CN109578617B - Flow path switching valve - Google Patents

Abstract

The invention provides a flow path switching valve which is difficult to cause valve leakage and can effectively restrain pressure loss. The coupling body 25 is formed of one or more plate materials having a pair of support plate portions (25A) which are disposed parallel to the seat surfaces of the main valve seats (the first main valve seat (13) and the second main valve seat (14)) and are separated in a direction (height direction of the seat surfaces) orthogonal to the seat surfaces of the main valve seats (the first main valve seat (13) and the second main valve seat (14)), and the pair of first and second slide valve bodies (15A, 15B) are respectively coupled, fitted, or engaged with the pair of support plate portions (25A) so as to move in accordance with the reciprocating movement of the pistons (21, 22).

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 cooling and heating system such as a room air conditioner or a car air conditioner includes a flow path switching valve as a flow path (flow direction) switching means in addition to a compressor, an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and the like.

As such a flow path switching valve, a four-way switching valve is known, but a six-way switching valve may be used instead.

An example of a heat pump type cooling and heating system including a six-way switching valve will be briefly described below with reference to fig. 7(a) and (B). The heat pump type cooling/heating system 100 illustrated in the figure switches the operation modes (cooling operation and heating operation) by the six-way switching valve 180, and basically includes: the compressor 110, the outdoor heat exchanger 120, the indoor heat exchanger 130, the expansion valve 150 for cooling, and the expansion valve 160 for heating are disposed with a six-way switching valve 180 having six ports pA, pB, pC, pD, pE, and pF therebetween.

When the cooling operation mode is selected, as shown in fig. 7(a), the high-temperature and high-pressure refrigerant discharged from the compressor 110 is introduced from the port pA of the six-way switching valve 180 into the outdoor heat exchanger 120 via the port pB, exchanges heat with outdoor air, condenses therein, and is introduced into the expansion valve 150 for cooling as a high-pressure two-phase gas-liquid or liquid-phase refrigerant. The high-pressure refrigerant is decompressed by the expansion valve 150 for cooling, the decompressed low-pressure refrigerant is introduced from the port pE of the six-way switching valve 180 into the indoor heat exchanger 130 via the port pF, and is subjected to heat exchange (cooling) with the indoor air and evaporated therein, and the low-temperature low-pressure refrigerant from the indoor heat exchanger 130 is returned from the port pC of the six-way switching valve 180 to the intake side of the compressor 110 via the port pD.

On the other hand, when the heating operation mode is selected, as shown in fig. 7B, the high-temperature and high-pressure refrigerant discharged from the compressor 110 is introduced from the port pA of the six-way switching valve 180 into the indoor heat exchanger 130 via the port pF, and is condensed by exchanging heat (heating) with the indoor air, and is introduced into the heating expansion valve 160 as a high-pressure two-phase gas-liquid or liquid-phase refrigerant. The high-pressure refrigerant is decompressed by the heating expansion valve 160, the decompressed low-pressure refrigerant is introduced from the port pC of the six-way switching valve 180 into the outdoor heat exchanger 120 through the port pB, and is evaporated by exchanging heat with the outdoor air, and the low-temperature low-pressure refrigerant from the outdoor heat exchanger 120 returns from the port pE of the six-way switching valve 180 to the intake side of the compressor 110 through the port pD.

As a six-way switching valve (flow path switching valve) incorporated in the heat pump type cooling/heating system described above, 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 the sliding main valve element is disposed to be slidable in the left-right direction while the ports pA to pF are provided in the main valve housing. 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 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.

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

The conventional flow path switching valve as described above has the following problems to be solved.

That is, in the six-way switching valve (flow path switching valve) of the sliding type disclosed in patent document 1, since five ports pB to pF of the six ports pA to pF are provided in parallel in the axial direction, the main valve seat and the sliding type main valve body provided with the five ports pB to pF become long (in the axial direction), and it is difficult to ensure surface accuracy (flatness) of the seat surface of the main valve seat and the seal surface of the sliding type main valve body which slidably abut against the sliding type main valve body, and there is a possibility that initial leakage and leakage (valve leakage) due to durability deterioration increase.

In addition, in the main valve housing having a small inner volume, the high-pressure fluid (refrigerant) collides with the inner wall surface and the like, and the flow direction thereof largely changes in a crank shape, so that there is a problem that the pressure loss increases.

In addition to the above, in the conventional flow path switching valve, particularly in the flow path switching valve used in the heat pump type cooling and heating system, a high-temperature and high-pressure refrigerant (a refrigerant flowing from the port pA to the port pB and from the port pA to the port pF) and a low-temperature and low-pressure refrigerant (a refrigerant flowing from the port pC to the port pD and from the port pE to the port pD) flow in close proximity in the main valve housing. Specifically, a high-temperature high-pressure refrigerant and a low-temperature low-pressure refrigerant flow through the main valve seat to the adjacent port pB and port pC during cooling operation and flow through the main valve seat to the adjacent port pF and port pC during heating operation, but the main valve seat provided with each port is generally made of a metal having high thermal conductivity, and therefore the amount of heat exchange (i.e., heat loss) therebetween increases, and there is a problem that the system efficiency deteriorates.

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 which can effectively suppress pressure loss while preventing valve leakage.

Another object of the present invention is to provide a flow path switching valve that can reduce heat loss and improve the efficiency of a heat pump type cooling and heating system when used in an environment where a high-temperature high-pressure fluid and a low-temperature low-pressure fluid flow, such as a heat pump type cooling and heating system.

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 provided with a piston and a main valve chamber; a main valve seat having a valve seat surface with a plurality of ports open; a sliding main valve body disposed in the main valve chamber so as to be movable in an axial direction and slidably abutting against the seat surface; and a coupling body for moving the main spool in accordance with the reciprocating movement of the piston, the flow path switching valve switching the main spool in the main valve chamber via the coupling body to switch between the ports that communicate with each other, the flow path switching valve being characterized in that a plurality of ports are opened on the opposite side with respect to an axis of the main valve housing, and the main spool is configured such that a pair of slide spools are arranged in a state of being aligned on the back surface in a direction orthogonal to the seat surface of the main valve seat, a U-shaped turning passage selectively allowing communication between the plurality of ports is provided in each of the pair of slide spools, the coupling body is configured by one or a plurality of plate members having a pair of support plate portions that are arranged in parallel with the seat surface of the main valve seat and are separated from each other in a direction orthogonal to the seat surface of the main valve seat, the pair of slide valve elements are coupled, fitted or engaged with the pair of support plate portions, respectively, to move in accordance with the reciprocating movement of the piston.

In a preferred aspect, the pair of support plate portions are each formed with an opening, and the pair of slide valves are each pushed by the opening so as to be integrally movable in the axial direction in accordance with the reciprocating movement of the piston, and are each slidably fitted in the opening in a direction orthogonal to the seat surface of the main valve seat.

In another preferred aspect, the pair of support plate portions are coupled to, fitted to, or engaged with the pair of slide valves at portions of the pair of slide valves close to the valve seat surfaces, respectively.

In another preferred aspect, a separate opening is formed in a connecting plate portion of the connecting body extending between the support plate portion and the piston.

In another preferred aspect, the connecting body is formed of a pair of plate members having the same size and the same shape, each plate member having the support plate portion and being disposed in an opposite direction.

In another preferred mode, the pair of plate materials is provided with an abutting step portion for aligning the pair of plate materials with each other in position.

In another preferred aspect, the connecting body is formed of one plate member having the pair of support plate portions.

Effects of the invention

In the six-way selector valve of the present invention, a plurality of ports are opened on the opposite side of the main valve housing from the axis, the main valve body is configured such that a pair of slide valve bodies, each provided with a U-shaped turning passage for selectively communicating the plurality of ports, are arranged in a state of back alignment in the direction orthogonal to the seat surface of the main valve seat, and the main valve body is moved in the main valve chamber so that the communicated ports are switched. Therefore, compared to a flow path switching valve using a conventional sliding main valve element, the main valve seat provided with a port and the main valve element can be shortened (in the axial direction), and therefore, it is easy to ensure the surface accuracy (flatness) of the seat surface of the main valve seat and the sealing surface of the main valve element, and to suppress valve leakage, and fluid (for example, high-pressure fluid (refrigerant)) flows through the U-turn passage, and therefore, pressure loss can be reduced.

In addition to the above, when the flow path switching valve according to the present embodiment is used in an environment where a high-temperature high-pressure refrigerant and a low-temperature low-pressure refrigerant flow, such as a heat pump type cooling and heating system, the U-turn passage through which the high-temperature high-pressure refrigerant flows and the U-turn passage through which the low-temperature low-pressure refrigerant flows are provided to be separated far from each other without passing through a main valve seat made of metal, for example, and therefore, compared to a conventional configuration in which the high-temperature high-pressure refrigerant and the low-temperature low-pressure refrigerant flow in a state of being close to each other through a main valve seat made of metal, the amount of heat exchange therebetween (i.e., heat loss) can be significantly reduced, and therefore, the effect of improving the efficiency of the system can also be obtained.

In the flow path switching valve of the present embodiment, the coupling body includes a pair of support plate portions that are disposed parallel to the seat surface of the main valve seat and are separated in a direction orthogonal to the seat surface of the main valve seat (the height direction of the seat surface), and the pair of first and second slide valves are coupled, fitted, or engaged with the pair of support plate portions so as to move in accordance with the reciprocating movement of the piston. Therefore, compared to a conventional flow path switching valve in which, for example, the coupling body is formed of a single plate material arranged parallel to the valve seat surface of the main valve seat, the main valve body (specifically, each of the slide valve bodies forming the main valve body) can be pressed at a position close to the valve seat surface, and tilting of the main valve body can be suppressed to move (slide) smoothly.

In the flow path switching valve of the present embodiment, the slide valve bodies constituting the main valve body are supported by the support plate portions so as to be movable up and down with respect to the seat surface, and therefore, there is an advantage that the sealing performance is easily ensured.

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 a cross-sectional view taken along the line U-U arrow of fig. 1.

Fig. 4 is an enlarged longitudinal sectional view of a main portion of the six-way switching valve shown in fig. 1.

Fig. 5 is a diagram showing a pair of connecting plates constituting a connecting body according to an embodiment of the flow path switching valve (six-way switching valve) of the present invention, wherein (a) is a vertical sectional view, (B) is a side view, and (C) is a plan view.

Fig. 6 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 energization is turned off), and (B) is a vertical sectional view showing a second communication state (during heating operation) (when energization is turned on).

Fig. 7 is a schematic configuration diagram of an example of a heat pump type cooling/heating system using a six-way switching valve as a flow path switching valve, where (a) is a schematic configuration diagram showing a cooling operation, and (B) is a schematic configuration diagram showing a heating operation.

Description of the symbols

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

10 six-way valve body

11 main valve casing

11A upper end side cover part

11B lower end side cover part

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

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

21 first piston

22 second piston

25 connected body

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

25a support plate part

25b connecting plate part

25c mounting foot

25d rectangular opening

25e circular opening

25f butt-joint step part

31 first action chamber

32 second motion chamber

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.

Fig. 1 and 2 are vertical sectional views showing an embodiment of a six-way switching valve as a flow path switching valve according to the present invention, fig. 1 is a view showing a first communication state (during a cooling operation), and fig. 2 is a view showing a second communication state (during a heating operation). Fig. 3 is a cross-sectional view taken along the line U-U arrow of fig. 1.

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 the six-way switching valve 180 in the heat pump type cooling and heating system 100 shown in fig. 7(a) and (B), for example, 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 of the present embodiment are denoted by the same reference numerals as those of the ports pA to pF of the six-way switching valve 180.

[ 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 packing 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.

An umbrella-shaped upper-end-side cover member 11A serving as a stopper is airtightly fixed to the upper end of the main valve housing 11, the upper-end-side cover member 11A prevents upward movement of the first piston 21 defining the variable-capacity first operating chamber 31, an inverted-umbrella-shaped lower-end-side cover member 11B serving as a stopper is airtightly fixed to the lower end of the main valve housing 11, and the lower-end-side cover member 11B prevents downward movement of the second piston 22 defining 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 attached to the upper end-side cover member 11A and the lower end-side cover member 11B, respectively.

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

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 main valve housing 11 at the left center of the main valve chamber 12 by brazing or the like, and three ports (port pB, port pA, and port pF in order from the upper end) formed of pipe joints extending leftward are vertically aligned (aligned in the direction of the axis O) at substantially equal intervals on the seat surface of the first main valve seat 13.

Further, at the center of the right portion 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 main valve housing 11 by brazing or the like, and three ports (port pC, port pD, port pE in order from the upper end side) formed of pipe joints extending rightward are vertically aligned (aligned in the axis O direction) and opened at substantially equal intervals at the seat surface of the second main valve seat 14.

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, 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.

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 cylindrical fitting convex portion 15A slightly smaller than the outer shape of the first spool 15A (in other words, the outer shape of the second spool 15B) protrudes 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 being interposed between the fitting convex portion 15A and the cylindrical portion 15B), the first slide valve body 15A and the second slide valve body 15B are slightly movable in the left-right direction (the direction perpendicular to the axis O, and the direction in which the ports (the port pB, the port pA, the port pF) provided in the first main valve seat 13 and the ports (the port pC, the port pD, the port pE) provided in the second main valve seat 14 face each other), 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 (specifically, in an annular groove provided in the outer periphery of the fitting convex portion 15A).

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 to 3 and 4, 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 of a left direction pressure received by (a right surface of) the first spool 15A 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 of (a left surface of) the first spool 15A due to the high-pressure refrigerant flowing through the port (inside the annular seal surface) receiving the right direction pressure.

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, 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.

In this example, recessed surfaces 15e are formed on the outer peripheral surfaces (upper and lower surfaces and front and rear surfaces) of the main valve body 15 (the first spool 15A and the second spool 15B constituting the main valve body 15), and the recessed surfaces 15e are fitted into (upper and lower end edges of) rectangular openings 25d of connecting plates 25A and 25B of a connecting body 25 to be described later.

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 slide 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 slide 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 slide spool 15A and the second slide spool 15B are pressed to the left and right by the pressure from the pressure chamber 17 (high-pressure refrigerant introduced into the pressure chamber 17) provided between the first slide spool 15A and the second slide spool 15B and the urging force of the compression coil spring 19, and are pressed against the valve seat surfaces of the first main valve seat 13 and the second main valve seat 14, respectively.

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 and the up-down direction is substantially prevented.

In this example, the connecting member 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 disposed so as to be orthogonal to the left-right direction (in other words, so as to be parallel to the valve seat surfaces of the first main valve seat 13 and the second main valve seat 14), and the pair of plate members are disposed so as to be separated from each other and opposed to each other in the left-right direction (the direction orthogonal to the valve seat surfaces). Hereinafter, the plate material disposed on the left side (the first spool 15A side) is referred to as a connecting plate 25A, and the plate material disposed on the right side (the second spool 15B side) is referred to as a connecting plate 25B.

More specifically, as can be seen from fig. 1 to 3 and 5, each of the connecting plates 25A and 25B is formed of a long rectangular plate material symmetrical with respect to a center line (symmetry line) extending in the left-right direction from the center of each of the connecting plates 25A and 25B. A central portion (in the vertical direction) of each of the connecting plates 25A and 25B is defined as a support plate portion 25A, the support plate portion 25A is configured to engage and support (the first spool 15A and the second spool 15B of) the main spool 15 so as to be movable in the axis O direction integrally therewith, a rectangular opening 25d having, for example, an arc-shaped corner portion (a band R) is formed in the support plate portion 25A (i.e., the central portion of the connecting plates 25A and 25B), and the first spool 15A and the second spool 15B of the main spool 15 are slidably fitted in the rectangular opening 25d from the left and right sides. The first and second spools 15A, 15B of the main spool 15 are partially pushed by the rectangular openings 25d of the connecting plates 25A, 25B of the connecting body 25 in accordance with the reciprocating movement of the first and second pistons 21, 22, and reciprocate between a cooling position (upper end position) and a heating position (lower end position). In this example, (the support plate portion 25A of) each of the coupling plates 25A and 25B is disposed apart (in the left-right direction) so that the rectangular opening 25d portion of each of the coupling plates 25A and 25B pushes the portions of the first main valve seat 13 and the second main valve seat 14 of the first spool 15A and the second spool 15B of the main valve element 15, which portions are close to the valve seat surface.

The upper and lower portions of the support plate portion 25A in each of the connecting plates 25A and 25B are provided as a connecting plate portion 25B extending up to the first piston 21 or the second piston 22, and a circular opening 25e (having substantially the same diameter as the ports pF and pE) is formed in a portion of the connecting plate portion 25B (in other words, the upper and lower portions of the rectangular opening 25 d) located on the lower side of the first main valve seat 13 and substantially a front side surface of the port pE located on the lower side of the second main valve seat 14 when the main valve spool 15 is at the cooling position (upper end position), and a circular opening 25e (having substantially the same diameter as the ports pB and pC) is formed in a portion of the port pB located on the upper side of the first main valve seat 13 and substantially a front side surface of the port pC located on the upper side of the second main valve seat 14 when the main valve spool 15 is at the heating position (lower end position).

Further, mounting leg portions 25C are provided at upper and lower end portions of (the connecting plate portions 25B of) the coupling plates 25A, 25B, the mounting leg portions 25C are formed to be bent substantially 90 ° toward the coupling plates 25B, 25A disposed to face each other, and screw holes 29 (see fig. 5C in particular) for inserting bolts 30 for coupling the coupling plates 25A, 25B to the first piston 21 or the second piston 22 are screwed into the mounting leg portions 25C.

In this example, in consideration of the ease of assembly (described later), an abutting step portion 25f (see fig. 5(C), in particular) is formed at the end of the mounting leg portion 25C of each of the coupling plates 25A, 25B, and the abutting step portion 25f is used to abut (position in the left-right direction and the front-rear direction of) the coupling plates 25A, 25B against the coupling plates 25B, 25A disposed to face each other and align the positions (that is, to align the pair of coupling plates 25A, 25B with each other).

In this example, since the coupling plates 25A and 25B are each formed of a plate material 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 left-right direction and are combined in reverse (in detail, in a state of being aligned in the vertical direction) via the abutment step portion 25f, and the first spool 15A and the second spool 15B of the main spool 15 are arranged in the rectangular opening 25d (from the left-right direction, respectively) of the support plate portion 25A of the coupling plates 25A and 25B. The mounting leg portions 25c are fixed to the first piston 21 or the second piston 22 via bolts 30, and the first spool 15A and the second spool 15B of the main spool 15 are fitted to the coupling 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.

The main valve element 15 fitted and supported by (the pair of connecting plates 25A, 25B of) the connecting body 25 is pushed by the upper end edge portion or the lower end edge portion of the rectangular opening 25d in the connecting plates 25A, 25B of the connecting body 25 (here, the 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 the cooling position (upper end position) and the 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 100 performs a cooling operation as shown in fig. 7(a) and (B).

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 100 performs a heating operation as shown in fig. 7(a) and (B).

[ 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. 6(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. In the four-way pilot valve 90, the port pD, which is the suction-side low-pressure port, is connected to the narrow tube # c, but the port pC through which the medium-pressure refrigerant flows may be connected to the narrow tube # c.

[ 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 6 (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 fig. 6B, 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 as shown in fig. 7(a) and (B), in the heat pump type cooling and heating system 100, switching from the heating operation to the cooling operation and switching from the cooling operation to the heating operation are performed.

[ Effect of operation of six-way selector valve (channel selector valve) 1 ]

As can be understood from the above description, in the six-way switching valve 1 of the present embodiment, the port pB, the port pA, and the port pF are opened side by side in the axis O direction in the main valve chamber 12, the port pC, the port pD, and the port pE are opened side by side in the axis O direction on the opposite side of the port pB, the port pA, and the port pF with respect to the axis O, the main valve body 15 is configured such that a pair of first and second slide valve bodies 15A, 15B are arranged in a state of being aligned on the back side in the direction orthogonal to the seat surface of the main valve seat (the first main valve seat 13 and the second main valve seat 14), the pair of first and second slide valve bodies 15A, 15B are respectively provided with first and second U-shaped turning passages 16A, 16B that selectively communicate the three ports (the port pB, the port pA, the port pF, and the port pC, the main valve seat 14), the port pD, and the main valve body 15 is moved in the chamber 12, thereby switching between the communicating ports. Therefore, compared to a flow path switching valve using a conventional sliding main valve, the main valve seats (the first main valve seat 13 and the 2 nd main valve seat 14) provided with ports and the main valve 15 (in the axis O direction) can be made shorter, so that the surface accuracy (flatness) of the seat surfaces of the main valve seats (the first main valve seat 13 and the second main valve seat 14) and the seal surfaces of the main valve 15 is easily ensured, valve leakage is suppressed, and fluid (for example, high-pressure fluid (refrigerant)) flows through the first U-turn passage 16A, and therefore, pressure loss can be reduced.

In addition, in the present embodiment, since the fluid (for example, low-pressure refrigerant) flowing in the six-way valve body 10 flows through the second U-turn passage 16B and the fluid (for example, medium-pressure refrigerant) flows in the left-right direction (linearly) in the main valve chamber 12, the pressure loss can be reduced.

In addition to the above, when the six-way switching valve 1 of the present embodiment is used in an environment where a high-temperature and high-pressure refrigerant and a low-temperature and low-pressure refrigerant flow, such as a heat pump type cooling and heating system, the first U-shaped turning passage 16A through which the high-temperature and high-pressure refrigerant flows and the second U-shaped turning passage 16B through which the low-temperature and low-pressure refrigerant flows are provided to be separated far apart from each other without passing through a metal main valve seat, for example, and therefore, compared to a conventional configuration in which the high-temperature and high-pressure refrigerant and the low-temperature and low-pressure refrigerant flow in a close state through a metal main valve seat, the amount of heat exchange therebetween (i.e., heat loss) can be significantly reduced, and therefore, the effect of improving the efficiency of the system can also be obtained.

In the six-way switching valve 1 of the present embodiment, the coupling body 25 includes a pair of support plate portions 25A arranged parallel to the seating surfaces of the main valve seats (the first main valve seat 13 and the 2 nd main valve seat 14) and separated in a direction (a height direction of the seating surfaces) orthogonal to the seating surfaces of the main valve seats (the first main valve seat 13 and the second main valve seat 14), and the pair of first and second slide valve bodies 15A and 15B are respectively coupled, fitted, or engaged with the pair of support plate portions 25A so as to move in accordance with the reciprocating movement of the pistons 21 and 22. Therefore, as compared with a conventional flow path switching valve in which, for example, a coupling body is formed of a single plate material arranged in parallel with the valve seat surface of the main valve seat, main valve body 15 (specifically, first and second slide valve bodies 15A and 15B forming main valve body 15) can be pressed at a position close to the valve seat surface, and tilting of main valve body 15 can be suppressed to smoothly move (slide), whereby valve leakage can be suppressed, and sliding resistance can be suppressed to improve operability.

In the six-way switching valve 1 of the present embodiment, the first and second spool valves 15A and 15B constituting the main spool 15 are supported by the support plate sections 25A so as to be movable up and down with respect to the seat surface, and therefore, there is an advantage that sealing performance is easily ensured.

In the above-described embodiment, the six-way selector valve in which the total of six ports pA to pF are three opened on the opposite side of the main valve housing 11 from the axis O has been described as an example, but the number and position of the ports provided in (the main valve chamber 12 of) the main valve housing 11, the configuration and shape of the main valve housing 11, and the configuration and shape of the main valve body 15 disposed in (the main valve chamber 12 of) the main valve housing 11 are not limited to the illustrated example.

In the above embodiment, the example in which the connecting body 25 is constituted by the pair of plate materials having the same size and the same shape and each having the support plate portion 25a with the rectangular opening 25d has been described, but the connecting body 25 may be formed by, for example, bending one plate material and arranging the pair of support plate portions 25a facing each other while being separated in the left-right direction. In the above embodiment, the connecting plate sections 25B of the connecting plates 25A and 25B constituting the connecting body 25 are disposed apart from the support plate sections 25A (in the left-right direction), and it is needless to say that a part or all of the connecting plate sections 25B of the connecting plates 25A and 25B may be deformed to abut each other in a direction in which they approach each other.

In the six-way switching valve 1 of the above embodiment, the configuration in which the main valve element 15 is driven in the main valve chamber 12 using the four-way pilot valve 90 has been described, but, for example, a configuration in which the main valve element 15 is driven in the main valve chamber 12 using a motor may be employed instead of the four-way pilot valve 90.

In addition, the six-way switching valve 1 according to the above embodiment can be incorporated not only in the heat pump type cooling and heating system, but also in other systems, devices, and facilities.

Claims (7)

1. A flow path switching valve is provided with: a cylindrical main valve housing provided with a piston and a main valve chamber; a main valve seat having a valve seat surface with a plurality of ports open; a sliding main valve body 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 element in accordance with the reciprocation of the piston, wherein the flow path switching valve switches between the ports communicating with each other by moving the valve element in the main valve chamber via the connecting body,

a plurality of ports open on the opposite side with respect to the axis of the main valve housing, and the main spool is configured as a pair of slide spools arranged in a state of back-surface alignment in a direction orthogonal to the seat surface of the main valve seat, and a U-shaped steering passage selectively communicating between the plurality of ports is provided in each of the pair of slide spools,

the coupling body is formed of one or more plate members having a pair of support plate portions that are disposed parallel to the seat surface of the main valve seat and are separated from each other in a direction orthogonal to the seat surface of the main valve seat, and the pair of slide valves are coupled, fitted, or engaged with the pair of support plate portions, respectively, so as to move in accordance with the reciprocating movement of the piston.

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

an opening is formed in each of the pair of support plate portions, and each of the pair of slide valve bodies is pushed by the opening so as to be integrally movable in the axial direction in accordance with the reciprocating movement of the piston, and is fitted to the opening so as to be slidable in a direction orthogonal to the seat surface of the main valve seat.

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

the pair of support plate portions are coupled to, fitted into, or engaged with the pair of slide valves at portions of the pair of slide valves close to the valve seat surfaces, respectively.

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

an additional opening is formed in a connecting plate portion of the connecting body extending between the support plate portion and the piston.

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

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

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

the pair of plates are provided with abutting stepped portions for aligning the pair of plates with each other.

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

the connecting body is formed of a single plate member having the pair of support plate portions.

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