Slide-type switching valve

Abstract

To provide a slide type switching valve which improves fixing strength of a valve seat member fixed to a valve body and inhibits deformation and peeling of the valve seat member to improve valve leakage performance.SOLUTION: A slide type switching valve 1 includes a valve body 10, a valve seat member 21, a valve element 30, and a drive part 40. The valve seat member 21 has: a slide contact surface 22 with which the valve element 30 slidably contacts; and a close contact surface a including a curved surface 23 which curves protruding to the opposite side of the slide contact surface 22. A surface area of the close contact surface a is larger than a surface area of the slide contact surface 22. The close contact surface a of the valve seat member 21 is provided contacting closely with an inner peripheral surface of the valve body 10.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a slide-type switching valve. [Background technology]

[0002] A known switching valve for switching the flow path of a refrigerant in a refrigeration cycle or the like is a slide-type switching valve that includes a cylindrical valve body, a valve element slidably provided within the valve body, a valve seat member provided on the valve body, and a drive unit that drives the valve element to slide in the axial direction (see, for example, Patent Document 1). The valve body is a resin-molded part, and the valve seat member is made of a thin metal plate and is fixed to the valve body by adhesive or insert molding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-150818 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional slide-type switching valves, the resin valve body is easily deformed due to internal and external pressure fluctuations, etc. Therefore, the valve seat member made of a thin metal plate deforms as the valve body deforms, which can lead to valve leakage due to a decrease in the sealing performance between the valve disc and the valve seat member. On the other hand, when a valve seat member made of a thick metal plate is used in a slide-type switching valve, the valve body is easily deformed while the valve seat member is less likely to deform, which can lead to the valve seat member peeling off from the valve body as the valve body deforms.

[0005] An object of the present invention is to provide a slide-type switching valve that improves valve leakage performance by increasing the fixing strength of the valve seat member to the valve body and suppressing deformation and peeling of the valve seat member. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the object, the slide-type switching valve of the present invention is a slide-type switching valve comprising: a hollow cylindrical valve body; a valve seat portion provided in the valve body; a valve element provided inside the valve body so as to be slidable in an axial direction; and a drive portion that drives the valve element to slide, wherein the valve seat portion has a metal valve seat member that is integrated with a resin that forms the valve body by insert molding, and the valve seat member has a sliding contact surface that is a flat surface against which the valve element slides, a sealing contact surface that includes a convex curved surface on the opposite side to the sliding contact surface, and a plurality of valve ports that penetrate from the sliding contact surface to the sealing contact surface, and the surface area of ​​the sealing contact surface is larger than the surface area of ​​the sliding contact surface, and the sealing contact surface of the valve seat member is provided in close contact with the inner circumferential surface of the valve body, the valve body has a cylindrical portion, an opening that opens to the side where the drive unit is located, a bottom portion provided on the side opposite to the side where the drive unit is located, and a wall portion erected on the inner peripheral surface of the cylindrical portion between the opening and the bottom portion; the valve seat member has a pair of side end surfaces connecting side end edges of the sliding contact surface and the curved surface, and a pair of tip surfaces that constitute both ends in the axial direction, the curved surface and the side end surfaces constitute the contact surface, one of the pair of tip surfaces is in contact with the bottom portion, and the other of the pair of tip surfaces is in contact with the wall portion. It is characterized by:

[0007] According to the present invention, the valve seat member has a contact surface including a curved surface that is convexly curved opposite to the sliding contact surface. This allows the valve seat member to be thicker and more rigid than a valve seat member made of a thin metal plate. Therefore, even if the valve body deforms due to a pressure difference between inside and outside, the valve seat member can be prevented from deforming as a result of the deformation. Furthermore, since the contact surface including the curved surface of the valve seat member is in close contact with the inner circumferential surface of the cylindrical portion of the valve body, the contact area is larger than that of a valve seat member made of a thin metal plate. This improves the fixing strength of the valve seat member to the valve body and prevents the valve seat member from peeling off from the valve body. Therefore, a sliding switching valve can be provided that improves valve leakage performance by increasing the fixing strength of the valve seat member to the valve body and preventing deformation and peeling of the valve seat member. Furthermore, since the curved surface of the valve seat member can be arranged along the inner surface of the valve body, the thickness of the valve seat member can be increased without changing the size of the entire slide-type switching valve, and this can also prevent the slide-type switching valve from becoming too large. According to the present invention, the valve seat member has a contact surface that contacts the inner circumferential surface of the cylindrical portion of the valve body, one of a pair of tip surfaces that contacts the bottom of the cylindrical portion, and the other of the pair of tip surfaces that contacts the wall portion of the valve body. By bringing the portions of the valve seat member other than the sliding contact surface into contact with the structure of the valve body, the contact area between the valve seat member and the valve body can be increased in the axial direction and in the width direction that intersects with the axial direction, thereby improving the fixing strength of the valve seat member to the valve body. This makes it possible to prevent the valve seat member from peeling off from the valve body due to deformation of the valve body.

[0009] In this case, it is preferable that the opening has a circular inner peripheral surface, and the drive unit is inserted so as to fit into the inner peripheral surface. With this configuration, for example, when the drive unit has a cylindrical outer shape, the drive unit can be easily fitted into the opening to assemble the slide switch valve.

[0010] Preferably, the valve body has a protruding portion that protrudes from the bottom portion toward the opening, and the protruding portion is in close contact with the sliding surface of the valve seat member. With this configuration, the valve seat member can be fixed by being sandwiched between the protruding portion that is in close contact with the sliding surface and the inner peripheral surface of the cylindrical portion that is in close contact with the curved surface, thereby further improving the fixing strength of the valve seat member to the valve body.

[0011] Also, The slide-type switching valve of the present invention is a slide-type switching valve comprising a hollow cylindrical valve body, a valve seat portion provided in the valve body, a valve disc provided inside the valve body so as to be slidable in an axial direction, and a drive portion for driving the valve disc to slide, wherein the valve seat portion has a metal valve seat member integrated by insert molding with a resin forming the valve body, and the valve seat member has a sliding contact surface which is a flat surface against which the valve disc slides, a sealing contact surface which includes a convex curved surface on the opposite side to the sliding contact surface, and a plurality of valve ports extending from the sliding contact surface to the sealing contact surface, the surface area of ​​the sealing contact surface being larger than the surface area of ​​the sliding contact surface, and the sealing contact surface of the valve seat member being provided in close contact with the inner circumferential surface of the valve body, Preferably, the valve port has an expanded diameter portion opening on the side opposite the sliding contact surface and a step extending from the expanded diameter portion toward the inner diameter, and the inner circumferential surface of the expanded diameter portion constitutes a part of the sealing surface. With this configuration, the inner circumferential surface, curved surface, side end surface, and tip end surface of the expanded diameter portion of the valve seat member all come into close contact with the tubular portion of the valve body. Therefore, the portion of the valve seat member extending in the axial direction between the expanded diameter portion and the tip end surface is less likely to displace in the axial direction, thereby further improving the fixing strength of the valve seat member in the axial direction. Furthermore, with this configuration, for example, during insert molding of the valve seat member, a cylindrical pin-shaped mold can be pressed against the step portion to close the valve port, and resin can be injected to mold the valve body. This prevents the resin from entering the valve port or the sliding contact surface.

[0012] Furthermore, it is preferable that the valve seat member has a flat surface parallel to the sliding contact surface on the opposite side to the sliding contact surface, and the flat surface constitutes a part of the tight contact surface. With this configuration, since a flat surface parallel to the sliding contact surface is formed on the opposite side to the sliding contact surface, the curved surface side of the valve seat member can be more easily machined compared to a configuration in which a flat surface is not formed. Specifically, for example, even if a tool such as a drill is pressed against the curved surface side, the tool is less likely to slip, making it easier to drill a hole from the curved surface side to the sliding contact surface side. Therefore, the processability of forming a valve port in the valve seat member can be improved.

[0013] Furthermore, it is preferable that at least a portion of the curved surface, the pair of side end surfaces, and the pair of tip surfaces are roughened. With this configuration, the unevenness of the roughened surface increases the contact area between the resin and the metal, thereby further improving the fixing strength of the valve seat member to the valve body by a so-called anchor effect.

[0014] Preferably, the side of the side end surface where the curved surface is located constitutes a part of the contact surface, and the side where the sliding surface is located is an exposed portion that does not contact the valve body, and the valve body has a guide portion that slides and guides the valve disc, and a space is formed between the guide portion and the exposed portion. With this configuration, even if the valve disc is scraped and foreign matter is generated due to sliding between the valve disc and the valve seat member, the foreign matter can be diverted and contained between the guide portion and the exposed portion. This prevents the valve disc from tilting due to riding on foreign matter, resulting in unintended valve leakage. Furthermore, with this configuration, for example, a part of a mold can be placed in the space between the guide portion and the exposed portion during insert molding of the valve seat member. That is, the valve seat member can be guided by being sandwiched between parts of the mold that abut against each of the pair of side end surfaces, thereby improving the positioning accuracy of the valve seat member relative to the valve body.

[0015] Furthermore, it is preferable that the side end surface has a stepped surface extending outward in a width direction intersecting the axial direction on the side of the curved surface, the stepped surface constituting a part of the contact surface. With this configuration, the stepped surface and the curved surface of the valve seat member are in close contact with or in close contact with the cylindrical portion of the valve body. Therefore, the valve seat member is sandwiched by the cylindrical portion in the thickness direction from the sliding contact surface toward the curved surface, making it more difficult for the valve seat member to displace in that direction, thereby further improving the fixing strength of the valve seat member in that direction.

[0016] Furthermore, the valve seat member is preferably made of a magnetic material. With this configuration, for example, when insert-molding the valve seat member, the valve seat member can be easily fixed to the mold by incorporating a magnet or the like into the mold, and the positioning accuracy of the valve seat member can be easily improved.

[0017] Preferably, the valve body is accommodated with a gap in a housing to which a refrigerant pipe is connected, and the valve port and the refrigerant pipe are capable of communicating with each other through the gap between the valve body and the housing. With this configuration, the housing that accommodates the valve body can improve the pressure resistance of the valve body, allowing the resin constituting the valve body itself to be made thinner. Furthermore, for example, by making the housing out of metal, the refrigerant pipe and the housing can be easily connected by brazing, welding, or the like, thereby avoiding the difficulty of joining a resin valve body and a metal refrigerant pipe, which are made of different materials. Furthermore, with this configuration, the refrigerant pipe is connected to the housing, not directly to the valve body, allowing the valve body to be easily attached and detached from the housing, contributing to improved maintainability, etc. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a slide-type switching valve that improves valve leakage performance by increasing the fixing strength of the valve seat member to the valve body and suppressing deformation and peeling of the valve seat member. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view of a slide-type switching valve according to an embodiment of the present invention, taken along the axial direction of a valve body. [Figure 2] FIG. 3 is a cross-sectional view of the valve body and the valve seat taken along the axial direction of the valve body. [Figure 3] 2 is a cross-sectional view taken along line AA in FIG. 1. [Figure 4] 1A is a perspective view of the valve seat member as seen obliquely from above, FIG. 1B is a side view of the valve seat member, and FIG. 1C is a perspective view of the valve seat member as seen obliquely from below. [Figure 5] FIG. 10 is a cross-sectional view of a valve body and a valve seat portion in a first modified example, taken along a direction perpendicular to the axis of the valve body. [Figure 6] FIG. 6 is an enlarged cross-sectional view of region A in FIG. 5 . [Figure 7] 10(A) and 10(B) are diagrams showing a method for manufacturing a valve body and a valve seat portion in a first modified example. [Figure 8] 10A to 10C are diagrams showing a manufacturing method of the valve body and the valve seat portion in the first modified example. [Figure 9] FIG. 10 is a cross-sectional view of a valve body and a valve seat portion in a second modified example, taken along a direction perpendicular to the axis of the valve body. [Figure 10] FIG. 10 is an enlarged cross-sectional view of region B in FIG. 9 . [Figure 11] FIG. 10 is a cross-sectional view of a valve body and a valve seat portion in a second embodiment, taken along the axial direction of the valve body. [Figure 12] FIG. 12 is an enlarged cross-sectional view of region C in FIG. [Figure 13] FIG. 10 is a perspective view of a valve seat portion in a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described below with reference to Figures 1 to 4. The slide-type switching valve 1 according to this embodiment is a switching valve connected to a compressor, an outdoor heat exchanger, and an indoor heat exchanger in a refrigeration cycle or the like, and switches the flow path of the refrigerant flowing through these devices. The slide-type switching valve 1 includes a hollow cylindrical valve body 10, a valve seat 20 provided within the valve body 10, a valve element 30 provided inside the valve body 10 so as to be slidable in the direction of axis L, a drive unit 40 that drives the valve element 30 to slide, and a housing 50 that accommodates the valve body 10. In the description of this embodiment, the side of the valve body 10 in the direction of axis L on which the drive unit 40 is located will be referred to as one side in the direction of axis L, and will be referred to as one side L1. The side opposite to the one side L1 in the direction of axis L of the valve body 10 will be referred to as the other side, and will be referred to as the other side L2. Furthermore, the direction perpendicular to the axis L and corresponding to the short-side direction of the valve seat member 21 (described later) is referred to as the width direction Y, with one side of the width direction Y being referred to as the left side Y1 and the other side of the width direction Y being referred to as the right side Y2. Furthermore, the depth direction of the valve body 30 is referred to as the vertical direction Z, with one side of the vertical direction Z being referred to as the upper side Z1 and the other side of the vertical direction Z being referred to as the lower side Z2.

[0021] As shown in FIG. 1, the valve body 10 includes a circular bottom wall 11, a cylindrical side wall 12 (cylindrical portion) extending from the periphery of the bottom wall 11 toward one side L1, an opening 12a formed on the one side L1 of the side wall 12, and a valve chamber 13 disposed within the side wall 12. The valve body 10 is formed into a cylindrical shape with a bottom by resin molding using a material such as polyphenylene sulfide (PPS). A D port 14 communicating with the inside and outside of the valve chamber 13 is formed in the bottom wall 11. The D port 14 communicates with the discharge hole of the compressor via a D connection passage 14d extending along the axis L, a D communication passage 53 (described later), and a D joint pipe 53d. As shown in FIG. 2, a plate-shaped protrusion 15 protruding in the axis L toward the opening 12a is formed on the wall surface of the bottom wall 11 facing the valve chamber 13. As shown in FIG. 3, a pair of protrusions 15 are provided with a gap in the width direction Y, and the surfaces facing the lower side Z2 are in close contact with the sliding surfaces 22 of the valve seat member 21 described below.

[0022] An opening 12a with a circular inner peripheral surface is provided at the end of one side L1 of the side wall 12, and communicates with the internal valve chamber 13. A plurality of flow paths communicating the inside and outside of the valve chamber 13 are formed in the wall surface of the side wall 12, namely, an E connection flow path 16, an S connection flow path 17, and a C connection flow path 18, which are arranged in this order from the one side L1 along the axial line L. The E connection flow path 16 communicates with the indoor heat exchanger (evaporator or condenser) via an E switching port 26, an E communication passage 54, and an E joint pipe 54e (described later). The S connection flow path 17 communicates with the suction hole of the compressor via an S port 27, an S communication passage 55, and an S joint pipe 55s (described later). The C connection flow path 18 communicates with the outdoor heat exchanger (condenser or evaporator) via a C switching port 28, a C communication passage 56, and a C joint pipe 56c (described later). 2, a plate-shaped wall portion 19 that protrudes toward the upper side Z1 is formed on the inner circumferential surface of the side wall 12 on the inner circumferential surface of the lower side Z2 (the inner circumferential surface on the side where the E-connection flow path 16, the S-connection flow path 17, and the C-connection flow path 18 are formed). The wall portion 19 is formed between the opening 12a and the E-connection flow path 16. That is, the wall portion 19 stands on the inner circumferential surface of the side wall 12 between the opening 12a and the bottom wall 11. The surface of the wall portion 19 facing the other side L2 is in close contact with the tip surface 25 facing one side L1 of a pair of tip surfaces 25 of a valve seat member 21, which will be described later.

[0023] As shown in FIG. 1 , a connection part 60 is provided at the opening edge of the opening 12a of the valve body 10. The connection part 60 is a metal member that connects the valve body 10 to a case 41a (described later). The connection part 60 includes a substantially cylindrical lower cover 61 and a substantially cylindrical upper cover 62 that is connected to the lower cover 61. The edge of the other side L2 of the lower cover 61 is insert-molded into the valve body 10 in the direction of the axis L. The opening edge of the other side L2 of the upper cover 62 is formed with a radially expanded diameter, and this opening edge of the other side L2 is fixed to the opening edge of one side L1 of the lower cover 61 by welding. Meanwhile, the opening edge of one side L1 of the upper cover 62 is fixed to the opening edge of the other side L2 of the case 41a by welding.

[0024] The valve body 10 and connection part 60 formed in this manner are accommodated in a housing 50. The housing 50 has a central accommodation bore 51 that is coaxial with the axis L and has an inner diameter larger than the outer diameter of the valve body 10. The valve body 10 and connection part 60 are inserted into this accommodation bore 51 in the direction of the axis L with a radial gap formed therebetween. In FIG. 1 , reference symbol G denotes grooves formed at predetermined intervals in a plurality of positions in the direction of the axis L on either the outer circumferential wall of the valve body 10 or the inner circumferential wall of the accommodation bore 51, and reference symbol 50a denotes a sealing member such as an O-ring arranged in the groove G. Reference symbol 50b denotes a retaining ring that abuts against the above-mentioned upper cover 62 to prevent the valve body 10 from moving toward one side L1.

[0025] A D communication passage 53 communicating with the D port 14 and the D connection passage 14d is formed in the bottom wall of the housing 50. A D joint pipe 53d is connected to the D communication passage 53. A side wall of the housing 50 is formed with a plurality of communication passages, namely, an E communication passage 54, an S communication passage 55, and a C communication passage 56, which are respectively connected to the E connection passage 16, the S connection passage 17, and the C connection passage 18, in this order along the axial line L from one side L1. An E joint pipe 54e is connected to the E communication passage 54, an S joint pipe 55s is connected to the S communication passage 55, and a C joint pipe 56c is connected to the C communication passage 56. The E joint pipe 54e, the S joint pipe 55s, and the C joint pipe 56c are refrigerant pipes through which a refrigerant flows. In other words, refrigerant pipes are connected to the housing 50.

[0026] The valve seat portion 20 is a portion on which the valve disc 30 seats and slides, and is configured with a valve seat member 21 installed on the side wall 12 of the valve body 10, on which the E-connection flow path 16, the S-connection flow path 17, and the C-connection flow path 18 are formed. The valve seat portion 20 is formed of a metal member such as a magnetic material, and is fixed and integrated with the side wall 12 of the valve body 10 (the resin that forms the valve body 10) by insert molding. As shown in Fig. 4, the valve seat member 21 has a sliding contact surface 22 as a flat surface against which the valve disc 30 slides, a curved surface 23 that is convexly curved on the side opposite to the sliding contact surface 22, a pair of side end surfaces 24 that connect the side end edges of the sliding contact surface 22 and the curved surface 23, and a pair of tip surfaces 25 that form both end portions in the direction of the axis L.

[0027] The sliding contact surface 22 is a so-called sealing surface and extends in the axial direction L and the width direction Y. The curved surface 23 is curved so as to convex downward Z2. The pair of side end surfaces 24 extend in the vertical direction Z and connect the sliding contact surface 22 and the curved surface 23. As shown in FIG. 3, the curved surface 23 and the pair of side end surfaces 24 are in close contact with the inner circumferential surface of the side wall 12 of the valve body 10. That is, the curved surface 23 and the side end surfaces 24 form a close contact surface a that is in close contact with the inner circumferential surface of the valve body 10. As shown in FIG. 3, the surface area of ​​the close contact surface a is larger than the surface area of ​​the sliding contact surface 22. The pair of tip surfaces 25, like the pair of side end surfaces 24, extend in the vertical direction Z and connect the sliding contact surface 22 and the curved surface 23. As shown in FIG. 2, one of the pair of tip surfaces 25 located on the other side L2 is in close contact with the bottom wall 11 of the valve body 10. Of the pair of tip surfaces 25, the tip surface 25 (the other) located on one side L1 is in close contact with the wall portion 19 of the valve body 10. Rough surfaces are formed on at least parts of the curved surface 23, the pair of side end surfaces 24, and the pair of tip surfaces 25. The rough surfaces are formed using techniques such as chemical treatment, laser irradiation, and sputtering, which increases the contact area with the resin when the valve seat member 21 is insert-molded.

[0028] A plurality of valve ports are formed on the plate surface of the valve seat member 21 (the plate surface of the valve seat portion 20), penetrating from the sliding surface 22 to the curved surface 23. The plurality of valve ports include an E-switching port 26 communicating with the E-connecting flow path 16, an S-port 27 communicating with the S-connecting flow path 17, and a C-switching port 28 communicating with the C-connecting flow path 18. As shown in FIG. 1 , the valve ports 26, 27, and 28 communicate with corresponding refrigerant pipes 54e, 55s, and 56c via the above-mentioned connecting flow paths 16, 17, and 18 and communicating passages 54, 55, and 56. As described above, the inner diameter of the accommodating hole 51 of the housing 50 is larger than the outer diameter of the valve body 10, and thus a radial gap is formed between the valve body 10 and the housing 50. Therefore, the ports 26, 27, 28 can communicate with the refrigerant pipes 54e, 55s, 56c through the gap between the valve body 10 and the housing 50. Specifically, the E switching port 26 communicates with the E joint pipe 54e through the gap between the E connection flow path 16 and the E communication passage 54. The S port 27 communicates with the S joint pipe 55s through the gap between the S connection flow path 17 and the S communication passage 55. The C switching port 28 communicates with the C joint pipe 56c through the gap between the C connection flow path 18 and the C communication passage 56.

[0029] The valve element 30 is made primarily of a resin such as polyphenylene sulfide (PPS) and is provided inside the valve body 10 so as to be slidable in the direction of the axis L. The valve element 30 is configured to switch the communication states of the above-mentioned D port 14, E switch port 26, S port 27, and C switch port 28, and in this embodiment is configured with a valve element main body 31 that slides against the sliding contact surface 22 of the valve seat 20. The valve element main body 31 is formed in a bowl shape that opens toward the sliding contact surface 22, and its interior forms a bowl-shaped recess 32 that serves as a fluid flow path. The opening edge of the valve element main body 31 forms a seal portion 33 that slides against the sliding contact surface 22, and its dimensions in the direction of the axis L and width are set to a size that covers two adjacent ports out of the E switch port 26, the S port 27, and the C switch port 28. At the end of the valve body main body 31 on one side L1, a hook portion 34 is formed that protrudes to the one side L1 and opens to the upper side Z1.

[0030] The hook portion 34 is a portion for connecting the valve element 30 to the actuator 40. The hook portion 34 is sandwiched between two connecting arms 48 of a female screw member 44 (described later) of the actuator 40 and is fixed to the actuator 40 by a fixing pin 49 disposed in the hook-shaped portion and a clip (not shown) that circumferentially surrounds and fastens the connecting arms 48 and the hook portion 34. A stopper 35 that protrudes downward in the direction of the axis L is formed at the end of the other side L2 of the valve element main body 31. The protruding end of the stopper 35 abuts against the surface of the bottom wall 11 of the valve body 10 facing the valve chamber 13, thereby restricting movement of the valve element main body 31 toward the other side L2. A biasing member 36 that biases the valve element 30 toward the valve seat 20 is provided between the tip surface of the top (end of the upper side Z1) of the valve element main body 31 and the inner circumferential surface of the valve body 10. The biasing member 36 is a leaf spring formed by pressing or the like using a metal material such as phosphor bronze. By being biased by this biasing member 36, the seal portion 33 of the valve body 31 is pressed against the sliding contact surface 22, thereby suppressing valve leakage.

[0031] The drive unit 40, which drives the valve element 30 to slide, includes a stepping motor 41 and a linear motion mechanism 42 that converts the rotation of the stepping motor 41 into linear motion and transmits it to the valve element 30. As shown in Fig. 1, the stepping motor 41 includes a case 41a fixed to the opening edge of one side L1 of the top cover 62 (disposed at one end of the valve body 10 in the direction of the axis L) to seal the inside of the drive unit 40, an electromagnetic rotor 41b housed in the case 41a, and an electromagnetic coil 41c that circumferentially surrounds the outer periphery of the electromagnetic rotor 41b with the case 41a in between. The case 41a is formed into a cylindrical shape with a bottom using a thin metal plate, and is positioned so that its central axis is coaxial with the axis L and its opening edge faces the other side L2, and the opening edge is fixed to the opening edge of the one side L1 of the top cover 62 by welding.

[0032] The linear motion mechanism 42 includes a bearing member 42a disposed inside one side L1 of the case 41a, a guide member 42b fixed to the inner peripheral wall of the top cover 62, a drive shaft 43 fixed to the center of the electromagnetic rotor 41b, and a female thread member 44 having a female thread 44a that threadably engages with a male thread 43a formed on the outer peripheral surface of the drive shaft 43. That is, the linear motion mechanism 42 is configured as a screw feed mechanism having a male thread 43a and a female thread 44a that threadably engage with each other. The bearing member 42a is a member that supports the drive shaft 43 rotatably in the direction of the axis L and is formed in a disk shape. The bearing member 42a is inserted into the case 41a so that its central axis is coaxial with the axis L of the valve body 10. A first bearing hole 42a1 that opens toward the other side L2 is formed in the center of the bearing member 42a, which is the axial center of the drive shaft 43. An end portion of one side L1 of the drive shaft 43 is fitted into the first bearing hole 42a1.

[0033] The guide member 42b includes a main body 45 formed in a cylindrical shape with a bottom, and a lid portion 46 that protrudes radially outward from the main body 45 and fits into the opening 12a of the valve body 10. The main body 45 is fixed to the inner peripheral wall of the top lid 62 so that its tip is located on one side L1 and its bottom is located on the other side L2. The main body 45 is arranged so that its central axis is coaxial with the axis L of the valve body 10. With this arrangement, the case 41a, bearing member 42a, and guide member 42b are all arranged so that their central axes are coaxial with the axis L of the valve body 10. A second bearing hole 45a is formed in the center of the main body 45, facing the first bearing hole 42a1 in the direction of the axis L. The end of the drive shaft 43 on the other side L2 is inserted into the second bearing hole 45a.

[0034] A pair of guide holes (not shown) are formed around the second bearing hole 45a in the bottom wall of the main body 45, through which the connecting arm portion 48 of the female screw member 44 is inserted so as to be movable back and forth in the axial direction L. These guide holes are through holes that guide the female screw member 44 back and forth in the axial direction L without rotating it around the axial direction L. The cover portion 46 has a side wall portion 46a extending in the vertical direction Z, and the outer peripheral surface of the side wall portion 46a is fitted into the inner peripheral surface of the opening 12a of the valve body 10. That is, the drive unit 40 is inserted into the valve body 10 so as to be fitted into the inner peripheral surface of the valve body 10. The drive shaft 43 is fixed to the center of the electromagnetic rotor 41b, extends in the axial direction L, and is configured to rotate integrally with the electromagnetic rotor 41b around the axial direction L. As described above, the male thread 43a is formed on the outer peripheral surface of the drive shaft 43. In addition, the end of one side L1 of the drive shaft 43 is inserted into the first bearing hole 42a1, and the end of the other side L2 of the drive shaft 43 is inserted into the second bearing hole 45a, thereby supporting the drive shaft 43 so that it can rotate around the axis L.

[0035] The female thread member 44 includes a cylindrical base end portion 47 housed within the guide member 42b, with its outer peripheral wall sliding against the inner peripheral wall of the guide member 42b, and two connecting arms 48 extending from the base end portion 47 to the other side L2 and passing through the guide holes into the valve chamber 13. The base end portion 47 has a central axis coaxial with the central axis of the guide member 42b. A female thread 44a is formed at the center of the base end portion 47 along the axis L. The female thread 44a is threadedly engaged with the male thread 43a and is capable of moving coaxially along the axis L as the drive shaft 43 rotates. The connecting arms 48 extend from a portion of the periphery of the base end portion 47 through the guide holes to the valve chamber 13. The tip ends of the connecting arms 48 have opposing plate surfaces, and a fixing pin 49 is fixed to the tip ends where the opposing plate surfaces are located, penetrating both plate surfaces in the thickness direction.

[0036] In this configuration, when the stepping motor 41 is driven to rotate the drive shaft 43 about the axis L, the female screw member 44 moves in the direction of the axis L in response to the rotation. As a result, the valve element 30, which is fixed to the connecting arm portion 48 of the female screw member 44, also moves in the direction of the axis L in response to the movement of the female screw member 44. The valve element main body 31 of the valve element 30 switches the communication states of the ports 14, 26, 27, and 28. For example, in the state shown in FIG. 1 , the bowl-shaped recess 32 of the valve element main body 31 connects the E switch port 26 and the S port 27, and outside the valve element main body 31, the D port 14 and the C switch port 28 connect. From here, when the valve body main body 31 moves to the other side L2 by driving the stepping motor 41, the bowl-shaped recess 32 of the valve body main body 31 connects the C switching port 28 and the S port 27, and outside the valve body main body 31, the D port 14 and the E switching port 26 are connected.

[0037] As described above, according to this embodiment, the valve seat member 21 has a contact surface a including the curved surface 23 that is convexly curved opposite to the sliding surface 22. This allows the valve seat member 21 to have a larger wall thickness (dimension in the vertical direction Z) and higher rigidity than a valve seat member 21 made of a thin metal plate. Therefore, even if the valve body 10 is deformed due to a pressure difference between inside and outside, deformation of the valve seat member 21 associated with the deformation can be suppressed. Furthermore, since the contact surface a including the curved surface 23 of the valve seat member 21 is in close contact with the inner circumferential surface of the side wall 12 (cylindrical portion) of the valve body 10, the contact area is larger than that of a valve seat member 21 made of a thin metal plate. This improves the fixing strength of the valve seat member 21 to the valve body 10 and suppresses peeling of the valve seat member 21 from the valve body 10. Therefore, a slide-type switching valve 1 can be provided that improves valve leakage performance by increasing the fixing strength of the valve seat member 21 to the valve body 10 and suppressing deformation and peeling of the valve seat member 21. Furthermore, since the curved surface 23 of the valve seat member 21 can be arranged along the inner surface of the valve body 10, the thickness of the valve seat member 21 can be increased without changing the overall size of the slide-type switching valve 1, and the size of the slide-type switching valve 1 can also be prevented from increasing.

[0038] Furthermore, the valve seat member 21 has a contact surface a in close contact with the inner circumferential surface of the side wall 12 of the valve body 10, a pair of tip surfaces 25 (one of which is located on the other side L2) in close contact with the bottom wall 11, and a pair of tip surfaces 25 (the other of which is located on the one side L1) in close contact with the wall portion 19 of the valve body 10. By having the portions of the valve seat member other than the sliding contact surface 22 in close contact with the structure of the valve body 10, the contact area between the valve seat member 21 and the valve body 10 is increased in the axial direction L and the width direction Y, and the fixing strength of the valve seat member 21 to the valve body 10 can be improved. This makes it possible to prevent the valve seat member 21 from peeling off from the valve body 10 due to deformation of the valve body 10.

[0039] Furthermore, the drive unit 40 is inserted into the valve body 10 so as to fit onto the inner peripheral surface of the valve body 10. With this configuration, for example, when the drive unit 40 has a cylindrical outer shape, the drive unit 40 can be easily fitted into the opening 12a, and the slide type switching valve 1 can be assembled.

[0040] Furthermore, a plate-shaped protrusion 15 protruding in the axial direction L toward the opening 12a is formed on the wall surface of the bottom wall 11 of the valve body 10 on the valve chamber 13 side, and the surface of the protrusion 15 facing the lower side Z2 is in close contact with the sliding surface 22 of the valve seat member 21. Furthermore, the curved surface 23 and the pair of side end surfaces 24 are in close contact with the inner circumferential surface of the side wall 12 of the valve body 10. With this configuration, the valve seat member 21 can be fixed by being sandwiched in the up-down direction Z between the protrusion 15 in close contact with the sliding surface 22 and the inner circumferential surface of the side wall 12 in close contact with the curved surface 23, thereby further improving the fixing strength of the valve seat member 21 to the valve body 10.

[0041] Furthermore, at least a portion of the curved surface 23, the pair of side end surfaces 24, and the pair of tip surfaces 25 are roughened, and the unevenness of the roughened surface increases the contact area between the resin and the metal, thereby further improving the fixing strength of the valve seat member 21 to the valve body 10 through the so-called anchor effect.

[0042] Furthermore, since the valve seat member 21 can be formed from a metal member such as a magnetic material, for example, the valve seat member 21 can be easily fixed to the mold by incorporating a magnet or the like into the mold when insert molding the valve seat member 21, and the positioning accuracy of the valve seat member 21 can be easily improved.

[0043] Furthermore, the valve body 10 and the connection portion 60 are housed in a housing 50. With this configuration, the housing 50 that houses the valve body 10 can improve the pressure resistance of the valve body 10, allowing the resin that constitutes the valve body 10 to be made thinner. Furthermore, for example, by making the housing 50 out of metal, the E joint pipe 54e, the S joint pipe 55s, and the C joint pipe 56c (each a refrigerant pipe) can be easily connected to the housing 50 by brazing, welding, or the like, thereby avoiding the difficulty of joining the resin valve body 10 made of dissimilar materials to the metal refrigerant pipe. Furthermore, with this configuration, the refrigerant pipe is connected to the housing 50 and not directly connected to the valve body 10, allowing the valve body 10 to be easily attached and detached to and from the housing 50, contributing to improved maintainability, etc.

[0044] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes design changes and the like that do not deviate from the gist of the present invention.

[0045] Fig. 5 is a cross-sectional view of the valve body 10 and the valve seat portion 20 in the first modified example taken in a direction perpendicular to the axis L. Fig. 6 is an enlarged cross-sectional view of region A in Fig. 5. In the first modified example, the configuration near both ends of the valve seat member 21 in the width direction Y differs from that of the above-described embodiment. Specifically, a pair of guide portions 12b is formed on the inner peripheral surface of the side wall 12 of the valve body 10, facing each side end surface 24 of the valve seat member 21 with a gap in the width direction Y. The guide portions 12b are formed by wall surfaces that can slidably contact both ends of the above-described valve body 31 in the width direction Y, extend in the direction of the axis L, and slide to guide the valve body 31 (valve body 30) in the direction of the axis L through this sliding contact. 6, in the first modified example, the side end surface 24 of the valve seat member 21 has a lower Z2 (the side with the curved surface 23) portion that forms a close contact portion 24a (close contact surface a) that comes into close contact with the inner circumferential surface of the side wall 12 (valve body 10), and an upper Z1 (the side with the sliding contact surface 22) portion that is an exposed portion 24b that does not come into close contact with the valve body 10. Then, as shown in FIG. 6, a space S is formed between the guide portion 12b and the exposed portion 24b.

[0046] With this configuration, even if the valve body 31 (valve body 30) is scraped and foreign matter is generated due to sliding between the valve body 31 and the valve seat member 21, the foreign matter can be accommodated between the guide portion 12b and the exposed portion 24b. This prevents the valve body 31 from tilting due to riding on the foreign matter, resulting in unintended valve leakage. Furthermore, with this configuration, a part of a mold can be placed in the space S between the guide portion 12b and the exposed portion 24b during insert molding of the valve seat member 21. That is, the valve seat member 21 can be guided by being sandwiched between molds that abut against the pair of side end surfaces 24, thereby improving the positioning accuracy of the valve seat member 21 relative to the valve body 10. This improvement in positioning accuracy will now be described in detail.

[0047] 7 and 8 are diagrams illustrating a manufacturing method for the valve body 10 and the valve seat portion 20 in the first modified example. Here, symbol M denotes a mold center pin primarily used to form the side wall 12 of the valve body 10. The mold center pin M is positioned in the portion where the valve chamber 13 is formed during insert molding of the valve seat member 21. During this process, it is necessary to secure the valve seat member 21 to the mold center pin M. However, since the mold center pin M is often used upright with one side L1 facing upward and the other side L2 facing downward, it is difficult to position the valve seat member 21, as the valve seat member 21 may fall off the mold center pin M due to gravity. If the valve seat member 21 becomes misaligned or falls off during the insert molding process, the performance of the sliding switching valve 1 as a valve may be reduced. Falling off the valve seat member 21 may also damage the mold center pin M. However, in this configuration, the mold center pin M is formed with claws M1 that abut against and clamp the side end surface 24 of the valve seat member 21.

[0048] 7(B) and 8, when the valve seat member 21 is set on the mold center pin M, the valve seat member 21 is clamped by the claws M1 from the outside to the inside in the width direction Y, as shown in FIG. 7(A). This prevents the valve seat member 21 from falling off and enables the valve seat member 21 to be stably positioned. In this case, a magnet or the like (not shown) may be embedded in the mold center pin M at a portion that abuts against the sliding surface 22 of the valve seat member 21. By doing so, if the valve seat member 21 is made of a magnetic material, the valve seat member 21 can be fixed to the mold center pin M by the magnetic force of the magnet, thereby further improving the positioning accuracy of the valve seat member 21.

[0049] Next, a second modified example of the slide-type switching valve 1 will be described. FIG. 9 is a cross-sectional view of the valve body 10 and the valve seat portion 20 in the second modified example, taken along a direction perpendicular to the axis L. FIG. 10 is an enlarged cross-sectional view of region B in FIG. 9. In the second modified example, a step surface 24c that protrudes outward in the width direction Y is formed on the valve seat member 21. The step surface 24c protrudes outward in the width direction Y from the lower end of the close contact portion 24a of each side end face 24. That is, the side end face 24 is provided with the step surface 24c that extends outward in the width direction Y, which intersects with the axis L direction, on the side where the curved surface 23 is located. As shown in FIG. 10, the protruding portion 12c of the side wall 12 of the valve body 10, which protrudes inward in the width direction Y from the lower end of the guide portion 12b, is in close contact with this step surface 24c. That is, the side wall 12 of the valve body 10 is in close contact with the step surface 24c, and the step surface 24c constitutes a part of the close contact surface a. With this configuration, the stepped surface 24c and the curved surface 23 of the valve seat member 21 come into close contact with the side wall 12 of the valve body 10. As a result, the valve seat member 21 is sandwiched between the side wall 12 in the thickness direction, making it more difficult for the valve seat member 21 to displace in that direction, and the fixing strength of the valve seat member 21 in that direction can be further improved.

[0050] Next, a second embodiment of the slide-type switching valve 1 will be described. FIG. 11 is a cross-sectional view of the valve body 10 and the valve seat portion 20 in the second embodiment taken along the axis L. FIG. 12 is an enlarged cross-sectional view of region C in FIG. 11. FIG. 13 is a perspective view of the valve seat portion 20 in the second embodiment. In the second embodiment, the structure in the vicinity of each valve port 26, 27, 28 differs from that in the above-described embodiments and modifications. The shape of the valve seat portion 20 also differs from that in the above-described embodiments and modifications. Specifically, as shown in FIG. 11, the E switching port 26, the S port 27, and the C switching port 28 are provided at their peripheries on the lower side Z2 with an expanded diameter portion 29a that has a larger inner diameter than that of the E switching port 26, the S port 27, and the C switching port 28 and opens to the lower side Z2 (the side opposite the sliding contact surface 22), and a step portion 29b extending from the expanded diameter portion 29a inward in the width direction Y (toward the inner diameter side).

[0051] As shown in FIG. 12, the resin of the side wall 12 (valve body 10), which constitutes the inner wall surface of the E-connection flow path 16, the S-connection flow path 17, or the C-connection flow path 18, is in close contact with the inner circumferential surface of the expanded diameter portion 29a and a portion of the step portion 29b. That is, the inner circumferential surface of the expanded diameter portion 29a constitutes a portion of the close contact surface a. As shown in FIG. 13, a flat surface 23a is formed by cutting out the convex portion of the curved surface 23 at the end of the lower side Z2 of the curved surface 23 of the valve seat member 21. The flat surface 23a is arranged parallel to the sliding surface 22 and extends in the axial direction L and the width direction Y. Although not shown, the flat surface 23a, together with the curved surface 23, is in close contact with the inner circumferential surface of the side wall 12 of the valve body 10. That is, the flat surface 23a constitutes a portion of the close contact surface a.

[0052] With this configuration, the inner circumferential surface of the expanded diameter portion 29a, the curved surface 23, the side end surface 24, and the tip surface 25 of the valve seat member 21 all come into close contact with the side wall 12 of the valve body 10. Therefore, the portion of the valve seat member 21 extending in the axial direction between the expanded diameter portion 29a and the tip surface 25 is less likely to displace in the direction of the axis L, thereby further improving the fixing strength of the valve seat member 21 in the same direction. Furthermore, with this configuration, for example, during insert molding of the valve seat member 21, a cylindrical pin-shaped mold can be pressed against the step portion 29b to close the valve ports 26, 27, and 28, and resin can be injected to mold the valve body 10. This prevents the resin from entering the valve ports 26, 27, and 28 or the sliding contact surface 22.

[0053] In this case, it is preferable to set the outer diameter of the cylindrical pin-shaped mold larger than the inner diameter of the valve ports 26, 27, and 28 and smaller than the inner diameter of the expanded diameter portion 29a. By setting it in this manner, even if the position of the cylindrical pin-shaped mold is slightly misaligned during insert molding of the valve seat member 21, it is possible to prevent the mold from being unable to completely close the valve ports 26, 27, and 28. It is also possible to prevent the mold from unintentionally coming into contact with the expanded diameter portion 29a, thereby preventing distortion of the inner wall shape of the E-connection flow path 16, the S-connection flow path 17, or the C-connection flow path 18.

[0054] Furthermore, since the flat surface 23a parallel to the sliding contact surface 22 is formed on the opposite side of the sliding contact surface 22, the curved surface 23 side of the valve seat member 21 can be processed more easily than in a configuration in which the flat surface 23a is not formed. Specifically, for example, even if a tool such as a drill is pressed against the curved surface 23 side, the tool is less likely to slip, and drilling from the curved surface 23 side to the sliding contact surface 22 side can be performed easily and accurately. Therefore, the processability when forming the valve ports 26, 27, 28 in the valve seat member 21 can be improved.

[0055] The first embodiment, the first modified example, the second modified example, and the second embodiment described above merely illustrate representative aspects of the present invention, and the present invention is not limited thereto. In other words, various modifications can be implemented without departing from the gist of the present invention. For example, the first embodiment, the first modified example, the second modified example, and the second embodiment may be combined, or all of these embodiments and modifications may be combined. Specifically, the valve body 10 may include the protruding portion 15 of the first embodiment, the guide portion 12b of the first modified example, and the protruding portion 12c of the second modified example. Furthermore, the valve seat 20 may include the close contact portion 24a and the exposed portion 24b of the first modified example, the stepped surface 24c of the second modified example, the enlarged diameter portion 29a and the stepped portion 29b of the second embodiment, and the flat surface 23a. The slide-type switching valve 1 may be configured using such a valve body 10 and valve seat 20. Conversely, the protrusion 15, guide portion 12b, and protrusion 12 may be omitted from the valve body 10, and the sealing portion 24a, exposed portion 24b, stepped surface 24c, enlarged diameter portion 29a, step portion 29b, and flat surface 23a may be omitted from the valve seat member 21. [Explanation of symbols]

[0056] a Close contact surface L axis 1 Slide type switching valve 10 Valve body 11 Bottom wall (bottom) 12 Side wall (cylindrical part) 12a opening 19 Wall 20 Valve seat 21 Valve seat member 22 Sliding surface 23 Curved Surface 24 Side end face 25 Tip surface 26 E Switching port (multiple valve ports) 27 S port (multiple valve ports) 28 C switching port (multiple valve ports) 30 Valve body 40 Drive unit

Claims

1. A slide-type switching valve comprising: a hollow cylindrical valve body; a valve seat portion provided in the valve body; a valve element provided inside the valve body so as to be slidable in an axial direction; and a drive portion that drives the valve element to slide, the valve seat portion has a metal valve seat member that is integrated with the resin that forms the valve body by insert molding, the valve seat member has a sliding contact surface which is a flat surface against which the valve body slides, a close contact surface which includes a curved surface which is convexly curved on the opposite side to the sliding contact surface, and a plurality of valve ports which penetrate from the sliding contact surface to the close contact surface, The surface area of ​​the close contact surface is larger than the surface area of ​​the sliding contact surface, The sealing surface of the valve seat member is provided in close contact with the inner circumferential surface of the valve body, The valve body has a cylindrical portion, an opening portion that opens to the side where the drive unit is located, a bottom portion that is provided on the side opposite to the side where the drive unit is located, and a wall portion that stands on the inner circumferential surface of the cylindrical portion between the opening portion and the bottom portion, the valve seat member includes a pair of side end surfaces connecting side end edges of the sliding contact surface and the curved surface, and a pair of tip surfaces constituting both end portions in the axial direction, the curved surface and the side end surface constitute the contact surface, A slide-type switching valve, wherein one of the pair of tip surfaces is provided in close contact with the bottom portion, and the other of the pair of tip surfaces is provided in close contact with the wall portion.

2. 2. The slide-type switching valve according to claim 1, wherein the opening has a circular inner peripheral surface, and the drive portion is inserted so as to fit into the inner peripheral surface.

3. The valve body has a protrusion that protrudes from the bottom toward the opening, 2. The slide-type switching valve according to claim 1, wherein the protrusion is in close contact with the sliding contact surface of the valve seat member.

4. 2. The slide-type switching valve according to claim 1, wherein rough surfaces are formed on at least parts of the curved surface, the pair of side end surfaces, and the pair of tip surfaces.

5. The side end surface has a curved surface that forms a part of the contact surface, and a sliding contact surface that does not contact the valve body and is an exposed portion, 2. The slide-type switching valve according to claim 1, wherein the valve body has a guide portion that slides and guides the valve element, and a space is formed between the guide portion and the exposed portion.

6. The side end surface is provided with a stepped surface extending outward in a width direction intersecting with the axial direction on the side where the curved surface is located, 2. The slide rail according to claim 1, wherein the step surface forms a part of the contact surface. Ride-type switching valve.

7. A slide-type switching valve comprising: a hollow cylindrical valve body; a valve seat portion provided in the valve body; a valve element provided inside the valve body so as to be slidable in an axial direction; and a drive portion that drives the valve element to slide, the valve seat portion has a metal valve seat member that is integrated with the resin that forms the valve body by insert molding, the valve seat member has a sliding contact surface which is a flat surface against which the valve body slides, a close contact surface which includes a curved surface which is convexly curved on the opposite side to the sliding contact surface, and a plurality of valve ports which penetrate from the sliding contact surface to the close contact surface, The surface area of ​​the close contact surface is larger than the surface area of ​​the sliding contact surface, The sealing surface of the valve seat member is provided in close contact with the inner circumferential surface of the valve body, the valve port has an expanded diameter portion that opens to the opposite side of the sliding contact surface, and a step portion extending from the expanded diameter portion toward an inner diameter side, A slide-type switching valve, wherein an inner peripheral surface of the enlarged diameter portion constitutes a part of the sealing surface.

8. the valve seat member has a flat surface parallel to the sliding contact surface on the opposite side to the sliding contact surface, 8. The slide-type switching valve according to claim 7, wherein the flat surface forms a part of the sealing surface.

9. 10. The slide-type switching valve according to claim 1, wherein the valve seat member is made of a magnetic material.

10. The valve body is accommodated with a gap in a housing to which a refrigerant pipe is connected, 10. The slide-type switching valve according to claim 9, wherein the valve port and the refrigerant pipe are capable of communicating with each other through a gap between the valve body and the housing.

Images