Electric valve, valve device, and manufacturing method of stator unit

Abstract

Provided are a small electric valve, a valve device, and a manufacturing method for a stator unit of the electric valve and the valve device, which can inhibit the stator unit from falling off from a valve body assembly. A valve body assembly (5) of an electric valve (1) has a rotor housing (30) and a rotor (35) arranged inside the rotor housing (30). A stator unit (8) has a metal inner housing (60), a synthetic resin outer housing (80), and a stator (90). A peripheral wall portion (61) and a bottom wall portion (62) of the inner housing (60) are arranged inside the rotor (35). An annular portion (63) of the inner housing (60) is engaged with an upper end of the rotor housing (30). The stator (90) is embedded in a support portion (84) of the outer housing (80), and the support portion (84) is integrally formed with the stator (90) and the inner housing (60).

Description

Technical Field

[0001] This invention relates to an electric valve, a valve device, and a method for manufacturing a stator unit for the electric valve and the valve device. Background Technology

[0002] Patent document 1 discloses an example of a conventional electric valve. The electric valve has a valve body, a valve core, a housing, a magnetic rotor, and a stator unit containing a stator. The housing has a cylindrical shape and is joined to the valve body. The magnetic rotor is disposed inside the housing. The stator is disposed outside the housing. The magnetic rotor and stator constitute an electric motor. When the magnetic rotor rotates, the valve core moves.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-83453

[0006] The technical problem that the invention aims to solve

[0007] The electric valve in Patent Document 1 is used, for example, for Figure 10 The valve assembly 803 is shown. The valve assembly 803 has multiple electrically operated valves 801 and a flow path block 850. The flow path block 850 has a cuboid shape and a mounting surface 851 for arranging the multiple electrically operated valves 801. The stators of the electrically operated valves 801 are located on the outside of the housing, therefore having a large outer diameter and requiring a large space for arranging the electrically operated valves 801. Therefore, a relatively large mounting surface 851 is required in the flow path block 850.

[0008] By arranging the stator inside the magnetic rotor, the size of the electric valve can be reduced. Figure 11 The electric valve 901 is shown as an example of this electric valve. The electric valve 901 has a valve body assembly 905 and a stator unit 908.

[0009] The valve body assembly 905 includes a valve body 910, a valve core 920, a rotor housing 930, a magnetic rotor 935, a drive component 950, and an inner housing 960. The rotor housing 930 is mounted on the valve body 910. The magnetic rotor 935 has a cylindrical shape and is disposed inside the rotor housing 930. The drive component 950 is coaxially connected to the magnetic rotor 935. When the drive component 950 rotates together with the magnetic rotor 935, the valve core 920 moves in the vertical direction. The inner housing 960 has a peripheral wall portion 961, a bottom wall portion 962 connected to the lower end of the peripheral wall portion 961, and an annular portion 963 connected to the upper end of the peripheral wall portion 961. The peripheral wall portion 961 and the bottom wall portion 962 are disposed inside the magnetic rotor 935. The annular portion 963 engages with the upper end of the rotor housing 930.

[0010] The stator unit 908 has a housing 980 and a stator 990. The housing 980 has a cylindrical support portion 984, into which the stator 990 is embedded. The support portion 984 is disposed inside the peripheral wall portion 961 of the inner housing 960, and the magnetic rotor 935 and the stator 990 are radially opposed to each other across the inner housing 960. The magnetic rotor 935 and the stator 990 constitute a stepper motor 998. A protrusion provided on the inner peripheral surface of the peripheral wall portion 961 engages with a recess provided on the outer peripheral surface of the support portion 984, preventing the support portion 984 from detaching from the inner housing 960.

[0011] However, there is a concern that when the plug is removed from the connector portion 987 of the housing 980, or when vibration is applied to the electric valve 901, the support portion 984 may detach from the inner housing 960, and the stator unit 908 may detach from the valve body assembly 905. Summary of the Invention

[0012] Therefore, the object of the present invention is to provide a small electric valve, a valve device, and a method for manufacturing a stator unit for the electric valve and the valve device, which can suppress the situation where the stator unit detaches from the valve body assembly.

[0013] Technical means for solving technical problems

[0014] To achieve the above objectives, an electric valve according to one aspect of the present invention includes a valve body assembly and a stator unit. The electric valve is characterized in that the valve body assembly has a cylindrical rotor housing mounted on the valve body and a cylindrical magnetic rotor disposed inside the rotor housing. The stator unit has a synthetic resin outer shell, a metal inner shell, and a stator. The inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion whose inner periphery is connected to a second end of the peripheral wall portion. The outer periphery of the annular portion is engaged with one end of the rotor housing. The peripheral wall portion and the bottom wall portion are disposed inside the magnetic rotor. The outer shell has a cylindrical support portion disposed inside the peripheral wall portion. The stator is embedded in the support portion, and the support portion is integrally formed with the stator and the inner shell.

[0015] In this invention, it is preferred that the peripheral wall portion has a through hole, and a protrusion disposed in the through hole is provided on the outer peripheral surface of the support portion.

[0016] In this invention, preferably, the outer casing also has a ring portion disposed on the outer side of the peripheral wall portion, the ring portion being connected to the protrusion.

[0017] In this invention, preferably, the outer diameter of the ring is the same as the inner diameter of the rotor housing, and the outer circumferential surface of the ring is in contact with the inner circumferential surface of the rotor housing.

[0018] In this invention, it is preferred that a recess is provided on the inner peripheral surface of the peripheral wall portion and a protrusion disposed in the recess is provided on the outer peripheral surface of the support portion; or, a recess is provided on the outer peripheral surface of the support portion and a protrusion disposed in the recess is provided on the inner peripheral surface of the peripheral wall portion.

[0019] In this invention, preferably, the outer shell also has a circular plate-shaped base, the support portion is connected to one side of the base, the one side is connected to the annular portion, and the diameter of the one side is smaller than the outer diameter of the annular portion.

[0020] To achieve the above objectives, another aspect of the present invention relates to a valve device comprising: the electric valve; and a flow path block having a mounting surface for configuring the electric valve.

[0021] To achieve the above objectives, another aspect of the present invention relates to a method for manufacturing a stator unit, the stator unit having a synthetic resin outer shell, a metal inner shell, and a stator. The method is characterized in that the inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion with its inner periphery connected to a second end of the peripheral wall portion. The outer shell has an outer shell body, the outer shell body having a cylindrical support portion disposed inside the peripheral wall portion. The stator is disposed inside the peripheral wall portion, and the inner shell is disposed in the cavity of an injection mold. Synthetic resin is injected into the cavity to form the outer shell body.

[0022] To achieve the above objectives, another aspect of the present invention relates to a method for manufacturing a stator unit, the stator unit having a synthetic resin outer shell, a metal inner shell, and a stator. The method is characterized in that the inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion with its inner periphery connected to a second end of the peripheral wall portion. The outer shell has an outer shell body, the outer shell body having a cylindrical support portion disposed inside the peripheral wall portion. The stator is disposed inside the peripheral wall portion, and the inner shell is disposed in the cavity of a casting mold. Synthetic resin is injected into the cavity to form the outer shell body.

[0023] The effects of the invention

[0024] According to the present invention, the valve body assembly has a magnetic rotor disposed inside the rotor housing. The stator unit has a housing, an inner housing, and a stator. The peripheral wall and bottom wall of the inner housing are disposed inside the magnetic rotor, and the annular portion of the inner housing is joined to one end of the rotor housing. The stator is embedded in a support portion of the housing, which is disposed inside the peripheral wall portion. The support portion is integrally formed with the stator and the inner housing. Thus, the support portion is firmly joined to the inner housing, which is joined to the rotor housing, and the possibility of the support portion detaching from the inner housing can be suppressed. Therefore, the electric valve can be reduced in size, and the possibility of the stator unit detaching from the valve body assembly can be suppressed. Attached Figure Description

[0025] Figure 1 This is a front view of the electric valve according to the first embodiment of the present invention.

[0026] Figure 2 yes Figure 1 A top view of the electric valve.

[0027] Figure 3 yes Figure 1 Bottom view of the electric valve.

[0028] Figure 4 It is along Figure 1 A cross-sectional view along line IV-IV.

[0029] Figure 5 yes Figure 1 A cross-sectional view of the valve body assembly of an electric valve.

[0030] Figure 6 yes Figure 1 A cross-sectional view of the stator unit of an electric valve.

[0031] Figure 7 It means Figure 6 A cross-sectional view of the structure of the first modified example of the stator unit.

[0032] Figure 8 It means Figure 6 A cross-sectional view of the structure of the second modified example of the stator unit.

[0033] Figure 9 This is a cross-sectional view of the valve device according to the second embodiment of the present invention.

[0034] Figure 10 This is a top view of a conventional valve device.

[0035] Figure 11 This is a cross-sectional view of a conventional electric valve. Detailed Implementation

[0036] (First Embodiment)

[0037] The following is for reference Figures 1 to 8 The electric valve according to the first embodiment of the present invention will be described. The electric valve according to this embodiment is used, for example, in an automotive air conditioner to control the refrigerant flow.

[0038] Figure 1 , Figure 2 and Figure 3 These are the front view, top view, and bottom view of the electric valve involved in the first embodiment of the present invention. Figure 4 It is along Figure 1 A cross-sectional view along line IV-IV. Figure 4 This is a cross-sectional view along the axis L of the electric valve. Figure 5 yes Figure 1 A cross-sectional view of the valve body assembly of an electric valve. Figure 6 yes Figure 1 A cross-sectional view of the stator unit of an electric valve. Figure 7 It means Figure 6 A cross-sectional view of the structure of the first modified example of the stator unit. Figure 8 It means Figure 6 The diagram shows a cross-sectional view of the structure of a second modified example of the stator unit. In each figure, the X direction indicated by arrow X is the left-right direction, the Y direction indicated by arrow Y is the front-back direction, and the Z direction indicated by arrow Z is the up-down direction (axis L direction). The side with the "X" in arrow X is the right direction, the side with the "Y" in arrow Y is the front direction, and the side with the "Z" in arrow Z is the up direction.

[0039] like Figures 1-4 As shown, the electric valve 1 involved in the first embodiment has a valve body assembly 5 and a stator unit 8.

[0040] like Figure 4 As shown, the valve body assembly 5 includes a valve body 10, a valve core 20, a rolling bearing 25, a rotor housing 30, a rotor 35, and a drive component 50.

[0041] The valve body 10 has a main component 11, a sleeve 18 and a valve core support plate 19.

[0042] The main component 11 is made of metal such as aluminum alloy. The main component 11 has a valve chamber 12, a valve port 13, a valve seat 14, a first connection passage 15, a second connection passage 16, and a mounting hole 17.

[0043] The main body component 11 has a head 11a. The head 11a has a hexagonal shape and is disposed at the upper end of the main body component 11. A manufacturing tool for rotating the main body component 11 about axis L is mounted on the head 11a.

[0044] Valve port 13 is connected to valve chamber 12. Valve port 13 is surrounded by valve seat 14 within valve chamber 12. First connection passage 15 extends from valve chamber 12 in the left-right and front-back directions. Second connection passage 16 extends downward from valve port 13.

[0045] Mounting hole 17 is disposed on the upper surface 11c of the main body component 11. Mounting hole 17 is connected to valve chamber 12. The main body component 11 has a retaining surface 11d. Retaining surface 11d is an upward-facing annular plane. Retaining surface 11d is disposed at the connection between valve chamber 12 and mounting hole 17.

[0046] The main body component 11 has an external thread 11f and an internal thread 11g. The external thread 11f is disposed on the outer peripheral surface of the main body component 11. The internal thread 11g is disposed on the inner peripheral surface of the mounting hole 17.

[0047] The sleeve 18 is made of synthetic resin or metal. The sleeve 18 integrally comprises a sleeve body 18a and a flange portion 18b. The sleeve body 18a has a stepped cylindrical shape. The inner diameter of the upper part of the sleeve body 18a is larger than the outer diameter of the lower part. The flange portion 18b has an annular plate shape. The inner periphery of the flange portion 18b is connected to the upper end of the sleeve body 18a. The sleeve body 18a is disposed in the valve chamber 12. The flange portion 18b contacts the retaining surface 11d.

[0048] The valve core support plate 19 is made of synthetic resin or metal. The valve core support plate 19 has an annular shape. The outer periphery of the valve core support plate 19 is circular, and the inner periphery is elliptical. The valve core support plate 19 is disposed at the lower part of the mounting hole 17. The lower surface of the valve core support plate 19 contacts the flange portion 18b of the sleeve 18.

[0049] The valve core 20 is made of synthetic resin or metal. The valve core 20 integrally has a shaft portion 21 and a valve portion 22.

[0050] The shaft portion 21 has an elliptical cylindrical shape. The cross-sectional shape of the shaft portion 21 is the same as the inner periphery of the valve core support plate 19. The major axis of the cross-section of the shaft portion 21 is the same as the inner diameter of the lower part of the sleeve body 18a. The shaft portion 21 has a threaded hole 21h and an internal thread 21k. The threaded hole 21h is disposed on the upper end face of the shaft portion 21. The internal thread 21k is disposed on the inner circumferential surface of the threaded hole 21h.

[0051] The shaft portion 21 is disposed inside the sleeve 18 and inside the valve core support plate 19. The shaft portion 21 is supported by the sleeve 18 and the valve core support plate 19 and is able to move in the vertical direction. The rotation of the shaft portion 21 about the axis L is limited by the valve core support plate 19. Furthermore, the shape of the shaft portion 21 and the shape of the valve core support plate 19 are only required to limit the rotation of the shaft portion 21 about the axis L.

[0052] The valve portion 22 has a frustum-shaped cone with a diameter that decreases from top to bottom. The valve portion 22 is coaxially connected to the lower end of the shaft portion 21. The valve portion 22 is disposed within the valve chamber 12 and the valve port 13. The valve portion 22 is vertically opposed to the valve port 13 and the valve seat 14. When the valve portion 22 contacts the valve seat 14, the valve port 13 is closed. When the valve portion 22 moves away from the valve seat 14, the valve port 13 opens, forming a throttling flow path between the valve portion 22 and the valve port 13.

[0053] Rolling bearing 25 is a radial bearing. Rolling bearing 25 can also be a thrust bearing.

[0054] The rotor housing 30 is made of a non-magnetic material. For example, the rotor housing 30 is made of a non-magnetic metal such as stainless steel. In this specification, "non-magnetic material" means a material that does not become magnetized even when placed in a magnetic field (including material that is substantially non-magnetic). The rotor housing 30 may also be made of synthetic resin. The rotor housing 30 has a generally cylindrical shape. The rotor housing 30 integrally comprises a first housing portion 31, a second housing portion 32, and a connecting portion 33.

[0055] The first housing portion 31 has a cylindrical shape. The first housing portion 31 has an external thread 31g. The external thread 31g is disposed on the lower part of the outer peripheral surface of the first housing portion 31. The first housing portion 31 is disposed in the mounting hole 17 of the main body component 11, and the external thread 31g engages with the internal thread 11g. The first housing portion 31 is mounted to the main body component 11 via a threaded structure. An O-ring 34 seals the main body component 11 and the first housing portion 31 within the mounting hole 17. The lower end of the first housing portion 31 contacts the upper surface of the valve core support plate 19. Between the lower end of the first housing portion 31 and the retaining surface 11d of the main body component 11, the flange portion 18b of the retaining sleeve 18 and the valve core support plate 19 are retained.

[0056] The first housing portion 31 has a mounting surface 31h. The mounting surface 31h is an upward-facing annular plane. The mounting surface 31h is disposed on the inner circumferential surface of the first housing portion 31. A rolling bearing 25 is disposed inside the first housing portion 31, and the lower end of the outer wheel of the rolling bearing 25 is in contact with the mounting surface 31h. The rolling bearing 25 is fixed to the first housing portion 31.

[0057] The second housing portion 32 has a cylindrical shape. The inner diameter of the second housing portion 32 is larger than the outer diameter of the first housing portion 31. The connecting portion 33 has an annular plate shape. The inner periphery of the connecting portion 33 is connected to the upper end of the first housing portion 31, and the outer periphery of the connecting portion 33 is connected to the lower end of the second housing portion 32. The first housing portion 31, the second housing portion 32, and the connecting portion 33 are coaxially arranged.

[0058] The rotor 35 has a generally cylindrical shape. The rotor 35 is disposed inside the second housing portion 32 of the rotor housing 30. The rotor 35 integrally has a cylindrical portion 36, a bottom portion 37, and a connecting portion 38.

[0059] The cylindrical portion 36 has multiple magnetic poles (multiple N poles and multiple S poles). The multiple N poles and multiple S poles are arranged alternately at equal angular intervals along the circumferential direction on the inner circumferential surface of the cylindrical portion 36. The multiple N poles and multiple S poles extend in the vertical direction. For example, the cylindrical portion 36 has 5 N poles and 5 S poles. The bottom 37 has an annular plate shape. The outer periphery of the bottom 37 is connected to the lower end of the cylindrical portion 36. The connecting portion 38 has a cylindrical shape. The connecting portion 38 is connected to the inner periphery of the bottom 37 and is coaxially arranged with the bottom 37. The rotor 35 is a magnetic rotor.

[0060] The drive component 50 is made of synthetic resin or metal. The drive component 50 has a generally cylindrical shape. The drive component 50 has an external thread 51k. The external thread 51k is disposed on the outer peripheral surface of the lower part of the drive component 50. The external thread 51k engages with the internal thread 21k of the valve core 20. Alternatively, the drive component 50 may have an internal thread, and the valve core 20 may have an external thread. The internal thread 21k and the external thread 51k form a feed thread mechanism that moves the valve core 20 in the vertical direction. The central portion of the drive component 50 is rotatably supported on the rolling bearing 25. The drive component 50 has a support surface 50a. The support surface 50a is a downward-facing annular plane. The support surface 50a is in contact with the upper end of the inner wheel of the rolling bearing 25. The upper part of the drive component 50 engages with the connecting portion 38. The drive component 50 rotates together with the rotor 35.

[0061] like Figure 6 As shown, the stator unit 8 has an inner housing 60, an outer housing 80, a stator 90, and a control device 100.

[0062] The inner housing 60 is made of a non-magnetic material. For example, the inner housing 60 may be made of a non-magnetic metal such as stainless steel. The inner housing 60 may also be made of synthetic resin. The inner housing 60 integrally comprises a peripheral wall portion 61, a bottom wall portion 62, and an annular portion 63.

[0063] The peripheral wall portion 61 has a cylindrical shape. The peripheral wall portion 61 has a plurality of through holes 61a. The plurality of through holes 61a are disposed on the upper part of the peripheral wall portion 61.

[0064] The bottom wall portion 62 has a circular plate shape. The outer periphery of the bottom wall portion 62 is connected to the lower end (first end) of the peripheral wall portion 61.

[0065] The annular portion 63 has a circular ring plate shape. The inner periphery of the annular portion 63 is connected to the upper end (second end) of the peripheral wall portion 61. The outer periphery of the annular portion 63 is joined to the upper end (one end) of the second housing portion 32 of the rotor housing 30. The annular portion 63 is welded to the rotor housing 30. The annular portion 63 can also be joined to the rotor housing 30 by an adhesive. The peripheral wall portion 61, the bottom wall portion 62, and the annular portion 63 are coaxially arranged.

[0066] The peripheral wall portion 61 and the bottom wall portion 62 are disposed inside the rotor 35. The second housing portion 32 of the rotor housing 30 and the inner housing 60 form the rotor space 65. The rotor 35 is disposed in the rotor space 65. The rotor space 65 is sealed relative to the outside of the electric valve 1. The rotor space 65 is connected to the valve chamber 12 through the gaps between the components of the valve body assembly 5. The refrigerant in the valve chamber 12 is introduced into the rotor space 65.

[0067] The outer casing 80 is made of synthetic resin. The outer casing 80 has an outer casing body 81 and a cover 85.

[0068] The outer shell body 81 integrally comprises a wall portion 82, a base portion 83, a support portion 84, and a ring portion 89.

[0069] The wall portion 82 has a cylindrical shape. The outer diameter of the wall portion 82 is larger than the outer diameter of the second housing portion 32 of the rotor housing 30.

[0070] The base 83 has a circular plate shape. The base 83 is connected to the lower end of the wall portion 82. The base 83 is coaxially disposed with the annular portion 63 of the inner housing 60, and the lower surface 83a (one side) of the base 83 is in contact with the upper surface of the annular portion 63. The diameter of the lower surface 83a is smaller than the outer diameter of the annular portion 63, and the outer periphery of the annular portion 63 extends radially outward compared to the lower part of the base 83.

[0071] The support portion 84 has a cylindrical shape. The support portion 84 is connected to the lower surface 83a of the base portion 83. The outer diameter of the support portion 84 is the same as the inner diameter of the peripheral wall portion 61 of the inner housing 60. A plurality of protrusions 84a are provided on the outer peripheral surface of the support portion 84. The support portion 84 is disposed on the inner side of the peripheral wall portion 61, and the protrusions 84a are disposed in the through holes 61a of the peripheral wall portion 61.

[0072] The ring portion 89 has a circular shape. The inner diameter of the ring portion 89 is the same as the outer diameter of the peripheral wall portion 61. The inner peripheral surface of the ring portion 89 contacts the outer peripheral surface of the peripheral wall portion 61 and connects to the protrusion 84a of the support portion 84. The upper end face of the ring portion 89 contacts the lower surface of the annular portion 63. The outer diameter of the ring portion 89 is the same as the inner diameter of the second housing portion 32. The outer peripheral surface of the ring portion 89 contacts the inner peripheral surface of the second housing portion 32, and the ring portion 89 fits into the second housing portion 32. The wall portion 82, the base portion 83, the support portion 84, and the ring portion 89 are arranged coaxially. Furthermore, in the electric valve 1, the ring portion 89 may be omitted.

[0073] The cover 85 integrally comprises a cover portion 86 and a connector portion 87. The cover portion 86 has a circular plate shape. The outer periphery of the cover portion 86 engages with the upper end of the wall portion 82. The connector portion 87 has an elliptical cylindrical shape. The connector portion 87 extends upward from the center of the upper surface of the cover portion 86. The cover portion 86 and the connector portion 87 are coaxially arranged. The wall portion 82, the base portion 83, and the cover portion 86 form a control device space 88.

[0074] The stator 90 has two laminated bodies 91. Each laminated body 91 has a hollow ring-shaped magnetic yoke, a winding frame disposed inside the magnetic yoke, and a coil wound on the winding frame. Multiple claw-shaped pole teeth are provided on the outer periphery of the magnetic yoke. The coil is electrically connected to the coil terminal 94. One laminated body 91 is coaxially disposed on top of the other laminated body 91.

[0075] The stator 90 is embedded in the support portion 84 of the housing 80. The stator 90 and the support portion 84 are disposed together on the inner side of the peripheral wall portion 61 of the inner housing 60. The rotor 35 is disposed on the outer side of the peripheral wall portion 61. The rotor 35 and the stator 90 are radially opposite each other across the peripheral wall portion 61. The rotor 35 and the stator 90 constitute a stepper motor 98. Alternatively, the electric valve 1 may also have other types of motors such as a brushless DC motor.

[0076] The outer shell body 81 is integrally formed with the inner shell 60 and the stator 90. Specifically, the outer shell body 81 is formed by insert molding in which the inner shell 60 and the stator 90 are placed in a mold and synthetic resin is filled into the mold.

[0077] The manufacturing method of the outer shell body 81 will be described.

[0078] (Method 1) The outer shell body 81 is formed by injection molding. An injection mold with a cavity having a shape corresponding to the outer shell body 81 is used. After the inner shell 60 is placed in the cavity of the injection mold, the stator 90 is placed inside the peripheral wall portion 61 of the inner shell 60. Alternatively, the inner shell 60 may be placed inside the peripheral wall portion 61 of the inner shell 60 before being placed in the cavity of the injection mold. Then, molten synthetic resin is injected into the cavity of the injection mold. When the synthetic resin solidifies, the outer shell body 81, which is integrated with the inner shell 60 and the stator 90, is completed.

[0079] (Method 2) The outer shell body 81 is formed by casting. A casting mold with a cavity corresponding to the shape of the outer shell body 81 is used. The casting mold is, for example, cup-shaped. After the inner shell 60 is placed in the cavity of the casting mold, the stator 90 is placed inside the peripheral wall 61 of the inner shell 60. Alternatively, the inner shell 60 may be placed in the cavity of the casting mold after the stator 90 is placed inside the peripheral wall 61 of the inner shell 60. Then, molten synthetic resin is injected into the cavity of the casting mold. When the synthetic resin solidifies, the outer shell body 81, which is integrated with the inner shell 60 and the stator 90, is completed.

[0080] A control device 100 is disposed in a control device space 88. The control device 100 includes a substrate 101, a terminal component 102, and a computer (not shown). The substrate 101 is a printed circuit board on which electronic components, including the computer, are mounted. Multiple coil terminals 94 of the stator 90 are connected to the substrate 101. The terminal component 102 has multiple connector terminals 103. One end of each connector terminal 103 is connected to the substrate 101, and the other end is disposed inside a connector portion 87. The computer controls the electric valve 1.

[0081] In the electric valve 1, the central axis of each of the main components 11 (valve chamber 12, valve port 13, valve seat 14, mounting hole 17), sleeve 18, valve core support plate 19, valve core 20, rolling bearing 25, rotor housing 30, rotor 35, drive component 50, inner housing 60, outer housing 81, cover 85, and stator 90 is aligned with axis L.

[0082] Next, the operation of electric valve 1 will be explained.

[0083] In the electric valve 1, current is supplied to multiple coils of the stator 90, causing the rotor 35 to rotate in a first direction. The drive component 50 rotates together with the rotor 35. Through the interaction between the external thread 51k of the drive component 50 and the feed thread of the internal thread 21k of the valve core 20, the valve core 20 moves downward, and the opening area of ​​the valve port 13 (throttling flow path) decreases. When the valve core 20 contacts the valve seat 14 and the valve port 13 is closed, the electric valve 1 is in a fully closed state.

[0084] In the electric valve 1, current is supplied to multiple coils of the stator 90, causing the rotor 35 to rotate in the second direction. The drive component 50 rotates together with the rotor 35. Through the interaction between the external thread 51k of the drive component 50 and the feed thread of the internal thread 21k of the valve core 20, the valve core 20 moves upward, moving away from the valve seat 14, and the opening area of ​​the valve port 13 increases. When the valve core 20 is furthest away from the valve port 13, the electric valve 1 is in the fully open state. When the electric valve 1 is in the fully open state, the opening area of ​​the valve port 13 is at its maximum.

[0085] Furthermore, the outer shell body 81 of the stator unit 8's outer shell 80 is integrally formed with the inner shell 60 and the stator 90. In particular, the protrusion 84a of the support portion 84 is disposed in the through hole 61a of the peripheral wall portion 61 of the inner shell 60, and the ring portion 89 is connected to the protrusion 84a. Thus, the support portion 84 and the ring portion 89 are firmly combined with the inner shell 60.

[0086] As described above, the electric valve 1 has a valve body assembly 5 and a stator unit 8. The valve body assembly 5 has a cylindrical rotor housing 30 mounted on the valve body 10 and a cylindrical rotor 35 disposed inside the rotor housing 30. The stator unit 8 has a synthetic resin outer shell 80, a metal inner shell 60, and a stator 90. The inner shell 60 has a cylindrical peripheral wall portion 61, a circular plate-shaped bottom wall portion 62 connected to the lower end of the peripheral wall portion 61, and an annular portion 63 whose inner periphery is connected to the upper end of the peripheral wall portion 61. The outer periphery of the annular portion 63 is engaged with the upper end of the rotor housing 30. The peripheral wall portion 61 and the bottom wall portion 62 are disposed inside the rotor 35. The outer shell 80 has a cylindrical support portion 84 disposed inside the peripheral wall portion 61. The stator 90 is embedded in the support portion 84. The support portion 84 is integrally formed with the stator 90 and the inner shell 60.

[0087] Therefore, since the stator 90 is arranged inside the rotor 35, the electric valve 1 can be reduced in size. Furthermore, the support portion 84 is firmly connected to the inner housing 60, which is joined to the rotor housing 30, preventing the support portion 84 from detaching from the inner housing 60. Thus, the electric valve 1 can be reduced in size, and the possibility of the stator unit 8 detaching from the valve body assembly 5 can be prevented.

[0088] Furthermore, the peripheral wall portion 61 has a through hole 61a. A protrusion 84a disposed in the through hole 61a is provided on the outer peripheral surface of the support portion 84. As a result, the support portion 84 is more firmly connected to the inner housing 60, and the possibility of the stator unit 8 falling off the valve body assembly 5 can be more effectively suppressed. Alternatively, in the electric valve 1, the through hole 61a and the protrusion 84a may be omitted.

[0089] Additionally, the outer casing 80 has an annular portion 89 disposed on the outer side of the peripheral wall portion 61. The annular portion 89 is connected to the protrusion 84a of the support portion 84. In this way, the support portion 84 and the inner casing 60 are further firmly connected, which can further effectively prevent the stator unit 8 from falling off the valve body assembly 5. Alternatively, the annular portion 63 of the inner casing 60 may have a through hole, and the lower surface 83a of the base portion 83 of the outer casing 80 may have a protrusion disposed in the through hole, with the annular portion 89 connected to the protrusion.

[0090] Furthermore, the outer diameter of the ring portion 89 is the same as the inner diameter of the second housing portion 32 of the rotor housing 30. The outer peripheral surface of the ring portion 89 is in contact with the inner peripheral surface of the second housing portion 32. Thus, when the ring portion 89 is inserted into the second housing portion 32, the outer shell 80 and the inner shell 60 can be correctly positioned relative to the rotor housing 30.

[0091] Furthermore, the outer casing 80 has a circular plate-shaped base 83. A support portion 84 is connected to the lower surface 83a of the base 83. The lower surface 83a is in contact with the annular portion 63 of the inner casing 60. The diameter of the lower surface 83a is smaller than the outer diameter of the annular portion 63. Therefore, the outer periphery of the annular portion 63 extends radially outward compared to the lower part of the base 83. Thus, it is possible to prevent the base 83 from melting due to heat when the annular portion 63 is welded to the rotor casing 30.

[0092] The stator unit 8 described above has a structure in which the peripheral wall portion 61 of the inner housing 60 has a through hole 61a and the support portion 84 of the outer housing 80 has a protrusion 84a disposed in the through hole 61a. However, the present invention is not limited to this structure. For example, the electric valve 1 can also replace the stator unit 8 and have Figure 7 The stator unit 8B shown is or Figure 8 The stator unit 8C is shown.

[0093] Figure 7 The stator unit 8B shown replaces the through hole 61a and the protrusion 84a by providing a hemispherical recess 61b on the inner peripheral surface of the peripheral wall portion 61, and a hemispherical protrusion 84b disposed on the recess 61b on the outer peripheral surface of the support portion 84. For example, the peripheral wall portion 61 has four recesses 61b, and the support portion 84 has four protrusions 84b. The stator unit 8B does not have a ring portion 89. The stator unit 8B may also have a hemispherical recess on the outer peripheral surface of the support portion 84, and a hemispherical protrusion disposed on the inner peripheral surface of the peripheral wall portion 61.

[0094] or, Figure 8 The stator unit 8C shown replaces the through hole 61a and the protrusion 84a by providing a circumferentially extending annular groove 61c on the inner circumferential surface of the peripheral wall portion 61, and a circumferentially extending annular ridge 84c disposed in the groove 61c on the outer circumferential surface of the support portion 84. For example, the peripheral wall portion 61 has two grooves 61c, and the support portion 84 has two ridges 84c. The stator unit 8C does not have an annular portion 89. The stator unit 8C may also have a circumferentially extending annular groove on the outer circumferential surface of the support portion 84, and a circumferentially extending annular ridge disposed in the groove on the inner circumferential surface of the peripheral wall portion 61.

[0095] In these stator units 8B and 8C, the outer shell body 81 is also integrally formed with the inner shell 60 and the stator 90, and the support part 84 is more firmly connected with the inner shell 60.

[0096] (Second Embodiment)

[0097] Next, refer to Figure 9 The valve device according to the second embodiment of the present invention will be described.

[0098] like Figure 9 As shown, the valve device 2 in the second embodiment includes the electric valve 1 and flow path block 550 in the first embodiment.

[0099] The flow path block 550 has a cuboid shape. The flow path block 550 is made of metal such as aluminum alloy. The upper surface of the flow path block 550 is the mounting surface 551 for mounting the electric valve 1.

[0100] The flow path block 550 has a first passage 555, a second passage 556, and a mounting hole 557. The mounting hole 557 is disposed on the mounting surface 551. The first passage 555 extends forward from the mounting hole 557. The second passage 556 extends downward from the mounting hole 557.

[0101] The flow path block 550 has an internal thread 550f. The internal thread 550f is disposed on the inner circumferential surface of the mounting hole 557. The main body component 11 of the electric valve 1 is disposed in the mounting hole 557, and the external thread 11f of the main body component 11 engages with the internal thread 550f. The manufacturing tool of the electric valve 1 is mounted on the head 11a of the main body component 11 and is mounted to the flow path block 550 by rotating about the axis L via a threaded structure. The connector portion 87 of the electric valve 1 faces upward. In the mounting hole 557, the main body component 11 and the flow path block 550 are sealed by O-rings 558 and 559. The first passage 555 is connected to the valve chamber 12 of the electric valve 1 via the mounting hole 557 and the first connecting passage 15. The second passage 556 is connected to the valve port 13 of the electric valve 1 via the second connecting passage 16.

[0102] Alternatively, the valve device 2 may have the following structure: the electric valve 1 does not have a main body component 11, and the rotor housing 30 of the electric valve 1 is directly mounted on the flow path block 550. In this structure, the flow path block 550 has a valve chamber, valve port, valve seat, and mounting hole that are the same as (or substantially the same as) those of the electric valve 1.

[0103] Alternatively, the valve device 2 may have the following structure: it has multiple mounting holes 557 for arranging the flow path block 550 on the mounting surface 551, and an electric valve 1 is arranged in each mounting hole 557. In this structure, the connector portions 87 of the multiple electric valves 1 face the same direction (upward). Therefore, in a system equipped with the valve device 2 of this structure, only space needs to be provided above the valve device 2 for arranging cables connected to the connector portions 87 of the multiple electric valves 1, allowing the valve device 2 to be arranged in a relatively small space.

[0104] In valve device 2, it also has the same effect as electric valve 1.

[0105] In this specification, the terms "cylinder," "cylindrical," "cuboid," etc., are also used for parts or portions of parts that substantially have the shape described by that term. For example, "cylindrical-shaped part" includes both cylindrical-shaped parts and parts that are substantially cylindrical.

[0106] The embodiments of the present invention have been described above, but the present invention is not limited to the structure of the embodiments. Embodiments in which elements are added, deleted, or designed in a suitable manner, or embodiments in which features are appropriately combined, are appropriate for those skilled in the art, and are also included within the scope of the present invention, provided they do not depart from its spirit.

[0107] Symbol Explanation

[0108] 1… Electric valve, 5… Valve body assembly, 10… Valve body, 11… Main body component, 20… Valve core, 25… Rolling bearing, 30… Rotor housing, 35… Rotor, 50… Drive component, 8, 8B, 8C… Stator unit, 60… Inner housing, 61… Peripheral wall, 61a… Through hole, 61b… Recess, 61c… Groove, 62… Bottom wall, 63… Annular part, 80… Outer shell, 81… Outer shell body, 82… Wall, 83… Base, 83a… Lower surface, 84… Support part, 84a… Protrusion, 84b… Protrusion, 84c… Raised strip, 85… Cover, 86… Cover, 87… Connector part, 89… Ring, 90… Stator, 98… Stepper motor, 100… Control device, 2… Valve device, 550… Flow path block.

Claims

1. An electric valve comprising a valve body assembly and a stator unit, characterized in that, The valve body assembly has a cylindrical rotor housing mounted on the valve body and a cylindrical magnetic rotor disposed inside the rotor housing. The stator unit has a synthetic resin outer shell, a metal inner shell, and a stator. The inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion whose inner periphery is connected to a second end of the peripheral wall portion. The outer periphery of the annular portion is joined to one end of the rotor housing. The peripheral wall portion and the bottom wall portion are disposed on the inner side of the magnetic rotor. The outer casing has a cylindrical support portion disposed on the inner side of the peripheral wall portion. The stator is embedded in the support portion. The support portion is integrally formed with the stator and the inner housing.

2. The electric valve according to claim 1, characterized in that, The peripheral wall portion has a through hole, and a protrusion disposed in the through hole is provided on the outer peripheral surface of the support portion.

3. The electric valve according to claim 2, characterized in that, The outer casing also has a ring portion disposed on the outer side of the peripheral wall portion. The ring portion is connected to the protrusion portion.

4. The electric valve according to claim 3, characterized in that, The outer diameter of the ring is the same as the inner diameter of the rotor housing. The outer circumferential surface of the ring is in contact with the inner circumferential surface of the rotor housing.

5. The electric valve according to claim 1, characterized in that, A recess is provided on the inner peripheral surface of the peripheral wall portion and a protrusion disposed in the recess is provided on the outer peripheral surface of the support portion; or, a recess is provided on the outer peripheral surface of the support portion and a protrusion disposed in the recess is provided on the inner peripheral surface of the peripheral wall portion.

6. The electric valve according to claim 1, characterized in that, The outer shell also has a circular plate-shaped base. The support portion is connected to one side of the base portion. The surface is in contact with the annular portion, and the diameter of the surface is smaller than the outer diameter of the annular portion.

7. A valve device, characterized in that, have: The electric valve according to any one of claims 1 to 6; and a flow path block having a mounting surface for configuring the electric valve.

8. A method for manufacturing a stator unit, the stator unit comprising a synthetic resin outer shell, a metal inner shell, and a stator, characterized in that, The inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion whose inner periphery is connected to a second end of the peripheral wall portion. The outer casing has an outer casing body, which has a cylindrical support portion disposed on the inner side of the peripheral wall portion. The stator is disposed on the inner side of the peripheral wall portion, and the inner housing is disposed in the cavity of the injection mold. The outer shell body is formed by injecting synthetic resin into the cavity.

9. A method for manufacturing a stator unit, the stator unit comprising a synthetic resin outer shell, a metal inner shell, and a stator, characterized in that, The inner shell has a cylindrical peripheral wall portion, a circular plate-shaped bottom wall portion connected to a first end of the peripheral wall portion, and an annular portion whose inner periphery is connected to a second end of the peripheral wall portion. The outer casing has an outer casing body, which has a cylindrical support portion disposed on the inner side of the peripheral wall portion. The stator is disposed on the inner side of the peripheral wall portion, and the inner housing is disposed in the cavity of the casting mold. The outer shell body is formed by injecting synthetic resin into the cavity.

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