Flow path switching device

Abstract

To secure sealing performance between a valve seat and a valve element and to secure sealing performance in the vicinity of a joint of two flow passage members without increasing the number of components and assembling man-hours.SOLUTION: The flow path switching device 1 switches the flow path of the fluid introduced into the introduction flow path 21 between the first lead-out flow path 221 and the second lead-out flow path 222 by moving the first valve body 131 and the second valve body 132 in the axial direction with the valve shaft 14 to switch between opening and closing of the first valve body 131 and the first valve seat 121 and between opening and closing of the second valve body 132 and the second valve seat 122. The flow path housing 11 includes a first flow path housing side 11A and a second flow path housing side 11B which are joined between the inlet flow path 21 and the first outlet flow path 221. The first valve seat 121 is formed of an elastic material having sealability, and a seal part 11A for securing sealability in the vicinity of a joint between the first flow passage housing 11B and the second flow passage housing 121c is integrally formed. The first valve seat 121 and the sealing portion 121c are sandwiched and fixed between the first flow path housing 11A and the second flow path housing 11B.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[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 body and a second valve body 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 body and the second valve body are attached at a distance from each other on a single 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 in which two flow path members are joined together. 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. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2024-30893 Summary of the Invention [Problem to be solved by the invention]

[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 response 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 would increase the number of parts and assembly steps in 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. [Means for solving the problem]

[0006] In order to achieve the above object, the technology described in claim 1 includes 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 against and separating from the first valve seat, a second valve body abutting against and separating from the second valve seat, and a valve stem to which the first valve body and the second valve body are attached, In the flow path switching device configured to switch the flow of a fluid introduced into an inlet flow path 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, 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.

[0007] According to the configuration of the above technology, 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 and second flow path members are joined. Good sealing is achieved near the joint between the first and second flow path members 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] In order to achieve the above object, the technology described in claim 2 is the technology 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 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 the configuration of the above technology, in addition to the effect of the technology described in claim 1, 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 cut 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. [Effects of the Invention]

[0010] According to the technology described in claim 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 number of assembly steps, and it is also possible to ensure sealing near the joint between the two flow path members.

[0011] According to the technology described in claim 2, in addition to the effect of the technology described in claim 1, the part of the sealing portion that exhibits sealing properties can be limited to a part of the sealing portion, thereby increasing the durability of the sealing portion. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view showing an outline of a flow path switching device according to an embodiment. [Figure 2] FIG. 2 is an exploded cross-sectional view of the flow path switching device excluding a drive unit according to one embodiment. [Figure 3] 10A to 10C are cross-sectional views illustrating a part of an assembly procedure of the valve unit in one embodiment. DETAILED DESCRIPTION OF THE INVENTION

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

[0014] [Configuration of 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] [About the valve] 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 a fluid flows into the valve chamber 20. The outlet flow path 22 is a flow path through which a 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 in which the two flow path housings 11A and 11B are joined together. 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 arranged at an interval 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 valve stem 14. 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] [About the drive 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 moving the valve shaft 14 in its axial direction using 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 using the valve shaft 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" is 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" is 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" is a state in which the valve elements 131, 132 abut against the entire circumference of one end of each annular valve seat 121, 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] [Valve seat shape] The shapes of the valve seats 121, 122 of 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 center side and an outer annular portion 121b on the outer periphery of the seat portion 121a that is thinner than the seat portion 121a and has an annular shape. 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 annular portion 121b. The seal portion 121c has an annular shape, and its axial cross section has a circular shape that is thicker than the outer annular 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 FIGS. 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 122aa 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. Here, a cylindrical spacer 30 is arranged 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 communicates with 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. In addition, 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] [About valve assembly] The assembly of the valve section 2 will now be described. Figure 3 shows, in cross section, 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 top of 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] [About the function and effect of the flow path switching device] The above-described configuration of the flow path switching device 1 of this embodiment provides the following actions and advantages in addition to the opening and closing operations. Specifically, the first valve seat 121 of the 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, a good seal is obtained 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. The seal portion 121c provides a good seal near the joint between the first flow path housing 11A and the second flow path housing 11B. Therefore, the first valve seat 121 and the seal portion 121c, which originally have different sealing functions, are integrated into a single component. Furthermore, the first valve seat 121 and the seal portion 121c, which originally require different assembly procedures, can be assembled in a single assembly operation. This makes it possible to ensure 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 a seal. Therefore, the portion of the seal portion 121c that provides a seal can be limited to a portion of the seal portion 121c, thereby improving the durability of the seal portion 121c.

[0033] <Another embodiment> The disclosed technology is not limited to the above-described embodiment, and part of the configuration can be appropriately modified within the scope of the disclosed technology.

[0034] (1) In the above embodiment, the shape of the first valve seat is not limited to that 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, but 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 configured to be press-fitted and fixed to the valve chest inlet of the second flow path housing. [Industrial Applicability]

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

[0037] 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 part 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 channel 22 Outlet channel 221 First outlet channel 222 Second outlet channel

Claims

1. A flow path member; an introduction 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 that comes into contact with and moves away from the first valve seat; a second valve body that comes into contact with and moves away from the second valve seat; a valve stem to which the first valve body and the second valve body are attached; a valve shaft configured to move the first valve body and the second valve body in an axial direction to switch between opening and closing a relationship between the first valve body and the first valve seat and between opening and closing a relationship between the second valve body and the second valve seat, thereby switching a flow of a fluid introduced into the introduction 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 made of an elastic material having sealing properties, and is integrally formed with a sealing portion for ensuring sealing properties in the vicinity of a joint between the first flow path member and the second flow path member; 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. A flow path switching device characterized by:

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

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