between the first flow path housing 11A and the second flow path housing 11B. Excellent sealing is achieved near the joint between the first flow path housing 11A and the second flow path housing 11B by the seal portion 121c. Therefore, the first valve seat 121 and the seal portion 121c, which originally have different sealing functions, are combined into a single component. Furthermore, the first valve seat 121 and the seal portion 121c, which would normally require different assembly procedures, can be assembled in a single assembly operation. This ensures sealing between the first valve seat 121 and the first valve body 131, as well as sealing near the joint between the two flow path housings 11A, 11B, without increasing the number of parts or assembly steps.

[0032] According to the configuration of this embodiment, the first valve seat 121 includes a seat portion 121a on which the first valve body 131 can be seated, and an outer annular portion 121b formed on the outer periphery of the seat portion 121a and sandwiched between the first flow path housing 11A and the second flow path housing 11B. The seal portion 121c is formed on the outer periphery of the outer annular portion 121b and has an annular shape. Its axial cross section is thicker than that of the outer annular portion 121b. Therefore, when the seal portion 121c and the outer annular portion 121b are sandwiched between the first flow path housing 11A and the second flow path housing 11B, the thicker portion of the seal portion 121c is compressed, thereby providing sealing performance. This allows the portion of the seal portion 121c that provides sealing performance to be limited to a portion of the seal portion 121c, thereby improving the durability of the seal portion 121c.

[0033] <Other Embodiments> The disclosed technology is not limited to the above-described embodiments, and can be implemented by appropriately modifying part of the configuration within the scope of the disclosed technology.

[0034] (1) In the above embodiment, the shape of the first valve seat is not limited to the shape shown in FIGS. 1 to 3 , and can be changed as appropriate to match the shape of the corresponding first valve body and the shapes of the first flow path housing and the second flow path housing.

[0035] (2) In the above embodiment, the spacer 30 is provided in the second flow path housing 11B. However, this spacer 30 can be omitted. In this case, the method of attaching the second valve seat to the second flow path housing may be changed. For example, the second valve seat may be press-fitted and fixed to the valve chest inlet of the second flow path housing.

[0036] The disclosed technology can be used in a fluid circuit through which a fluid flows.

[0037] DESCRIPTION OF SYMBOLS 1 Flow path switching device 11 Flow path housing (flow path member) 11A First flow path housing (first flow path member) 11B Second flow path housing (second flow path member) 12 Valve seat 121 First valve seat 121c Seal portion 122 Second valve seat 13 Valve body 131 First valve body 132 Second valve body 14 Valve stem 20 Valve chamber (inlet flow path) 21 Inlet flow path 22 Outlet flow path 221 First outlet flow path 222 Second outlet flow path

Claims

a first valve seat provided in the flow path member between the inlet flow path and the first outlet flow path; a second valve seat provided in the flow path member between the inlet flow path and the second outlet flow path; a first valve element abutting against and separating from the first valve seat; a second valve element abutting against and separating from the second valve seat; and a valve stem to which the first valve element and the second valve element are attached, wherein the first valve element and the second valve element are moved axially by the valve stem to switch between opening and closing the first valve element and the first valve seat and between opening and closing the second valve element and the second valve seat, thereby switching the flow of the fluid introduced into the inlet flow path between the first outlet flow path and the second outlet flow path, the flow path member includes a first flow path member and a second flow path member joined between the inlet flow path and the first outlet flow path, the first valve seat is formed from an elastic material having sealing properties and is integrally formed with a sealing portion for ensuring sealing properties near the joint between the first flow path member and the second flow path member, and the first valve seat and the sealing portion are fixed by being sandwiched between the first flow path member and the second flow path member.

2. A flow path switching device as described in claim 1, wherein the first valve seat has a seat portion on which the first valve body can be seated and an outer ring portion formed on the outer periphery of the seat portion and sandwiched between the first flow path member and the second flow path member, and the sealing portion is formed on the outer periphery of the outer ring portion, has an annular shape, and its cross section cut in the axial direction has a circular shape that is thicker than that of the outer ring portion.

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