Slide-type switching valve and refrigeration cycle system

Abstract

To provide a slide type switching valve and a refrigeration cycle system that can improve operation stability and durability.SOLUTION: A slide type switching valve 2 comprises: a valve housing 20; a cylindrical piston 50 housed in the valve housing 20, and to be moved in the direction of an axis X; a connection member 40 to which the piston 50 is fixed by a fixing screw 61; a valve element 70 held by the connection member 40; a valve seat part 23 on which the valve element 70 is slid; and a plurality of valve ports provided in the valve seat part 23. The connection member 40 comprises: a main body part 41 holding the valve element 70; and a piston fixing part 45 provided with a fixing surface 46 protruding on one side in a height direction Z intersecting with the direction of the axis X from the main body part 41, and extending continuously in a width direction Y. The piston 50 is fixed to the connection member 40 by the fixing screw 61 while being in contact with the fixing surface 46.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a slide type switching valve and a refrigeration cycle system.

Background Art

[0002] Conventionally, a slide type switching valve (slide valve) that partitions a space in a cylindrical valve housing by a piston housed in the valve housing is known (see, for example, Patent Document 1). In the slide type switching valve described in Patent Document 1, a pair of pistons are connected by a connecting plate extending in the axial direction and can move forward and backward in the axial direction within the valve housing. At the axial end of the connecting plate, standing plates bent alternately on one side and the other side in the thickness direction intersecting the axial direction are formed, and the pistons are fixed to the connecting plate with the end faces of the standing plates abutting against the plate faces of the pistons. The pistons can move in the axial direction within the valve housing until they abut against the edge of a lid-shaped cap portion that closes the valve housing.

Prior Art Documents

Patent Documents

[0003] <所

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the slide valve described in Patent Document 1, the axial ends of the connecting plate are bent alternately to one side and the other side in the thickness direction to form vertical plates. As a result, it is difficult for the surfaces of the vertical plates to lie on the same plane, and it is conceivable that each vertical plate may be misaligned in the axial direction and in the direction where the axes intersect. In this case, the piston may be tilted with respect to the axis, and when it comes into contact with a stopper such as the edge of the cap, only a part of the piston may come into contact, resulting in so-called uneven contact. If uneven contact occurs, stress will concentrate in that area, which may lead to unstable piston operation and a decrease in the durability of the piston and connecting plate.

[0005] The present invention aims to provide a slide-type switching valve and a refrigeration cycle system capable of improving operational stability and durability. [Means for solving the problem]

[0006] To solve the aforementioned problems and achieve the objective, the present invention provides a slide-type switching valve comprising: a valve housing having a valve chamber inside; a cylindrical piston housed in the valve chamber and moving axially; a connecting member to which the piston is fixed by a fixing member; a valve body held by the connecting member; a valve seat portion having a valve seat surface on which the valve body slides; and a plurality of valve ports provided on the valve seat portion, wherein the connecting member comprises a main body portion that holds the valve body and a piston fixing portion having a fixing surface that protrudes from the main body portion to one side in the height direction intersecting the axial direction and extends continuously in the width direction intersecting the height direction, and the piston is fixed to the connecting member by the fixing member in a state in contact with the fixing surface. Therefore, the position of the main body of the connecting member is offset by a predetermined amount to the other side in the height direction with respect to the axis. It is characterized by the following:

[0007] According to this invention, the piston fixing portion of the connecting member is provided with a fixing surface that extends in the height direction and width direction, that is, extends on the same plane and contacts the piston, so that the piston fixed by the fixing member can be stably supported on the same plane. Furthermore, the configuration of the fixing surface makes it easy to increase the contact area between the connecting member and the piston, and increases the frictional resistance between the connecting member and the piston, so that the piston is less likely to be displaced relative to the connecting member. This prevents tilting of the piston with respect to the axis, and thus prevents the aforementioned uneven contact of the piston, thereby stabilizing the operation of the piston and improving the durability of the piston. In addition, according to this configuration, for example, the piston fixing portion can be formed by bending the end of the connecting member. In this case, the bending direction of the connecting member only needs to be in the height direction, and the piston fixing portion will extend uniformly in the height direction and width direction without being divided. Therefore, it is easy to increase the strength of the piston fixing portion and improve the durability of the piston fixing portion. Thus, it is possible to provide a slide-type switching valve that can improve operational stability and durability. Furthermore, with this configuration, the main body of the connecting member is offset by a predetermined amount to the other side in the height direction relative to the piston axis. This makes it easier to secure space in the valve housing, for example, in the part to the one side in the height direction relative to the connecting member, and this space can be used to increase the thickness of the valve body in the height direction. This improves the strength of the valve body and stabilizes the switching operation of the sliding type switching valve. Also, with this configuration, because the main body of the connecting member is offset to the other side in the height direction, when fixing the piston with a fixing member to a piston fixing part that protrudes to the one side in the height direction relative to the main body, for example, it becomes easier to position the center of gravity of the fixing member near the piston axis. Therefore, it is possible to suppress the generation of a moment that tilts the piston around the piston axis from near the fixing member, and prevent the aforementioned uneven contact of the piston.

[0009] Furthermore, the valve body is formed in a bowl shape that opens toward the valve seat, the main body of the connecting member extends in the axial direction opposite to the valve seat surface, the piston fixing portion is provided protruding toward the valve seat side, which is one side in the height direction, and the portion of the main body that faces the valve seat surface and is located closest to the valve seat is preferably offset by a predetermined amount toward the other side in the height direction with respect to the axis. With such a configuration, the portion of the face that is located closest to the valve seat is offset by a predetermined amount toward the other side in the height direction with respect to the axis, which makes it easier to reliably increase the distance between the valve body and the valve seat. In this case, the opening edge of the bowl-shaped valve body can be made thicker in the height direction by utilizing the space of the offset, which can improve the durability of the valve body and the stability of the valve body when seated.

[0010] Furthermore, in this configuration, it is preferable that at least two of the fixing members are arranged spaced apart from each other, and that through holes for holding the fixing members are formed in the piston fixing portion, with the central axis of the through holes set to the same position as the axis of the piston in the height direction. With this configuration, the piston can be fixed to the connecting member by at least two spaced-apart fixing members. Also, since at least two fixing members are connected to each other by through holes through which they are inserted and piston fixing portions connecting the through holes, for example, if a moment is generated around one fixing member that causes the piston and piston fixing portion to rotate relative to each other, a moment to counteract that moment can be obtained by the other fixing members. As a result, the relative rotation of the piston and connecting member around the axis of one fixing member is suppressed by the other fixing members. In addition, since the central axis of the through holes is set to the same position as the axis of the piston in the height direction, it becomes easier to position the center of gravity of the fixing members held in each through hole even closer to the axis. Therefore, the piston fixed to the connecting member is less likely to tilt, improving the operational stability of the piston and valve body. Furthermore, with this fixed surface configuration, at least two fixed members are aligned on the same plane, making it easier to equally distribute the load, such as sliding resistance between the valve housing and the piston when the piston moves within the valve housing, to each fixed member, thus preventing damage to the fixed members.

[0011] Furthermore, it is preferable that ribs extending toward the valve seat portion are formed on both edges in the width direction of the main body portion. With this configuration, the bending strength can be improved, especially when an axial load is applied to the main body portion, by forming the ribs. In addition, because the ribs extend toward the valve seat portion, it is possible to make the ribs come into contact with the valve body, for example. For this reason, when the valve body tries to lift away from the valve seat portion due to pressure fluctuations in the valve housing, for example, the ribs can function as stoppers to suppress the lifting of the valve body. This improves the operational stability of the piston portion and the valve body.

[0012] Furthermore, it is preferable that the main body is formed in the shape of a rectangular plate extending in the axial direction. With such a configuration, the connecting member can be easily formed by bending, for example, a metal plate member.

[0013] Furthermore, the refrigeration cycle system of the present invention is characterized by comprising a slide-type switching valve as described in any of the above. According to the present invention, a refrigeration cycle system can be configured using a slide-type switching valve that can improve operational stability and durability. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a slide-type switching valve and a refrigeration cycle system that can improve operational stability and durability. [Brief explanation of the drawing]

[0015] [Figure 1] A schematic diagram showing the cooling state of a refrigeration cycle system equipped with a slide-type switching valve according to one embodiment of the present invention. [Figure 2] A cross-sectional view of a sliding type switching valve, cut along the axis of the piston. [Figure 3] A perspective view of the connecting member that constitutes a sliding type switching valve. [Figure 4] Enlarged view of the main part of the sliding type switching valve in Figure 2. [Figure 5] Front view of the piston. [Figure 6] A cross-sectional view of a sliding type switching valve, cut in the thickness direction intersecting the axis. [Modes for carrying out the invention]

[0016] Embodiments of the present invention will be described below with reference to Figures 1 to 6. In the following description, the direction in which the axis X of the piston 50, which will be described later, extends will be referred to as the "axis X direction," with one side of the axis X direction being referred to as "side X1" and the other side as "other side X2." The direction perpendicular (intersecting) the axis X direction and the depth direction of the valve body 70, which will be described later, will be referred to as the "height direction Z," with one side of the height direction Z being referred to as "lower side Z2" and the other side as "upper side Z1." The direction perpendicular to the axis X direction and the height direction Z will be referred to as the "width direction Y," with one side of the width direction Y being referred to as "left side Y1" and the other side as "right side Y2." These definitions of directions are for the convenience of explanation only and do not necessarily coincide with the directions in the actual usage conditions of the present invention, nor do they limit the directions.

[0017] Figure 1 shows the cooling state of a refrigeration cycle system 100 according to an embodiment of the present invention. The refrigeration cycle system 100 includes a pilot valve 1, a slide-type switching valve 2, an indoor heat exchanger 3, a throttling device 4, an outdoor heat exchanger 5, and a compressor 6. The pilot valve 1 is a valve device that allows a driving fluid to flow between the pilot valve 1 and the slide-type switching valve 2 in order to move the valve body 70 of the slide-type switching valve 2. As shown in Figure 1, the pilot valve 1 includes a valve body 10. The valve body 10 is formed into a cylindrical shape by press-forming a metal material such as stainless steel. A D-tube 11, a first operating tube 12, an S-tube 13, and a second operating tube 14, which communicate with the inside of the valve body 10, are fixed to the side wall of the valve body 10 by brazing or the like. The D-tube 11 is a high-pressure pipe through which a high-pressure driving fluid flows, and is connected to and communicates with the D-joint pipe 22a of the slide-type switching valve 2, which will be described later.

[0018] On one side, the first actuating capillary tube 12, the S capillary tube 13, and the second actuating capillary tube 14 are pipes through which high-pressure driving fluid and low-pressure driving fluid flow. The first actuating capillary tube 12 communicates with a first actuating chamber 29b, which will be described later, of the slide-type switching valve 2. The S capillary tube 13 communicates with an S joint pipe 25a, which will be described later, of the slide-type switching valve 2. The second actuating capillary tube 14 communicates with a second actuating chamber 29c, which will be described later, of the slide-type switching valve 2. An electromagnetic driving unit 15 for moving a plunger and a valve body (not shown) disposed inside the valve body 10 is attached to the end of the other side X2 of the valve body 10. The electromagnetic driving unit 15 includes an electromagnetic coil 16. When a voltage is applied to the electromagnetic driving unit 15, the electromagnetic coil 16 is excited, and the valve body in the valve body 10 is moved by the magnetic force generated between the electromagnetic coil 16 and the plunger. Then, the communication state of the D capillary tube 11, the first actuating capillary tube 12, the S capillary tube 13, and the second actuating capillary tube 14 is switched by the moved valve body.

[0019] The slide-type switching valve 2 is a valve device that switches the refrigerant flow path by switching the communication state of four pipes. As shown in FIG. 2, the slide-type switching valve 2 includes a valve housing 20 formed in a cylindrical shape using a metal material such as stainless steel. The valve housing 20 includes a cylindrical portion 21 formed in a cylindrical shape extending in the axial direction X. A D port 22 penetrating in the height direction Z is formed in the side wall of the cylindrical portion 21 by burring or the like, and a D joint pipe 22a as a high-pressure pipe communicating with the D port 22 is fixed by brazing or the like. A plate-like valve seat portion 23 extending in the axial direction X is provided on the inner surface of the side wall of the cylindrical portion 21 so as to face the D port 22. The valve seat portion 23 is formed in a plate shape with a valve seat surface 23a on which the valve body 70 can slide, and an E port 24, an S port 25, and a C port 26 penetrating in the height direction Z are formed in this order from the one side X1 to the other side X2 on the valve seat surface 23a. That is, a plurality of valve ports are formed in the valve seat portion 23.

[0020] On the side wall of the cylindrical portion 21, an E joint pipe 24a communicating with the E port 24, an S joint pipe 25a communicating with the S port 25, and a C joint pipe 26a communicating with the C port 26 are respectively fixed by brazing or the like. The E joint pipe 24a, the S joint pipe 25a, and the C joint pipe 26a are pipes through which the refrigerant flows, similar to the D joint pipe 22a, and function as high-pressure pipes or low-pressure pipes. Cover members 27 are installed at the openings at both ends of the cylindrical portion 21 in the axial direction X. The cover member 27 is formed in a substantially bowl shape that opens inward in the axial direction X, and is fixed by welding or the like in a state of being fitted into the mounting step portions 28 formed with an enlarged diameter at both ends of the cylindrical portion 21 in the axial direction X. Thereby, the space between the cylindrical portion 21 and the cover member 27 is sealed, and a valve chamber 29 is formed in the valve housing 20. The valve chamber 29 is partitioned into three spaces, a first working chamber 29b, a high-pressure chamber 29a, and a second working chamber 29c, in order from one side X1 to the other side X2 by a piston 50 described later.

[0021] One end of the above-described first working capillary 12 is inserted through the wall surface of the cover member 27 disposed on one side X1 of the cover member 27, whereby the inside of the valve body 10 of the pilot valve 1 and the first working chamber 29b communicate with each other. On the other hand, one end of the above-described second working capillary 14 is inserted through the wall surface of the cover member 27 disposed on the other side X2 of the cover member 27, whereby the inside of the valve body 10 of the pilot valve and the second working chamber 29c communicate with each other. In this embodiment, by inserting one end of the first working capillary 12 through the cover member 27, one end of the first working capillary 12 is made to communicate with the first working chamber 29b. However, the present invention is not limited to this, and one end of the first working capillary 12 may be made to communicate with the first working chamber 29b by inserting it through the wall surface of the cylindrical portion 21 of the valve housing 20. Similarly, one end of the second working capillary 14 may be made to communicate with the second working chamber 29c by inserting it through the wall surface of the cylindrical portion 21 of the valve housing 20.

[0022] The inner diameter of the lid member 27 is set to be smaller than the inner diameter of the cylindrical portion 21, so that the open end surface 27a of the lid member 27 can abut against the piston portion 30, which will be described later, in the axial X direction. With this configuration, the open end surface 27a of the lid member 27 functions as a stopper that restricts the displacement of the piston portion 30 housed in the valve chamber 29 in the axial X direction. Note that this function as a stopper is merely an example; for example, the central part of the inner surface of the lid member 27 may be made to protrude inward in the axial X direction, so that the protruding end can abut against the piston portion 30, and this protruding end may be used as a stopper. The piston portion 30 is the part that divides the inside of the cylindrical portion 21 into three spaces: the high-pressure chamber 29a, the first working chamber 29b, and the second working chamber 29c, and is equipped with a connecting member 40 that extends in the axial X direction and holds the valve body 70, which will be described later.

[0023] The connecting member 40 is formed by bending a metal plate such as stainless steel and has a rectangular plate-shaped main body portion 41 that extends in the axial direction X. The main body portion 41 is positioned offset by a predetermined amount upward Z1 with respect to the axial direction X, and its lower surface Z2 extends opposite the valve seat surface 23a in the height direction Z, and this lower surface Z2 constitutes the opposing surface 41a. An oval-shaped valve body holding portion 42 that penetrates in the height direction Z is formed in the center of the main body portion 41, and the valve body 70 is positioned inside the valve body holding portion 42 so that it cannot come out in the axial direction X and the height direction Z. In other words, the valve body 70 is held in the main body portion 41 of the connecting member 40 via the valve body holding portion 42. The valve body 70 comprises a bowl-shaped portion 71 having a concave portion 72 that opens toward the valve seat surface 23a, and a flange portion 73 that protrudes outward from the opening edge of the concave portion 72, and is formed in a bowl shape that opens toward the valve seat portion 23.

[0024] The valve body 70 is normally pressed against the valve seat surface 23a by the differential pressure between the high-pressure chamber 29a and the E-connector pipe 24a, S-connector pipe 25a, or C-connector pipe 26a. As a result, the valve body 70, while held by the connecting member 40, can move forward and backward in the axial X direction while the sealing surface 74, formed by the lower end face Z2 of the flange portion 73, slides against the valve seat surface 23a. The opening of the concave portion 72 of the valve body 70 is formed to cover two adjacent openings among the E-port 24, S-port 25, and C-port 26. As a result, the movement of the valve body 70 forward and backward in the axial X direction switches the communication state of the E-port 24 (E-connector pipe 24a), S-port 25 (S-connector pipe 25a), C-port 26 (C-connector pipe 26a), and D-port 22 (D-connector pipe 22a). Specifically, the concave portion 72 connects the E port 24 (E fitting pipe 24a) and the S port 25 (S fitting pipe 25a) internally at position X1 on one side as shown in Figure 1, and connects the D port 22 (D fitting pipe 22a) and the C port 26 (C fitting pipe 26a) externally.

[0025] In this state, the high-pressure refrigerant that flows into the valve chamber 29 through the D joint pipe 22a flows to the valve seat portion 23 side through the pressure equalization hole 43 (described later) and flows to the C joint pipe 26a which is not covered by the concave portion 72. On the other hand, the low-pressure refrigerant that flows into the concave portion 72 through the S joint pipe 25a flows to the E joint pipe 24a. In contrast, when the valve body 70 moves from one side X1 position to the other side X2 position shown in Figure 2, the concave portion 72 connects the C port 26 (C joint pipe 26a) and the S port 25 (S joint pipe 25a) internally, and connects the D port 22 (D joint pipe 22a) and the E port 24 (E joint pipe 24a) externally. In this state, the high-pressure refrigerant that flows into the valve chamber 29 through the D joint pipe 22a flows through the pressure equalization hole 43 towards the valve seat 23 and into the E joint pipe 24a which is not covered by the concave portion 72. On the other hand, the low-pressure refrigerant that flows into the concave portion 72 through the S joint pipe 25a flows into the C joint pipe 26a.

[0026] As shown in Figure 2, in the connecting member 40, circular pressure equalization holes 43 are formed on one side X1 and the other side X2 of the valve body holding portion 42 that holds the valve body 70, respectively, penetrating in the height direction Z. The pressure equalization holes 43 are holes that connect the upper Z1 portion and the lower Z2 portion of the main body portion 41 within the valve housing 20, and the formation of these pressure equalization holes 43 allows the D joint pipe 22a, the inside of the valve housing 20, the E joint pipe 24a, the S joint pipe 25a, and the C joint pipe 26a to communicate. As shown in Figure 3, both edges in the width direction Y of the main body portion 41 are bent downwards to Z2 and protrude downwards to Z2. Due to the formation of these protruding portions, the height direction Z dimension of both edges in the width direction Y of the main body portion 41 is larger than that of other parts, and these protruding portions constitute ribs 44. In other words, ribs 44 are provided on both Y-edges in the width direction of the opposing surface 41a of the main body portion 41, and the ribs 44 are formed to extend continuously in the axial X direction.

[0027] The formation of the rib 44 improves the bending strength, especially when a load is applied to the main body 41 in the axial X direction. The lower surface 44a of the rib 44, like the lower Z2 surface of the main body 41 described above, faces the valve seat surface 23a in the height direction Z and constitutes the opposing surface 41a. The opposing surface 41a formed by the lower surface 44a of the rib 44 is located closer to the valve seat surface 23a (valve seat portion 23 side) than the opposing surface 41a formed by the lower Z2 surface of the main body 41. In other words, the opposing surface 41a formed by the lower surface 44a of the rib 44 is the part of the opposing surface 41a that is closest to the valve seat surface 23a (valve seat portion 23 side). As shown in Figure 6, the opposing surface 41a formed by the lower surface 44a of the rib 44 can contact the upper end surface 75 of the flange portion 73 of the valve body 70, and functions as a stopper when the valve body 70, which is normally pressed against the valve seat surface 23a as described above, tries to float up to the upper Z1 unintentionally due to pressure fluctuations in the high-pressure chamber 29a or pressure fluctuations in the E joint pipe 24a, S joint pipe 25a, or C joint pipe 26a.

[0028] As shown in Figure 3, both ends of the main body 41 in the axial direction X are bent downward Z2 (one side in the height direction Z, towards the valve seat 23), and these bent portions constitute a pair of piston fixing parts 45 to which the piston 50 is fixed by fixing screws 61 (fixing members) of the fixing means 60, which will be described later. That is, the piston fixing parts 45 are provided on one side X1 and the other side X2 of the main body 41, and protrude toward the valve seat 23. Note that the piston fixing parts 45 and the piston 50, which will be fixed to the piston fixing parts 45 by the fixing screws 61 (fixing members) shown in Figure 4, have the same structure on one side X1 and the other side X2, so in the following description, a detailed explanation of the structure of the one side X1 portion will be omitted, and the structure of the other side X2 portion will be described in detail. As shown in Figure 3, the piston fixing parts 45 have the same wall thickness as the main body 41 and extend in the width direction Y and the height direction Z, respectively. The surface of the piston fixing portion 45 facing outward in the axial direction X constitutes a fixing surface 46 that contacts the piston 50. The fixing surface 46 is continuous with the main body portion 41, protrudes downward Z2, and extends continuously in the width direction Y. The piston fixing portion 45 is provided with multiple (at least two) through holes 47 that penetrate from the fixing surface 46 in the axial direction X (plate thickness direction).

[0029] Specifically, in this embodiment, two through holes 47 are formed, and their respective central axes x1, parallel to the axis X, are spaced apart in the width direction Y so that they are at the same position as the axis X in the height direction Z. Female threads 62 are formed on the inner circumferential surface of the through holes 47, which are screwed into the male threads 65 of the fixing screws 61 described later. Due to the arrangement of these through holes 47 and female threads 62, at least two fixing screws 61, which are an example of a fixing member described later, are arranged spaced apart from each other in the width direction, and the fixing screws 61 screwed into the female threads 62 are held in place by the through holes 47. As shown in Figure 4, a cylindrical piston 50 is fixed to the fixing surface 46 of the piston fixing part 45. The piston 50 is equipped with a packing 51. The packing 51 is the part that divides the valve chamber 29 into a high-pressure chamber 29a, a first working chamber 29b, and a second working chamber 29c, and is formed in a bottomed cylindrical shape by a disc-shaped bottom 52 and side walls 53 that rise inward in the axial X direction from the outer peripheral edge of the bottom 52.

[0030] The outer surface of the side wall 53 of the packing 51 is slidable in close contact with the inner circumferential surface of the valve housing 20. A first reinforcing plate 54 is positioned on one side X1 of the packing 51. The first reinforcing plate 54 is formed in the shape of a disc with a central axis coaxial with the bottom 52 of the packing 51, and is approximately the same size as the bottom 52 of the packing 51. On the other side X2 of the packing 51, a second reinforcing plate 55 is positioned. The second reinforcing plate 55 is formed in the shape of a disc with a larger diameter than the bottom 52 of the packing 51, and has a central axis coaxial with the disc. The piston 50 formed in this way has at least two through holes 56a that penetrate in the direction of the axis X. Specifically, two through holes 56a are formed, one of which is positioned on the upper side Z1 of the axis X, and the other of which is positioned on the lower side Z2 of the axis X. As shown in Figure 5, the two through holes 56a are formed at positions where their respective central axes x2 are separated by the same distance in the height direction Z with respect to the axis X. Furthermore, the central axes x2 of the two through holes 56a are located at the same position as the axis X in the width direction Y. Rivets 56 extending in the direction of the axis X are inserted through the through holes 56a, and these rivets 56 fix the packing 51, the first reinforcing plate 54, and the second reinforcing plate 55 together in a tightly packed state in the direction of the axis X. Note that the central axes x3 of the two rivets 56 shown in Figure 4 are coaxial with the central axis x2 of the through holes 56a, and the arrangement of the central axes x2 of the through holes 56a is as described above. Therefore, the two rivets 56 are separated by the same distance in the height direction Z with respect to the axis X, and are located at the same position as the axis X in the width direction Y. Consequently, the center of gravity of the rivets 56 is located near the axis X.

[0031] In the piston 50 fixed by rivets 56, the other end face X2 of the first reinforcing plate 54 is in close contact with the end face X1 of one side of the bottom 52 of the packing 51, and the end face X1 of one side of the second reinforcing plate 55 is in close contact with the end face X2 of the other side of the bottom 52 of the packing 51, so that the packing 51 is sandwiched in the axial direction X by the first reinforcing plate 54 and the second reinforcing plate 55. The piston 50 thus formed is fixed to the piston fixing part 45 by fixing means 60, as shown in Figure 4. The fixing means 60 consists of, for example, a fixing screw 61 (fixing member) such as a bolt and a female screw 62 formed in the through hole 47 described above. The fixing screw 61 is prepared in accordance with the number of through holes 47 described above (two in this embodiment) and comprises a head 63, a shaft portion 64 extending from the head 63 to one side X1, and a male screw 65 formed on the outer circumferential surface of the shaft portion 64. One side X1 of the head 63 is in contact with the other end face X2 of the second reinforcing plate 55 of the piston 50.

[0032] The shaft portion 64 is inserted through a second through hole (not shown) that is the same diameter and coaxial as the through hole 47 of the piston fixing portion 45 described above, and further extends in the direction of the axis X by being inserted through the through hole 47. The male screw 65 is screwed into the female screw 62 within the through hole 47. As described above, the central axis x1 of the two through holes 47 through which the shaft portion 64 is inserted is parallel to the axis X and is located at the same position as the axis X in the height direction Z. Therefore, as shown in Figure 5, the central axis x4 of the fixing screw 61 is also located at approximately the same position as the axis X in the height direction Z, and as a result, the center of gravity of the fixing screw 61 is located near the axis X.

[0033] In this embodiment, a fixing screw 61 such as a bolt is given as an example of a fixing member, but the fixing member is not limited to this, and for example, a set screw without a head 63 may be used as a fixing member. Alternatively, the fixing member may be the rivet 56 described above, or a cylindrical or cylindrical projection that fits into the through hole 47. In this case, the female thread 62 in the through hole 47 of the piston fixing part 45 can be omitted, and the piston 50 can be fixed to the piston fixing part 45 by installing the rivet 56 described above in the through hole 47. Alternatively, the piston 50 can be fixed to the piston fixing part 45 by press-fitting the projection into the through hole 47 or by spot welding.

[0034] Next, the assembly of the piston portion 30 in the sliding type switching valve 2 will be described. First, a metal plate is bent to form a connecting member 40 having a main body portion 41, ribs 44, and a piston fixing portion 45. Then, a through hole 47 and an internal thread 62 are formed in the piston fixing portion 45. In this embodiment, there are two through holes 47, and the two through holes 47 are formed so that their respective central axes x1, which are parallel to the axis X as described above, are at the same position as the axis X in the height direction Z, and are spaced apart in the width direction Y. Next, the piston 50, with a packing 51, a first reinforcing plate 54, and a second reinforcing plate 55 fixed to it with rivets 56, is attached to the piston fixing portion 45 of the connecting member 40.

[0035] In this case, the piston 50 is positioned so that the second through hole (not shown) of the piston 50 is coaxial with the through hole 47 and female thread 62 of the piston fixing part 45, and with one side X1 of the first reinforcing plate 54 in contact with the fixing surface 46 of the piston fixing part 45, the fixing screw 61 is tightened into the female thread 62. As a result, the piston 50 is fixed to the connecting member 40 by the fixing screw 61 while in contact with the fixing surface 46, and the assembly of the piston part 30 is completed. In this embodiment, two through holes 47 and female threads 62 are formed and two corresponding fixing screws 61 are provided, but this is not limited to this, and three or more through holes 47, female threads 62, and fixing screws 61 may be provided. Also, in this embodiment, two through holes 56a and rivets 56 are provided, but this is not limited to this, and three or more through holes 56a and rivets 56 may be provided. In this manner, if three or more through holes 47, female threads 62, fixing screws 61, insertion holes 56a, and rivets 56 are provided, it is advisable to adjust their arrangement so that, similar to this embodiment, the center of gravity of the fixing screws 61 and the center of gravity of the rivets 56 are located near the axis X.

[0036] The assembled piston portion 30 is then housed in the valve housing 20. The position of the connecting member 40 within the valve housing 20 can be set as appropriate. However, as shown in Figure 6, it is preferable that the opposing surface 41a formed by the lower surface 44a of the rib 44 of the main body portion 41 is offset by a predetermined amount to the upper side Z1 (to the other side in the height direction Z) with respect to the axis X. Specifically, for example, as shown in Figure 6, it is preferable that the opposing surface 41a formed by the lower surface 44a of the rib 44 of the main body portion 41 extends on a virtual surface Y2 which is an offset of a virtual surface Y that extends in the width direction Y perpendicular to the axis X to the upper side Z1. In this case, the height dimension α of the flange portion 73 (opening edge portion) of the valve body 70 can be increased by utilizing the offset space β. That is, the flange portion 73 of the valve body 70 can be made thicker in the height direction Z, improving the durability of the valve body 70 and the stability of the valve body 70 when seated.

[0037] As shown in Figure 2, the assembled piston 30 is installed inside the valve housing 20 and moves back and forth in the axial direction X within the valve housing 20. However, in this process, the area where the fixing means 60 is located and its surroundings are prone to a load due to the sliding resistance between the packing 51 and the inner circumferential surface of the valve housing 20. This causes relative displacement between the piston 50 and the connecting member 40, potentially causing the piston 50 to tilt with respect to the axial direction X. If the tilted piston 50 were to come into contact with the open end surface 27a of the cover member 27, stress would concentrate at predetermined locations on the piston 50 and the connecting member 40, potentially reducing the operational stability and durability of the sliding type switching valve 2. However, in this configuration, since the fixing surface 46 of the piston fixing part 45 extends in the height direction and the width direction Y, i.e., extends on the same plane, the fixed piston 50 is stably supported on the same plane, making it difficult for the piston 50 to tilt with respect to the axial direction X.

[0038] Furthermore, since the fixing surface 46 extends on the same plane, the contact area between the fixing surface 46 and the first reinforcing plate 54 can be easily increased, and the frictional resistance between the piston fixing part 45 and the piston 50 can be increased, making it difficult for the piston 50 to be displaced relative to the piston fixing part 45. In addition, with this configuration, the bending direction of the piston fixing part 45 only needs to be in one direction, so the piston fixing part 45 extends uniformly in the height direction Z and the width direction Y without being divided. Therefore, the strength of the piston fixing part 45 can be easily increased, and the durability of the piston fixing part can be improved. Also, in the piston fixing part 45, at least two through holes 47 are provided spaced apart from each other, so one fixing screw 61 that is held in these through holes 47 and screwed into the female thread 62 in the through hole 47 and the other fixing screw 61 are connected to each other by the female thread 62 into which they are screwed and the piston fixing part 45 that connects them.

[0039] Therefore, if the aforementioned sliding resistance load generates a moment that causes the piston 50 and piston fixing part 45 to rotate relative to one fixing screw 61, for example, another fixing screw 61 can provide a moment to counteract that moment. Thus, the relative rotation of the piston 50 and connecting member 40 around the axis of the first fixing screw 61 is suppressed by the other fixing screws 61. This is also true when there are three or more through holes 47, female threads 62, and fixing screws 61.

[0040] Furthermore, since the position of the central axis x1 of the through hole 47 is set to the same position as the axis X of the piston 50 in the height direction Z, the center of gravity of each fixing screw 61 (fixing member) is located near the axis X, as described above. As a result, the piston 50 fixed to the connecting member 40 becomes less likely to tilt, and the operational stability of the piston 50 and valve body 70 is improved. In addition, according to this embodiment, as described above, the center of gravity of the rivet 56 is also located near the axis X, so the tilting of the piston 50 is suppressed even further. Furthermore, with the configuration of the fixing surface 46, at least two fixing screws 61 (fixing means 60) and at least two rivets 56 are aligned on the same plane, so the load such as sliding resistance between the valve housing 20 and the piston 50 when the piston 50 moves within the valve housing 20 is easily distributed equally to the fixing screws 61 and rivets 56, preventing damage to the fixing screws 61 and rivets 56.

[0041] Next, the operation of the refrigeration cycle system 100 will be described. In the refrigeration cycle system 100, the pilot valve 1 changes the flow state of the drive fluid, which moves the valve body 70 of the slide-type switching valve 2, thereby switching between the cooling state shown in Figure 1 and the heating state (not shown). In the cooling state, high-pressure drive fluid flows through the second operating tube 14 of the pilot valve 1 into the second operating chamber 29c of the slide-type switching valve 2 shown in Figure 1. Low-pressure drive fluid also flows through the first operating tube 12 of the pilot valve 1 into the first operating chamber 29b of the slide-type switching valve 2 shown in Figure 1. This creates a pressure difference between the first operating chamber 29b and the second operating chamber 29c, causing the piston portion 30 of the slide-type switching valve 2 to move to one side X1, and the valve body 70 to move to the one side X1 position shown in Figure 1. In this state, the high-pressure refrigerant compressed by the compressor 6 flows into the high-pressure chamber 29a from the D joint pipe 22a, passes through the equalization hole 43, and flows into the outdoor heat exchanger 5 from the C joint pipe 26a. In other words, during cooling operation, the refrigerant discharged from the compressor 6 circulates through the C joint pipe 26a, the outdoor heat exchanger 5, the throttling device 4, the indoor heat exchanger 3, and the E joint pipe 24a, with the outdoor heat exchanger 5 functioning as a condenser and the indoor heat exchanger 3 functioning as an evaporator.

[0042] On the other hand, in the heating state, high-pressure drive fluid flows through the first operating tube 12 of the pilot valve 1 into the first operating chamber 29b of the slide-type switching valve 2 shown in Figure 2. Also, low-pressure drive fluid flows through the second operating tube 14 of the pilot valve 1 into the second operating chamber 29c of the slide-type switching valve 2 shown in Figure 2. As a result, a pressure difference is created between the first operating chamber 29b and the second operating chamber 29c, causing the piston portion 30 of the slide-type switching valve 2 to move to the other side X2, and the valve body 70 to move to the other side X2 position shown in Figure 2. In this state, the high-pressure refrigerant compressed by the compressor 6 flows into the high-pressure chamber 29a from the D joint pipe 22a and flows into the indoor heat exchanger 3 from the E joint pipe 24a through the pressure equalization hole 43. In other words, during heating operation, the refrigerant discharged from the compressor 6 circulates through the E fitting pipe 24a, indoor heat exchanger 3, throttling device 4, outdoor heat exchanger 5, and C fitting pipe 26a, with the indoor heat exchanger 3 functioning as a condenser and the outdoor heat exchanger 5 functioning as an evaporator.

[0043] In the sliding type switching valve 2, repeated switching between cooling and heating states makes it easy for loads in the axial X direction to be applied to the connecting member 40. Therefore, if the main body 41 is deformed, the operation of the piston 30 and valve body 70 may become unstable. However, in this configuration, by forming ribs 44 on the main body 41 of the connecting member 40, the bending strength when loads in the axial X direction are applied to the main body 41 is improved. This also improves the operational stability of the piston 30 and valve body 70. Furthermore, in the sliding type switching valve 2, as described above, the valve body 70, which is normally pressed against the valve seat surface 23a, may unintentionally try to float upward Z1 due to pressure fluctuations in the high-pressure chamber 29a or pressure fluctuations in the E joint pipe 24a, S joint pipe 25a, or C joint pipe 26a.

[0044] However, in this configuration, the valve body 70 can be prevented from lifting up by bringing the upper end surface 75 of the flange portion 73 of the valve body 70 into contact with the opposing surface 41a formed by the lower surface 44a of the rib 44. Furthermore, in this configuration, since the opposing surface 41a formed by the lower surface 44a of the rib 44 is offset by a predetermined amount upward Z1 with respect to the axis X, the height dimension α of the flange portion 73 of the valve body 70 can be increased by utilizing the space β of the offset. In other words, the flange portion 73 of the valve body 70 can be made thicker in the height direction Z, improving the durability of the valve body 70 and the stability of the valve body 70 when seated.

[0045] As described above, according to the embodiment, the piston fixing portion 45 of the connecting member 40 is provided with a fixing surface 46 that extends in the height direction Z and the width direction Y, that is, extends on the same plane and contacts the piston 50. Therefore, the piston 50 fixed by the fixing screw 61 (fixing member) can be stably supported on the same plane. Furthermore, the configuration of the fixing surface 46 makes it easier to increase the contact area between the connecting member 40 and the piston 50, and increases the frictional resistance between the connecting member 40 and the piston 50, making it difficult to displace the piston 50 relative to the connecting member 40. This prevents the piston 50 from tilting with respect to the axis X, and thus prevents the aforementioned uneven contact of the piston 50, thereby stabilizing the operation of the piston 50 and improving the durability of the piston 50. In addition, according to this configuration, the bending direction of the connecting member 40 only needs to be in the height direction Z, and the piston fixing portion 45 extends uniformly in the height direction Z and the width direction Y without being divided. Therefore, it is easier to increase the strength of the piston fixing portion 45 and improve the durability of the piston fixing portion. Therefore, it is possible to provide a slide-type switching valve that can improve operational stability and durability.

[0046] Furthermore, because the main body portion 41 of the connecting member 40 is offset by a predetermined amount upward Z1 (to the other side in the height direction) with respect to the axis X of the piston 50, it is easier to secure space in the valve housing 20 below the connecting member 40 Z2 (to one side in the height direction), for example, and by utilizing this space, the wall thickness of the valve body 70 can be increased in the height direction Z. This improves the strength of the valve body 70 and stabilizes the switching operation of the sliding type switching valve 2. In addition, with this configuration, because the main body portion 41 of the connecting member 40 is offset upward Z1, for example, when fixing the piston 50 with a fixing screw 61 (fixing member) to the piston fixing portion 45 that protrudes downward Z2 from the main body portion 41, it is easier to position the center of gravity of the fixing screw 61 close to the axis X of the piston 50. Therefore, it is possible to suppress the generation of a moment that tilts the piston 50 around the axis X of the piston 50 from the vicinity of the fixing screw 61, and the aforementioned uneven contact of the piston 50 can be prevented.

[0047] Furthermore, according to this embodiment, the portion of the opposing surface 41a located furthest towards the valve seat surface 23a (valve seat portion 23 side) relative to the axis X is offset by a predetermined amount so as to be further upward Z1 (to the other side in the height direction), thereby making it easier to reliably increase the distance between the valve body 70 and the valve seat portion 23. In this case, the space β of the offset can be used to make the flange portion 73 (opening edge portion) of the bowl-shaped valve body 70 thicker in the height direction Z, thereby improving the durability of the valve body 70 and the stability of the valve body 70 when seated.

[0048] Furthermore, according to this embodiment, the piston 50 can be fixed to the connecting member 40 by at least two spaced-apart fixing screws 61. In addition, since the at least two fixing screws 61 are connected to each other by through holes 47 through which they are inserted and piston fixing parts 45 that connect the through holes 47, for example, if a moment is generated around one fixing screw 61 that causes the piston 50 and piston fixing part 45 to rotate relative to each other, a moment to counteract that moment can be obtained by the other fixing screws 61. As a result, the relative rotation of the piston 50 and the connecting member 40 around the axis of one fixing screw 61 is suppressed by the other fixing screws 61. Also, since the position of the central axis x1 of the through hole 47 is set to be the same as the axis X of the piston 50 in the height direction Z, it becomes easier to position the center of gravity of the fixing screws 61 held in each through hole 47 even closer to the axis X. Furthermore, according to this embodiment, the center of gravity of the rivet 56 can also be positioned closer to the axis X. Therefore, the fixed piston 50 is less likely to tilt, improving the operational stability of the piston 50 and the valve body 70. Furthermore, with the configuration of the fixing surface 46, at least two fixing screws 61 and at least two rivets 56 are aligned on the same plane, making it easier to equally distribute the load, such as sliding resistance between the valve housing 20 and the piston 50 when the piston 50 moves within the valve housing 20, to each fixing screw 61 and each rivet 56, thereby preventing damage to the fixing screws 61, etc.

[0049] Furthermore, according to this embodiment, the formation of the rib 44 improves the bending strength, especially when a load is applied to the main body 41 in the axial X direction. Also, since the rib 44 extends toward the valve seat portion 23, it is possible to make the rib 44 come into contact with the valve body 70, for example. Therefore, when the valve body 70 tries to lift away from the valve seat portion 23 due to pressure fluctuations within the valve housing 20, for example, the rib 44 can function as a stopper to suppress the lifting of the valve body 70. This improves the operational stability of the piston portion 30 and the valve body 70.

[0050] Furthermore, according to this embodiment, the connecting member 40 can be easily formed by bending a metal plate member or the like.

[0051] Furthermore, according to this embodiment, the refrigeration cycle system 100 can be configured using a slide-type switching valve 2 that can improve operational stability and durability.

[0052] Furthermore, the embodiments described above merely represent typical forms of the present invention, and the present invention is not limited thereto. That is, it can be implemented with various modifications without departing from the core principles of the present invention. As long as such modifications still possess the configuration of the slide-type switching valve 2 of the present invention, they are of course included within the scope of the present invention. For example, in this embodiment, the connecting member 40 was formed by bending a metal plate, but it is not limited to this. For example, the connecting member 40 may be formed by cutting a rectangular block-shaped metal material extending in the axial direction X, or a rectangular block-shaped metal material may be drawn to form a so-called bathtub shape with a recess inside, and this may be used as the connecting member 40.

[0053] This allows the ribs 44 and piston fixing portion 45 of the connecting member 40 to protrude downward Z2 without bending. In addition to forming the ribs 44 of the connecting member 40 by bending both edges in the width direction Y of the main body portion 41 of the connecting member 40 downward Z2 and making them protrude, as described above, they can also be formed by cutting or drawing. However, the method is not limited to these, and a projection separate from the main body portion 41 may be attached to the edge of the main body portion 41 to increase the height direction Z of the edge, thereby forming the ribs 44. Similarly, a plate member separate from the connecting member 40 may be attached to the main body portion 41 to provide a fixing surface 46 that protrudes from the main body portion 41 in the height direction Z, thereby forming the piston fixing portion 45. [Explanation of Symbols]

[0054] X axis Y width direction Z (height direction) 2. Slide-type switching valve 20 valve housing 23 Valve seat 23a Valve seat surface 24 E-ports (multiple valve ports) 25 S-ports (multiple valve ports) 26 C ports (multiple valve ports) 29 Valve chambers 40 Connecting member 41 Main body 45 Piston fixing part 46 Fixed surface 50 pistons 61 Fixing screws (fixing components) 70 Valve body

Claims

1. A sliding type switching valve comprising: a valve housing having a valve chamber inside; a cylindrical piston housed in the valve chamber and moving axially; a connecting member to which the piston is fixed by a fixing member; a valve body held by the connecting member; a valve seat portion having a valve seat surface on which the valve body slides; and a plurality of valve ports provided on the valve seat portion, The connecting member comprises a main body portion that holds the valve body, and a piston fixing portion having a fixing surface that protrudes from the main body portion to one side in the height direction intersecting the axial direction and extends continuously in the width direction intersecting the height direction. The piston is fixed to the connecting member by the fixing member while in contact with the fixed surface. A sliding type switching valve characterized in that the position of the main body portion of the connecting member is offset by a predetermined amount to the other side in the height direction with respect to the axis.

2. The valve body is formed in a bowl shape that opens toward the valve seat portion, The main body of the connecting member extends in the axial direction opposite to the valve seat surface, The piston fixing portion is provided so as to protrude toward the valve seat portion on one side in the height direction, The sliding switching valve according to claim 1, characterized in that the portion of the main body facing the valve seat surface that is located closest to the valve seat is offset by a predetermined amount to the other side in the height direction with respect to the axis.

3. The aforementioned fixing members are arranged in pairs, spaced apart from each other. Each of the piston fixing portions has a through hole formed therein for holding the fixing member. The sliding switching valve according to claim 2, characterized in that the position of the central axis of the through hole is set to the same position as the axis of the piston in the height direction.

4. The sliding switching valve according to claim 2, characterized in that ribs extending toward the valve seat portion are formed on both edges in the width direction of the main body portion.

5. The sliding switching valve according to claim 3, characterized in that the main body is formed in the shape of a rectangular plate extending in the axial direction.

6. A refrigeration cycle system characterized by comprising a slide-type switching valve as described in any one of claims 1 to 5.

Images