Valve device

Abstract

To provide a valve device capable of preventing leakage of fluid to the external at low costs.SOLUTION: A motor-operated valve 1 includes: a valve main body 10; and a fluid passage block 70 having a mounting hole 71 to which the valve main body 10 is inserted, a first flow passage 75, and a second flow passage 77. The valve main body 10 has a metallic valve housing 11, a resin molding portion 14 disposed on an outer peripheral surface of the valve housing 11, and an annular groove 17 in which the seal member 18 is mounted. The annular groove 17 has a recessed cross section formed by a bottom surface composed of the outer peripheral surface of the valve housing 11 and a pair of side surfaces composed of the resin molding portion 14. The seal member 18 is disposed in a state of being closely kept in contact with the bottom surface of the annular groove 17 and an inner peripheral surface of the mounding hole 71.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a valve device.

Background Art

[0002] There is known a valve device (electric valve) including a valve body having a valve port and a valve element inside, and a flow path block (pipe body) having a mounting hole for inserting the valve body and a flow path communicating with the valve port (for example, see Patent Document 1). In the valve device described in Patent Document 1, the valve body includes a metal valve housing (body), a seal member (seal ring) is provided in an annular groove on the circumferential surface of the valve housing, and the seal member is in close contact with the inner circumferential surface of the mounting hole of the flow path block and the annular groove, so that the flow path is sealed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional valve device, since the annular groove of the metal valve housing is formed by cutting, the manufacturing cost increases. On the other hand, as shown in FIG. 9, it is also conceivable to form the valve housing 200 by press working and perform insert molding of the resin 201 on its outer peripheral surface to form the entire annular groove 202 with the resin 201. However, in that case, there is a risk that the valve housing 200 and the resin 201 are separated and the fluid leaks from the separation portion 203 to the outside of the valve device.

[0005] An object of the present invention is to provide a valve device that can prevent external leakage of fluid at low cost.

Means for Solving the Problems

[0006] To solve the aforementioned problems and achieve the objective, the present invention provides a valve device comprising: a valve body having a valve port and a valve element inside; and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, wherein the valve body comprises a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member disposed between the valve body and the flow path block is attached, the annular groove is formed in a concave cross-section by a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, and the sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole The valve housing is provided with a through hole that penetrates inward and outward on the valve port side of the sealing member, and the through hole is provided with a through resin portion that is continuous with the resin molded portion. It is characterized by the following.

[0007] According to this invention, by forming an annular groove between the resin molded part and the outer circumferential surface of the valve housing, there is no need to form the annular groove by machining. Therefore, the manufacturing of the annular groove becomes easier, and the manufacturing cost of the valve device can be reduced. Furthermore, with this configuration, the metal bottom surface of the annular groove and the metal inner circumferential surface of the mounting hole can be directly connected with a sealing member. As a result, even if the resin molded part separates from the metal valve housing and a gap occurs at the contact point between the resin molded part and the valve housing, the sealing performance between the outer circumferential surface of the valve body and the inner circumferential surface of the flow path block can be reliably ensured, and fluid will not leak to the outside. Therefore, a valve device that can prevent external fluid leakage at low cost can be provided. With this configuration, by providing a resin molded portion continuous with the through-hole resin portion in the valve housing, it is possible to suppress positional displacement of the resin molded portion in the axial direction and rotational direction around the axis relative to the valve housing. Furthermore, the through-hole is formed on the valve port side of the sealing member. Therefore, even if the through-hole resin portion peels off and fluid flows from the inside to the outside of the valve housing through the gap between the inner circumferential surface of the through-hole and the through-hole resin portion, the fluid flow can be stopped by the sealing member. Thus, it is possible to suppress the outflow of fluid from the inside of the valve housing through the gap between the valve housing and the flow path block to the outside.

[0009] Furthermore, the resin molded portion includes a first resin molded portion that constitutes one of the sides of the annular groove and a second resin molded portion that constitutes the other side of the annular groove, and the first resin molded portion and the second resin molded portion may be discontinuous.

[0010] Furthermore, it is preferable that the valve body has a resin member provided inside the valve housing, and that the resin member and the first resin molded part are continuously formed by the through-resin part. With this configuration, by continuously forming the resin member and the first resin molded part via the through-resin part, it is possible to suppress positional displacement of the resin member and the first resin molded part in the axial direction and rotational direction around the axis with respect to the valve housing. As a result, since the positional displacement of the resin member with respect to the valve housing is suppressed, for example, if the resin member is equipped with a member that restricts the rotation of the valve body around its axis when subjected to rotational force such as a motor, it is possible to prevent the member from rotating around the axis in accordance with the valve body that is trying to rotate around the axis. Therefore, the function of restricting the rotation of the valve body can be reliably ensured.

[0011] Also, A valve device comprising a valve body having a valve port and a valve element inside, and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, wherein the valve body has a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member disposed between the valve body and the flow path block is attached, the annular groove is formed in a concave cross-section by a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, and the sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole, Preferably, the valve housing and the flow path block are attached to each other in a non-contact state via the resin molded part. In valve devices, the valve housing may be molded from a metal such as stainless steel, and the flow path block may be molded from an aluminum alloy or the like. In this case, if the valve housing and the flow path block come into contact, there is a concern that galvanic corrosion may occur due to the difference in ionization tendency. However, with this configuration, the valve housing and the flow path block can be kept in a non-contact state via the resin molded part. Therefore, even if the valve housing is molded from stainless steel or the like and the flow path block is molded from an aluminum alloy or the like, the occurrence of the aforementioned galvanic corrosion can be suppressed.

[0012] Also, A valve device comprising a valve body having a valve port and a valve element inside, and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, wherein the valve body has a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member disposed between the valve body and the flow path block is attached, the annular groove is formed in a concave cross-section by a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, and the sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole, Valve housing of Fixed to the aforementioned flow channel block do The fixing part , separate from the valve housingIt is preferable that the fixed portion is provided such that at least a part of it is covered by the resin molded portion. With this configuration, at least a part of the fixed portion is covered by the resin molded portion, which prevents direct contact between the fixed portion and the flow path block. For example, if the fixed portion is made of a metal such as stainless steel and the flow path block is made of an aluminum alloy or the like, the occurrence of galvanic corrosion due to contact between the fixed portion and the flow path block can be suppressed.

[0013] Furthermore, it is preferable to provide a resin fastener that maintains the mounting state between the valve housing and the flow path block, wherein the fastener is inserted between the valve housing and the flow path block in the mounting hole in an elastically deformed state and is locked in the mounting hole by a restoring force. With such a configuration, the mounting state between the valve housing and the flow path block can be maintained using the fastener. In this case, since the fastener is locked in the mounting hole by the restoring force after elastic deformation, there is no need to perform complicated work such as screwing when fixing the valve housing and the flow path block. Therefore, the fastener can be easily fixed in the mounting hole. And, when the fastener is locked in the mounting hole, the fastener is interposed between the valve housing and the flow path block, so the fastener can prevent the valve housing and the flow path block from coming into direct contact. For this reason, for example, if the valve housing is made of a metal such as stainless steel and the flow path block is made of an aluminum alloy, the occurrence of galvanic corrosion due to contact between the valve housing and the flow path block can be suppressed.

[0014] Furthermore, the electric valve of the present invention is characterized by being used as the valve device described above. With such a configuration, it is possible to provide an electric valve that can prevent external leakage of fluid at low cost. [Effects of the Invention]

[0015] According to the present invention, a valve device can be provided that can prevent external leakage of fluid at low cost. [Brief explanation of the drawing]

[0016] [Figure 1] Cross-sectional view of the valve device according to the first embodiment of the present invention. [Figure 2] Cross-sectional view showing the valve body and the drive unit of the valve device shown in FIG. 1. [Figure 3] Cross-sectional view showing the flow path block of the valve device shown in FIG. 1. [Figure 4] Enlarged cross-sectional view of the valve device shown in FIG. 1 in region A. [Figure 5] Cross-sectional view of the valve device according to the second embodiment. [Figure 6] Enlarged cross-sectional view of the valve device shown in FIG. 5 in region B. [Figure 7] Plan view of the fixture included in the valve device shown in FIG. 5. [Figure 8] Enlarged cross-sectional view of the valve device according to a modified example of the second embodiment. [Figure 9] Cross-sectional view of a conventional valve device.

Mode for Carrying Out the Invention

[0017] Hereinafter, a first embodiment of a valve device according to the present invention will be described based on FIGS. 1 to 4. The valve device is, for example, an electric valve 1 mounted on a vehicle or the like, and includes a valve body 10, a valve element 40, a drive unit 50, and a flow path block 70. In the following description, the direction along the axis L of the valve body 10 in the drawing is referred to as the "axis L direction", one side in the axis L direction is referred to as "upper side L1", and the other side is referred to as "lower side L2". Further, the direction orthogonal to the axis L direction is referred to as the "radial direction X". These definitions of directions are for the convenience of explanation only, and do not necessarily coincide with the respective directions in the actual use state of the electric valve 1, and do not limit the respective directions in the actual use state of the electric valve 1.

[0018] As shown in Figure 2, the valve body 10 includes a cylindrical valve housing 11. The valve housing 11 is formed in a cylindrical shape by press molding or the like from a metal material such as SUS (stainless steel), and extends in the direction of the axis L. Through holes 12 are formed in the side wall of the valve housing 11, penetrating in the thickness direction (inside and outside the valve housing 11). The through holes 12 are formed intermittently or continuously in the circumferential direction around the axis L, but not in a range that encircles the outer surface of the valve housing 11. A resin, which is integrated with the valve housing 11 by insert molding, is embedded inside the through holes 12, and this resin constitutes a through resin portion 13. An annular resin molded portion 14 is integrally molded on the outer surface of the side wall of the valve housing 11 by insert molding. The resin molded section 14 comprises a first resin molded section 15 that is continuous with the radially outward end of the through-hole resin section 13, and a second resin molded section 16 that is positioned above the first resin molded section 15 at a distance in the axial direction L.

[0019] In other words, the resin molded portion 14 comprises a first resin molded portion 15 and a second resin molded portion 16 that are discontinuous in the axial direction L. The first resin molded portion 15 is positioned on the periphery of the through hole 12 by being continuous with the through resin portion 13. The upper end surface of the second resin molded portion 16 abuts against the lower end surface of the flange portion 24, which will be described later, and this abutment restricts the displacement of the second resin molded portion 16 upward L1. The first resin molded portion 15 and the second resin molded portion 16 may be insert molded simultaneously into the valve housing 11, or one of the first resin molded portion 15 and the second resin molded portion 16 may be molded by insert molding first, and then the other may be insert molded.

[0020] In this case, the resin materials of the first resin molded section 15 and the second resin molded section 16 may be the same or different. For example, one of the first resin molded section 15 and the second resin molded section 16 may be molded from a resin material that is a mixture of PPS (polyphenylene sulfide) and PTFE (polytetrafluoroethylene) to improve sliding properties with other members. Alternatively, the other of the first resin molded section 15 and the second resin molded section 16 may be formed from a resin material that is PPS (polyphenylene sulfide) with added GF (glass fiber) to improve strength and insulation properties.

[0021] Here, by molding the first resin molded part 15 with a resin material that is a mixture of PPS and PTFE as described above, the sliding properties between the valve holder guide hole 32a of the holder guide part 31 (described later) and the valve holder 43 can be improved. As a result, the sliding resistance during operation of the electric valve 1 is reduced, wear of the sliding parts is reduced, and the operational stability of the electric valve 1 is maintained. Thus, a resin material that is a mixture of PPS and PTFE has been mentioned as a resin material that can improve the sliding properties used in the first resin molded part 15, but in addition to this resin material, a resin material that is a mixture of PPS and PTFE with CF (carbon fiber) may be used, or other resin materials such as PEEK (polyether ether ketone) may be used, and the same effects of wear reduction and maintenance of operational stability can be achieved.

[0022] Furthermore, forming the second resin molded portion 16 with a resin material that adds GF to PPS as described above improves both strength and insulation. As a result, when inserting the valve body 10 into the mounting hole 71 of the flow path block 70, the second resin molded portion 16 is less likely to be scraped, the valve housing 11 and the flow path block 70 are insulated, and galvanic corrosion between the valve housing 11 and the flow path block 70 can be suppressed. Thus, while a resin material that adds GF to PPS was mentioned as a resin material that can improve the strength and insulation of the second resin molded portion 16, other resin materials such as PBT (polybutylene terephthalate), PC (polycarbonate), PA (polyamide), and PS (polystyrene) may also be used, and they will have the same effect of suppressing galvanic corrosion as described above.

[0023] By molding the first resin molded section 15 and the second resin molded section 16, an annular groove 17 with a concave cross-section that is recessed in the radial direction X is formed on the outer circumferential surface of the valve housing 11. The bottom surface of the annular groove 17 is made up of the outer circumferential surface of the valve housing 11, the lower L2 side surface of the annular groove 17 is made up of the upper L1 end surface of the first resin molded section 15, and the upper L1 side surface of the annular groove 17 is made up of the lower L2 end surface of the second resin molded section 16. In other words, the annular groove 17 is formed with a concave cross-section by a bottom surface made up of the outer circumferential surface of the valve housing 11 and a pair of side surfaces made up of the resin molded section 14. An annular sealing member 18 is attached to the annular groove 17. The sealing member 18 is an O-ring made of an elastic resin material such as rubber. A first port 19 (valve port) is formed in the portion L2 below the through hole 12 on the outer circumferential surface of the valve housing 11, penetrating in the thickness direction.

[0024] The first port 19 connects the inside of the valve housing 11 to the first flow path 75 of the flow path block 70, which will be described later. Due to the arrangement of the first port 19 and the through hole 12, the through hole 12 penetrates inward and outward on the side of the first port 19 that is closer to the seal member 18. The lower end of the valve housing 11 opens in the direction of the axis L, and the valve seat member 20 is fitted into this opening and fixed to the valve housing 11 in the fitted state by welding, brazing, etc. The valve seat member 20 is formed in a cylindrical shape from a metal material such as SUS (stainless steel) and extends in the direction of the axis L. A second port 21 (valve port) is formed in the center of the valve seat member 20, penetrating in the direction of the axis L. The second port 21 connects the inside of the valve housing 11 to the second flow path 77 of the flow path block 70, which will be described later. A recess 22 that is recessed in the radial direction is formed on the outer circumferential surface of the valve seat member 20. A second sealing member 23 is fitted into the recess 22. The second sealing member 23 is an O-ring made of an elastic resin material such as rubber.

[0025] The upper end of the valve housing 11 is open in the axial direction L, and a flange portion 24 projecting radially outward is formed on the opening edge. A case 25, formed in the shape of a bottomed cylinder from a metal material such as SUS (stainless steel), is airtightly fixed to the upper end surface of the flange portion 24 by welding or the like at its opening edge. The fixing of the case 25 and the fixing of the valve seat member 20 described above make the valve body 10 an airtight pressure vessel. A support portion 26 is attached to the center of the bottom of the case 25 (corresponding to the inner wall surface on the inside of the upper end of the electric valve 1 in Figure 2). The support portion 26 comprises an umbrella portion 26a that extends along the upper inner wall surface of the case 25 and is fixed to the case 25, and a cylindrical portion 26b that projects downward L2 along the axial direction L from the center of the umbrella portion 26a. The cylindrical portion 26b is formed with an opening on the lower side L2, and a bearing 26c is fixed to the inner circumference of the cylindrical portion 26b. The upper end portion 57 of the drive shaft 56, which will be described later, is inserted into the inner circumference of this bearing 26c. Inside the valve housing 11, a cylindrical support member 30 (resin member) made of resin is integrally molded by insert molding.

[0026] The support member 30 is provided with a cylindrical holder guide portion 31 extending in the axial direction L. At the center of the holder guide portion 31, there is a valve holder guide hole 32a extending downward L2 and a valve body guide hole 32b that is continuous with the valve holder guide hole 32a and opens downward L2. The valve holder 43 is inserted into the valve holder guide hole 32a, and the large-diameter portion 42 of the valve body 40 is inserted into the valve body guide hole 32b. The lower L2 portion of the holder guide portion 31 is in close contact with the inner circumferential surface of the valve housing 11. A part of the outer circumferential surface of the lower end portion 33 of the holder guide portion 31 is continuous with the aforementioned through-resin portion 13. At the upper end portion of the holder guide portion 31, there is a cylindrical shaft guide portion 34 that protrudes upward L1. The shaft guide portion 34 is formed coaxially with the holder guide portion 31, and a female thread 35 is formed on its inner circumferential surface, which screws into a male thread 58 formed on the outer circumferential surface of the drive shaft 56.

[0027] The valve body 40 is a needle valve that approaches or separates from the second port 21. The valve body 40 includes a needle portion 41 that is inserted into the second port 21. The needle portion 41 is formed in a columnar shape extending in the axial direction L, and its lower end is formed in a substantially conical shape that tapers towards the lower side L2. A cylindrical large-diameter portion 42 is formed at the upper end of the needle portion 41. The large-diameter portion 42 is formed to be larger in diameter than the needle portion 41 and smaller in diameter than the valve body guide hole 32b, and extends in the axial direction L. This allows the outer circumferential surface of the large-diameter portion 42 of the valve body 40 to slide against the inner circumferential surface of the valve body guide hole 32b. The upper end of the large-diameter portion 42 is inserted into and fixed to the lower end of a cylindrical valve holder 43.

[0028] The valve holder 43 is formed to extend in the axial direction L. The outer diameter of the valve holder 43 is formed to be slightly smaller than the inner diameter of the valve holder guide hole 32a, thereby allowing the outer circumferential surface of the valve holder 43 to slide against the inner circumferential surface of the valve holder guide hole 32a. The radial gap X in the sliding portion between the outer circumferential surface of the valve holder 43 and the inner circumferential surface of the valve holder guide hole 32a is wider than the radial gap X in the sliding portion between the outer circumferential surface of the large diameter portion 42 of the valve body 40 and the inner circumferential surface of the valve body guide hole 32b. Therefore, when the electric valve 1 is operated, the valve body 40 is guided in the axial direction L mainly by sliding in the sliding portion between the outer circumferential surface of the large diameter portion 42 of the valve body 40 and the inner circumferential surface of the valve body guide hole 32b. A through hole 44 is formed at the upper end of the valve holder 43, penetrating in the axial direction L, and the lower end portion 59 of the drive shaft 56 is inserted through the through hole 44. A columnar spring retainer 45 extending in the axial direction L is installed inside the valve holder 43. The lower end of the spring retainer 45 faces the upper end of the large-diameter portion 42 in the axial direction L, and a spring 46 is interposed between the spring retainer 45 and the upper end of the large-diameter portion 42. The installation of the spring 46 biases the needle portion 41 toward the second port 21.

[0029] The drive unit 50 is the part that drives the valve body 40 in the direction of the axis L, and includes a motor 51. The motor 51 includes a stator coil 52 located outside the case 25, and a magnet rotor 53 located inside the case 25, surrounded by the stator coil 52. The stator coil 52 includes a winding section 52a and a yoke and exterior members (not shown). The stator coil 52 is connected to a control unit (not shown), and upon receiving a pulse signal from the control unit, it rotates the magnet rotor 53 counterclockwise or clockwise around the axis L by a predetermined rotation angle corresponding to the pulse signal. The means for fixing the stator coil 52 to the case 25 can be a known type.

[0030] For example, a bracket that straddles the upper end of the case 25 or a bracket that contacts the outer peripheral surface of the lower end of the case may be installed on the stator coil 52, a protrusion may be provided on the bracket, and a dimple may be provided on the case 25 at a position corresponding to the protrusion, thereby fixing the case 25 and the stator coil 52 through the engagement of the protrusion and the dimple. For example, in the structure of Figure 1 of the first embodiment, the protrusion of a bracket (not shown) that straddles the upper end of the case 25 is engaged with a recess 25a (dimple) on the upper outer peripheral surface of the case 25, and in the structure of Figure 5 of the second embodiment described later, the protrusion of a bracket (not shown) that contacts the outer peripheral surface of the lower end of the case 25 is engaged with a recess 25b (dimple) on the lower outer peripheral surface of the case 25. Alternatively, the bracket may be bolted to a fixing plate 79 or the main body of the flow path block 70, which will be described later.

[0031] The magnet rotor 53 is formed in a cylindrical shape by insert molding a bush 55 from a resin material mixed with magnetic powder. A magnet projection 54 is formed on a part of the inner circumferential surface of the upper L1 of the magnet rotor 53, projecting radially inward in the X direction. The bush 55 is installed in the center of the magnet rotor 53 by insert molding, and a drive shaft 56 extending in the direction of the axis L is inserted through the center of the bush 55. The drive shaft 56 is a shaft that rotates together with the magnet rotor 53 around the axis L. The upper end portion 57 of the drive shaft 56 is inserted inside the bearing 26c in the cylindrical portion 26b of the support portion 26 described above, and is supported so as to be rotatable around the axis L and movable back and forth in the direction of the axis L. A male thread 58 is formed on the outer circumferential surface of the drive shaft 56, which is screwed into the female thread 35 of the support member 30. The lower end 59 of the drive shaft 56 is inserted through a through hole 44 in the valve holder 43 and is located inside the valve holder 43. A flange 60 is formed on its outer circumferential surface, projecting radially outward in the X direction. A washer 61 is installed on the upper side L1 of the flange 60, and the flange 60 is sandwiched between the washer 61 and the spring retainer 45 in the axial direction L, thereby connecting the drive shaft 56 to the valve holder 43.

[0032] The drive unit 50 further includes a stopper mechanism 62 that restricts the rotation of the magnet rotor 53. The stopper mechanism 62 includes a cylindrical portion 26b in the support portion 26 of the case 25 described above. A guide portion 64 forming a helical groove is formed on the outer circumferential surface of the cylindrical portion 26b. A slider 65 that screws into the helical groove is installed on the guide portion 64. The slider 65 has a claw portion 66 that protrudes radially outward, and the claw portion 66 is capable of contacting the magnet projection 54 of the magnet rotor 53 around axis L. With this configuration, when the magnet rotor 53 rotates, the slider 65 rotates around axis L in accordance with its rotation, and guided by the guide portion 64, the slider 65 moves to the upper L1 or lower L2. When the slider 65 comes into contact with the cut-up portion of the support portion 26 located at the upper end of the guide portion 64 or with the lower end of the guide portion 64, it becomes unable to rotate any further, and the rotation of the magnet rotor 53 stops.

[0033] Next, the flow path block 70 will be described. The flow path block 70 is a component that constitutes the fluid flow path, and although its overall shape is not shown in the figure, it is formed in a box shape from a metal such as an aluminum alloy. As shown in Figure 3, a mounting hole 71 is formed in the center of the flow path block 70, extending in the direction of the axis L and opening to the upper side L1. The mounting hole 71 is the part into which the valve body 10 is inserted. A stepped portion 72 is formed at the upper end of the inner circumferential surface of the mounting hole 71, recessed to the lower side L2. Below the stepped portion 72, a reduced diameter portion 73 is continuously formed, which is smaller in diameter than the stepped portion 72. Below the reduced diameter portion 73, a tapered portion 73a is formed that is smaller in diameter towards the lower side L2, and a cylindrical first sealed portion 74 is formed on this lower side L2. A first flow path 75 (flow path) extending in the radial direction X is formed in a part of the first sealed portion 74.

[0034] The first flow path 75 has an end on the radially X inner side that communicates with the mounting hole 71, and an end on the radially X outer side that communicates with the outside of the flow path block 70. A cylindrical second sealed portion 76 is formed on the lower side L2 of the first sealed portion 74. The second sealed portion 76 is smaller in diameter than the first sealed portion 74 and extends in the axial direction L. A second flow path 77 (flow path) extending radially X is formed in a part of the second sealed portion 76. The end on the radially X inner side of the second flow path 77 communicates with the mounting hole 71, and an end on the radially X outer side that communicates with the outside of the flow path block 70. An internal threaded portion 78 opening to the upper side L1 is formed at a position radially X outward from the center of the upper surface of the flow path block 70.

[0035] In this embodiment, the valve body 10 and drive unit 50 configured as described above are connected to the flow path block 70 using a fixing plate 79 and bolts 82, as shown in Figure 1. The fixing plate 79 is a plate member that abuts the upper end surface of the flange portion 24 of the valve body 10 and the upper end surface of the flow path block 70. A through hole 80 is formed in the center of the fixing plate 79, through which the case 25 of the valve body 10 can be inserted, in the direction of the axis L. Also, on the upper surface of the fixing plate 79, a bolt hole 81 is formed through in the direction of the axis L, at a position corresponding to the female thread portion 78 of the flow path block 70 described above, through which the bolts 82 can be inserted. When connecting the valve body 10 to the flow path block 70, first, the valve body 10 without the stator coil 52 attached is inserted into the mounting hole 71 of the flow path block 70. This brings the lower end surface of the flange portion 24 of the valve body 10 into contact with the upper end surface of the stepped portion 72 of the flow path block 70.

[0036] Next, while passing the case 25 through the through hole 80, the fixing plate 79 is placed on the upper end surface of the flow path block 70 and the upper end surface of the flange portion 24. Then, in this state, the bolt 82 is inserted through the bolt hole 81 and screwed into the female thread portion 78. During this screwing, the flange portion 24 is pressed against the stepped portion 72 by the fixing plate 79, causing the valve body 10 and the flow path block 70 to become one unit and the valve body 10 to be fixed to the flow path block 70. When the valve body 10 is fixed to the flow path block 70, as shown in Figure 4, a space communicating with the outside is created between the radially outward end face of the second resin molded portion 16, the reduced diameter portion 73 of the flow path block 70, and the radially inward inner surface of the tapered portion 73a. The space between the lower end of the flange portion 24 and the upper surface of the stepped portion 72 of the flow path block 70, and the space between the upper surface of the flange portion 24 and the lower surface of the fixing plate 79 are in contact but not sealed, and fluid (atmosphere) flows through, so the above space constitutes an atmospheric pressure section 83. In this state, the first flow path 75, the first port 19, the inside of the valve body 10, the second port 21, and the second flow path 77 are in communication and form a space, which is a fluid high-pressure section 84 with a higher pressure than the atmospheric pressure section 83.

[0037] Furthermore, in this state, the sealing member 18 is compressed radially X by the outer circumferential surface of the valve housing 11 and the first sealed portion 74 of the flow path block 70. As a result, the sealing member 18 is in close contact with the outer circumferential surface of the valve housing 11 and the first sealed portion 74. That is, the sealing member 18 is in close contact with the bottom surface of the annular groove 17 and the inner circumferential surface of the mounting hole 71. This arrangement of the sealing member 18 prevents the fluid flowing through the high-pressure fluid section 84 from leaking to the atmospheric pressure section 83. Also, in this state, as shown in Figure 1, the second sealing member 23 is compressed radially X by the bottom surface of the recess 22 of the valve seat member 20 and the second sealed portion 76 of the flow path block 70. As a result, the second sealing member 23 is in close contact with the bottom surface of the recess 22 and the second sealed portion 76. Furthermore, this arrangement of the second sealing member 23 prevents the fluid flowing through the high-pressure fluid section 84 from leaking to the second flow path 77 side through the outside of the valve body 10.

[0038] In this configuration, as shown in Figure 1, the first resin molded part 15 and the second resin molded part 16 are interposed between the outer circumferential surface of the valve housing 11 and the first sealed part 74, so that the valve housing 11 and the first sealed part 74 are not in direct contact. Also, although Figure 1 appears to show no gap between the outer circumferential surface of the valve seat member 20 and the second sealed part 76, in reality, a gap exists in that area. With this configuration, the valve housing 11 and the flow path block 70 are attached to each other in a non-contact state via the resin molded part 14. Here, for example, if the valve housing 11 is made of stainless steel or the like and the flow path block 70 is made of aluminum alloy or the like and attached to each other in contact, galvanic corrosion may occur due to the difference in ionization tendencies between the dissimilar metals. However, in this embodiment, since the valve housing 11 and the flow path block 70 are attached to each other in a non-contact state, the occurrence of this galvanic corrosion is suppressed.

[0039] Next, the operation of the electric valve 1 will be described. The electric valve 1 of this embodiment is installed, for example, in a refrigerant flow path provided in a vehicle, and is used to control the flow rate of the refrigerant. First, in the state shown in Figure 1, the needle portion 41 of the valve body 40 is seated on the valve seat member 20, closing the second port 21. In this state, the flow of refrigerant between the first flow path 75 and the second flow path 77 is blocked at the second port 21, stopping the flow of refrigerant. Next, the motor 51 is driven. When the motor 51 is driven, the magnet rotor 53 and the drive shaft 56 rotate around the axis L. Due to this rotation, the male screw 58 of the drive shaft 56 is screwed into the female screw 35 of the support member 30, and the magnet rotor 53 and the drive shaft 56 move to the upper side L1. Then, as the drive shaft 56 moves to the upper L1, the valve holder 43 is pulled up to the upper L1 within the valve holder guide hole 32a. At the same time, the outer circumferential surface of the large diameter portion 42 of the valve body 40 slides against the inner circumferential surface of the valve guide hole 32b as it is pulled up to the upper L1, and in conjunction with this, the needle portion 41 separates from the second port 21 and moves to the upper L1.

[0040] When the needle portion 41 moves away from its seat, the second port 21 opens, and the first passage 75, the first port 19, the inside of the valve body 10, the second port 21, and the second passage 77 become connected, allowing refrigerant to flow through this connected section. At this time, as long as the needle portion 41 is located inside the second port 21, the gap between the outer surface of the needle portion 41 and the inner surface of the second port 21 increases as the needle portion 41 moves away from the second port 21, and the flow rate of refrigerant gradually increases. When the needle portion 41 is located outside the second port 21, the opening of the second port 21 becomes maximum, and thereafter the flow rate of refrigerant remains constant even if the valve body 40 rises. When the slider 65 of the stopper mechanism 62 contacts the cut-up portion of the support portion 26 located at the upper end of the guide portion 64, the rotation of the magnet rotor 53 is restricted, stopping the rise of the valve body 40. Subsequently, when the magnet rotor 53 is rotated in the reverse direction, the magnet rotor 53 and the drive shaft 56 move to the lower L2 while rotating around the axis L, and the valve body 40 moves to the lower L2 in conjunction with this, and the needle portion 41 seats on the valve seat member 20. This seating closes the second port 21 once again.

[0041] As described above, according to the first embodiment, the annular groove 17 is formed by the resin molded part 14 and the outer circumferential surface of the valve housing 11, eliminating the need to form the annular groove 17 by cutting. This makes it easier to manufacture the annular groove 17 and reduces the manufacturing cost of the electric valve 1 (valve device). Furthermore, with this configuration, the metal bottom surface of the annular groove 17 and the metal inner circumferential surface of the mounting hole 71 can be directly connected by the sealing member 18. Therefore, even if a part of the resin molded part 14 peels off from the metal valve housing 11 and a gap occurs at the contact point between the resin molded part 14 and the valve housing 11, the sealing performance between the outer circumferential surface of the valve body 10 and the inner circumferential surface of the flow path block 70 can be reliably ensured, preventing fluid leakage to the outside. Thus, an electric valve 1 (valve device) that can prevent external fluid leakage at low cost can be provided.

[0042] Furthermore, by providing a resin molded portion 14 continuously with the through-hole resin portion 13 provided in the through-hole 12 of the valve housing 11, positional displacement of the resin molded portion 14 in the axial L direction and rotational direction around the axis L relative to the valve housing 11 can be suppressed. Also, the through-hole 12 is formed on the first port 19 (valve port) side of the sealing member 18. Therefore, even if the through-hole resin portion 13 peels off from the through-hole 12 and fluid flows from the inside to the outside of the valve housing 11 through the gap between the inner circumferential surface of the through-hole 12 and the through-hole resin portion 13, the flow of that fluid can be stopped by the sealing member 18. Thus, it is possible to suppress the outflow of fluid from the inside of the valve housing 11 to the outside through the gap between the valve housing 11 and the flow path block 70.

[0043] Furthermore, by forming the support member 30 (resin member) and the first resin molded part 15 continuously via the through-hole resin part 13, positional displacement of the support member 30 and the first resin molded part 15 in the axial direction L and rotational direction around the axis L relative to the valve housing 11 can be suppressed. As a result, since the positional displacement of the support member 30 relative to the valve housing 11 is suppressed, for example, if the support member 30 is equipped with a holder guide part 31 that restricts the rotation of the valve body 40, which is subjected to rotational force from a motor or the like, around the axis L, it is possible to prevent the holder guide part 31 from rotating around the axis L in accordance with the valve body 40 which is trying to rotate around the axis L. Therefore, the function of restricting the rotation of the valve body 40 can be reliably ensured.

[0044] Furthermore, in this embodiment, the valve housing 11 and the flow path block 70 were attached to each other in a non-contact state via the resin molded part 14. In the electric valve 1, the valve housing 11 may be molded from a metal such as stainless steel, and the flow path block 70 may be molded from an aluminum alloy or the like. In this case, if the valve housing 11 and the flow path block 70 come into contact, there is a concern that galvanic corrosion may occur due to the difference in ionization tendency. However, with this configuration, the valve housing 11 and the flow path block 70 can be kept in a non-contact state via the resin molded part 14. Therefore, even if the valve housing 11 is molded from stainless steel or the like and the flow path block 70 is molded from an aluminum alloy or the like, the occurrence of the aforementioned galvanic corrosion can be suppressed.

[0045] Next, a second embodiment of the present invention will be described. Figure 5 is a cross-sectional view of the electric valve 100 (valve device) of the second embodiment. Figure 6 is an enlarged cross-sectional view of region B of the electric valve 100 shown in Figure 5. Figure 7 is a plan view of the push nut 90 (fastener) provided in the electric valve 100 of the second embodiment. The electric valve 100 includes a flange member 27 (fixing part) provided separately from the valve housing 11'. The flange member 27 is a part for fixing the valve housing 11 to the flow path block 70, and as shown in Figure 5, it is composed of a cylindrical part 28 that covers the outer circumferential surface of the valve housing 11 and a flange part 29 that is continuous with the upper end of the cylindrical part 28 and protrudes radially outward in the X direction. The flange member 27 is fixed to the valve housing 11 by welding or brazing. In the second embodiment, with the flange part 29 fixed to the valve housing 11 completed, the first resin molded part 15' and the second resin molded part 16' are insert molded. The first resin molded portion 15' is continuous with the through-resin portion 13 and is molded from the lower end surface of the cylindrical portion 28 to the radially outward end surface of the cylindrical portion 28.

[0046] The second resin molded portion 16' is molded from the radially outward end face of the flange portion 29 to the lower surface of the flange portion 29 and the radially outward end face of the cylindrical portion 28. While the second resin molded portion 16' may be molded to cover a portion of the flange portion 29, the structure of the second resin molded portion 16' is not limited to this. Figure 8 is an enlarged cross-sectional view of an electric valve 100 according to a modified example of the second embodiment. As shown in Figure 8, the second resin molded portion 16'a is molded across the upper surface of the flange portion 29, the radially outward end face of the flange portion 29, and the lower surface of the flange portion 29. Thus, it is sufficient that at least a portion of the outer surface of the flange member 27 (fixed portion) is covered by the resin molded portion 14.

[0047] An annular groove 17' is formed between the radially outward end face of the cylindrical portion 28 (the outer circumferential surface of the valve housing 11), the upper surface of the first resin molded portion 15', and the lower end face of the second resin molded portion 16'. The annular groove 17' corresponds to the annular groove 17 of the first embodiment, and a sealing member 18 is attached to the annular groove 17'. The support member 30' of the second embodiment has a shaft guide portion 34' that extends upward L1 from the upper end of the holder guide portion 31. The shaft guide portion 34' corresponds to the shaft guide portion 34 of the first embodiment, but in the second embodiment, a spiral guide portion 64' is formed on the outer circumferential surface of the shaft guide portion 34'. A slider 65 is installed on the guide portion 64'. The claw portion 66 of the slider 65 abuts against the magnet projection 54 of the magnet rotor 53. That is, in the second embodiment, the support member 30 is provided with the stopper mechanism 62 described above.

[0048] As shown in Figure 6, the mounting hole 71' in the flow path block 70' of the second embodiment has a mounting recess 85 and a mounting projection 86. The mounting recess 85 is continuous with the upper end of the stepped portion 72 and is recessed radially outward X over the entire circumference around the axis L. The mounting projection 86 protrudes radially inward X from the upper end of the mounting recess 85 over the entire circumference around the axis L. The electric valve 100 of the second embodiment is equipped with a push nut 90 (fastener). The push nut 90 is a component for maintaining the mounting state between the valve body 10' and the flow path block 70', and in this embodiment, for example, it is formed in a cylindrical shape using a resin material. The push nut 90 comprises a cylindrical body portion 91 that covers the valve housing 11 in the circumferential direction, and a flange portion 92 that protrudes radially outward X from the upper end of the body portion 91. A locking projection 93 that protrudes radially outward X is formed on the body portion 91.

[0049] As shown in Figure 7, a split portion 94 is formed in a part of the flange portion 92, extending to the body portion 91 when viewed from the direction of the axis L. The split portion 94 is formed at a predetermined angle θ around the axis L when the flange portion 92 is viewed from the direction of the axis L. Due to the formation of the split portion 94, the body portion 91 is elastically deformable radially inward X. The locking projection 93 is formed with an outer diameter larger than the inner diameter of the mounting projection 86 of the flow path block 70 in the state before the body portion 91 is elastically deformed. The valve body 10' is attached to the flow path block 70 as follows. First, the valve body 10' without the stator coil 52 attached is inserted into the mounting hole 71' of the flow path block 70'. This causes the portion of the second resin molded portion 16' that covers the lower surface of the flange portion 29 to come into contact with the upper end surface of the stepped portion 72 of the flow path block 70', as shown in Figure 6.

[0050] Then, in this state, the body 91 of the push nut 90 is elastically deformed radially inward and inserted between the valve housing 11 and the flow path block 70. At this time, due to the elastic deformation, the radially outward end of the locking projection 93 overcomes the mounting projection 86 of the flow path block 70. After the insertion of the push nut 90 is complete, the body 91 returns to its original state before elastic deformation. Due to this restoration, the locking projection 93 fits into the mounting recess 85 of the flow path block 70 and is pressed against the mounting recess 85 by the restoring force. In this state, the locking projection 93 and the mounting projection 86 engage and lock together, restricting the displacement of the push nut 90 upward L1. When the installation of the push nut 90 is complete, the outer circumferential surface of the flange member 27 (valve housing 11) and the first sealed portion 74 of the flow path block 70 compress the seal member 18 radially inward. As a result, the sealing member 18 is in close contact with the outer circumferential surface of the flange member 27 and the first sealed portion 74.

[0051] In this case, the first resin molded part 15' and the second resin molded part 16' are interposed between the flange member 27 and the flow path block 70, so that the valve housing 11 and the flow path block 70 are not in direct contact. As a result, even if the valve housing 11 is made of stainless steel or the like and the flow path block 70 is made of aluminum alloy or the like, electrolytic corrosion due to the difference in ionization tendencies of the dissimilar metal pipes can be prevented. In this case, as in the second embodiment shown in Figure 6, if the entire outer surface of the flange member 27 is not covered by the second resin molded part 16, then if the push nut 90 is made of resin, resin will be interposed between the valve housing 11 and the flow path block 70 in the portion from the lower end of the first resin molded part 15 to the upper end of the push nut 90. Therefore, direct contact between the valve housing 11 and the flow path block 70 in that portion can be reliably prevented, and the above-mentioned electrolytic corrosion can be prevented.

[0052] On the other hand, as in the modified version of the second embodiment, if the entire outer surface of the flange member 27 is covered with the second resin molded part 16, even if the push nut 90 is formed from a metal material, the flange member 27 and the flow path block 70 do not come into direct contact, so the push nut 90 does not necessarily have to be made of a resin material. Thus, the push nut 90 can be made from various materials while taking into consideration its relationship with other components such as the valve body 10'. For example, the push nut 90 may be made from a metal material, or it may be made from a resin material, or it may be made by coating it with resin after being made from a metal material, or by insert molding with resin.

[0053] According to the second embodiment and its modified form, at least a portion of the flange member 27 (fixing portion) is covered by the resin molded portion 14, thereby preventing direct contact between the flange member 27 and the flow path block 70. For example, if the flange member 27 is made of a metal such as stainless steel and the flow path block 70' is made of an aluminum alloy, the occurrence of galvanic corrosion due to contact between the flange member 27 and the flow path block 70' can be suppressed. Furthermore, with this configuration, the mounting state between the valve housing 11' and the flow path block 70' can be maintained using a push nut 90 (fastener). In this case, the push nut 90 is locked into the mounting hole 71' by the restoring force after elastic deformation, so there is no need to perform complicated work such as screwing when fixing the valve housing 11' and the flow path block 70'. Therefore, the push nut 90 can be easily fixed into the mounting hole 71'.

[0054] Furthermore, when the push nut 90 is locked in the mounting hole 71', the push nut 90 is interposed between the valve housing 11' and the flow path block 70', thus preventing direct contact between the valve housing 11' and the flow path block 70'. For this reason, for example, if the valve housing 11' is made of a metal such as stainless steel and the flow path block 70' is made of an aluminum alloy or the like, the occurrence of galvanic corrosion due to contact between the valve housing 11' and the flow path block 70' can be suppressed.

[0055] Although embodiments and modified examples of the valve device have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and any design changes, etc., that do not depart from the gist of the present invention are also included in the present invention. For example, in this embodiment, electric valve 1 and electric valve 100 are given as examples of valve devices, but electric valve 1 and electric valve 100 also include, for example, an electronic expansion valve that opens and closes the second port 21 with a stepping motor. Furthermore, the valve device is not limited to electric valve 1 and electric valve 100, but may also be a solenoid valve that moves a plunger back and forth with an electromagnetic coil, or a manual valve that moves the valve body manually. [Explanation of Symbols]

[0056] 1. Electric valve (valve device) 10 Valve body 11 Valve housing 14 Resin molding section 17 Annular groove 18 sealing member 19. First port (valve port) 21 Second port (valve port) 40 valve body 70 Flow channel block 71 Mounting holes 75 First channel (channel) 77 Second channel (channel)

Claims

1. A valve device comprising a valve body having a valve port and a valve element inside, and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, The valve body comprises a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member, which is positioned between the valve body and the flow path block, is attached. The annular groove is formed with a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, The sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole. The valve device is characterized in that the valve housing is provided with a through hole that penetrates inward and outward on the valve port side of the sealing member, and the through hole is provided with a through resin portion that is continuous with the resin molded portion.

2. The valve device according to claim 1, wherein the resin molded portion comprises a first resin molded portion that constitutes one of the sides of the annular groove and a second resin molded portion that constitutes the other of the sides of the annular groove, and the first resin molded portion and the second resin molded portion are discontinuous.

3. The valve device according to claim 2, wherein the valve body has a resin member provided inside the valve housing, and the resin member and the first resin molded portion are continuously formed by the through-resin portion.

4. A valve device comprising a valve body having a valve port and a valve element inside, and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, The valve body comprises a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member, which is positioned between the valve body and the flow path block, is attached. The annular groove is formed with a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, The sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole. A valve device characterized in that the valve housing and the flow path block are attached to each other in a non-contact state via the resin molded part.

5. A valve device comprising a valve body having a valve port and a valve element inside, and a flow path block having a mounting hole into which the valve body is inserted and a flow path communicating with the valve port, The valve body comprises a metal valve housing, a resin molded portion provided on the outer circumferential surface of the valve housing, and an annular groove into which a sealing member, which is positioned between the valve body and the flow path block, is attached. The annular groove is formed with a bottom surface formed on the outer circumferential surface of the valve housing and a pair of side surfaces formed on the resin molded portion, The sealing member is provided in close contact with the bottom surface of the annular groove and the inner circumferential surface of the mounting hole. A valve device characterized in that a fixing portion for fixing the valve housing to the flow path block is provided separately from the valve housing, and at least a part of the fixing portion is covered by the resin molded portion.

6. The valve housing and the flow path block are equipped with a resin fastener to maintain their mounting state, The valve device according to any one of claims 1 to 5, characterized in that the fastener is inserted between the valve housing and the flow path block in the mounting hole in an elastically deformed state and is locked in the mounting hole by a restoring force.

7. An electric valve used as a valve device according to any one of claims 1 to 5.

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