JP6461589B2 - Flow path switching valve - Google Patents

Description

  The present invention relates to a slide-type flow path switching valve that performs flow path switching by moving a valve body, and more particularly to a flow path switching valve that is suitable for performing flow path switching in a heat pump air conditioning system or the like.

  Generally, a heat pump type air conditioning system such as a room air conditioner or a car air conditioner has 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. It has.

  An example of a heat pump type air conditioning system equipped with this flow path switching valve will be briefly described with reference to FIG. The heat pump type air conditioning system 100 in the illustrated example is configured such that the operation mode (cooling operation and heating operation) is switched by the flow path switching valve (four-way switching valve) 140. Basically, the compressor 110, the outdoor A heat exchanger 120, an indoor heat exchanger 130, and an expansion valve 160; four ports between the compressor 110, the outdoor heat exchanger 120, the indoor heat exchanger 130, and the expansion valve 160; That is, a flow path switching valve 140 having a discharge side high pressure port D, an outdoor side input / output port C, an indoor side input / output port E, and a suction side low pressure port S is arranged.

  The devices are connected by a flow path formed by a conduit (pipe) or the like, and when the cooling operation mode is selected, as shown by a solid line arrow in FIG. The high pressure port D is connected to the outdoor side input / output port C, and the indoor side input / output port E is connected to the suction side low pressure port S. As a result, the refrigerant is sucked into the compressor 110, and the high-temperature and high-pressure refrigerant is led from the compressor 110 to the outdoor heat exchanger 120 through the flow path switching valve 140, where it is condensed by exchanging heat with outdoor air. The high-pressure two-phase refrigerant is introduced into the expansion valve 160. The high-pressure refrigerant is decompressed by the expansion valve 160, and the decompressed low-pressure refrigerant is introduced into the indoor heat exchanger 130, where it heats (cools) and evaporates with the indoor air, and evaporates from the indoor heat exchanger 130. The low-temperature and low-pressure refrigerant is returned to the suction side of the compressor 110 through the flow path switching valve 140.

  On the other hand, when the heating operation mode is selected, the discharge side high-pressure port D of the flow path switching valve 140 is set to the indoor side input / output port E and the outdoor side input / output port C is set as shown by the broken line arrow in FIG. The high-pressure and high-pressure refrigerant is communicated to the suction-side low-pressure port S from the compressor 110 to the indoor heat exchanger 130 where it is condensed by heat exchange (heating) with room air. And introduced into the expansion valve 160. The expansion valve 160 decompresses the high-pressure refrigerant, and the decompressed low-pressure refrigerant is introduced into the outdoor heat exchanger 120 where it evaporates by exchanging heat with the outdoor air, and the outdoor heat exchanger 120 generates a low-temperature and low-pressure refrigerant. The refrigerant is returned to the suction side of the compressor 110 through the flow path switching valve 140.

  2. Description of the Related Art Conventionally, as a four-way switching valve incorporated in a heat pump type air conditioning system as described above, a valve having a valve body (main valve housing) incorporating a slide type main valve body and an electromagnetic pilot valve is known. (For example, refer to Patent Document 1). In the slide type flow path switching valve described in Patent Document 1, a discharge side high pressure port D, an outdoor side inlet / outlet port C, a suction side low pressure port S, and an indoor side inlet / outlet port E are formed in a main valve housing. At the same time, the slide type main valve body is arranged to be slidable in the left-right direction so as to create a communication state of ports D → C and E → S or ports D → E and C → S (switching the flow path). Be present. The high pressure refrigerant on the discharge side of the compressor and the low pressure refrigerant on the suction side of the compressor are selectively introduced to the left and right of the slide type main valve body in the main valve housing, respectively, via a pilot valve. Two working chambers defined by a pair of right and left pistons with packing are provided, and the flow is achieved by sliding the sliding main valve body in the left-right direction using the pressure difference between the two working chambers. The path is switched.

JP 2009-41636 A

  In the conventional slide type flow path switching valve as described above, the high-pressure fluid (refrigerant) collides with the inner wall surface and the like in the main valve housing having a relatively small internal volume, and the flow direction changes greatly. There is a dislike to increase the loss, and since it is configured to switch the flow path by sliding a slide type main valve body with a pair of left and right packing pistons, the sliding part is easily worn by stick slip etc. Along with this, the durability and the sealing performance of the sliding part are deteriorated, and there is a problem that the fluid (refrigerant) easily leaks from the sliding surface between the main valve housing and the sliding type main valve body (the valve leaks easily). .

  In addition to the above, in a conventional flow path switching valve, in particular, a four-way switching valve used in the heat pump type air conditioning system described above, a high-temperature high-pressure refrigerant and a low-temperature low-pressure refrigerant are in close proximity (thin wall) in the main valve housing. Therefore, there is also a problem that the heat exchange amount in the main valve housing becomes large and the efficiency of the system is deteriorated.

  The present invention has been made in view of the above circumstances. The object of the present invention is to reduce pressure loss and reduce the amount of internal heat exchange as much as possible, and to effectively wear the sliding portion. It is an object of the present invention to provide a flow path switching valve that can be suppressed effectively, can improve durability and sealing performance, and can prevent valve leakage.

In order to achieve the above object, the flow path switching valve according to the present invention basically has a rectangular tube shape in which the upper surface opening and the lower surface opening are hermetically sealed by the upper valve seat and the lower valve seat. A main valve having a main valve housing, a port provided in total at least three in the upper valve seat and / or the lower valve seat, and a main valve body movably disposed in the main valve housing; A fluid pressure type actuator for moving the main valve body, and a plurality of communication passages for selectively communicating between the ports are provided in the main valve body to move the main valve body. Thus, the ports that communicate with each other can be switched, and the main valve body is configured to be divided into two parts of an upper half part and a lower half part that can move integrally and move up and down. Between the lower half and separating them from each other It is characterized by biasing means for biasing the direction is interposed.

  In a specific preferred embodiment, at least one first communication passage capable of communicating at least one of the ports and the other, and one of the ports and another one in the main valve body. Between the ports communicating with each other by the second communicating passage from the ports communicating with the first communicating passage by moving the main valve body in one direction. By switching the flow path to the flow path, the main valve body is moved in the other direction after the flow path is switched, so that the port communicated by the second communication path is changed to the port communicated by the first communication path. Channel switching is performed.

  In a more specific preferred embodiment, the upper valve seat is provided with first and second ports, the lower valve seat is provided with third and fourth ports, and the main valve body is provided with the main valve body. Is provided with a first communication path for communicating the first port and the third port, and a second communication path for communicating the second port and the fourth port. When the valve body takes the second movement position, a third communication path for communicating the first port and the second port and a fourth communication path for communicating the third port and the fourth port are provided.

  In another preferred embodiment, at least one of the plurality of communication passages is constituted by a linear passage as a whole, and the remaining at least one passage is constituted by a U-shaped passage.

  At both end portions of the communication passage, preferably, a convex portion having an annular seal surface that is in close contact with an opening of each port in the upper valve seat and / or the lower valve seat is provided.

  In a preferred embodiment, as one of the communication paths, there is a divided communication path straddling the upper half part and the lower half part, and a lower end part and a lower half part of the upper half part of the divided communication path. A large-diameter portion is formed on one of the upper end portions, and a cylindrical portion inserted into the large-diameter portion is extended on the other, and an O-ring is interposed between the large-diameter portion and the cylindrical portion. The

  In another preferred embodiment, when the main valve body is moved between the upper half portion and the upper valve seat and between the lower half portion and the lower valve seat, the seal surface on the main valve body side is provided. Is provided with a ball-type sealing surface separation mechanism for separating the upper valve seat and the lower valve seat.

  Preferably, the ball-type sealing surface separation mechanism includes a ball and a housing portion that accommodates the ball in a state in which a part of the ball protrudes in the vertical direction and is rotatable and substantially prevented from moving. The ball protruding from the housing portion so that the seal surface on the main valve body side is not separated from the upper valve seat and the lower valve seat before the main valve body starts moving and at the end of movement. And a concave hole having a size and shape so that the ball pushes down the upper half and rolls up while pushing up the lower half when the main valve body is moved. The ball and the accommodating portion are provided at two or more places in the upper half portion and the lower half portion, and the concave hole is the same as the accommodating portion in plan view in the upper valve seat and the lower valve seat. Position and It said main valve body from the position are respectively provided at a position away by a distance which moves the flow path switching.

  The concave hole is preferably formed in a rail laid on the upper valve seat and the lower valve seat.

  In another preferred aspect, the actuator includes a reciprocating drive cylinder having a variable volume first working chamber and a second working chamber, hermetically partitioned by a piston, into which a high-pressure fluid in the main valve is introduced. A high-pressure fluid is introduced into the first working chamber, and the high-pressure fluid is discharged from the second working chamber to move the main valve body in one direction, and the high-pressure fluid is introduced into the second working chamber. And discharging a high-pressure fluid from the first working chamber so that the second stroke of moving the main valve body in the other direction can be selectively performed.

  In a further preferred aspect, a first cylinder having the first working chamber is provided on the front side of the main valve housing, and a second cylinder having the second working chamber is provided on the rear side of the main valve housing, A first pusher plate connected to the piston rod of the first cylinder is brought into contact with the front surface of the main valve body, and a second pressure plate connected to the piston rod of the second cylinder is connected to the rear surface of the main valve body. The push plate is brought into contact.

  In a further preferred aspect, the first cylinder and the second cylinder have a common piston rod that interconnects the respective pistons, and the first push plate and the second push plate are connected to the piston rod. In addition to being fixed, a portion of the piston rod between the first pusher plate and the second pusher plate is inserted into a front and rear through-hole provided in the main valve body so as to be slightly movable up and down. .

  In another preferable aspect, the four-way pilot valve connected to the first working chamber and the second working chamber, and the high pressure portion and the low pressure portion of the main valve is switched between the first stroke and the second stroke. To do so.

  In the flow path switching valve according to the present invention, since all the ports are provided in the upper valve seat and the lower valve seat of the main valve housing, for example, two of the four communication paths communicating between the ports are The thickness (passage diameter) from the start to the end is a straight passage that is almost the same as the diameter of each port, allowing fluid to flow straight from the port directly below or directly above, so that the main valve (main valve body) ) Can effectively suppress the occurrence of pressure loss. In addition, the remaining communication passages can be prevented from changing the effective passage area so much from the start to the end by providing a guide part with a specific shape at the bent portion (the portion in which the flow direction changes), and the vortex at the bent portion. This makes it difficult to generate a flow, thereby suppressing the expansion and contraction of the fluid in the communication path and reducing the resistance to the fluid flowing through the communication path. As a result, the fluid can flow smoothly and pressure loss In total, the pressure loss can be considerably reduced as compared with the conventional flow path switching valve.

  In addition, the main valve body that receives high pressure has a rectangular parallelepiped shape, and a communication path composed of straight through passages is provided in the interior, and U-shaped communication paths are provided in the upper and lower sides of the communication path. In addition, the flow path switching balance can be improved, and sufficient strength and durability can be secured.

  In addition, the surface to be sealed, that is, the upper valve seat and the lower valve seat, which are the portions in which the main valve body (the upper half and the lower half) are in sliding contact when the flow path is switched, are formed in a flat plate shape. The surface to be sealed can be a flat and smooth surface (the surface accuracy can be easily increased), and the sealing performance can be remarkably improved.

  Furthermore, since all the ports are provided in the upper valve seat and the lower valve seat of the main valve housing, the piping can be easily routed and the substantial occupied space including the piping can be reduced.

  In addition, the main valve body is divided into two parts, the upper half and the lower half, so that the upper half and the lower half can be moved up and down independently, and between the upper half and the lower half. When an urging means such as a compression coil spring is interposed, the upper half and the lower half can be pressed against the valve seat surface by the urging force. In addition, by projecting protrusions on the main valve body side (both ends of each communication passage) and using the end surfaces as annular sealing surfaces, the area of the portion that contacts the valve seat surface can be minimized. The contact pressure can be increased. By these, sufficient sealing performance can be ensured and valve leakage can be suppressed more effectively.

  In addition, by providing a ball type seal surface separation mechanism, when the main valve body is moving (switching the flow path), the seal surface on the main valve body side is the valve seat surface of the upper valve seat and the lower valve seat. Therefore, there is almost no sliding friction, so that stick slip or the like can hardly occur, wear of the sliding portion can be greatly suppressed, and further, wear is suppressed, so that sealing performance is improved. This improves the valve leakage more effectively.

  In addition to the above, when the flow path switching valve according to the present invention 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 air conditioning system, each communication path is relatively large in the main valve body. Because it is provided separately, the amount of heat exchange in the main valve housing compared to the conventional type in which the high-temperature and high-pressure refrigerant and the low-temperature and low-pressure refrigerant flow close to each other (a state where one thin wall is separated) As a result, the efficiency of the system can be improved.

  In addition, a fluid pressure type actuator that reciprocally moves the main valve body using the differential pressure between the high-pressure fluid and the low-pressure fluid supplied into the main valve as the actuator is adopted. Compared with the case where the actuator is directly moved, cost reduction, power consumption reduction, energy saving, and the like can be achieved.

  Problems, configurations, and operational effects other than those described above will be clarified by the following embodiments.

The top view which shows the state which has the main valve body in the 1st movement position in one Example of the flow-path switching valve which concerns on this invention. The top view which shows the state which has the main valve body in the 2nd movement position in one Example of the flow-path switching valve which concerns on this invention. Sectional drawing according to the AA arrow line of FIG. Sectional drawing which follows the AA arrow line of FIG. Sectional drawing which follows the BB arrow line of FIG. Sectional drawing which follows the BB arrow line of FIG. Sectional drawing which follows the CC arrow line of FIG. (A) is a fragmentary sectional view which follows the DD arrow line of FIG. 3, (B) is a fragmentary sectional view which follows the EE arrow line of (A). The expanded sectional view with which the structure and operation | movement description of the seal surface separation mechanism provided in the flow-path switching valve of the said Example are provided. The partial notch top view which shows the flow-path switching valve of the said Example with an example of the four-way pilot valve with which the actuator provided in it is provided. The front view which shows the flow-path switching valve of the said Example with an example of the four-way pilot valve with which the actuator provided in it is provided. FIG. 11 is an enlarged cross-sectional view showing the four-way pilot valve shown in FIG. 10, (A) when energization is OFF, and (B) when energization is ON. The schematic block diagram which shows an example of a heat pump type | formula air conditioning system.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a top view showing a state in which the main valve body is in the first movement position in an embodiment of the flow path switching valve according to the present invention, and FIG. It is a top view which shows the state in a movement position. 3 and 4 are sectional views taken along the line AA in FIGS. 1 and 2, respectively, and FIGS. 5 and 6 are sectional views taken along the line BB in FIGS. 3 and 4, respectively.

  In the present specification, descriptions indicating positions, directions such as up and down, left and right, and front and rear are provided for the sake of convenience in accordance with the drawings in order to avoid complicated explanation, and are actually incorporated in a heat pump type air conditioning system or the like. It does not necessarily indicate the position and direction in the state of being pressed.

  In each drawing, the gap formed between the members, the separation distance between the members, etc. are larger than the dimensions of each constituent member for easy understanding of the invention and for convenience of drawing. Or it may be drawn small.

  The flow path switching valve 1 in the illustrated embodiment is a slide type four-way switching valve, which is used as, for example, the four-way switching valve 140 in the heat pump air conditioning system 100 shown in FIG. 13 described above. A main valve 5 having a main valve body 20 disposed in the main valve housing 10 so as to be capable of reciprocating linear movement in the front-rear direction (hereinafter sometimes abbreviated as front-rear movement) and being movable up and down; And a hydraulic actuator 7 having a four-way pilot valve 80 (see FIGS. 10 and 11 to be described later).

  The main valve housing 10 of the main valve 5 is made by metal molding (aluminum die casting or the like) using a metal material such as aluminum or stainless steel, and has a rectangular parallelepiped box-shaped portion 10C having an open front surface. The front lid member 10D has a thick rectangular plate-like front lid member 10D that is fixed by caulking so as to hermetically seal the front opening of the box-shaped portion 10C and is hermetically bonded by soldering, brazing, welding, or the like. The upper surface portion and the lower surface portion of the box-shaped portion 10C are an upper valve seat 10A and a lower valve seat 10B, respectively, and the lower surface of the upper valve seat 10A and the upper surface of the lower valve seat 10B are flat and smooth valve seat surfaces 17 respectively. 17

  A first port 11 and a second port 12 made of pipe joints are provided vertically on the left and right sides of the upper valve seat 10A, and pipes are provided on the left and right sides of the lower valve seat 10B with a predetermined interval J. A third port 13 and a fourth port 14 made of a joint are provided vertically. Here, the first port 11 and the third port 13 and the second port 12 and the fourth port 14 are arranged at the same position in plan view.

  In the present embodiment, when incorporated in the heat pump type air conditioning system 100 as shown in FIG. 13, for example, the first port 11 is a discharge side high-pressure port D connected to the compressor discharge side, and the second port 12 is an indoor input / output port E connected to the indoor heat exchanger, a third port 13 is an outdoor input / output port C connected to the outdoor heat exchanger, and a fourth port 14 is connected to the compressor suction side. The suction side low pressure port S.

  Near the left and right ends of the upper valve seat 10A and the lower valve seat 10B in the main valve housing 10, a pair of left and right rails 44, 44 are provided on the rail surface (for the sake of convenience when the main valve body 20 is moved back and forth. The main valve body contact surface) is laid in parallel in the front-rear direction with the valve seat surface 17 being flush with the valve seat surface 17 (details will be described later).

  The main valve body 20 disposed in the main valve housing 10 has a two-part configuration of an upper half 20A and a lower half 20B having a short prism shape. Specifically, the upper half portion 20A is constituted by a relatively thick first layer member 21 and a second layer member 22 integrally joined to the lower surface side of the first layer member 21 by welding or the like. The lower half portion 20B is constituted by the layer member 23 and the relatively thick fourth layer member 24 integrally joined to the lower surface side of the third layer member 23 by welding or the like.

  Between the upper half 20A (second layer member 22) and the lower half 20B (third layer member 23), as shown in FIG. 8, they are urged away from each other. Four compression coil springs 29 as urging means are mounted. The four compression coil springs 29 are loaded in the four spring accommodating holes 23h provided near the four corners on the upper surface side of the third layer member 23 so that a part thereof protrudes upward.

  When switching the flow path, the main valve body 20 is reciprocated in the front-rear direction by an actuator 7 to be described later, and a first movement position as shown in FIGS. 1 and 5 and a rearward direction from the first movement position. And a second movement position as shown in FIGS. 2 and 6 that is moved by a predetermined distance L (see FIGS. 1 and 2).

  When the main valve body 20 is in the first movement position, the linear first communication passage 31 and the second port 12 and the fourth port 14 that communicate the first port 11 and the third port 13 communicate with each other. And a U-shaped third communication passage 33 and a third port for communicating the first port 11 and the second port 12 when taking the second movement position. 13 and the 4th port 14 are provided in the U-shaped 4th communicating path 34 (it mentions later for details).

On the other hand, on the front side of the main valve housing 10 (the front lid member 10D) and the rear side of the box-shaped portion 10C, a first cylinder 50A and a second cylinder 50B constituting the reciprocating drive cylinder 50 are arranged in the front-rear direction. Each projecting.

  The first cylinder 50 </ b> A has a cylinder portion 51 provided across the front lid member 10 </ b> D (thickness portion) and the front protruding portion, and in this cylinder portion 51, a piston 52 with a packing 53 extends in the front-rear direction. A variable volume first working chamber 55 </ b> A is formed that is slidably inserted and hermetically sealed by the piston 52 with packing 53.

  The second cylinder 50 </ b> B has a cylinder part 51 provided at a rearward projecting part of the main valve housing 10, and a piston 52 with a packing 53 is fitted into the cylinder part 51 so as to be slidable in the front-rear direction. A variable volume second working chamber 55B that is hermetically sealed by the piston 52 with the packing 53 is formed.

  The first cylinder 50 </ b> A and the second cylinder 50 </ b> B have a common piston rod 54 that interconnects the respective pistons 52, 52. A rectangular plate-like first pusher plate 58A that is brought into contact with the front surface is fixed, and a rectangular plate-like second pusher made to come into contact with the rear surface of the main valve body 20 is located near the rear end of the intermediate portion. The plate 58B is fixed. 58 A of 1st push plates and the 2nd push plate 58B are set as the magnitude | size which can press the substantially whole area of the front surface of the main valve body 20, and a rear surface, respectively.

  Further, the portion of the piston rod 54 between the first pushing plate 58A and the second pushing plate 58B is a front and rear of an oblong cross section provided in the substantially central portion (third layer member 23) of the main valve body 20. It is inserted into the through hole 60 so as to be slightly movable up and down.

  Note that the first push plate 58A and the second push plate 58B are fixed to the piston rod 54, for example, as can be understood by referring to FIG. 7 in addition to FIGS. A slit-shaped notch 61 having a lower surface opened below the central portion of 58A and the second pusher plate 58B is formed, and a pair of left and right fitting grooves 62 are formed in the piston rod 54 by parallel chamfering on both sides. The left and right edges of the slit-shaped notch 61 are pressed into the fitting groove 62 from above until the upper end of the slit-shaped notch 61 comes into contact with the piston rod 54, and then fixed by welding or the like as necessary. The

  The first working chamber 55A of the first cylinder 50A is provided with a first inlet / outlet port 56A for introducing and discharging a high-pressure fluid into the first working chamber 55A, and the second working chamber of the second cylinder 50B. 55B is provided with a second inlet / outlet port 56B for introducing and discharging a high-pressure fluid into the second working chamber 55B. The first inlet / outlet port 56 </ b> A and the second inlet / outlet port 56 </ b> B are open at a site (on the left side) in the vicinity of the protruding end of the cylinder portion 51.

  Here, the main valve body 20 is in a first movement position where the first pusher plate 58A contacts the front lid member 10D and is prevented from moving forward (FIGS. 1 and 5). The second pusher plate 58B selectively contacts the rear wall 10E of the box-shaped portion 10C and is in the second movement position where the backward movement is prevented (FIGS. 2 and 6). Have been to get.

  In other words, the front lid member 10D and the rear wall 10E serve as a stopper that stops the main valve body 20 from moving back and forth, and the first pusher when the main valve body 20 is in the second movement position (FIG. 2). The separation distance between the moving plate 58A and the front lid member 10D and the separation distance between the second pushing plate 58B and the rear wall 10E of the box-shaped portion 10C when the main valve body 20 is in the first movement position (FIG. 1). Therefore, the movement distance from the first movement position to the second movement position and the movement distance from the second movement position to the first movement position in the main valve body 20 are both L. It is said.

  In a state where the main valve body 20 is in the first movement position (FIGS. 1 and 5), high-pressure fluid is introduced into the first working chamber 55A via the first inlet / outlet port 56A, and the second working chamber 55B When the high-pressure fluid is discharged via the two inlet / outlet ports 56B, the pistons 52, 52 of the first cylinder 50A and the second cylinder 50B move rearward, and accordingly, the main valve body 20 is moved to the first by the first pushing plate 58A. The second pusher plate 58B comes into contact with the rear wall 10E of the box-shaped portion 10C and is prevented from moving rearward. The movement distance at this time is L, and the position at this time is the second movement position (the movement from the first movement position to the second movement position is referred to as a backward movement stroke).

  On the other hand, in a state where the main valve body 20 is in the second movement position (FIGS. 2 and 6), high-pressure fluid is introduced into the second working chamber 55B via the second inlet / outlet port 56B, and the first working chamber When the high-pressure fluid is discharged from 55A through the first inlet / outlet port 56A, the pistons 52 and 52 of the first cylinder 50A and the second cylinder 50B move forward, and accordingly, the main valve body 20 is moved by the second pushing plate 58B. Is pushed forward from the second movement position, and eventually the first pusher plate 58A comes into contact with the front lid member 10D and is prevented from moving forward. The movement distance at this time is L, and the position at this time is the first movement position (the movement from the second movement position to the first movement position is referred to as a forward movement stroke).

  Next, the structure of the main valve body 20 and the 1st-4th communication paths 31-34 provided in it is demonstrated in detail.

  The upper surface opening and / or the lower surface opening of each passage portion provided in the first to fourth layer members 21 to 24 constituting the first to fourth communication passages 31 to 34 are the first to fourth ports 11 to 14. Are arranged at the same position in plan view, and the diameter thereof is substantially the same as the diameter of each of the ports 11 to 14, and the effective passage area (passage diameter) of each passage portion. The overall length is substantially the same as the diameter of each of the ports 11-14.

  The first layer member 21 constituting the upper part of the upper half 20A of the main valve body 20 is penetrated by two straight lines with a predetermined interval J (same as the interval between the first port 11 and the second port 12) on the left and right. The passage portions 21A and 21B are provided, and the passage portions 21C and 21D with two horizontal holes connected by the horizontal holes 21E that are linear in a plan view and whose lower surface opening is blocked by the second layer member 22 are provided. The passage portions 21C and 21D with the horizontal holes are arranged at a predetermined interval J on the left and right sides, and the two form a U-shaped third communication passage 33 together. The configuration and effect of the third communication path 33 will be described in detail later. The separation distance between the straight through-passage portions 21A and 21B and the passage portions 21C and 21D with the horizontal holes is equal to the movement distance L of the main valve body 20 from the first movement position to the second movement position described above. .

  Therefore, when the main valve body 20 is in the first movement position, the straight through passage portions 21A and 21B are located directly below the first port 11 and the second port 12, and the main valve body 20 is moved from the first movement position. When moved rearward by the distance L, the main valve body 20 moves to the second movement position, the upper surface openings of the straight through passage portions 21A, 21B are closed by the upper valve seat 10A, and the passage portions 21C with side holes, The upper surface opening of 21D is located directly below the first port 11 and the second port 12.

  On the contrary, when the main valve body 20 is moved forward by a distance L from the second movement position, the main valve body 20 is moved to the first movement position, and the upper surface openings of the passage portions 21C and 21D with side holes are opened. While being closed by the upper valve seat 10 </ b> A, the upper surface openings of the straight through passage portions 21 </ b> A and 21 </ b> B are positioned directly below the first port 11 and the second port 12.

  The second layer member 22 constituting the lower part of the upper half 20A of the main valve body 20 has two straight through-passage portions 22A, 22B, so as to be located directly below the straight through-passage portions 21A, 21B of the first layer member 21. 22B is provided.

In addition, the third layer member 23 constituting the upper part of the lower half 20B of the main valve body 20 has two straight through passages so as to be located directly below the straight through passage portions 22A and 22B of the second layer member 22. Portions 23A and 23B are provided.

  Similar to the first layer member 21, the fourth layer member 24 constituting the lower part of the lower half portion 20B of the main valve body 20 is provided with two straight through passage portions 24A and 24B with a predetermined interval J on the left and right. At the same time, there are provided two passage portions 24C and 24D with lateral holes, which are connected by lateral holes 24E having a straight line shape in plan view, the upper surface opening of which is closed by the third layer member 23. The passage portions 24C and 24D with the horizontal holes are arranged at a predetermined interval J on the left and right sides, and form a U-shaped fourth communication passage 34 together. The separation distance between the straight through-passage portions 24A and 24B and the passage portions with lateral holes 24C and 24D is equal to the movement distance L of the main valve body 20 from the first movement position to the second movement position described above. .

  Therefore, when the main valve body 20 is in the first movement position, the straight through passage portions 24A and 24B are located immediately above the third port 13 and the fourth port 14, and the main valve body 20 is moved to the first movement position. If the main valve body 20 is moved backward by a predetermined distance L, the main valve body 20 moves to the second movement position, the lower surface openings of the straight through-passage portions 24A and 24B are closed by the lower valve seat 10B, and a passage with a lateral hole The lower surface openings of the portions 24 </ b> C and 24 </ b> D are located directly above the third port 13 and the fourth port 14.

On the contrary, when the main valve body 20 is moved forward by a distance L from the second movement position, the main valve body 20 is moved to the first movement position, and the lower surface openings of the lateral hole passage portions 24C and 24D are opened. While being closed by the lower valve seat 10B, the lower surface openings of the straight through-passage portions 2 4 A and 2 4 B are located directly above the third port 13 and the fourth port 14.

  As shown in FIGS. 3 and 4, the ports 11 on the valve seat surfaces 17 and 17 of the upper valve seat 10 </ b> A and the lower valve seat 10 </ b> B are provided at both ends of the communication passages 31, 32, 33 and 34. A convex portion 36 having an annular sealing surface that is in close contact with the openings of -14 is provided.

  Further, as shown in FIG. 3, the first communication passage 31 and the second communication passage 32 are divided communication passages that straddle the upper half portion 20A and the lower half portion 20B of the main valve body 20. In order to ensure sealing performance, the following measures are taken. That is, to describe the first communication path 31 as a representative, a stepped large-diameter portion 22c is formed in the lower part of the straight through-passage portion 22A of the second layer member 22 constituting the first communication path 31, A cylindrical portion 23c is slidably inserted into the large diameter portion 22c at the upper end of the straight through-passage portion 23A of the third layer member 23, and between the large diameter portion 22c and the cylindrical portion 23c. An O-ring 28 is interposed, and a washer 27 is fixed to the lower end of the large diameter portion 22c by welding or the like in order to prevent the O-ring 28 from falling off. The second communication path 32 has a similar configuration.

  In addition to the above, in the present embodiment, the main valve body 20 is provided between the first layer member 21 of the main valve body 20 and the upper valve seat 10A and between the fourth layer member 24 and the lower valve seat 10B. Is provided with a ball-type seal surface separation mechanism 45 that separates the seal surface on the main valve body 20 side from the valve seat surfaces 17 of the upper valve seat 10A and the lower valve seat 10B.

  The ball-type seal surface separation mechanism 45 is provided between the first layer member 21 and the upper valve seat 10A as shown in a representative example in FIG. An accommodating portion 47 that accommodates a portion of the main valve body 20 that protrudes in the vertical direction and that is rotatable and substantially prevented from moving, and the main valve body 20 before the movement start and at the end of the movement. A part of the ball 46 protruding from the housing portion 47 is fitted so that the seal surface 37 on the body 20 side does not separate from the valve seat surface 17 of the upper valve seat 10A, and when the main valve body 20 starts to move (flow At the time of the start of the path switching, a conical concave hole 48 is provided which is dimensioned so that the ball 46 rolls while pushing down the main valve body 20. The concave hole 48 is formed in the rail 44 laid on the upper valve seat 10A, and the accommodating portion 47 is fixed to the round hole 47a and the round hole 47a by press-fitting or the like. It consists of a cylindrical retainer 47b.

  The accommodating portion 47 in which the ball 46 is accommodated moves the main valve body 20 in the front-rear direction at the same position in plan view near the four corners of the first layer member 21 and the fourth layer member 24 of the main valve body 20. The recess 48 is provided with a distance twice as long as the distance L, and the recess 48 is formed by the left and right rails 44, 44 laid on the upper valve seat 10 </ b> A and the lower valve seat 10 </ b> B in the plan view. A total of four positions are provided at the same position as 47 and a position away from the position by the movement distance L (see FIGS. 1 and 2).

  The rail 44 is not necessarily required, and the concave hole 48 may be provided directly in the upper valve seat 10A and the lower valve seat 10B. In the present embodiment, the rail 44 having the recessed holes 48 provided in four places as described above is prepared in advance, and a long groove in which the rail 44 is embedded is molded when the box-shaped portion 10C is molded (metal mold). The long groove forming portion of the mold can be removed forward after molding), a method of fitting the rail 44 with the recessed hole 48 into the long groove after molding, or a mold for the box-shaped portion 10C. A technique such as insert molding of the rail 44 with the recessed hole 48 together with molding is adopted.

  In the above-described ball type seal surface separation mechanism 45, before the movement of the main valve body 20 and at the end of movement, as shown in FIG. 9A, the ball 46 is placed in the concave hole 48 of the upper valve seat 10 </ b> A. Part is fitted. This fitting amount (height from the valve seat surface 17 of the upper valve seat 10A to the top of the ball 46) is defined as h. When the main valve body 20 starts to move from this state, the accommodating portion 47 also starts to move, and as a result, the ball 46 is moved to the main valve body 20 (upper half portion 20A) as shown in FIG. 9B. Is pushed out of the recessed hole 48 while being pushed down against the urging force of the compression coil spring 29 that is compressed between the upper half 20A and the lower half 20B. As a result, the seal surface 37 of the main valve body 20 is separated from the valve seat surface 17 of the upper valve seat 10A. The amount by which the main valve body 20 is pushed down at this time is the fitting amount h.

  When the main valve body 20 moves by the distance L, the ball 46 is fitted into the next concave hole 48, so that the main valve body 20 (upper half portion 20A) is pushed up by the urging force of the compression coil spring 29, and the main valve The sealing surface 37 of the body 20 is pressed against the valve seat surface 17 of the upper valve seat 10A.

  As can be understood from the above description, when the main valve body 20 takes the first movement position, the first communication passage 31 that connects the first port 11 and the third port 13 is the straight through passage portion 21A, The second communication path 32 that connects the second port 12 and the fourth port 14 is a straight through-passage portion 21B, 22B, 23B, and 24B. It becomes the linear path comprised.

  On the other hand, when the main valve body 20 takes the second movement position, the third communication passage 33 for communicating the first port 11 and the second port 12 is provided in the upper half portion 20A of the main valve body 20. A U-shaped passage formed of passage portions 21 </ b> C and 21 </ b> D with horizontal holes is provided, and a fourth communication passage 34 that communicates the third port 13 and the fourth port 14 is provided in the lower half portion 20 </ b> B of the main valve body 20. It becomes a U-shaped passage composed of the passage portions 24C and 24D with the horizontal holes.

  Here, as shown in FIG. 4, there is a horizontal hole between the passage portions 21C and 21D with the horizontal holes forming the third communication passage 33 and between the passage portions 24C and 24D with the horizontal holes forming the fourth communication passage 34. A relatively long guide portion 20G is provided on the side of 21E and 24E, with the bulging inner end side corners rounded in the left-right direction. The guide portion 20G can suppress the generation of vortex flow at the portion where the fluid (refrigerant) bends in a U-shape, and the effective passage area (passage diameter) of the side holes 21E and 24E and the diameters of the ports 11 to 14 Are substantially the same, the third communication passage 33 and the fourth communication passage 34 have a substantially constant passage diameter over the entire length thereof, thereby expanding the fluid in the third communication passage 33 and the fourth communication passage 34. Shrinkage does not occur, so pressure loss can be reduced.

  Temporarily, the upper half 20A (third communication passage 33) of the main valve body 20 is composed of two members, the first layer member 21 and the second layer member 22, and the lower half 20B (fourth communication passage) of the main valve body 20. 34) is not formed by the two members of the third layer member 23 and the fourth layer member 24, but when the upper half portion 20A and the lower half portion 20B are each formed as a single piece by molding, Since the side holes 21E and 24E of the communication passage 33 and the fourth communication passage 34 are undercut portions, the third communication passage 33 and the fourth communication passage 34 must be shaped like a bowl without the guide portion 20G. As a result, the generation of vortex flow cannot be suppressed, and the passage diameter cannot be made substantially constant, resulting in an increase in pressure loss.

  As described above, in the flow path switching valve 1 of the present embodiment, the first communication path 31 causes the main valve body 20 to move backward by a distance L from the first movement position toward the rear. Between the communicating ports 11-13 and the port 12-14 communicating with the second communicating path 32, between the ports 11-12 communicating with the third communicating path 33 and between the ports 13-14 communicating with the fourth communicating path 34 Between the ports 11-12 communicated by the third communication path 33 by performing a forward movement stroke in which the main valve body 20 is moved by a distance L from the second movement position to the front. In addition, the flow path is switched from between the ports 13-14 communicating with the fourth communication path 34 to the ports 11-13 communicating with the first communication path 31 and between the ports 12-14 communicating with the second communication path 32. That.

  When the flow path switching valve 1 of this embodiment is incorporated into a heat pump type air conditioning system as shown in FIG. 13, for example, the first port 11 is connected to the compressor discharge side as described above. The high pressure port D, the second port 12 are indoor side input / output ports E connected to the indoor heat exchanger, the third port 13 is an outdoor side input / output port C connected to the outdoor heat exchanger, and the fourth port 14 is a compressor suction port. The suction side low-pressure port S is connected to the side.

  And when performing a cooling operation, the main valve body 20 is made to take the 1st movement position. As a result, as indicated by white arrows in FIG. 3, the high-pressure refrigerant from the compressor flows from the discharge-side high-pressure port 11 (D) to the linear first communication path 31 to the outdoor inlet / outlet port 13 (C). While flowing, the low-pressure refrigerant from the indoor heat exchanger flows from the indoor-side inlet / outlet port 12 (E) to the linear second communication path 32 → the suction-side low-pressure port 14 (S).

  On the other hand, when performing the heating operation, the main valve body 20 is moved backward from the first movement position to take the second movement position. As a result, the flow path is switched, and as indicated by the white arrow in FIG. 4, the high-pressure refrigerant from the compressor is discharged from the high-pressure port 11 (D) → the U-shaped third communication path 33 → the indoor side. While flowing to the inlet / outlet port 12 (E), the low-pressure refrigerant from the outdoor heat exchanger goes to the outdoor inlet / outlet port 13 (C) → the reverse U-shaped fourth communication passage 34 → the suction side low-pressure port 14 (S). And flow.

  In the flow path switching valve 1 of the present embodiment configured as described above, the first communication path 31 and the second communication path 32 have a thickness (passage diameter) from the start end to the end, and the first port 11 and the second connection path 32 have the same configuration. The straight passage is substantially the same as the diameter of the port 12, and the refrigerant flows straight from the first port 11 and the second port 12 straight down, so that pressure loss in the main valve 5 (main valve body 20) is prevented. It can be effectively suppressed.

  In addition, since the U-shaped third communication path 33 and the fourth communication path 34 are provided with the guide portion 20G having a specific shape as described above, the effective path area can be prevented from changing so much from the start end to the end. It is difficult to generate a vortex flow in the U-shaped bent portion, thereby suppressing the expansion and contraction of the fluid in the communication passages 33 and 34, and reducing the resistance to the fluid flowing through the communication passages 33 and 34, As a result, the fluid can flow smoothly and the pressure loss can be reduced, and the total pressure loss can be considerably reduced as compared with the conventional flow path switching valve.

  In addition, the main valve body 20 that receives high pressure has a rectangular parallelepiped shape, and communication passages 31 and 32 including straight through passages are provided therein, and U-shaped communication passages 33 and 34 are provided above and below the communication passages 31 and 32. Therefore, the overall structure can be simplified, the flow path switching balance can be improved, and sufficient strength and durability can be secured.

  In addition, the surfaces to be sealed, that is, the upper valve seat 10A and the lower valve seat 10B, which are the portions with which the main valve body 20 (the upper half portion 20A and the lower half portion 20B) slidably contact when the flow path is switched, are flat. Therefore, the surface to be sealed can be a flat and smooth surface (the surface accuracy can be easily increased), and the sealing performance can be remarkably improved.

  Furthermore, since all the ports 11 to 14 are provided in the upper valve seat 10A and the lower valve seat 10B of the main valve housing 10, the piping can be easily handled and the substantial occupied space including the piping can be reduced. it can.

  Further, the main valve body 20 has a two-part configuration of an upper half portion 20A and a lower half portion 20B, and the upper half portion 20A and the lower half portion 20B can be moved up and down independently, and the upper half portion Since the compression coil spring 29 is mounted between the portion 20A and the lower half portion 20B, the upper half portion 20A is pushed up by the spring force, and the sealing surface thereof is in the valve seat surface 17 of the upper valve seat 10A. While being pressed around each port 11, 12, the lower half 20 </ b> B is pushed down and its sealing surface is pushed around each port 13, 14 in the valve seat surface 17 of the lower valve seat 10 </ b> B.

  In this case, since the convex part 36 is protrudingly provided in the main valve body 20 (upper half part 20A and lower half part 20B) side, and the end surface is made into the annular seal surface 37, it is the part which contacts the valve seat surface 17 Area is minimized, so that the contact surface pressure is increased. Due to these synergistic effects, sufficient sealing performance can be secured and valve leakage can be effectively suppressed.

  In addition, in the present embodiment, when the main valve body 20 moves (while the flow path is switched), the upper half portion 20A of the main valve body 20 is pushed down by the ball-type seal surface separation mechanism 45, and Since the half portion 20B is pushed up and the seal surface on the main valve body 20 side is separated from the valve seat surfaces 17 and 17 of the upper valve seat 10A and the lower valve seat 10B, there is almost no sliding friction. Therefore, stick-slip or the like can hardly occur, wear of the sliding portion can be significantly suppressed, and wear is further suppressed, so that the sealing performance is improved and valve leakage can be more effectively suppressed.

  Further, in the four-way switching valve having a conventional sliding main valve body as shown in Patent Document 1, the flow path opening area between the high pressure pipe D and the low pressure pipe S changes suddenly when the flow path is switched. An abnormal noise (switching noise) is generated when the high-pressure refrigerant is plunged into the low-pressure pipe. In order to prevent this abnormal noise, the frequency of the compressor is gradually reduced on the air conditioning system side so that the abnormal pressure due to the pressure difference between the high pressure pipe D and the low pressure pipe S is acceptable. It was necessary to switch the flow path. In the flow path switching valve 1 of this embodiment, the main valve body is switched from the valve seat surface by the amount h of fitting by the ball-type seal surface isolation mechanism 45, so that switching is performed. Therefore, the flow path opening area between the high-pressure pipe D and the low-pressure pipe S does not change abruptly, and therefore the above-mentioned abnormal noise can be suppressed. Further, by appropriately changing the fitting amount h, the degree of decrease in the compressor frequency at the time of switching the flow path can be made smaller than that of the air conditioning system using the four-way switching valve of Patent Document 1, and the frequency of the compressor It is also possible to switch the flow path without lowering.

  In addition to the above, when the flow path switching valve 1 of the present embodiment is used in an environment in which a high-temperature and high-pressure refrigerant and a low-temperature and low-pressure refrigerant are flowed, such as a heat pump type air conditioning system, the communication paths 31 to 34 are the main valve bodies. Compared to the conventional type in which the high-temperature and high-pressure refrigerant and the low-temperature and low-pressure refrigerant are flowed close to each other (a state in which one thin wall is separated), The amount of heat exchange in the valve housing 10 can be greatly reduced, so that the efficiency of the system can be improved.

  In the above embodiment, the upper half portion 20A is composed of the first layer member 21 and the second layer member 22 joined thereto, and the third layer member 23 and the fourth layer member 24 joined thereto. The lower half portion 20B is configured as described above, but instead, the upper half portion 20A and the lower half portion 20B may be manufactured as a single unit from the beginning with a 3D printer or the like. The lower half 20B may be manufactured as an integral part, that is, the main valve body 20 may be manufactured as one member.

  Moreover, in the said Example, although the four-way switching valve 1 was illustrated, the flow-path switching valve based on this invention is not restricted to a four-way switching valve, It can apply also to a three-way switching valve etc. In the case of the three-way switching valve, in the flow path switching valve (four-way switching valve) 1 of the above embodiment, for example, the upper half portion 20A is manufactured as an integral body from the beginning (it is not necessary to form a U-shaped communication path). Therefore, the second port 12 provided in the main valve housing 10 is eliminated, and the straight through-passage portions 21B, 22B, 23B, and 24B that constitute the second communication passage 32 and the third communication passage 33 and the passage portion with a horizontal hole are provided. 21C and 21D and the portions associated therewith are deleted, and the communication path is a linear first communication path that allows the first port 11 and the third port 13 to communicate when the main valve body 20 assumes the first movement position. When the main valve body 20 is in the second movement position, a U-shaped fourth communication passage 34 that communicates the third port 13 and the fourth port 14 may be used.

  In addition, when using the said three-way switching valve for the heat pump type air conditioning system mentioned above, two said three-way switching valves are used, and it works as a four-way switching valve, or switching of a refrigerant | coolant or a cold / warm air supply destination (for example, Used to switch between sending to one of the two rooms or sending to the other).

  Next, the configuration and operation of the four-way pilot valve 80 provided in the actuator 7 having the first and second cylinders 50A and 50B will be described with reference to FIGS.

  In the present embodiment, the flow path switching, that is, the switching between the backward movement stroke and the forward movement stroke, is performed by the first inlet / outlet port 56A and the second inlet / outlet port 56B in the first and second cylinders 50A and 50B. The first port 11 (which is the discharge-side high-pressure port D, sometimes referred to as the high-pressure port 11), which is the high-pressure portion of the valve 5, and the fourth port 14 (which is the suction-side low-pressure port S, which is the low-pressure port 14). This is performed by an electromagnetic four-way pilot valve 80 connected to the motor.

  The four-way pilot valve 80 is mounted horizontally on the rear side of the left side surface portion of the box-shaped portion 10C in the main valve housing 10 via a U-shaped base end side mounting tool 65 and a receiving side mounting tool 66 (attachment). Details of the tools 65 and 66 will be described later).

  The structure of the four-way pilot valve 80 is well known, and as shown in FIG. 12 (in FIG. 12, the vertical direction and the front-rear direction are different from those in the other drawings), a coil 82a for energizing excitation is provided. A cover case 82b covering the outer periphery of the coil 82a, a suction element 84 disposed on the inner peripheral side of the coil 82a and fixed to the cover case 82b by a bolt 82c, a plunger 85 disposed opposite to the suction element 84, and the like. ing. The plunger 85 is slidably fitted into a cylindrical guide pipe 86 in which one end (the upper end in FIG. 12, the same applies hereinafter) is disposed between the coil 82a and the attractor 84. The upper end portion of the guide pipe 86 is fixed to the outer peripheral terrace portion of the suction element 84 by welding or the like, and the filter-attached lid member 81 having a thin tube insertion hole is hermetically sealed by welding, brazing, caulking, or the like at the lower end side opening portion. A region surrounded by the cover member 81, the plunger 85, and the guide pipe 86 is a valve chamber 88.

  Further, a plunger spring 87 that urges the plunger 85 in a direction away from the suction element 84 (downward in FIG. 12) is mounted between the suction element 84 and the plunger 85.

  A mounting opening 86a is formed between the lower end of the plunger 85 and the lid member 81 in the guide pipe 86. The inner end surface of the mounting opening 86a is a valve seat (valve seat) 92, and its upper surface (the plunger 85 side). The outer periphery of the end opposite to the valve seat side of the valve seat block 83 having a rectangular cross-sectional outer shape, which is used as a stopper surface that restrains the movement of the plunger 85 in the direction away from the suction element 84, is welded or the like. Is hermetically sealed. The opposite side of the valve seat block 83 from the valve seat side is a cylindrical surface along the outer peripheral surface of the guide pipe 86, and the cylindrical surface of the valve seat block 83 and the periphery of the joint portion of the mounting opening 86 a of the guide pipe 86. Is closely attached to a mounting seat 66a (see also FIG. 11) having a circular arc cross section of a receiving side fixture 66, which will be described later, and hermetically sealed by welding or the like, whereby the four-way pilot valve 80 is received. 66 and the base end side attachment tool 65 are fixedly attached to the main valve housing 10.

  A valve body holder 90 that holds the valve body 91 slidably in the thickness direction on the free end side of the plunger 85 on the side opposite to the suction element 84 side caulks the wide base end portion 96. It is fixed by mounting. A leaf spring 94 that urges the valve body 91 in a direction (thickness direction) to press the valve body 91 against the valve seat 92 is attached to the valve body holder 90. The valve body 91 slides on the seat surface of the valve seat 92 as the plunger 85 moves up and down.

  The valve seat 92 is provided with a port a, a port b, and a port c in order from the bottom, and the valve body 91 can selectively communicate the port a with the port b and the port b with the port c. A recess 93 that is recessed in the thickness direction is provided. The valve seat block 83 has one end portion of the narrow tube 95a communicating with only the port a, one end portion of the thin tube 95b communicating with only the port b, and one end portion of the narrow tube 95c communicating with only the port c. Are inserted respectively. Further, one end of a thin tube 95d is inserted into the lid member 81.

  On the other hand, as shown in FIGS. 10 and 11, the thin tubes 95a, 95b, 95c, and 95d are routed along the outer surface of the main valve housing 10, and the other end of the thin tube 95a The first cylinder 50A is connected to the first working chamber 55A via the first inlet / outlet port 56A, the other end of the thin tube 95b is connected to the low pressure port 14, and the other end of the thin tube 95c is connected to the second cylinder 50B. The second working chamber 55B is connected to the second working chamber 55B through the two inlet / outlet ports 56B. The other end of the thin tube 95d is connected to the high pressure port 11.

  Next, a description will be given of a base end side mounting tool 65, a receiving side mounting tool 66, and the like for mounting the four-way pilot valve 80 horizontally on the rear part of the left side surface portion of the box-shaped part 10C in the main valve housing 10. The proximal end fitting 65 has a rectangular flat plate-like vertical side portion 65 a and upper and lower horizontal side portions 65 b and 65 c, and the vertical side portion 65 a (the outer peripheral portion) of the box-shaped portion 10 C in the main valve housing 10. It is fixed to the rear part of the left side surface part by welding or the like. Further, through holes 65b and 65c are formed with through holes for set screws 70 used for connection and fixation with the receiving side fixture 66, respectively, and the inner side of the through holes in the lower side part 65c. A burring portion 65d into which the set screw 70 is screwed is formed on the outer peripheral edge.

  On the other hand, the receiving-side fixture 66 has an inverted U-shape that is such that the proximal-side fixture 65 is reversed left and right, and a vertical side portion of the receiving-side fixture 66 follows the outer peripheral surface of the guide pipe 86 of the four-way pilot valve 80. An arcuate mounting receiving seat 66a (see also FIG. 11) is provided, and rectangular flat plate-shaped lateral sides 66b and 66c are provided at both upper and lower ends of the mounting receiving seat 66a. The distance between the lateral sides 66b and 66c of the receiving side fixture 66 is the same as that of the proximal end side fixture 65, but the width of the lateral sides 66b and 66c is wider than that of the proximal side fixture 65, The upper and lower lateral sides 66b and 66c of the receiving side fixture 66 are positioned below the upper and lower lateral sides 65b and 65c of the proximal end side fixture 65, respectively. In addition, a through hole of a set screw 70 provided for connection and fixation with the proximal end side mounting tool 65 is formed in each of the lateral side portions 66b and 66c, and the inner side of the through hole in the upper lateral side portion 66b. A burring portion 66d into which the set screw 70 is screwed is formed at the outer peripheral edge portion.

  When the four-way pilot valve 80 is attached to the main valve housing 10, as described above, the periphery of the joint between the valve seat block 83 and the attachment opening 86 a of the guide pipe 86 is welded to the attachment receiving seat 66 a of the receiving fixture 66. After the joining, the receiving side fixture 66 is fastened and fixed to the base end side fixture 65 with set screws 70, 70.

  In the four-way pilot valve 80 configured as described above, when the energization is turned off, the plunger 85 is brought into contact with the valve seat block 83 by the biasing force of the plunger spring 87 as shown in FIG. It is pushed down to the position where In this state, the valve body 91 is positioned on the port a and the port b, and the port a and the port b communicate with each other by the concave portion 93, and the port c and the valve chamber 88 communicate with each other. Is introduced into the second working chamber 55B through the thin tube 95d → the valve chamber 88 → the port c → the thin tube 95c → the second inlet / outlet port 56B, and the high pressure fluid in the first working chamber 55A is introduced into the first inlet / outlet port 56A → the narrow tube 95a. → Port a → Recess 93 → Port b → Narrow tube 95b → Low pressure port 14 is discharged.

  On the other hand, when the energization is ON, the plunger 85 is pulled to a position where the upper end of the plunger 85 contacts the suction element 84 by the suction force of the suction element 84 as shown in FIG. At this time, the valve body 91 is positioned on the port b and the port c, and the port b and the port c communicate with each other by the concave portion 93, and the port a and the valve chamber 88 communicate with each other. The thin tube 95d → the valve chamber 88 → the port a → the thin tube 95a → the first inlet / outlet port 56A is introduced into the first working chamber 55A, and the high pressure fluid in the second working chamber 55B is introduced into the second inlet / outlet port 56B → the narrow tube 95c → It flows from port c → recess 93 → port b → fine tube 95b → low pressure port 14 and is discharged.

  Therefore, when the energization is turned off from the energization OFF, the backward movement stroke is taken, the main valve body 20 moves from the first movement position to the second movement position, and the flow path switching as described above is performed. When the energization is turned on, the forward movement stroke is taken, the main valve body 20 moves from the second movement position to the first movement position, and the flow path switching as described above is performed.

  Thus, in addition to the effect by the structure of the main valve 5 described above, the following effect is obtained in the flow path switching valve 1 of the present embodiment.

  That is, the main valve body 20 is reciprocated using the differential pressure between the high-pressure fluid and the low-pressure fluid flowing through the main valve 5 by switching the energization to the electromagnetic four-way pilot valve 80 ON / OFF. Therefore, compared to the case where the main valve body 20 is directly moved by an electromagnetic or electric actuator, cost reduction, power consumption reduction, energy saving, and the like can be achieved.

  Of course, the flow path switching valve according to the present invention can be incorporated not only in the heat pump air conditioning system but also in other systems, devices, and devices.

  The material of the main valve housing 10 and the main valve body 20 is not particularly limited as long as it can withstand the pressure of the fluid to be introduced, such as a metal such as aluminum or stainless steel or a synthetic resin. There may be.

DESCRIPTION OF SYMBOLS 1 Flow path switching valve 5 Main valve 7 Actuator 10 Main valve housing 10A Upper valve seat 10B Lower valve seat 10C Box-shaped part 10D Front cover member 11 1st port 12 2nd port 13 3rd port 14 4th port 17 Valve seat Surface 20 Main valve body 20A Upper half part 20B Lower half part 21 First layer member 22 Second layer member 23 Third layer member 24 Fourth layer member 29 Compression coil spring 31 First communication path 32 Second communication path 33 Third Communication path 34 Fourth communication path 36 Convex portion 44 Rail 45 Ball type seal surface separation mechanism 46 Ball 47 Housing portion 48 Recessed hole 50 Reciprocating drive cylinder 50A First cylinder 50B Second cylinder 55A First working chamber 55B Second working chamber 56A First inlet / outlet port 56B Second inlet / outlet port 58A First pushing plate 58B Second pushing plate 80 Four-way pilot valve 83 Valve seat block 85 Plunger 88 Valve chamber 90 Valve body holder 91 Valve body 92 Valve seat 93 Recesses a, b, c Port (four-way pilot valve)
95a, 95b, 95c, 95d Narrow tube D Discharge side high pressure port S Suction side low pressure port C Outdoor input / output port E Indoor input / output port

Claims (13)

A total of at least three prismatic main valve housings whose upper and lower openings are hermetically sealed by the upper valve seat and the lower valve seat, the upper valve seat and / or the lower valve seat. A main valve having a main valve body movably disposed in the main valve housing, and a hydraulic actuator for moving the main valve body,
In the main valve body, a plurality of communication passages for selectively communicating between the ports are provided, and by moving the main valve body, the ports to be communicated are switched ,
The main valve body is configured to be divided into an upper half part and a lower half part that can move integrally and move up and down, and between the upper half part and the lower half part, in a direction away from each other. A flow path switching valve characterized in that biasing means for biasing is interposed .   At least one first communication passage capable of communicating at least one of the ports with another one and at least one of the ports and another one within the main valve body. The second communication path is provided, and the main valve body is moved in one direction to switch the flow path from the port communicating with the first communication path to the port communicating with the second communication path. Then, after the flow path is switched, the main valve body is moved in the other direction so that the flow path is switched from the port communicating with the second communication path to the port communicating with the first communication path. The flow path switching valve according to claim 1, wherein the flow path switching valve is provided. The upper valve seat is provided with first and second ports, and the lower valve seat is provided with third and fourth ports,
When the main valve body is in the first movement position, the first communication passage for communicating the first port and the third port and the second port and the fourth port are communicated with the main valve body. A double passage is provided,
When the main valve body takes the second movement position, a third communication path for communicating the first port and the second port and a fourth communication path for communicating the third port and the fourth port are provided. The flow path switching valve according to claim 1, wherein the flow path switching valve is provided.   2. At least one of the plurality of communication passages is constituted by a linear passage as a whole, and at least one of the remaining communication passages is constituted by a U-shaped passage. 4. The flow path switching valve according to any one of 3.   2. A protruding portion having an annular sealing surface that is in close contact with an opening of each port in the upper valve seat and / or the lower valve seat is provided at both ends of the communication passage. To 5. The flow path switching valve according to any one of 4 to 4. As one of the communication paths, there is a divided communication path straddling the upper half part and the lower half part, and the lower end part of the upper half part and the upper end part of the lower half part of the divided communication path A large-diameter portion is formed on one side, a cylindrical portion inserted into the large-diameter portion is extended on the other side, and an O-ring is interposed between the large-diameter portion and the cylindrical portion. The flow path switching valve according to any one of claims 1 to 5, characterized in that: When the main valve body is moved between the upper half portion and the upper valve seat and between the lower half portion and the lower valve seat, the seal surface on the main valve body side is defined as the upper valve seat and The flow path switching valve according to any one of claims 1 to 6, further comprising a ball-type seal surface separation mechanism that separates from the lower valve seat. The ball-type sealing surface separation mechanism includes a ball, a housing portion that accommodates the ball in a state in which a part of the ball protrudes in the vertical direction, and is rotatable and substantially prevented from moving. Before starting the movement of the valve body and at the end of the movement, a part of the ball protruding from the housing portion so that the seal surface on the main valve body side is not separated from the upper valve seat and the lower valve seat. And when the main valve body is moved, the ball has a dimensional shape that pushes down the upper half and rolls out while pushing up the lower half. The accommodating portion is provided at two or more locations in the upper half portion and the lower half portion, and the concave hole is located at the same position as the accommodating portion in plan view in the upper valve seat and the lower valve seat, and Front from position Flow path switching valve according to claim 7 in which the main valve body and being provided at positions spaced by a distance which moves the flow path switching. 9. The flow path switching valve according to claim 8 , wherein the concave hole is formed in a rail laid on the upper valve seat and the lower valve seat. The actuator includes a reciprocating drive cylinder having a variable volume first working chamber and a second working chamber, hermetically partitioned by a piston, into which the high pressure fluid in the main valve is introduced. While introducing the high-pressure fluid and discharging the high-pressure fluid from the second working chamber, the first stroke of moving the main valve body in one direction, and introducing the high-pressure fluid into the second working chamber, by discharging the high pressure fluid from the first working chamber, one of claims 1, characterized in that it is configured to obtain take a second step of moving the main valve body in the other direction to selectively 9 A flow path switching valve according to claim 1. A first cylinder having the first working chamber is provided on the front side of the main valve housing, and a second cylinder having the second working chamber is provided on the rear side of the main valve housing. A first pusher plate connected to the piston rod of the first cylinder is opposed to the front surface, and a second pusher plate connected to the piston rod of the second cylinder is opposed to the rear surface of the main valve body. The flow path switching valve according to claim 10 , wherein the flow path switching valve is in contact with each other. The first cylinder and the second cylinder have a common piston rod for connecting the pistons to each other, and the first push plate and the second push plate are fixed to the piston rod, A portion of the piston rod between the first push plate and the second push plate is inserted into a front and rear through hole provided in the main valve body so as to be slightly movable up and down. The flow path switching valve according to claim 11 . Switching between the first stroke and the second stroke is performed by the first working chamber and the second working chamber, and a four-way pilot valve connected to the high pressure portion and the low pressure portion of the main valve. flow path switching valve according to claim 10, wherein 12 that you are.

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