CN109424764B

CN109424764B - Flow path switching valve

Info

Publication number: CN109424764B
Application number: CN201810818937.8A
Authority: CN
Inventors: 田渕健资; 藤田尚敬
Original assignee: Fujikoki Corp
Current assignee: Fujikoki Corp
Priority date: 2017-08-31
Filing date: 2018-07-24
Publication date: 2022-03-15
Anticipated expiration: 2038-07-24
Also published as: JP6515154B2; JP2019044818A; CN109424764A

Abstract

The invention provides a flow path switching valve which can restrain processing cost and processing time and enables a refrigerant to smoothly flow in a main valve shell. A coupling body (25) for moving the main valve body (15) in accordance with the reciprocating movement of the first and second pistons (21, 22) is configured by plate members (coupling plates (25A, 25B)) arranged in a direction orthogonal to the seating surfaces of the first and second main valve seats (13, 14), and a connecting plate portion (25A) extending between the first and second pistons (21, 22) and the main valve body (15) is arranged at a position avoiding the ports (pA-pF) when viewed from a direction (left-right direction) orthogonal to the seating surfaces of the first and second main valve seats (13, 14).

Description

Flow path switching valve

Technical Field

The present invention relates to a flow path switching valve that switches flow paths by moving a valve body, and more particularly, to a flow path switching valve suitable for switching flow paths in a heat pump type air-cooling and heating system or the like.

Background

In general, a heat pump type air-cooling/heating system such as a room air conditioner or a car air conditioner includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and the like, and further includes a flow path switching valve (a four-way switching valve or a six-way switching valve) as a flow path (flow direction) switching means, and the operation modes (a cooling operation and a heating operation) are switched by the flow path switching valve.

As a flow path switching valve incorporated in the heat pump type cooling/heating system and the like, for example, a sliding type flow path switching valve as described in patent document 1 is known. The sliding flow path switching valve (six-way switching valve) includes a valve main body (main valve housing) having a sliding main valve element therein and an electromagnetic pilot valve (four-way pilot valve), and has a plurality of ports provided in a main valve housing, and the sliding main valve element is arranged to be slidable in the left-right direction. Two operation chambers are provided on the left and right sides of the sliding type main valve element of the main valve housing, the two operation chambers are connected to the compressor discharge side and the compressor suction side via pilot valves, and are formed by a pair of left and right piston-type spacers coupled to the sliding type main valve element, respectively, and the flow path switching is performed by selectively introducing and discharging a high-pressure fluid (refrigerant) into and from the two operation chambers by the pilot valves, and sliding the sliding type main valve element in the left and right direction by a pressure difference between the two operation chambers.

More specifically, the left and right pistons that define the two operating chambers are connected by a connecting body so as to be movable integrally, and a sliding type main valve element is fitted or fixed to an opening formed in the connecting body, and the sliding type main valve element slides on (a valve seat surface of) a main valve seat provided with a plurality of ports through the connecting body in accordance with reciprocating movement of the pistons based on introduction and discharge of a high-pressure fluid (refrigerant) into and from the two operating chambers. An inner cavity (communication path) having a size that selectively communicates two adjacent ports of the plurality of ports is formed in the sliding main spool, and the plurality of ports are selectively communicated via the inner cavity by the movement of the sliding main spool, whereby the flow path switching is performed.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 8-170864

Problems to be solved by the invention

However, in the conventional flow path switching valve as described above, the coupling body that couples the piston and the sliding main valve element is basically made of one plate material that is disposed so as to face the seat surface of the main valve seat (in other words, disposed parallel to the seat surface). Therefore, it is necessary to provide an opening in the coupling body so as not to obstruct the flow of the high-pressure fluid (refrigerant) in the main valve housing, and in particular, the processing cost and the processing man-hour may increase with respect to the flow of the high-pressure fluid (refrigerant) flowing in or out through a port other than the port communicating with the sliding main valve.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a flow path switching valve that can smoothly flow a refrigerant in a main valve housing while suppressing processing cost and processing man-hours.

Means for solving the problems

To achieve the above object, a flow path switching valve according to the present invention basically includes: a cylindrical main valve housing in which a piston and a main valve chamber are arranged; a main valve seat having a valve seat surface with a plurality of ports open; a sliding main valve element disposed in the main valve chamber so as to be movable in an axial direction and slidably abutting against the seat surface; and a connecting body for moving the main valve body in accordance with the reciprocating movement of the piston, wherein the flow path switching valve switches between ports that communicate by moving the main valve body in the main valve chamber via the connecting body, and wherein the connecting body is formed of one or more plates arranged in a direction orthogonal to a seat surface of the main valve seat, and a connecting plate portion extending between the piston and the main valve body is arranged at a position avoiding the ports when viewed in the direction orthogonal to the seat surface of the main valve seat.

In a preferred embodiment, the connecting plate portion is disposed at a position offset from the port in a direction perpendicular to the axis.

In another preferred aspect, the plurality of ports are open on the opposite side with respect to the axis of the main valve housing, and the main valve body is configured such that a pair of slide valve bodies are arranged back to back in a direction orthogonal to the seat surface of the main valve seat.

In another preferred aspect, the coupling body is provided with a stopper portion for restricting movement of the main valve element.

In another preferred form, the stopper abuts against the main valve housing.

In another preferred embodiment, the connecting member is formed of a pair of plate members having the same size and the same shape and arranged in opposite directions.

In another preferred aspect, the pair of plate materials is provided with a concavo-convex fitting portion for aligning the pair of plate materials with each other.

In another preferred form, a portion of the pair of sheets abut each other.

In another preferred embodiment, the connecting member is formed of a single plate material.

In another preferred aspect, the connecting member includes: a support plate portion that is slidably supported by fitting the main valve element in a direction orthogonal to a seat surface of the main valve seat, and that is integrally movable in an axial direction with the main valve element; and the web portion extending from the support plate portion to the piston.

In another preferred embodiment, the main valve housing has a piston portion in which the piston is disposed and a body portion in which the main valve element is disposed, and the piston portion and the body portion have different inner diameters.

Effects of the invention

In the flow path switching valve of the present invention, the coupling body for moving the main valve body in accordance with the reciprocation of the piston is formed of a plate member (coupling plate) arranged in a direction orthogonal to the seat surface of the main valve seat, and the connecting plate portion extending between the piston and the main valve body is arranged at a position avoiding the port when viewed in the direction orthogonal to the seat surface of the main valve seat. Therefore, since the connecting body can be manufactured by simple processing as compared with the conventional flow path switching valve described above, processing cost and processing man-hours can be suppressed, and the refrigerant in the main valve housing, particularly the refrigerant flowing into or flowing out of the port other than the port communicating with the main valve, does not collide with the connecting plate portion extending between the piston and the main valve, and therefore the refrigerant smoothly flows in the main valve housing.

The problems, structures, and operational effects other than those described above will be more apparent from the following embodiments.

Drawings

Fig. 1 is a vertical cross-sectional view showing a first communication state (during cooling operation) of a first embodiment of a flow path switching valve (six-way switching valve) according to the present invention.

Fig. 2 is a vertical cross-sectional view showing a second communication state (during heating operation) of the flow path switching valve (six-way switching valve) according to the first embodiment of the present invention.

Fig. 3 is an enlarged longitudinal sectional view of a main portion of the six-way switching valve shown in fig. 1.

Fig. 4 is a cross-sectional view along the line of sight U-U of fig. 1.

Fig. 5 is a perspective view showing a main valve body and a coupling body of a first embodiment of a flow path switching valve (six-way switching valve) according to the present invention.

Fig. 6 is a diagram showing a pair of coupling plates constituting a coupling body according to a first embodiment of a flow path switching valve (six-way switching valve) of the present invention in a separated state, where (a) is a side view, (B) is a top view, and (C) is a bottom view of (a).

Fig. 7 is a diagram showing another example of a pair of coupling plates constituting a coupling body according to the first embodiment of the flow path switching valve (six-way switching valve) of the present invention in a separated state, where (a) is a side view, (B) is a top view of (a), and (C) is a bottom view of (a).

Fig. 8 is an enlarged view of a four-way pilot valve used in a flow path switching valve (six-way switching valve) according to the present invention, where (a) is a vertical sectional view showing a first communication state (during cooling operation) (when power is turned off), and (B) is a vertical sectional view showing a second communication state (during heating operation) (when power is turned on).

Fig. 9 is a vertical cross-sectional view showing (the first communication state (during cooling operation)) of a second embodiment of a flow path switching valve (six-way switching valve) according to the present invention.

Fig. 10 is a cross-sectional view taken along line V-V of fig. 9.

Fig. 11 is a vertical cross-sectional view showing (the first communication state (during cooling operation)) of a third embodiment of a flow path switching valve (six-way switching valve) according to the present invention.

Fig. 12 is a cross-sectional view taken along line X-X of fig. 11.

Fig. 13 is a vertical cross-sectional view showing (the first communication state (during cooling operation)) of a fourth embodiment of a flow path switching valve (six-way switching valve) according to the present invention.

Fig. 14 is a cross-sectional view taken along the line of sight Y-Y of fig. 13.

Description of the symbols

1 six-way switching valve (flow path switching valve) (first embodiment)

2 six-way switching valve (flow path switching valve) (second embodiment)

3 six-way switching valve (flow path switching valve) (third embodiment)

4 six-way switching valve (flow path switching valve) (fourth embodiment)

10 six-way valve body

11 main valve casing

11A upper end side cover part

11B lower end side cover part

11a first piston part

11b second piston part

11c trunk

12 main valve chamber

13 first main valve seat (valve seat)

14 second main valve seat (valve seat)

15 main valve core

15A first spool

15B second spool

15a fitting projection of first spool

15b cylindrical portion of second spool

15e concave surface

16A first U-shaped turning passage (communication path)

16B second U-shaped turning passage (communication path)

16a communication hole

17 pressure chamber

18O-shaped ring

19 compression coil spring

21 first piston

22 second piston

25 connected body

25A, 25B a pair of connecting plates (plates)

25C one-piece connecting plate (plate) (third embodiment)

25a connecting plate part

25b mounting foot

25c support plate part

25d concave-convex fitting part

25e butt plate part (fourth embodiment)

25s stopper of connected body (second embodiment)

31 first action chamber

32 second motion chamber

51 upper side through passage (communication passage)

90 four-way pilot valve

pA, pB, pC, pD, pE, pF ports

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

< first embodiment >

Fig. 1 and 2 are vertical sectional views showing a six-way switching valve as a flow path switching valve according to a first embodiment of the present invention, fig. 1 being a view showing a first communication state (during cooling operation), and fig. 2 being a view showing a second communication state (during heating operation).

In the present specification, the expressions indicating the positions and the directions such as the up-down direction, the left-right direction, the front-back direction, and the like are provided for convenience in the drawings in order to avoid the complexity of the description, and are not limited to the positions and the directions in the state where the heat pump type air-cooling and heating system or the like is actually incorporated.

In the drawings, the gaps formed between the members, the distances between the members, and the like are drawn to be larger or smaller than the sizes of the respective constituent members in order to facilitate understanding of the invention.

The six-way switching valve 1 of the illustrated embodiment is a sliding type configuration used as a six-way switching valve in, for example, a heat pump type cooling and heating system, and basically includes: a cylinder type six-way valve body 10 and a single electromagnetic four-way pilot valve 90 as a pilot valve. The six ports of the six-way switching valve 1 according to the present embodiment are denoted by the same reference numerals as those of the ports pA to pF of the six-way switching valve described in patent document 1. The basic configuration of the heat pump type cooling and heating system including the six-way switching valve 1 is described in patent document 1 and the like.

[ Structure of six-way valve body 10 ]

The six-way valve body 10 has a cylindrical main valve housing 11 made of metal such as brass or stainless steel, and a first operation chamber 31, a first piston 21, a main valve chamber 12, a second piston 22, and a second operation chamber 32 are arranged in this main valve housing 11 in this order from one end side (upper end side). In the first and

second pistons

21 and 22, a spring-loaded spacer is attached to an inner circumferential surface of the main valve housing 11 in pressure contact with an outer circumferential portion thereof so as to airtightly partition the main valve housing 11.

More specifically, the main valve housing 11 has a larger diameter body portion 11c, a center hole is provided in a thick circular plate-shaped upper connection cap 11d airtightly attached to an upper end opening portion of the body portion 11c, a first piston portion 11a made of a (smaller diameter) pipe member is airtightly fixed to the center hole by brazing or the like, and the first piston 21 is disposed in the first piston portion 11 a. Similarly, a center hole is provided in a thick-walled disk-shaped lower connecting cover 11e airtightly attached to the lower end opening of the body portion 11c, a second piston portion 11b made of a (smaller-diameter) pipe member is airtightly fixed to the center hole by brazing or the like, and the second piston 22 is disposed in the second piston portion 11 b.

A double-acting, thick, circular-plate-shaped upper-end-cover member 11A is airtightly fixed to the upper end of (the first piston portion 11A of) the main valve housing 11 by brazing or the like, the upper-end-cover member 11A prevents upward movement of the first piston 21 that partitions the variable-capacity first operating chamber 31, a double-acting, thick, circular-plate-shaped lower-end-cover member 11B is airtightly fixed to the lower end of (the second piston portion 11B of) the main valve housing 11 by brazing or the like, and the lower-end-cover member 11B prevents downward movement of the second piston 22 that partitions the variable-capacity second operating chamber 32. Ports p11 and p12 for introducing and discharging high-pressure fluid (refrigerant) into and from the first operating chamber 31 and the second operating chamber 32 are respectively attached to the upper end side cover member 11A and the lower end side cover member 11B.

A total of six ports are provided in (the main valve chamber 12 of) the main valve housing 11.

More specifically, a first main valve seat (valve seat) 13 made of, for example, metal and having a flat surface (right surface) is airtightly fixed to (the inner periphery of) the body portion 11c of the main valve housing 11 at the left center of the main valve chamber 12 by brazing or the like, and three ports (ports pB, pA, and pF in order from the upper end) of a pipe joint extending leftward are arranged in the vertical direction (in the direction of the axis O) at substantially equal intervals on the valve seat surface of the first main valve seat 13.

Further, at the right center of the main valve chamber 12 (a position facing the first main valve seat 13, in other words, a position located on the opposite side of the axis O from the first main valve seat 13), a second main valve seat (valve seat) 14 made of, for example, metal having a flat seat surface (left surface) is airtightly fixed to (the inner periphery of) the body portion 11c of the main valve housing 11 by brazing or the like, and three ports (ports pC, pD, pE in order from the upper end side) formed of pipe joints extending rightward are arranged in the vertical direction (arranged in the direction of the axis O) on the seat surface of the second main valve seat 14 and are opened at substantially equal intervals.

The ports (port pB, port pA, port pF) provided in the first main valve seat 13 and the ports (port pC, port pD, port pE) provided in the second main valve seat 14 are set at positions facing each other (on the opposite side of the axis O), and in this example, the diameters of the ports pA to pF provided in the first main valve seat 13 and the second main valve seat 14 are set to be substantially the same.

In the main valve chamber 12, specifically, in the body portion 11c of the main valve housing 11, a sliding main valve element 15 having a race-track-shaped annular seal surface and a rectangular cross section is disposed so as to be movable in the axis O direction (vertical direction), and both side surfaces (left and right surfaces) of the main valve element 15 are slidably abutted against seat surfaces of the first main valve seat 13 and the second main valve seat 14, respectively. In this example, the main spool 15 has a dimension in the left-right direction slightly larger than the outer diameters of the first piston portion 11a and the second piston portion 11b of the main valve housing 11.

The main valve body 15 is made of, for example, synthetic resin, and a first spool 15A on the first main valve seat 13 side (left side) and a second spool 15B on the second main valve seat 14 side (right side) are arranged with their back surfaces aligned.

A first U-shaped steering passage (communication passage) 16A formed by a bowl-shaped recess is opened on the left side (the side opposite to the second slide valve body 15B side) of the first slide valve body 15A, and the size of the first U-shaped steering passage 16A is such a size that two ports (port pB and port pA, or port pA and port pF) adjacent to each other among three ports opening on the valve seat surface of the first main valve seat 13 can be selectively communicated. Further, a second U-shaped turning passage (communication passage) 16B formed of a bowl-shaped recess is opened on the right surface side (the side opposite to the first slide valve body 15A side) of the second slide valve body 15B, and the size of the second U-shaped turning passage 16B is a size that can selectively communicate two ports (port pC and port pD, or port pD and port pE) adjacent to each other among three ports opened in the seat surface of the second main valve seat 14.

On the other hand, a cylindrical portion 15B having substantially the same outer shape as the second spool 15B extends leftward on the left surface of the second spool 15B (the surface facing the first spool 15A), and a short cylindrical fitting projection 15A slightly smaller than the outer shape of the first spool 15A (in other words, the outer shape of the second spool 15B) projects rightward on the right surface of the first spool 15A (the surface facing the second spool 15B). By the fitting convex portion 15A being slidably fitted into the cylindrical portion 15B (the O-ring 18 is sandwiched between the stepped portions provided between the fitting convex portion 15A and the cylindrical portion 15B), the first spool 15A and the second spool 15B are slightly movable relative to each other in the left-right direction (the direction perpendicular to the axis O, and the direction in which the ports (port pB, port pA, port pF) provided in the first main valve seat 13 and the ports (port pC, port pD, port pE) provided in the second main valve seat 14 face each other, that is, the direction orthogonal to the valve seat surfaces of the first main valve seat 13 and the second main valve seat 14), and are integrally movable in the up-down direction (the axis O direction).

The arrangement relationship between the fitting convex portion 15A of the first spool 15A and the cylindrical portion 15B of the second spool 15B may be reversed. That is, the first spool 15A and the second spool 15B may be integrated by providing a cylindrical portion in the first spool 15A, providing a fitting convex portion in the second spool 15B, and fitting the fitting convex portion of the second spool 15B into the cylindrical portion of the first spool 15A.

In the illustrated example, a slight gap is formed between (a portion inside the fitting convex portion 15A of) the right surface of the first spool 15A and (a portion inside the fitting convex portion 15A of) the left surface of the second spool 15B, a communication hole 16A formed by a lateral hole that communicates the first U-shaped steering passage 16A with the gap is provided in (a bottom portion of the first U-shaped steering passage 16A of) the first spool 15A, and an O-ring 18 as a sealing member is provided between the fitting convex portion 15A and the cylindrical portion 15B. Instead of the O-ring 18, a seal member such as a lip seal may be used.

Therefore, a portion inside the O-ring 18 including the gap is defined as a pressure chamber 17, and a high-pressure fluid (refrigerant) is introduced from a port (discharge-side high-pressure port) pA into the pressure chamber 17 through the first U-turn passage 16A and the communication hole 16A. The pressure chamber 17 and the main valve chamber 12 are sealed (closed) by the O-ring 18 disposed therebetween.

As can be seen from fig. 1, 2, and 3, the pressure receiving area Sb on the pressure chamber 17 side (right side) of the first spool 15A is larger than the pressure receiving area Sa on the first main valve seat 13 side (left side) as viewed in the left-right direction (direction perpendicular to the axis O).

More specifically, a projected area of the pressure chamber 17 with respect to a plane perpendicular to the left-right direction, that is, a projected area (pressure receiving area Sb) of a surface on which (the right surface of) the first spool 15A receives a pressure in the left-right direction due to the high-pressure refrigerant introduced into the pressure chamber 17 is larger than a projected area of the annular seal surface on the first main valve seat 13 side with respect to a plane perpendicular to the left-right direction, that is, a projected area (pressure receiving area Sa) of a surface on which (the left surface of) the first spool 15A receives a pressure in the right direction due to the high-pressure refrigerant flowing through the port (inside of the annular seal surface).

Thus, when the high-pressure refrigerant is introduced into the first U-shaped steering passage 16A through the port (discharge side high-pressure port) pA, and a part of the high-pressure refrigerant introduced into the first U-shaped steering passage 16A is filled into the pressure chamber 17 through the communication hole 16A, by the pressure received from the pressure chamber 17 (more specifically, the differential pressure between the pressure received from the pressure chamber 17 (high-pressure refrigerant) and the pressure received from the refrigerant flowing through the second U-turn passage 16B (low-pressure refrigerant)), the right surface (annular seal surface) of the second slide valve body 15B is pressed against the seat surface of the second main valve seat 14, the left surface (annular seal surface) of the first slide valve body 15A is pressed against the seat surface of the first main valve seat 13 by a differential pressure between the pressure received from the pressure chamber 17 (high-pressure refrigerant) and the pressure received from the refrigerant flowing through the first U-shaped steering passage 16A (high-pressure refrigerant).

In this example, a plurality of spring receiving holes 19a, 19B are formed in the right side of the first spool 15A and the left side of the second spool 15B (in the example of the figure, the portion facing the pressure chamber 17), compression coil springs 19 are compression-mounted in the spring receiving holes 19a and 19B (in the illustrated example, the compression coil springs 19 are vertically loaded at two positions between the right surface of the first spool 15A and the left surface of the second spool 15B), the compression coil spring 19 urges the first spool 15A and the second spool 15B in opposite directions (separation directions) to each other, thereby, the left surface (annular seal surface) of the first spool 15A is also pressed (pressed) against the seat surface of the first main valve seat 13, the right surface (annular seal surface) of the second spool 15B is pressed (pressed) against the seat surface of the second main valve seat 14.

In this example, reinforcing

pins

15c and 15d for shape retention are provided substantially at the center of the first U-shaped steering passage 16A of the first spool 15A and the second U-shaped steering passage 16B of the second spool 15B so as to extend in the front-rear direction (see also fig. 5).

In this example, recessed surfaces 15e are formed on the upper and lower surfaces of the main valve body 15 (the first spool 15A and the second spool 15B constituting the main valve body 15), and support plate portions 25c (with a slight gap in the left-right direction) of (

coupling plates

25A, 25B of) a coupling body 25 described later are fitted into the recessed surfaces 15 e.

As described above, in the main spool 15, the first spool 15A and the second spool 15B move in the direction of the axis O integrally with each other, so that the cooling position (upper end position) shown in fig. 1 and the heating position (lower end position) shown in fig. 2 can be selectively obtained, the cooling position is with port pF open and port pB and port pA in communication via a first U-shaped steering passage 16A of the first spool 15A, and a position where the port pE is opened and the port pC and the port pD are communicated via the second U-turn passage 16B of the second spool 15B, the heating position is to open the port pB and to communicate the port pA with the port pF via the first U-shaped steering passage 16A of the first spool 15A, and a position at which the port pC is opened and the port pD and the port pE are communicated via the second U-turn passage 16B of the second spool 15B.

The first spool 15A of the main spool 15 is located just above two of the three ports (port pB and port pA, or port pA and port pF) other than the outside during movement, and the second spool 15B of the main spool 15 is located just above two of the three ports (port pC and port pD, or port pD and port pE) other than the outside during movement, and at this time, the first spool 15A and the second spool 15B are pressed leftward and rightward and pressed against the seat surfaces of the first main valve seat 13 and the second main valve seat 14, respectively, by the pressure from the pressure chamber 17 (high-pressure refrigerant introduced into the pressure chamber 17) provided between the first spool 15A and the second spool 15B and the urging force of the compression coil spring 19.

The first piston 21 and the second piston 22 are connected to each other by a connecting body 25 so as to be movable integrally, and the first spool 15A and the second spool 15B of the main spool 15 are fitted and supported by the connecting body 25 in a state in which they are slidable slightly in the left-right direction and movement in the front-rear direction is substantially prevented.

In this example, the coupling body 25 is formed of a pair of plate members of the same size and the same shape, which are manufactured by press forming or the like, for example, and each of the plate members is arranged in the left-right direction (the direction orthogonal to the valve seat surfaces of the first main valve seat 13 and the second main valve seat 14) (in other words, parallel to the plane orthogonal to the valve seat surfaces), and the pair of plate members are arranged to face each other in the front-rear direction, and the main valve element 15 is sandwiched between the pair of plate members (in the front-rear direction). Hereinafter, the plate material disposed on the front side of main valve element 15 is referred to as a coupling plate 25A, and the plate material disposed on the rear side of main valve element 15 is referred to as a coupling plate 25B.

More specifically, as can be seen from fig. 1 and 2 and fig. 4 to 6, the connecting

plates

25A and 25B are each formed of a long rectangular plate material symmetrical with respect to a center line (symmetry line) extending in the front-rear direction from the center of the connecting

plates

25A and 25B. A support plate portion 25c having a shape (i.e., a substantially concave cross section) along the outer periphery (front surface and top and bottom surfaces or rear surface and top and bottom surfaces) of the main valve element 15 is formed at substantially the center (in the vertical direction) of each of the

coupling plates

25A and 25B so as to engage and support (a front portion or a rear portion of) the main valve element 15 so as to be movable integrally in the axis O direction. The width (in the left-right direction) of the support plate portion 25c is slightly smaller than the width of the recessed surface 15e provided on the upper and lower surfaces of the valve body 15.

A connecting plate portion 25A extending to a relatively narrow width (narrow width in the left-right direction) of the first piston 21 or the second piston 22 is connected to the upper and lower portions (along the axis O) of the support plate portion 25c of each connecting

plate

25A, 25B. Here, the connecting plate portion 25A of the front connecting plate 25A is disposed on the front side of the axis O, and particularly on the front side, when viewed in the left-right direction, avoids the six ports pA to pF opened in the seating surfaces of the first main valve seat 13 and the second main valve seat 14 (in other words, a position shifted forward from the six ports pA to pF), and the connecting plate portion 25A of the rear connecting plate 25B is disposed on the rear side of the axis O, particularly on the rear side, when viewed in the left-right direction, avoids the six ports pA to pF opened in the seating surfaces of the first main valve seat 13 and the second main valve seat 14 (in other words, a position shifted rearward from the six ports pA to pF). That is, in this example, when viewed in the left-right direction, the connecting plate portions 25A of the pair of connecting

plates

25A, 25B are disposed apart from the respective apertures (in the front-rear direction) of the ports pA to pF that open in the seat surfaces of the first main valve seat 13 and the second main valve seat 14, and the ports pA to pF (more specifically, the port pF and the port pE that are located on the lower side in the cooling position (upper end position) shown in fig. 1 and the port pB and the port pC that are located on the upper side in the heating position (lower end position) shown in fig. 2) are located between the connecting plate portions 25A of the pair of connecting

plates

25A, 25B (see fig. 4 in particular).

Further, mounting leg portions 25B are provided at upper and lower end portions of (the connecting plate portions 25A of) the

coupling plates

25A, 25B, the mounting leg portions 25B are formed so as to be bent substantially 90 ° toward the

coupling plates

25B, 25A disposed to face each other (the side opposite to the direction in which the support plate portions 25c having a substantially concave cross section are formed), insertion holes 29 are provided through the mounting leg portions 25B, and the insertion holes 29 are used for inserting bolts 30 for coupling the

coupling plates

25A, 25B to the first piston 21 or the second piston 22.

In this example, in consideration of the ease of assembly (described later), an uneven fitting portion 25d (see fig. 5 and 6 in particular) is formed at an end portion of the mounting leg portion 25B of each of the

coupling plates

25A and 25B, and the uneven fitting portion 25d is used to bring (positions in the left-right direction and the front-rear direction of) the

coupling plates

25A and 25B into contact with the

coupling plates

25B and 25A disposed to face each other and into alignment (that is, to bring the pair of

coupling plates

25A and 25B into alignment with each other).

In the illustrated example, the concave-convex fitting portions 25d of the connecting

plates

25A and 25B are formed as one concave-convex, but it is needless to say that, for example, as illustrated in fig. 7, a plurality of concave-convex fitting portions 25d (two in the example illustrated in fig. 7) may be formed.

In this example, since the

coupling plates

25A and 25B are each formed of plate materials having the same size and the same shape as described above, the two

coupling plates

25A and 25B are arranged to face each other in the front-rear direction and are combined in reverse (in detail, in a state of being aligned in opposite vertical directions) via the concave-convex fitting portion 25d, and the mounting leg portion 25B is fixed to the first piston 21 or the second piston 22 via the bolt 30. The first spool 15A and the second spool 15B of the main spool 15 are disposed (in the left-right direction) between the support plate portions 25c of the connecting

plates

25A, 25B (in a substantially rectangular space in side view), and the first spool 15A and the second spool 15B of the main spool 15 are fitted to the connecting body 25 in a state in which they are slightly slidable in the left-right direction and movement in the front-rear direction is substantially prevented (see fig. 5 in particular).

The main valve element 15 fitted and supported by (the pair of

coupling plates

25A, 25B of) the coupling body 25 is pushed by an upper portion or a lower portion (a rectangular plane having a wide width in the left-right direction) of a support plate portion 25c having a concave cross section of the

coupling plates

25A, 25B of the coupling body 25 (here, upper and lower surfaces of the first spool 15A and the second spool 15B of the main valve element 15 are pressed) in accordance with the reciprocating movement of the first and

second pistons

21, 22, and reciprocates between a cooling position (upper end position) and a heating position (lower end position).

[ operation of six-way valve body 10 ]

Next, the operation of the six-way valve body 10 having the above-described configuration will be described.

When the main valve 15 disposed in the main valve housing 11 is in the heating position (lower end position) (the second communication state shown in fig. 2), the second operating chamber 32 is communicated with the port pA, which is the discharge-side high-pressure port, and the first operating chamber 31 is communicated with the port pD, which is the suction-side low-pressure port, via the four-way pilot valve 90, which will be described later, high-temperature high-pressure refrigerant is introduced into the second operating chamber 32, and high-temperature high-pressure refrigerant is discharged from the first operating chamber 31. Therefore, the pressure of the second operating chamber 32 on the other end side (lower end side) of the main valve chamber 12 is higher than the pressure of the first operating chamber 31 on the one end side (upper end side) of the main valve chamber 12, and as shown in fig. 1, the first and

second pistons

21 and 22 and the main valve element 15 move upward, the first piston 21 abuts and is locked to the upper end cover member 11A, and the main valve element 15 is in the cooling position (upper end position) (the first communication state shown in fig. 1).

Thus, the port pA and the port pB are communicated with each other (via the first U-turn passage 16A), the port pC and the port pD (via the second U-turn passage 16B), and the port pE and the port pF (via the main valve chamber 12), so that the heat pump type cooling and heating system performs the cooling operation.

When the main valve 15 is at the cooling position (upper end position) (the first communication state shown in fig. 1), the first operating chamber 31 is communicated with the port pA, which is the discharge-side high-pressure port, and the second operating chamber 32 is communicated with the port pD, which is the suction-side low-pressure port, via the four-way pilot valve 90, which will be described later, high-temperature and high-pressure refrigerant is introduced into the first operating chamber 31, and high-temperature and high-pressure refrigerant is discharged from the second operating chamber 32. Therefore, the pressure of the first operating chamber 31 on one end side (upper end side) of the main valve chamber 12 is higher than the pressure of the second operating chamber 32 on the other end side (lower end side) of the main valve chamber 12, and as shown in fig. 2, the first and

second pistons

21 and 22 and the main valve element 15 move downward, the second piston 22 abuts and is locked to the lower end side cover member 11B, and the main valve element 15 is in the heating position (lower end position) (second communication state shown in fig. 2).

Thus, the port pA and the port pF are communicated with each other (via the first U-turn passage 16A), the port pE and the port pD are communicated with each other (via the second U-turn passage 16B), and the port pC and the port pB are communicated with each other (via the main valve chamber 12), so that the heat pump type cooling and heating system performs a heating operation.

[ Structure of four-way Pilot valve 90 ]

The four-way pilot valve 90 as a pilot valve is known in its own structure, and as shown in enlarged views in fig. 8(a) and (B), a valve housing 92 made of a cylindrical straight tube having an electromagnetic coil 91 fitted and fixed to the outside thereof is provided on the outer periphery of the base end side (left end side), and in the valve housing 92, a suction element 95, a compression coil spring 96, and a plunger 97 are arranged in series in this order from the base end side.

The left end portion of the valve housing 92 is hermetically joined to a flange-like portion (outer peripheral step portion) of the suction element 95 by welding or the like, and the suction element 95 is fastened and fixed to a cover 91A covering the outer periphery of the electromagnetic coil 91 for energization and excitation by a bolt 92B.

On the other hand, a cap member 98 with a filter having a narrow tube insertion port (high-pressure introduction port a) for introducing a high-pressure refrigerant is airtightly attached to the right end opening of the valve housing 92 by welding, brazing, caulking, or the like, and a region surrounded by the cap member 98, the plunger 97, and the valve housing 92 is a valve chamber 99. A high-temperature and high-pressure refrigerant is introduced into the valve chamber 99 from the port (discharge-side high-pressure port) pA via a flexible high-pressure tubule # a airtightly inserted into a tubule insertion port (high-pressure introduction port a) of the cap member 98.

Further, a valve seat 93 having a flat inner end surface is airtightly joined by brazing or the like between the plunger 97 and the cover member 98 in the valve housing 92, and in the valve seat surface (inner end surface) of the valve seat 93, a port b connected to the first operation chamber 31 of the six-way valve body 10 via a narrow tube # b, a port c connected to a port (suction-side low-pressure port) pD via a narrow tube # c, and a port d connected to the second operation chamber 32 via a narrow tube # d are opened in parallel laterally at predetermined intervals in the longitudinal direction (left-right direction) of the valve housing 92 in this order from the tip end side (right end side).

The plunger 97 disposed to face the suction element 95 is substantially cylindrical and is disposed slidably in the axial direction (direction along the center line L of the valve housing 92) in the valve housing 92. A valve element holder 94A is fixedly attached to an end portion of the plunger 97 on the side opposite to the suction element 95 by press fitting, caulking, or the like, with a base end portion thereof together with the attachment 94B, and the valve element holder 94A holds the valve element 94 slidably in the thickness direction on a free end side thereof. A plate spring 94C is attached to the valve body holder 94A, and the plate spring 94C biases the valve body 94 in a direction (thickness direction) in which the valve body 94 is pressed against the valve seat 93. The valve body 94 slides on the seat surface of the valve seat 93 in accordance with the movement of the plunger 97 in the lateral direction in a state of abutting against the seat surface of the valve seat 93 in order to switch the communication state among the ports b, c, and d that are opened on the seat surface of the valve seat 93.

The valve body 94 is provided with a recessed portion 94a, and the size of the recessed portion 94a is such that the adjacent ports b-c and c-d of the three ports b-d that open on the seat surface of the valve seat 93 can be selectively communicated with each other.

The compression coil spring 96 is attached to be compressed between the suction element 95 and the plunger 97 and biases the plunger 97 in a direction (rightward in the drawing) of separating from the suction element 95, and (a left end portion of) the valve seat 93 is a stopper that stops rightward movement of the plunger 97 in this example. As the structure of the stopper, it is needless to say that other structures can be adopted.

The four-way pilot valve 90 is attached to an appropriate position such as the back surface side of the six-way valve body 10 via a mounting tool 92A.

[ operation of the four-way pilot valve 90 ]

In the four-way pilot valve 90 configured as described above, when the electromagnetic coil 91 is not energized, the plunger 97 is pushed by the biasing force of the compression coil spring 96 until the right end thereof comes into contact with the valve seat 93, as shown in fig. 1 and 8 (a). In this state, the spool 94 is positioned above the port b and the port c, the port b and the port c communicate with each other through the recess 94a, and the port d and the valve chamber 99 communicate with each other, so that the high-pressure fluid flowing into the port (discharge-side high-pressure port) pA is introduced into the second operation chamber 32 via the high-pressure thin tube # a → the valve chamber 99 → the port d → the thin tube # d → the port p12, and the high-pressure fluid in the first operation chamber 31 flows and is discharged to the port p11 → the thin tube # b → the port b → the recess 94a → the port c → the thin tube # c → the port (suction-side low-pressure port) pD.

On the other hand, when the current to the electromagnetic coil 91 is turned on, as shown in fig. 2 and 8B, the plunger 97 is attracted by the attraction force of the attraction element 95 to a position where the left end thereof abuts against the attraction element 95 (against the urging force of the compression coil spring 96). At this time, the spool 94 is positioned on the port c and the port d, and the port c communicates with the port d and the port b communicates with the valve chamber 99 through the recessed portion 94a, so that the high-pressure fluid flowing into the port (discharge side high-pressure port) pA is introduced into the first operating chamber 31 via the high-pressure thin tube # a → the valve chamber 99 → the port b → the thin tube # b → the port p11, and the high-pressure fluid of the second operating chamber 32 flows into and is discharged from the port p12 → the thin tube # d → the port d → the recessed portion 94a → the port c → the thin tube # c → the port (suction side low-pressure port) pD.

Therefore, when the current to the solenoid 91 is turned off, the main valve element 15 of the six-way valve body 10 is shifted from the heating position (second communication state) to the cooling position (first communication state) to perform the flow path switching as described above, and when the current to the solenoid 91 is turned on, the main valve element 15 of the six-way valve body 10 is shifted from the cooling position (first communication state) to the heating position (second communication state) to perform the flow path switching as described above.

As described above, in the six-way switching valve 1 of the present embodiment, by switching the energization of the electromagnetic four-way pilot valve 90 on/off, the main valve element 15 constituting the six-way valve body 10 is moved in the main valve chamber 12 by the differential pressure between the high-pressure fluid (fluid flowing through the port pA which is a high-pressure portion) and the low-pressure fluid (fluid flowing through the port pD which is a low-pressure portion) flowing through the six-way switching valve 1, and the communication state between the six ports provided in the main valve housing 11 can be switched, and in the heat pump type cooling and heating system, switching from the heating operation to the cooling operation and switching from the cooling operation to the heating operation are performed.

[ Effect of six-way selector valve 1 ]

As is understood from the above description, in the six-way selector valve 1 of the present embodiment, the coupling body 25 for moving the main valve body 15 in accordance with the reciprocating movement of the first and

second pistons

21 and 22 is formed of plate members (

coupling plates

25A and 25B) arranged in the direction orthogonal to the seating surfaces of the first and second main valve seats 13 and 14, and the connecting plate portion 25A extending between the first and

second pistons

21 and 22 and the main valve body 15 is arranged at a position avoiding the ports pA to pF when viewed in the direction (left-right direction) orthogonal to the seating surfaces of the first and second main valve seats 13 and 14. Therefore, since the coupling body 25 can be manufactured by simple machining as compared with the conventional flow path switching valve described above, machining cost and machining man-hours can be suppressed, and the refrigerant in the main valve housing 11, particularly the refrigerant flowing into or out of the ports other than the port communicating with the main valve element 15, does not collide with the connecting plate portion 25a extending between the first and

second pistons

21 and 22 and the main valve element 15, so that the refrigerant smoothly flows in the main valve housing 11.

In the above-described conventional flow path switching valve (a structure in which a coupling body coupling the piston and the sliding main valve element is made of one plate material disposed to face the seat surface of the main valve seat), it is difficult to accurately press the end surface (upper and lower surfaces) of the main valve element 15 formed of two members (the first spool 15A and the second spool 15B), however, in the six-way selector valve 1 of the present embodiment, the end surface (upper and lower surfaces) of the main valve element 15 can be pressed by the upper and lower portions (rectangular flat surfaces having a wide width in the left-right direction) of the support plate portions 25c of the pair of

coupling plates

25A and 25B disposed to face each other in the front-rear direction, therefore, the positional deviation of the pressing position of the main valve element 15 due to the coupling body 25 can be suppressed, and the end face having the same width (width in the front-rear direction) can be accurately pressed against the main valve element 15.

In the present embodiment, the connecting member 25 is formed of a pair of plate members (connecting

plates

25A and 25B) having the same size and the same shape, and the dimensional error can be reduced.

Further, in the present embodiment, there is an advantage that the driving load and the Cv value are appropriately balanced by making the inner diameters of the body portion 11c of the main valve housing 11, the upper piston portion 11a, and the lower piston portion 11b different from each other.

< second embodiment >

Fig. 9 is a vertical cross-sectional view showing a six-way switching valve as a flow path switching valve according to a second embodiment of the present invention. In addition, the first and second substrates are,

fig. 10 is a cross-sectional view taken along line V-V of fig. 9.

The six-way switching valve 2 according to the second embodiment is different from the six-way switching valve 1 according to the first embodiment mainly in the configuration of a coupling body connecting the piston and the main valve body, and the other configurations are substantially the same. Accordingly, the portions corresponding to the respective portions of the six-way switching valve 1 are given common reference numerals, and redundant description is omitted, and the following description focuses on differences.

The six-way switching valve 2 of the illustrated embodiment is, for example, a slide-type configuration of the six-way switching valve used in the heat pump type air-cooling and heating system, as with the six-way switching valve 1 of the first embodiment, and in this example, the connecting plate portion 25A of (each of the connecting

plates

25A and 25B of) the connecting body 25 and the first and

second piston portions

11a and 11B are formed slightly shorter in the vertical direction (in the direction of the axis O) than the six-way switching valve 1 of the first embodiment.

Then, the upper connecting cover 11d of the main valve housing 11 (the outer peripheral portion of the first piston 11a) abuts (the upper end side corner portion of) the support plate portion 25c of (each of the connecting

plates

25A, 25B of) the connecting body 25 to serve as a stopper for preventing upward movement of the connecting body 25 (i.e., the main valve body 15 fitted to the connecting body 25), and the lower connecting cover 11e of the main valve housing 11 (the outer peripheral portion of the second piston 11B) abuts (the lower end side corner portion of) the support plate portion 25c of (each of the connecting

plates

25A, 25B of) the connecting body 25 to serve as a stopper for preventing downward movement of the connecting body 25 (i.e., the main valve body 15 fitted to the connecting body 25).

In other words, in the present embodiment, the stopper 25s that abuts against the upper connection cap 11d or the lower connection cap 11e of the main valve housing 11 to regulate the movement of the main valve element 15 in the vertical direction is provided in (the support plate portion 25c of each of the

connection plates

25A and 25B of) the connection body 25.

As described above, in the six-way selector valve 2 according to the second embodiment, since the stopper 25s for restricting the movement of the main valve element 15 is provided in the coupling body 25, not only are the same operational effects as those of the first embodiment described above obtained, but also the load applied to the first and

second pistons

21 and 22 can be reduced, and the dimensional accuracy of the components of the first and

second pistons

21 and 22 for restricting the position of the main valve element 15, the upper and lower end

side cover members

11A and 11B, and the like can be reduced, so that the manufacturing cost of the six-way selector valve 2 can be greatly reduced.

< third embodiment >

Fig. 11 is a vertical cross-sectional view showing a six-way switching valve as a flow path switching valve according to a third embodiment of the present invention. Fig. 12 is a cross-sectional view taken along the line of sight in fig. 11.

The six-way switching valve 3 according to the third embodiment is mainly different from the six-way switching valve 1 according to the first embodiment in the structure of a coupling body connecting the piston and the main valve body, and the other structures are substantially the same. Accordingly, the portions corresponding to the respective portions of the six-way switching valve 1 are given common reference numerals, and redundant description is omitted, and the following description focuses on differences.

In the six-way switching valve 1 of the first embodiment described above, the coupling body 25 is formed of a pair of plate members (

coupling plates

25A, 25B) having the same size and the same shape, but in the six-way switching valve 3 of the third embodiment shown in the drawing, the coupling body 25 is formed of one plate member (coupling plate 25C) of a vertically long rectangular shape disposed in the left-right direction (the direction orthogonal to the valve seating surfaces of the first main valve seat 13 and the second main valve seat 14) (in other words, in parallel to the plane orthogonal to the valve seating surfaces).

More specifically, in this example, as compared with the six-way switching valve 1 of the first embodiment, the depth (i.e., the length in the front-rear direction) of the support plate portion 25C having a concave cross section provided at the substantially center of the coupling body 25 (the coupling plate 25C) is increased to secure the engagement area with (the upper and lower surfaces of) the main valve body 15, and the connecting plate portions 25a provided above and below the support plate portion 25C extend to the first and

second pistons

21 and 22 through the rear sides of the ports pA to pF opened in the seating surfaces of the first main valve seat 13 and the second main valve seat 14 when viewed in the left-right direction.

In this case, the uneven fitting portion 25d of the connecting body 25 (connecting

plates

25A and 25B) of the six-way switching valve 1 according to the first embodiment can be omitted.

As described above, in the six-way selector valve 3 according to the third embodiment, since the connecting body 25 is formed of a single plate material (connecting plate 25C) produced by, for example, press forming, the same operational effects as those of the first embodiment can be obtained, and the number of parts, the number of assembly steps, and the like can be reduced.

< fourth embodiment >

Fig. 13 is a vertical cross-sectional view showing a sixth embodiment of a six-way switching valve as a flow path switching valve according to the present invention. Fig. 14 is a cross-sectional view taken along the Y-Y direction of fig. 13.

The six-way switching valve 4 of the fourth embodiment is different from the six-way switching valve 2 of the second embodiment mainly in the configuration of a coupling body connecting the piston and the main valve body, and the other configurations are substantially the same. Accordingly, the portions corresponding to the respective portions of the six-way switching valve 2 are given common reference numerals, and redundant description is omitted, and the following description focuses on differences.

In the six-way switching valve 4 of the fourth embodiment shown in the drawing, in comparison with the six-way switching valve 2 of the second embodiment described above, a part of the connecting plate portion 25A (of each connecting

plate

25A, 25B) of the connecting body 25 (in the example shown in the drawing, a portion close to the first piston 21 or the second piston 22 and a portion not overlapping with the ports pA to pF opened in the seating surfaces of the first main valve seat 13 and the second main valve seat 14) is bent and abutted on the opposite side of the connecting

plates

25B, 25A. That is, the connecting plate portion 25A of the pair of connecting

plates

25A, 25B constituting the connecting body 25 is provided with a butting plate portion 25e which butts against the connecting plate portion 25A of the opposite connecting

plate

25B, 25A.

In this example, the upper and lower end portions of (the connecting plate portion 25A of) the

coupling plates

25A and 25B are provided as mounting leg portions 25B bent toward the side opposite to the side of the

coupling plates

25B and 25A disposed to face each other (in the direction in which the support plate portion 25c having a substantially concave cross section is formed), and insertion holes 29 through which bolts 30 for coupling the

coupling plates

25A and 25B to the first piston 21 or the second piston 22 are inserted are provided in the mounting leg portions 25B.

plates

25A, 25B) of the six-way selector valves 1, 2 according to the first and second embodiments may be omitted.

As described above, in the six-way selector valve 4 according to the fourth embodiment, since a part of the pair of

coupling plates

25A and 25B disposed to face each other is butted against each other (the butting plate portion 25e is provided), the same operational effects as those of the second embodiment can be obtained, and there is an advantage that the strength of the coupling body 25 is improved and the weight is reduced.

In addition, although the six-way switching valves 1 to 4 of the first to fourth embodiments have been described by way of example in the heat pump type cooling and heating system, it is needless to say that the number and position of the ports provided in (the main valve chamber 12 of) the main valve housing 11, the structure and shape of the main valve body 15 disposed in (the main valve chamber 12 of) the main valve housing 11, and the like are not limited to the illustrated examples.

In the six-way switching valves 1 to 4 of the first to fourth embodiments, the description has been given of the configuration in which the main valve element 15 is driven in the main valve chamber 12 using the four-way pilot valve 90, but for example, a configuration in which a motor is used to drive the main valve element 15 in the main valve chamber 12 instead of the four-way pilot valve 90 is also possible.

The six-way switching valves 1 to 4 according to the first to fourth embodiments may be incorporated not only in the heat pump type cooling and heating system but also in other systems, devices, and facilities.

Claims

1. A flow path switching valve is provided with: a cylindrical main valve housing in which a piston and a main valve chamber are arranged; a main valve seat having a valve seat surface with a plurality of ports open; a sliding main valve element disposed in the main valve chamber so as to be movable in an axial direction and slidably abutting against the seat surface; and a connecting body for moving the main spool in accordance with the reciprocating movement of the piston, wherein the flow path switching valve switches between the ports communicating with the main spool by moving the main spool in the main valve chamber via the connecting body,

the connecting body is formed of one or more plate members arranged in a direction orthogonal to a valve seat surface of the main valve seat, and a connecting plate portion extending between the piston and the main valve body is arranged at a position avoiding the port when viewed in the direction orthogonal to the valve seat surface of the main valve seat.

2. The flow path switching valve according to claim 1,

the connecting plate portion is disposed at a position offset from the port in a direction perpendicular to the axis.

3. The flow path switching valve according to claim 1 or 2,

the plurality of ports are open on the opposite side with respect to the axis of the main valve housing, and the main valve body is configured such that a pair of slide valve bodies are arranged back to back in a direction orthogonal to the seat surface of the main valve seat.

4. The flow path switching valve according to claim 1 or 2,

the coupling body is provided with a stopper for restricting the movement of the main valve element.

5. The flow path switching valve according to claim 4,

the stopper abuts against the main valve housing.

6. The flow path switching valve according to claim 1 or 2,

the connecting body is composed of a pair of plate materials which are reversely arranged and have the same size and the same shape.

7. The flow path switching valve according to claim 6,

the pair of plate materials is provided with a concave-convex fitting portion for aligning the pair of plate materials with each other.

8. The flow path switching valve according to claim 6,

a portion of the pair of sheets butt against each other.

9. The flow path switching valve according to claim 7,

a portion of the pair of sheets butt against each other.

10. The flow path switching valve according to claim 1 or 2,

the connecting body is formed by a sheet of plate material.

11. The flow path switching valve according to claim 1 or 2,

the connecting body has: a support plate portion that is slidably supported by fitting the main valve element in a direction orthogonal to a seat surface of the main valve seat, and that is integrally movable in an axial direction with the main valve element; and the web portion extending from the support plate portion to the piston.

12. The flow path switching valve according to claim 1 or 2,

the main valve housing has a piston portion in which the piston is disposed and a barrel portion in which the main spool is disposed, and the piston portion and the barrel portion have different inner diameters.