JP2019044976A - Flow passage switching valve - Google Patents

Abstract

An object of the present invention is to suppress pressure loss, reduce the amount of internal heat exchange as much as possible, effectively suppress wear of sliding parts, and improve durability and sealing performance. Provided is a flow path switching valve that can make valve leakage difficult. A cylindrical main valve housing (10) whose upper and lower openings are hermetically sealed by an upper valve seat (10A) and a lower valve seat (10B), and an upper valve seat (10A) and / or a lower valve seat (10B) in total. A main valve 5 having three ports 11 to 14 and a rectangular parallelepiped main valve body 20 movably disposed in the main valve housing 10, and a fluid pressure type for moving the main valve body 20. An actuator 7 is provided, and communication paths 31 to 34 for selectively communicating between ports are provided in the main valve body 20. By moving the main valve body 20, switching between the communicating ports is performed. Has been. [Selection diagram] Fig. 1

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 suitable for performing flow path switching in a heat pump type cooling and heating system.

  In general, heat pump type air conditioning systems such as room air conditioners and car air conditioners, in addition to compressors, outdoor heat exchangers, indoor heat exchangers, expansion valves, etc., flow path switching valves as flow path (flow direction) switching means Is equipped.

  An example of a heat pump type cooling and heating system provided with the flow path switching valve will be briefly described with reference to FIG. The heat pump type cooling and heating system 100 in the illustrated example performs switching of the operation mode (cooling operation and heating operation) by the flow path switching valve (four-way switching valve) 140, and basically, the compressor 110 and 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, the flow path switching valve 140 having the discharge side high pressure port D, the outdoor side inlet / outlet port C, the indoor side inlet / outlet port E, and the suction side low pressure port S is disposed.

  The respective devices are connected by a flow path formed by a conduit (pipe) or the like, and when the cooling operation mode is selected, the discharge side of the flow path switching valve 140 as shown by a solid arrow in FIG. The high pressure port D is in communication with the outdoor side inlet / outlet port C, and the indoor side inlet / outlet port E is in communication with the suction side low pressure port S. As a result, the refrigerant is drawn into the compressor 110, and the high temperature and high pressure refrigerant is led from the compressor 110 to the outdoor heat exchanger 120 via the flow path switching valve 140, where it exchanges heat with outdoor air and condenses. , And is introduced into the expansion valve 160 as a high-pressure two-phase refrigerant. 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 exchanges heat with the indoor air (cooling) and evaporates, and 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 inlet / outlet port E, and the outdoor side inlet / outlet port C is The refrigerant is communicated with the suction side low pressure port S, and the high temperature and high pressure refrigerant is led from the compressor 110 to the indoor heat exchanger 130, where it exchanges heat with the indoor air (heating) and condenses to form a high pressure two-phase refrigerant. Then, it 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 outdoor heat exchanger 120, where it exchanges heat with the outdoor air and evaporates, and from the outdoor heat exchanger 120 the low temperature low pressure The refrigerant is returned to the suction side of the compressor 110 via the flow path switching valve 140.

  Conventionally, as a four-way switching valve incorporated in a heat pump type cooling and heating system as described above, one having a valve main body (main valve housing) incorporating a slide type main valve body and an electromagnetic pilot valve is known. (See, for example, Patent Document 1). In the slide type flow path switching valve described in this patent document 1, the discharge side high pressure port D, the outdoor side inlet / outlet port C, the suction side low pressure port S, and the indoor side inlet / outlet port E are formed in the main valve housing. In addition, the slide type main valve body is slidably disposed in the left and right direction to create the communication state of the ports D → C and E → S or the ports D → E and C → S described above (perform flow path switching). It is present. The high pressure refrigerant on the compressor discharge side and the low pressure refrigerant on the compressor suction side are selectively introduced to the left and right of the sliding main valve body in the main valve housing via the pilot valve Two working chambers defined by a pair of left and right packed pistons are provided, and the flow is caused by sliding the sliding main valve body in the left and right direction using the pressure difference between the two working chambers. It is adapted to carry out road switching.

JP, 2009-41636, A

  In the conventional slide type flow path switching valve as described above, since the high pressure fluid (refrigerant) collides with the inner wall surface etc. in the main valve housing with a relatively small inner volume, the flow direction is largely changed. The loss is not apt to be large, and since the flow path switching is performed by sliding the slide type main valve body with a pair of left and right packed pistons, the sliding portion is easily abraded by stick slip or the like. Along with this, the durability and the sealability of the sliding portion deteriorate, and the fluid (refrigerant) is likely to leak from the sliding surface between the main valve housing and the sliding main valve body (the valve is liable to leak). .

  In addition to the above, in the conventional flow path switching valve, in particular, in the four-way switching valve used in the above-described heat pump type cooling and heating system, a state where the high temperature and high pressure refrigerant and the low temperature and low pressure refrigerant are close in the main valve housing (thin wall Since the flow is performed in a state where one sheet is separated, there is a problem that the amount of heat exchange in those main valve housings becomes large and the efficiency of the system becomes worse.

  The present invention has been made in view of the above circumstances, and it is possible to suppress pressure loss, reduce the amount of internal heat exchange as much as possible, and effectively wear the sliding portion. An object of the present invention is to provide a flow path switching valve which can be suppressed and whose durability and sealability can be improved and which can hardly leak the valve.

  In order to achieve the above object, the flow channel switching valve according to the present invention basically has a cylindrical main body in which the upper opening and the lower opening are airtightly sealed by the upper valve seat and the lower valve seat. A main valve having a valve housing, at least three ports in total 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 a main valve body is provided, and a communication passage for selectively communicating between the ports is provided in the main valve body, and communication is performed by moving the main valve body. The upper valve seat and the lower valve seat both make the surface to be sealed a flat smooth surface, and the surfaces to be sealed face each other. Placed and before Omobentai is characterized in that it is a two-divided structure of integrally movable and vertically movable upper half and a lower half portion.

  In a specific preferred embodiment, at least one communication passage capable of communicating at least one of the ports with another one is provided in the main valve body, and the main valve body is moved in one direction. Thus, flow channel switching between the communicating ports is performed.

  In another preferred embodiment, the communication passage is configured to have a U-shaped passage.

  At both ends of the communication passage, a convex portion having an annular seal surface closely contacting the opening of each port in the upper valve seat and / or the lower valve seat is preferably provided.

  In another preferred embodiment, the actuator comprises a reciprocating drive cylinder having a variable volume first working chamber and a second working chamber airtightly partitioned by a piston into which high pressure fluid in the main valve is introduced. A first stroke for moving the main valve body in one direction by introducing a high pressure fluid into the first working chamber and discharging the high pressure fluid from the second working chamber, and a high pressure fluid in the second working chamber And the second stroke for moving the main valve body in the other direction can be selectively taken by discharging the high pressure fluid from the first working chamber.

  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 push plate connected to a piston rod of the first cylinder is brought into contact with a front surface of the main valve body, and a second push plate is connected to a piston rod of the second cylinder on a rear surface of the main valve body. The pressing plate is brought into contact.

  In a further preferred aspect, the first cylinder and the second cylinder have a common piston rod connecting the respective pistons to each other, and the first pressing plate and the second pressing plate are provided on the piston rod. While being fixed, a portion of the piston rod between the first pressing plate and the second pressing plate is inserted so as to be able to move slightly up and down through holes formed in the main valve body. .

  In another preferred embodiment, a four-way pilot valve connected to the first operating chamber and the second operating chamber, and the high pressure portion and the low pressure portion of the main valve, switches between the first stroke and the second stroke. To be done by

  In the flow path switching valve according to the present invention, since all the ports are provided on 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 fluid can be made to flow straight from the port directly below or above as a straight passage substantially the same as the diameter of each port from the beginning to the end (passage diameter), so the main valve (main valve body Can effectively suppress the occurrence of pressure loss within the In addition, the remaining communication path can be made to not change the effective passage area from the start to the end by providing a guide of a specific shape in the bend (the part where the flow direction changes), etc. This makes it difficult to generate a flow, thereby suppressing expansion and contraction of the fluid in the communication passage and reducing the resistance to the fluid flowing in the communication passage, so that the fluid can flow smoothly and the pressure loss As a whole, the pressure loss can be considerably reduced as compared with the conventional flow path switching valve.

  Also, the main valve body receiving high pressure is in the form of a rectangular parallelepiped, and a communication passage consisting of a straight through passage is provided therein, and U-shaped communication passages are provided above and below the inside, so the overall structure is simple. While being able to be used, the flow channel switching balance also becomes good, and further sufficient strength and durability can be ensured.

  In addition, the upper valve seat and the lower valve seat, which are the surfaces to be sealed, that is, the portions to which the main valve body (upper half and lower half) are in sliding contact when switching the flow path, are flat. It is possible to make the surface to be sealed a flat smooth surface (easily increase the surface accuracy), which also makes it possible to significantly improve the sealing performance.

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

  Further, the main valve body is divided into an upper half and a lower half, and the upper half and the lower half can be moved up and down independently, respectively, and between the upper half and the lower half By disposing an urging means such as a compression coil spring, the upper half and the lower half can be pressed against the valve seat surface by the urging force. In addition, by projecting the convex portions on the main valve body side (both ends of each communication passage) and using the end face as an annular seal surface, the area of the portion in contact with the valve seat surface can be minimized. Contact pressure can be increased. By these, sufficient sealing performance can be ensured and valve leakage can be suppressed 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 / high pressure refrigerant and a low temperature / 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 they are separated and installed, the amount of heat exchange in the main valve housing compared to the conventional one in which the high-temperature and high-pressure refrigerant and the low-temperature and low-pressure refrigerant flow in close proximity (a thin wall is separated). Can be significantly reduced, which also has the effect of improving the efficiency of the system.

  Also, as the actuator is a hydraulic type that reciprocates the main valve body using the differential pressure between the high pressure fluid and the low pressure fluid supplied into the main valve, the main valve body may be an electromagnetic type or an electric type. Compared to the case of direct movement with the actuator of the above, cost reduction, reduction of power consumption, energy saving and the like can be achieved.

  The subject, composition, and an effect other than the above-mentioned are clarified by the following embodiments.

The top view which shows the state in which the main valve body is in a 1st movement position in one Example of the flow-path switching valve concerning this invention. The top view which shows the state in which the main valve body is in a 2nd movement position in one Example of the flow-path switching valve concerning this invention. Sectional drawing according to the AA arrow of FIG. Sectional drawing according to the AA arrow of FIG. Sectional drawing according to the BB arrow of FIG. Sectional drawing according to the BB arrow of FIG. Sectional drawing according to the CC arrow line of FIG. (A) is a fragmentary sectional view according to the DD arrow line of FIG. 3, (B) is a fragmentary sectional view according to the EE arrow line of sight of (A). The expanded sectional view which is provided to the structure and operation description of the seal surface separation mechanism provided in the flow-path switching valve of the said Example. 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 equipped. 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 equipped. The 10-way pilot valve shown by FIG. 10 is shown, (A) is an expanded sectional view each showing the time of electricity supply OFF, and (B) each showing the time of electricity supply ON. BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows an example of a heat pump type air conditioning system.

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

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

  In the present specification, descriptions representing positions, directions such as upper and lower, right and left, front and rear, etc. are provided for convenience according to the drawings to avoid complicated explanation, and are actually incorporated into a heat pump type air conditioning system etc. It does not necessarily indicate the position or direction in the closed state.

  Further, in each drawing, the gap formed between the members, the separation distance between the members, and the like are large in comparison with the dimensions of the respective constituent members in order to facilitate understanding of the invention and for convenience in drawing. Or it may be drawn small.

  The flow path switching valve 1 of the illustrated embodiment is a sliding four-way switching valve, and is used as, for example, the four-way switching valve 140 in the heat pump type cooling and heating system 100 shown in FIG. 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 back and forth (hereinafter may be abbreviated as back and forth movement) and capable of moving up and down; And a hydraulic actuator 7 having a four-way pilot valve 80 (see FIGS. 10 and 11 described later).

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

  At the left and right of the upper valve seat 10A, a first port 11 and a second port 12 consisting of a pipe joint are vertically provided at predetermined intervals J, and at the left and right of the lower valve sheet 10B, a predetermined interval J is provided. The 3rd port 13 and the 4th port 14 which consist of joints are vertically provided. Here, the first port 11 and the third port 13 and the second port 12 and the fourth port 14 are disposed at the same position in plan view.

  In the present embodiment, for example, the first port 11 is a discharge high-pressure port D connected to the compressor discharge side when incorporated in the heat pump type cooling and heating system 100 as shown in FIG. 12 is an indoor side inlet / outlet port E connected to the indoor heat exchanger, the third port 13 is an outdoor side inlet / outlet port C connected to the outdoor heat exchanger, and the fourth port 14 is connected to the compressor suction side And 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 right and left rails 44, 44 are provided for the convenience of moving the main valve body 20 back and forth The main valve body contact surface) is laid 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 split configuration of an upper half 20A and a lower half 20B of a short rectangular column. Specifically, the upper half 20A is constituted by the relatively thick first layer member 21 and the 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 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 (of the second layer member 22) and the lower half 20B (of the third layer member 23), as shown in FIG. 8, they are biased away from each other. Four compression coil springs 29 as biasing means are contracted. The four compression coil springs 29 are loaded in the four spring housing holes 23 h provided near the four corners on the upper surface side of the third layer member 23 in a state in which a part thereof is protruded upward.

  When the flow path is switched, the main valve body 20 is reciprocated in the front-rear direction by an actuator 7 described later, and the first movement position as shown in FIGS. 1 and 5 and the rear from the first movement position The second movement position as shown in FIGS. 2 and 6 can be selectively taken by moving it by a predetermined distance L (see FIGS. 1 and 2).

  In the main valve body 20, when the first movement position is taken, the linear first communication passage 31, the second port 12, and the fourth port 14 are communicated with each other, which brings the first port 11 and the third port 13 into communication. U-shaped third communication passage 33 and third port for communicating the first port 11 with the second port 12 when the second communication passage 32 is provided and the second movement position is taken. A U-shaped fourth communication passage 34 is provided to communicate the valve 13 and the fourth port 14 (details will be described later).

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

  The first cylinder 50A has a cylinder portion 51 provided straddling the front lid member 10D (the thick portion thereof) and the front projection portion, and in the cylinder portion 51, a piston 52 with a packing 53 is provided in the front-rear direction A variable volume first working chamber 55A which is slidably inserted and is airtightly sealed by the piston 52 with the packing 53 is formed.

  The second cylinder 50B has a cylinder portion 51 provided on the rear projection of the main valve housing 10, and in this cylinder portion 51, the piston 52 with the packing 53 is inserted slidably in the front-rear direction A variable volume second working chamber 55B hermetically sealed by the piston 52 with the packing 53 is formed.

  The first cylinder 50A and the second cylinder 50B have a common piston rod 54 connecting the respective pistons 52, 52 to each other. A rectangular plate-shaped first pressing plate 58A brought into contact with the front surface is fixed, and a rectangular plate-shaped second pressing member brought into contact with the rear surface of the main valve body 20 near the rear end of the middle portion thereof The plate 58B is fixed. The first pressing plate 58A and the second pressing plate 58B are sized to be able to press substantially the entire front and rear surfaces of the main valve body 20, respectively.

  Further, a portion between the first pressing plate 58A and the second pressing plate 58B in the piston rod 54 is provided in a substantially central portion (third layer member 23) of the main valve body 20. A slight relative vertical movement is inserted into the through hole 60.

  The first push plate 58A and the second push plate 58B may be fixed to the piston rod 54 by, for example, referring to FIG. 7 in addition to FIGS. 5 and 6. A slit-like notch 61 whose lower surface is opened below the central portion of the 58A and the second pressing plate 58B is formed, and a pair of left and right fitting grooves 62 are formed on the piston rod 54 by both left and right parallel chamfering. The left and right edges of the slit-like notch 61 are pushed into the fitting groove 62 from the top in such a manner that the upper end thereof contacts the piston rod 54, and then fixed by welding or the like as necessary. Ru.

  The first working chamber 55A of the first cylinder 50A is provided with a first inlet / outlet port 56A for introducing and discharging high pressure fluid to and from the first working chamber 55A, and a second working chamber of the second cylinder 50B. The 55B is provided with a second inlet / outlet port 56B for introducing and discharging a high pressure fluid to and from the second working chamber 55B. The first inlet / outlet port 56A and the second inlet / outlet port 56B open at a portion (on the left side) near the projecting end of the cylinder portion 51.

  Here, the main valve body 20 is in the first movement position where the first pushing plate 58A is in contact with the front lid member 10D and the forward movement thereof is blocked (FIGS. 1 and 5) The second push plate 58B is in contact with the rear wall 10E of the box portion 10C and is in the second movement position where its backward movement is blocked (FIGS. 2 and 6). It is supposed to get you.

  In other words, the front lid member 10D and the rear wall 10E serve as a stopper for stopping the back and forth movement of the main valve body 20, and 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 portion 10C when the main valve body 20 is in the first movement position (FIG. 1) Are both L, and 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 are both L in the main valve body 20. It is assumed.

  While the main valve body 20 is in the first movement position (FIGS. 1 and 5), the 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 through the 2 inlet / outlet port 56B, the pistons 52, 52 of the first cylinder 50A and the second cylinder 50B move rearward, and accordingly, the first valve plate 58A causes the main valve body 20 to move to the first position. The second push plate 58B abuts against the rear wall 10E of the box-shaped portion 10C to prevent its rearward movement. The movement distance at this time is L, and the position at this time is the second movement position (movement from the first movement position to the second movement position is referred to as a backward movement stroke).

  On the other hand, when the main valve body 20 is in the second movement position (FIGS. 2 and 6), the high pressure fluid is introduced to 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, 52 of the first cylinder 50A and the second cylinder 50B move forward, and the main valve body 20 is moved by the second push plate 58B accordingly. Is pushed forward from the second movement position, and eventually the first push plate 58A contacts the front lid member 10D to prevent its forward movement. The movement distance at this time is L, and the position at this time is the first movement position (movement from this second movement position to the first movement position is referred to as a forward movement stroke).

  Next, the configuration of the main valve body 20 and the first to fourth communication passages 31 to 34 provided thereon will be described 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. And the bore diameter is substantially the same as the bore diameter of each of the ports 11 to 14, and the effective passage area (passage diameter) of each passage portion. The total length of the ports 11 to 14 is substantially the same.

  In the first layer member 21 constituting the upper portion of the upper half portion 20A of the main valve body 20, two straight penetrations are provided with a predetermined distance J (the same as the distance 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 two horizontal holed passage portions 21C and 21D connected by the horizontal holes 21E having a linear shape in plan view are provided, whose lower surface openings are closed by the second layer member 22. The horizontal holed passage portions 21C and 21D are disposed with a predetermined distance J on the left and right, and the two are combined to form a U-shaped third communication passage 33. The configuration of the third communication passage 33 and the function and effect will be described in detail later. The separation distance between the straight through passage parts 21A and 21B and the horizontal holed passage parts 21C and 21D is equal to the movement distance L from the first movement position to the second movement position of the main valve body 20 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 the main valve body 20 is moved to the second movement position by moving it backward by the distance L, the upper surface openings of the straight through passage portions 21A and 21B are closed by the upper valve sheet 10A, and the passage portion 21C with a horizontal hole, The top opening 21D is located directly below the first port 11 and the second port 12.

  Conversely, when the main valve body 20 is moved forward from the second movement position by the distance L, the main valve body 20 moves to the first movement position, and the upper surface openings of the horizontal holed passage portions 21C, 21D While being closed by the upper valve seat 10A, the upper surface openings of the straight through passage portions 21A, 21B are positioned directly below the first port 11 and the second port 12.

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

  Further, in the third layer member 23 constituting the upper portion of the lower half portion 20B of the main valve body 20, two straight through passage portions are positioned so as to be located directly below the straight through passage portions 22A, 22B of the second layer member 22. 23A and 23B are provided.

  Similar to the first layer member 21, the fourth layer member 24 constituting the lower portion of the lower half 20B of the main valve body 20 is provided with two straight through passage portions 24A and 24B at predetermined intervals J on the left and right. There are also provided two lateral holed passage portions 24C and 24D connected by a straight hole 24E in a plan view, whose upper surface opening is closed by the third layer member 23. The horizontal holed passage portions 24C and 24D are disposed at predetermined intervals J on the left and right, and the two are combined to form a U-shaped fourth communication passage 34. The separation distance between the straight through passage parts 24A and 24B and the horizontal holed passage parts 24C and 24D is equal to the movement distance L from the first movement position to the second movement position of the main valve body 20 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 directly above the third port 13 and the fourth port 14, and the main valve body 20 is moved to the first movement position. When the main valve body 20 is moved to the second movement position by being moved backward by a predetermined distance L from the valve, the lower surface openings of the straight through passage portions 24A, 24B are closed by the lower valve sheet 10B, and The lower surface openings of the portions 24C and 24D are located directly above the third port 13 and the fourth port 14.

  Conversely, when the main valve body 20 is moved forward from the second movement position by the distance L, the main valve body 20 moves to the first movement position, and the lower surface openings of the horizontal holed passage portions 24C and 24D While being closed by the lower valve seat 10B, the lower surface openings of the straight through passage portions 24A, 24B are positioned 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 sheet 10A and the lower valve sheet 10B are provided at both ends of the communication passages 31, 32, 33 and 34 described above. A convex portion 36 having an annular seal surface closely contacting around the openings 14 to 14 is protruded.

  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. The following measures have been taken to ensure sealability. That is, to describe the first communication passage 31 as a representative, the stepped large diameter portion 22c is formed in the lower portion of the straight through passage portion 22A of the second layer member 22 constituting the first communication passage 31, A cylindrical portion 23c slidably inserted in the large diameter portion 22c is extended 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 by welding or the like to the lower end of the large diameter portion 22 c in order to prevent the O-ring 28 from falling off. The second communication passage 32 has a similar configuration.

  In addition to the above, in the present embodiment, the main valve body 20 is disposed between the first layer member 21 and the upper valve sheet 10A of the main valve body 20 and between the fourth layer member 24 and the lower valve sheet 10B. When moving, the ball type seal surface separation mechanism 45 which separates the seal surface on the main valve body 20 side from the valve seat surface 17 of the upper valve seat 10A and the lower valve seat 10B is provided.

  The ball type seal surface separation mechanism 45 is provided between the first layer member 21 and the upper valve seat 10A, and as shown in a representative example in FIG. In a state in which part of the main valve body 20 is rotatably and partially blocked in a state in which part of the main valve body 20 protrudes in the vertical direction, and before the main valve body 20 starts moving and at the time of moving end, the main valve When the main valve body 20 starts moving (a flow is started when the main valve body 20 starts to move) (a flow is started when the main valve body 20 is moved). At the start of the path switching), the ball 46 is provided with a truncated cone-like concave hole 48 sized and rolled out 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 housing portion 47 is fixed to the circular hole 47a and the circular hole 47a by press-fitting or the like, and the upper part is narrowed. It is comprised by the cylindrical retaining metal fitting 47b.

  The housing portion 47 in which the ball 46 is housed is the movement of the main valve body 20 described above in the front and back 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 recessed hole 48 is provided at a distance twice as large as the distance L, and the recessed portion 48 is the accommodation portion in plan view of the left and right rails 44 and 44 laid on the upper valve seat 10A and the lower valve seat 10B. A total of four positions are provided at the same position as the position 47 and a position separated from the position by the moving distance L (see FIGS. 1 and 2).

  The rails 44 are not necessarily required, and the recessed holes 48 may be provided directly on the upper valve seat 10A and the lower valve seat 10B. In the present embodiment, the rails 44 provided with the recessed holes 48 at the four places are prepared in advance as described above, and the long grooves in which the rails 44 are embedded when the box-shaped portion 10C is molded are formed (gold The long groove forming portion of the mold is made to be able to be pulled forward after molding), a method of fitting and fixing the rail 44 with the concave hole 48 in the long groove after molding, or a mold of the box portion 10C During molding, the rail 44 with the recessed hole 48 is insert-molded and integrated.

  In the above-described ball type seal surface separation mechanism 45, before the start of movement of the main valve body 20 and at the time of completion of movement, as shown in FIG. 9A, the balls 46 in the concave hole 48 of the upper valve seat 10A. Some are stuck. The amount of fitting (height from the valve seat surface 17 of the upper valve seat 10A to the top of the ball 46) is h. When the main valve body 20 is started to be moved from this state, the accommodation portion 47 also starts to move, and the ball 46 is accordingly moved to the main valve body 20 (upper half 20A) as shown in FIG. 9 (B). Is rolled out from the recessed hole 48 while being pushed down against the biasing force of the compression coil spring 29 compressed between the upper half 20A and the lower half 20B. Thereby, 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 of depression of the main valve body 20 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 recessed hole 48, so the main valve body 20 (upper half 20A) is pushed up by the biasing 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 understood from the above description, when the main valve body 20 assumes the first movement position, the first communication passage 31 communicating the first port 11 and the third port 13 is the straight through passage portion 21A, 22A, 23A, and 24A, and the second communication passage 32 for communicating the second port 12 with the fourth port 14 is a straight through passage portion 21B, 22B, 23B, and 24B. It will be a straight passage configured.

  On the other hand, when the main valve body 20 assumes the second movement position, the third communication passage 33 for communicating the first port 11 with the second port 12 is provided in the upper half 20A of the main valve body 20. A fourth communication passage 34 is formed in the lower half 20B of the main valve body 20. The fourth communication passage 34 is a U-shaped passage configured by the horizontal holed passage portions 21C and 21D and causes the third port 13 and the fourth port 14 to communicate with each other. It becomes a U-shaped passage which is composed of the lateral holed passage portions 24C and 24D.

  Here, as shown in FIG. 4, between the lateral holed passage portions 21C, 21D forming the third communication passage 33 and between the lateral holed passage portions 24C, 24D forming the fourth communication passage 34, as shown in FIG. The guide portions 20G which are relatively long in the left-right direction and in which the corner portions on the inner end side bulging are provided on the 21E and 24E sides are provided. The guide portion 20G can suppress the generation of a swirl at a portion where the fluid (refrigerant) bends in a U-shape, and the effective passage area (passage diameter) of the lateral holes 21E and 24E and the diameters of the ports 11 to 14 Since the third communication passage 33 and the fourth communication passage 34 have a substantially constant passage diameter over the entire length, the fluid expansion in the third communication passage 33 and the fourth communication passage 34, There is no contraction, so pressure loss can be reduced.

  Temporarily, the upper half 20A (third communication passage 33) of the main valve body 20 is divided into 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) in the case where the upper half 20A and the lower half 20B are respectively manufactured as a single piece by molding instead of being formed by two members of the third layer member 23 and the fourth layer member 24. Since the horizontal holes 21E and 24E of the communication passage 33 and the fourth communication passage 34 form undercuts, the third communication passage 33 and the fourth communication passage 34 have to be in a wedge shape without the guide portion 20G. As a result, the generation of the eddy flow can not be suppressed, and the passage diameter can not be made substantially constant, so that the pressure loss becomes large.

  As described above, in the flow path switching valve 1 of the present embodiment, the first communication passage 31 is performed by performing the backward movement stroke in which the main valve body 20 is moved backward from the first movement position by the distance L. Between the communicating ports 11-13 and between the ports 12-14 communicating with the second communication passage 32, between the ports 11-12 communicating with the third communication passage 33 and between the ports 13-14 communicating with the fourth communication passage 34 Between the ports 11-12 communicated by the third communication passage 33 by performing a forward movement stroke in which the main valve body 20 is moved forward from the second movement position by the distance L. The flow paths are switched between the ports 13-14 communicated by the fourth communication passage 34 and between the ports 11-13 communicated by the first communication passage 31 and between the ports 12-14 communicated by the second communication passage 32. That.

  When the flow path switching valve 1 of the present embodiment is incorporated into a heat pump type cooling and heating 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 is the indoor side inlet / outlet port E connected to the indoor heat exchanger, the third port 13 is the outdoor side inlet / outlet port C connected to the outdoor heat exchanger, the fourth port 14 is the compressor suction The suction side low pressure port S is connected to the side.

  Then, when performing the cooling operation, the main valve body 20 is made to assume the first movement position. As a result, as shown by the white arrow in FIG. 3, the high pressure refrigerant from the compressor is discharged from the discharge side high pressure port 11 (D) to the linear first communication passage 31 to the outdoor outside inlet / outlet port 13 (C). As it flows, the low pressure refrigerant from the indoor heat exchanger flows from the indoor side inlet / outlet port 12 (E) → the linear second communication passage 32 → the suction side low pressure port 14 (S).

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

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

  In addition, as the U-shaped third communication passage 33 and the fourth communication passage 34 are provided with the guide portion 20G having a specific shape as described above, the effective passage area can be prevented from significantly changing from the start end to the end. While making it difficult to generate a swirl at the U-shaped bent portion, expansion and contraction of the fluid in the communication passages 33, 34 can be suppressed, and the resistance to the fluid flowing in the communication passages 33, 34 is reduced. As a result, the fluid can flow smoothly and the pressure loss can be reduced, and in total, the pressure loss can be considerably reduced as compared with the conventional flow path switching valve.

  Further, the main valve body 20 receiving high pressure is in the form of a rectangular parallelepiped, and communication passages 31 and 32 consisting of straight through passages are provided therein, and U-shaped communication passages 33 and 34 are provided on the upper and lower sides thereof. Therefore, the entire structure can be simplified, and the flow path switching balance can be improved, and further, sufficient strength and durability can be ensured.

  In addition, the upper valve sheet 10A and the lower valve sheet 10B which are the surfaces to be sealed, that is, the portions to which the main valve body 20 (the upper half 20A and the lower half 20B) slide when switching the flow path Therefore, the surface to be sealed can be made flat and smooth (it is easy to increase the surface accuracy), which also makes it possible to greatly improve the sealing performance.

  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, piping can be easily managed, and the substantial occupied space including the piping can be reduced. it can.

  Further, the main valve body 20 is divided into an upper half 20A and a lower half 20B so that the upper half 20A and the lower half 20B can move up and down independently, and the upper half Since the compression coil spring 29 is compressed 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 at the valve seat surface 17 of the upper valve seat 10A. While being pressed around each port 11, 12, the lower half 20B is pushed down so that its sealing surface is pressed around each port 13, 14 in the valve seat surface 17 of the lower valve seat 10B.

  In this case, since the convex portion 36 is provided on the main valve body 20 (upper half 20A and lower half 20B) side and the end face thereof is the annular seal surface 37, the part that contacts the valve seat surface 17 The surface area of the contact surface is minimized, so the contact pressure is increased. By these synergetic effects, sufficient sealing performance can be secured, and valve leakage can be effectively suppressed.

  Furthermore, in the present embodiment, the upper half 20A of the main valve body 20 is pushed down by the ball type seal surface separation mechanism 45 when the main valve body 20 is moving (during flow path switching). 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, 17 of the upper valve seat 10A and the lower valve seat 10B, almost no sliding friction occurs Therefore, stick-slip and the like can be prevented, abrasion of the sliding portion can be greatly suppressed, and further, since the abrasion is suppressed, sealing performance can be improved and valve leakage can be further effectively suppressed.

  Further, in the four-way switching valve having the conventional slide type main valve body as shown in Patent Document 1, the flow passage opening area between the high pressure pipe D and the low pressure pipe S changes rapidly when the flow path is switched, An abnormal noise (switching noise) is generated when the high pressure refrigerant enters the low pressure pipe at a stretch. In order to prevent this abnormal noise, the frequency of the compressor is gradually decreased on the air conditioning and heating system side so that the differential pressure due to the pressure difference between the high pressure pipe D and the low pressure pipe S becomes an acceptable differential pressure. It was necessary to switch the flow path from In the flow path switching valve 1 of the present embodiment, the main valve body is floated from the valve seat surface by the ball type seal surface separation mechanism 45 after the insertion amount h is increased, and then switching is performed. As a result, the opening area of the flow passage between the high pressure pipe D and the low pressure pipe S does not change rapidly, and hence the generation of the above-mentioned abnormal noise can be suppressed. In addition, the degree of reduction of the frequency of the compressor at the time of flow path switching can be made smaller than that of the cooling and heating system using the four-way switching valve of Patent Document 1 by changing the fitting amount h appropriately. It is also possible to switch the flow path without lowering the

  In addition to the above, when the flow path switching valve 1 of 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 / heating system, each communication path 31 to 34 is a main valve body Since they are provided relatively widely apart within 20, compared with 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 (in a state where one thin wall is separated), The amount of heat exchange in the valve housing 10 can be greatly reduced, and thus the effect of improving the efficiency of the system can be obtained.

  In the above embodiment, the upper half 20A 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. Alternatively, the upper half 20A and the lower half 20B may be manufactured as one unit from the beginning by a 3D printer or the like, and further, the upper half 20A and the lower half 20B may be manufactured separately. The lower half 20B may be made as one piece, that is, the main valve body 20 may be made as one member.

  Moreover, although the four-way switching valve 1 was illustrated in the said Example, the flow-path switching valve concerning this invention is not restricted to a four-way switching valve, It is applicable also to a three-way switching valve etc. In the case of the three-way switching valve, in the flow channel switching valve (four-way switching valve) 1 of the above embodiment, for example, the upper half 20A is manufactured as an integral body from the beginning (there is no need to form a U-shaped communication passage ), The second port 12 provided in the main valve housing 10 is eliminated, and the straight through passages 21B, 22B, 23B, 24B, which constitute the second communication passage 32 and the third communication passage 33, and the passage portion with a lateral hole 21C and 21D and the portion associated therewith are eliminated, and the communication passage is a linear first communication passage which causes the first port 11 and the third port 13 to communicate with each other when the main valve body 20 assumes the first movement position. 31 and the U-shaped fourth communication passage 34 that allows the third port 13 and the fourth port 14 to communicate with each other when the main valve body 20 takes the second movement position.

  When the three-way switching valve is used in the above-described heat pump type air conditioning system, two three-way switching valves are used to act as a four-way switching valve, or switching of refrigerant or cold air / warm air supply destination (for example, Used for switching 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, 50B. The first port 11 (the discharge side high pressure port D, which may be referred to as the high pressure port 11) which is the high pressure part of the valve 5 and the fourth port 14 (the suction side low pressure port S which is the low pressure part) , And may be referred to as “electromagnetic four-way pilot valve 80” connected thereto.

  The four-way pilot valve 80 is mounted laterally on the rear of the left side of the box-shaped portion 10C of the main valve housing 10 via a U-shaped proximal end attachment 65 and a reception attachment 66 (attachment The details of the tools 65, 66, etc. 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 of the other drawings in FIG. 12) 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, and a plunger 85 disposed opposite to the suction element 84 are provided. ing. The plunger 85 is slidably fitted in a cylindrical guide pipe 86 in which one end (upper end in FIG. 12, the same applies hereinafter) is disposed between the coil 82 a and the suction element 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-equipped cover member 81 having a thin tube insertion hole is airtightly sealed by welding, brazing, caulking or the like at the lower end side opening The region enclosed by the lid member 81, the plunger 85 and the guide pipe 86 is a valve chamber 88.

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

  A mounting opening 86a is formed between the lower end of the plunger 85 and the lid member 81 in the guide pipe 86, and an inner end surface of the mounting opening 86a is a valve seat (valve seat) 92. Surface of the plunger 85 is a stopper surface for stopping the movement of the plunger 85 in the direction away from the suction element 84, and the outer periphery of the end of the valve seat block 83 opposite to the valve seat is rectangular. It is airtightly sealed and joined. The side opposite to the valve seat side of the valve seat block 83 is a cylindrical surface along the outer peripheral surface of the guide pipe 86, and around the junction of the cylindrical surface of the valve seat block 83 and the mounting opening 86 a of the guide pipe 86 Is closely attached to a mounting seat 66a (see also FIG. 11) of the receiving fixture 66 which will be described later (see also FIG. 11) and is hermetically joined by welding or the like, whereby the four-way pilot valve 80 is received fixture It is attached and fixed to the main valve housing 10 via 66 and a proximal end attachment 65.

  At the end opposite to the suction element 84 side of the plunger 85, the valve body holder 90 holding the valve body 91 slidably in the thickness direction at the free end side crimps the wide proximal end 96, etc. It is attached and fixed by. A leaf spring 94 is attached to the valve body holder 90 for biasing the valve body 91 in a direction (thickness direction) to press the valve seat 92. 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. The recessed part 93 dented in the thickness direction is provided. In the valve seat block 83, one end of the thin tube 95a communicates with only the port a, and one end of the thin tube 95b communicates with only the port b so as to communicate only with the port b. Are inserted respectively. Further, one end portion of the thin tube 95 d is attached to the lid member 81.

  On the other hand, as shown in FIGS. 10 and 11, the capillaries 95a, 95b, 95c and 95d are drawn along the outer surface of the main valve housing 10, and the other end of the capillary 95a is The other end of the capillary 95b is connected to the low pressure port 14, and the other end of the capillary 95c is connected to the first working chamber 55A via the first input / output port 56A of the one cylinder 50A. It is connected to the 2nd operation room 55B via 2 entrance-and-exit port 56B. Further, the other end of the thin tube 95 d is connected to the high pressure port 11.

  Next, the proximal end attachment 65 and the receiving attachment 66 for attaching the four-way pilot valve 80 to the rear of the left side of the box-shaped portion 10C of the main valve housing 10 will be described. The proximal end attachment 65 has a rectangular flat plate-like longitudinal side 65a and upper and lower horizontal sides 65b and 65c, and the (peripheral part) of the vertical side 65a is a box-shaped portion 10C of the main valve housing 10. It is fixed to the rear of the left side by welding or the like. Further, through holes of a set screw 70 to be connected and fixed to the receiving side attachment 66 are formed in the side portions 65b and 65c, respectively, and the inner side of the through hole in the lower side portion 65c is formed. A burring portion 65d on which the set screw 70 is screwed is formed at the outer peripheral edge portion.

  On the other hand, the receiving attachment 66 is formed in a reverse U-shape like that of the proximal end attachment 65 turned left and right, and the cross section along the outer peripheral surface of the guide pipe 86 of the four-way pilot valve 80 An arc-shaped mounting seat 66a (see also FIG. 11) is provided, and rectangular flat side portions 66b and 66c are provided at the upper and lower ends of the mounting seat 66a. The distance between the lateral sides 66b and 66c of the receiving fixture 66 is the same as that of the proximal fixture 65, but the width of the lateral sides 66b and 66c is wider than that of the proximal fixture 65, The upper and lower horizontal sides 66b and 66c of the receiving fixture 66 are located below the upper and lower horizontal sides 65b and 65c of the proximal fixture 65, respectively. Further, through holes of a set screw 70 to be connected and fixed to the proximal end attachment 65 are formed in the side portions 66b and 66c, respectively, and the inner side of the through hole in the upper side portion 66b is formed. A burring portion 66d on which the set screw 70 is screwed is formed at the outer peripheral edge portion.

  When attaching the four-way pilot valve 80 to the main valve housing 10, as described above, the periphery of the joint between the valve seat block 83 and the attachment opening 86a of the guide pipe 86 is welded to the attachment seat 66a of the receiving attachment 66 After joining, the receiving fitting 66 is fixed to the proximal fitting 65 with the setscrews 70, 70.

  In the four-way pilot valve 80 configured as above, when the power is off, as shown in FIG. 12A, the lower end of the plunger 85 contacts the valve seat block 83 by the biasing force of the plunger spring 87. Is pushed down to the position where In this state, the valve body 91 is located on the port a and the port b, and the recess 93 communicates the port a and the port b, and the port c and the valve chamber 88 communicate with each other. Is introduced into the second working chamber 55B via the capillary 95d → valve chamber 88 → port c → capillary 95c → second inlet / outlet port 56B, and the high pressure fluid in the first operating chamber 55A is introduced into the first inlet / outlet port 56A → capillary 95a. → Port a → recessed portion 93 → port b → capillary 95 b → low pressure port 14 and discharged.

  On the other hand, at the time of energization ON, as shown in FIG. 12B, the plunger 85 is drawn to the position where the upper end thereof contacts the suction child 84 by the suction force of the suction child 84. At this time, the valve body 91 is located on the port b and the port c, and the recess 93 makes the port b and the port c communicate with each other and the port a and the valve chamber 88 communicate with each other. The high pressure fluid in the second working chamber 55B is introduced into the first working chamber 55A through the thin tube 95d → valve chamber 88 → port a → the thin tube 95a → first inlet / outlet port 56A, and the second inlet / outlet port 56B → capillary 95c → It flows from the port c to the recess 93 to the port b to the thin tube 95b to the low pressure port 14 and is discharged.

  Therefore, when the energization is switched from the energization OFF to the energization ON, 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 switched from the energization ON to the energization OFF, 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.

  As described above, in the flow path switching valve 1 of the present embodiment, in addition to the effects by the configuration of the main valve 5 described above, the following effects can be obtained.

  That is, by switching ON / OFF the energization to the electromagnetic four-way pilot valve 80, the main valve body 20 is reciprocated by utilizing the differential pressure between the high pressure fluid and the low pressure fluid flowing in the main valve 5. Since 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 into the heat pump type cooling and heating system but also into other systems, devices and devices.

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

DESCRIPTION OF SYMBOLS 1 flow-path switching valve 5 main valve 7 actuator 10 main valve housing 10A upper side valve seat 10B lower side 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 portion 20B Lower half portion 21 First layer member 22 Second layer member 23 Third layer member 24 Fourth layer member 29 Compression coil spring 31 First communication passage 32 Second communication passage 33 third Communication passage 34 Fourth communication passage 36 Convex part 44 Rail 45 Ball type seal surface separation mechanism 46 Ball 47 Housing part 48 Concave hole 50 Reciproc drive cylinder 50A First cylinder 50B Second cylinder 55A First working chamber 55B Second working chamber 56A First in / out port 56B Second in / out port 58A First push plate 58B Second push 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 Ports (four-way pilot valve)
95a, 95b, 95c, 95d Tubular D Discharge-side high-pressure port S Intake-side low-pressure port C Room outside inlet / outlet port E Inside inlet / outlet port

Claims (8)

A total of at least three cylindrical main valve housings whose upper and lower openings are hermetically sealed by upper and lower valve seats, and at least the upper and lower valve seats are provided. A main valve having a main port, a main valve body movably disposed in the main valve housing, and a hydraulic actuator for moving the main valve body,
A communication passage is provided in the main valve body for selectively communicating between the ports, and by moving the main valve body, the communication ports are switched.
The upper valve seat and the lower valve seat both have flat surfaces to be sealed, and the surfaces to be sealed are disposed opposite to each other.
The flow control valve according to claim 1, wherein the main valve body is divided into two parts, an upper half and a lower half which can move together and can move up and down.   At least one communication passage which allows at least one of the ports to communicate with another one is provided in the main valve body, and by moving the main valve body in one direction, between the ports in communication with each other. A flow path switching valve according to claim 1, characterized in that the flow path switching is performed.   The flow passage switching valve according to claim 1 or 2, wherein the communication passage is configured to have a U-shaped passage.   At both ends of the communication passage, projections having an annular sealing surface closely contacting the openings of the ports of the upper valve seat and / or the lower valve seat are provided in a protruding manner. The flow-path switching valve as described in any one of to 3.   The actuator includes a reciprocating drive cylinder having a first working chamber and a second working chamber which are airtightly partitioned by a piston, into which high pressure fluid in the main valve is introduced, and in the first working chamber A first stroke for moving the main valve body in one direction by introducing a high pressure fluid and discharging the high pressure fluid from the second working chamber, introducing the high pressure fluid into the second working chamber, and 5. A system according to any one of claims 1 to 4, characterized in that a second stroke for moving said main valve body in the other direction can be selectively taken by discharging high pressure fluid from the first working chamber. The flow path switching valve according to any one of the preceding claims.   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. The first pressing plate connected to the piston rod of the first cylinder is brought into contact with the front surface, and the second pressing plate connected to the piston rod of the second cylinder is paired to the rear surface of the main valve body. The flow path switching valve according to claim 5, characterized in that the flow path switching valve is in contact.   The first cylinder and the second cylinder have a common piston rod that interconnects the respective pistons, and the first pressing plate and the second pressing plate are fixed to the piston rod, A portion of the piston rod between the first pressing plate and the second pressing plate is inserted in the front and rear through holes provided in the main valve body so as to be able to move slightly up and down. The flow path switching valve according to claim 6.   Switching between the first stroke and the second stroke is performed by a 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. The flow passage switching valve according to any one of claims 5 to 7, characterized in that:

Images