Motorised valve

Abstract

Provided is an electric valve capable of suppressing breakage of a cover of a stator unit. An electric valve (1) has a valve main body (10), a housing (20), and a stator unit (30). The stator unit (30) has an opening (30a) into which the housing 20 is inserted in the axial direction. A cover (40) of the stator unit (30) has a dome portion (43) inside which a ceiling portion (22) of the housing (20) is arranged. An inner surface of the dome portion (43) has a corner portion (46) extending linearly. The housing (20) is held to the stator unit (30) at a mounting position at which the ceiling portion (22) and the dome portion (43) are spaced apart in the axial direction. The housing (20) is movable toward the mounting position at a contact position at which the ceiling portion (22) and the corner portion (46) of the dome portion (43) are in contact in the axial direction.

Description

Technical Field

[0001] This invention relates to an electric valve. Background Technology

[0002] An example of a conventional electric valve is disclosed in Patent Document 1.

[0003] Patent Document 1 discloses an electric valve comprising an electric valve body and a stator unit (coil for the electric valve). The electric valve body has a metal housing. The stator unit comprises a cover and a stator. The cover is made of synthetic resin and has a cap shape. The stator has a cylindrical shape and is disposed within the cover. A filling resin is filled between the cover and the stator. The stator unit has an opening for inserting the electric valve body. The cover has a domed top. A hemispherical canopy portion of the electric valve body is disposed inside the domed top.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2001-343085

[0007] The technical problem that the invention aims to solve

[0008] The aforementioned electric valve is used in devices such as outdoor units of air conditioners. During operation, vibrations are transmitted to the electric valve. The stator unit of the electric valve is mounted to the valve body via a resilient retaining plate. Therefore, due to vibrations, the top portion of the housing repeatedly collides with the dome within the stator unit, potentially causing damage to the dome. Furthermore, during assembly, the valve body is inserted into the opening of the stator unit. However, if the valve body continues to be inserted into this opening, the top of the top portion impacts the dome, concentrating the force of insertion at a single point, which could potentially cause damage to the dome. Summary of the Invention

[0009] Therefore, the object of the present invention is to provide an electric valve capable of suppressing damage to the stator unit cover.

[0010] To achieve the above objectives, one embodiment of the electric valve of the present invention includes a valve body, a housing mounted on the valve body, and a stator unit mounted on the outside of the housing. The housing has a cylindrical portion and a canopy portion connected to one end of the cylindrical portion. The stator unit has a cap-shaped cover, a cylindrical stator disposed inside the cover, and a molded part made of a filling resin filled between the stator and the cover. The stator unit has an opening for the housing to be inserted axially. The cover has a dome, and the canopy portion is disposed inside the dome. At a mounting position in which the canopy portion and the dome are axially spaced apart, the housing is held in the stator unit. At a contact position in which the canopy portion and the dome contact each other axially, the housing is movable toward the mounting position.

[0011] According to the present invention, at the contact position where the top portion and the dome are in axial contact, the housing can move toward the mounting position, and the housing is not held in the stator unit. Furthermore, at the mounting position where the top portion and the dome are axially spaced apart, the housing is held in the stator unit. In this way, when in the mounting position, the housing is held in the stator unit, thereby preventing repeated collisions between the dome and the top portion of the housing even when vibrations are transmitted to the electric valve. Therefore, damage to the stator unit cover can be suppressed.

[0012] When the housing is inserted into the opening until the mounting position, the dome is configured to be axially spaced opposite the canopy portion. When the housing is inserted into the opening to a depth greater than the mounting position, the housing is positioned at the contact position. Therefore, by preventing the housing from being inserted at the mounting position, contact between the canopy portion and the dome can be avoided.

[0013] In this invention, it is preferable that the inner surface of the dome has a corner portion, which is positioned opposite the top portion in the axial direction with a gap when the housing is disposed in the mounting position, and makes line contact with the top portion when the housing is disposed in the contact position. In this way, when the housing is disposed in a contact position deeper than the mounting position, the top portion of the housing makes line contact with the corner portion of the cover, preventing the force of housing insertion from concentrating at a single point. Therefore, damage to the stator unit cover can be suppressed.

[0014] In this invention, it is preferable that the corner portion is coaxially configured with the housing and has a circular or arcuate shape, the circular or arcuate shape having a diameter smaller than the outer diameter of the housing. In this way, when the roof portion impacts the corner portion, the rounded top can be subjected to force more evenly. Therefore, damage to the cover can be more effectively suppressed.

[0015] In the present invention, preferably, the cylindrical portion of the housing has a plurality of hemispherical protrusions, the stator unit has a plurality of holding pieces disposed opposite to the outer peripheral surface of the cylindrical portion, the plurality of holding pieces have holding portions, and the holding portions are formed by through holes or recesses that hold the protrusions when the housing is disposed at the mounting position. The size of the holding portion in the axial direction is not greater than the diameter of the protrusion. When the length in the axial direction from the center of the holding portion to the corner portion is set as L1, the length in the axial direction from the center of the protrusion to the portion in the ceiling portion that contacts the corner portion is set as L2, and the size of the holding portion in the axial direction is set as D1, the electric valve satisfies "L1 - L2 < D1 / 2". By doing so, in a state where the ceiling portion contacts the corner portion, the center of the protrusion is positioned within the holding portion and at a portion of the holding portion closer to the dome portion than the axial center. At this time, the holding piece elastically deforms, and by the restoring force of the holding piece, the housing moves to a position (mounting position) where the center of the protrusion coincides with the axial center of the holding portion. Therefore, the housing can be correctly positioned relative to the stator unit.

[0016] In the present invention, preferably, the thickness of the top of the dome portion is smaller than the thickness from the outer surface of the dome portion to the corner portion. By doing so, the thickness of the dome portion can be made thinner, and shrinkage of the resin that may occur during the molding of the cover can be suppressed.

[0017] In the present invention, preferably, the dome portion has ribs extending on the inner surface of the dome portion. When the housing is disposed at the mounting position, the ribs are opposed to the ceiling portion with a space in the axial direction. When the housing is disposed at the contact position, the top surface of the rib is in surface contact with the ceiling portion. By doing so, when the housing is disposed at a contact position deeper than the mounting position, the ceiling portion of the housing is in surface contact with the rib of the cover, and the force for inserting the housing can be prevented from concentrating at one point. Therefore, breakage of the cover of the stator unit can be suppressed.

[0018] In the present invention, preferably, the ribs are disposed coaxially with the housing and have a circular shape or an arc shape, and the circular shape or the arc shape has a diameter smaller than the outer diameter of the housing. By doing so, when the ceiling portion impacts the rib, the dome portion can be more evenly stressed. Therefore, breakage of the cover can be more effectively suppressed.

[0019] In the present invention, preferably, the cylindrical portion of the housing has a plurality of hemispherical protrusions, the stator unit has a plurality of holding pieces disposed opposite to the outer peripheral surface of the cylindrical portion, the plurality of holding pieces have holding portions formed by through holes or recesses that hold the protrusions when the housing is disposed at the mounting position, the size of the holding portions in the axial direction is not greater than the diameter of the protrusions, when the length in the axial direction from the center of the holding portion to the rib is set as L3, the length in the axial direction from the center of the protrusion to the portion of the ceiling portion that contacts the rib is set as L4, and the size of the holding portion in the axial direction is set as D1, the electric valve satisfies "L3 - L4 < D1 / 2". By doing so, in a state where the ceiling portion contacts the rib, the center of the protrusion is positioned within the holding portion and closer to the dome portion than the center of the holding portion in the above-mentioned axial direction. At this time, the holding piece elastically deforms, and by the restoring force of the holding piece, the housing moves to a position where the center of the protrusion coincides with the center of the holding portion in the axial direction (mounting position). Thereby, the housing can be correctly positioned relative to the stator unit.

[0020] In the present invention, preferably, the thickness of the top of the dome portion is smaller than the thickness from the outer surface of the dome portion to the top surface of the rib. By doing so, the thickness of the dome portion can be made thinner, and shrinkage of the resin that may occur during the molding of the cover can be suppressed.

[0021] In the present invention, preferably, there is an opening at the top of the dome portion. By doing so, the axial size of the electric valve can be further reduced.

[0022] Advantages of the Invention

[0023] According to the present invention, breakage of the cover of the stator unit can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 FIG. is a view showing an electric valve according to an embodiment of the present invention.

[0025] Figure 2 is Figure 1 a bottom view of a cover of a stator unit included in the electric valve.

[0026] Figure 3 is a perspective view including a Figure 2 partial cross-section of the cover.

[0027] Figure 4 is Figure 1 a cross-sectional view of a stator of a stator unit included in the electric valve.

[0028] Figure 5 is Figure 1 an enlarged view of the electric valve.

[0029] Figure 6 yes Figure 1 Another enlarged view of the electric valve.

[0030] Figure 7 It means Figure 1 A diagram showing the structure of a modified electric valve.

[0031] Figure 8 yes Figure 7 A bottom view of the stator unit housing of the electric valve.

[0032] Figure 9 It includes Figure 8 A three-dimensional view of a partial cross-section of the cover.

[0033] Figure 10 yes Figure 7 An enlarged cross-sectional view of the electric valve.

[0034] Figure 11 It means Figure 1 A diagram showing the structure of another variation of the electric valve.

[0035] Figure 12 This is a diagram showing an existing electric valve.

[0036] Symbol Explanation

[0037] 1, 1A, 1B… Electric valve, 10… Valve body, 11… First conduit, 12… Second conduit, 20… Housing, 21… Cylindrical section, 22… Top section, 23… Protrusion, 30… Stator unit, 40, 40A, 40B… Cover, 41… Peripheral wall section, 42… Upper end wall section, 43… Dome, 46… Corner, 46a… Annular plane, 46b… Circumferential surface, 48… Rib, 48a… Top surface, 49… Opening, 50… Stator, 51 …First stator, 51a…magnetic yoke, 51b…winding frame, 51c…coil, 51d…pole tooth, 52…second stator, 52a…magnetic yoke, 52b…winding frame, 52c…coil, 52d…pole tooth, 53…fixed component, 54…plate section, 54a…through hole, 55…connecting piece, 56…holding piece, 56a…holding part, 57…lead connection part, 58…coil terminal pin, 59…lead, 60…molded part, L…axis. Detailed Implementation

[0038] The following is for reference Figures 1-6 An electric valve according to an embodiment of the present invention will be described.

[0039] Figure 1 This is a front view of an electric valve representing an embodiment of the present invention. Figure 2 yes Figure 1 A bottom view of the stator unit housing of the electric valve. Figure 3 It includes Figure 2 A three-dimensional view of a partial cross-section of the cover. Figure 4 yes Figure 1 A cross-sectional view of the stator unit of the electric valve. Figure 5 , Figure 6 yes Figure 1 An enlarged front view of the electric valve. Figure 5 This indicates the state in which the housing is inserted into the opening of the stator unit until it reaches the installation position. Figure 6 This indicates the state where the housing is further inserted into the stator unit from its mounting position. Figure 1 , Figure 5 , Figure 6 In the diagram, the stator unit is represented by a sectional view.

[0040] like Figure 1 As shown, the electric valve 1 has a valve body 10, a housing 20, and a stator unit 30. Furthermore, in the following description, "up and down" indicates the positional relationship in the figures.

[0041] The valve body 10 has a bottomed cylindrical shape. The valve body 10 has a valve chamber (not shown) and a valve port (not shown) opening in the valve chamber. A first conduit 11 and a second conduit 12 are brazed to the valve body 10. The first conduit 11 is connected to the valve chamber. The second conduit 12 is connected to the valve port. A valve core (not shown) for opening and closing the valve port is disposed in the valve chamber.

[0042] The housing 20 has a cylindrical shape with its upper end closed. The housing 20 integrally comprises a cylindrical portion 21 and a top portion 22. A valve body 10 is mounted at the lower end of the cylindrical portion 21. Multiple protrusions 23 are arranged on the outer peripheral surface of the cylindrical portion 21. Each protrusion 23 has a hemispherical shape. Furthermore, "hemispherical shape" in this specification includes a shape where a sphere is precisely cut in half, and a roughly hemispherical shape such as a dome shape where a sphere is cut with a plane (excluding the center of the sphere). Four protrusions 23 are arranged at 90-degree intervals on the outer peripheral surface of the cylindrical portion 21. The top portion 22 has a hemispherical shape. The top portion 22 is connected to the upper end (one end) of the cylindrical portion 21. The top portion 22 closes the upper end of the cylindrical portion 21. A rotor (not shown) is arranged inside the housing 20. The rotor, together with the stator unit 30, constitutes a stepper motor. The valve body 10 is made of stainless steel or brass. The housing 20 is made of stainless steel.

[0043] The stator unit 30 is disposed on the outside of the housing 20. The stator unit 30 has a cover 40, a stator 50, and a molded part 60.

[0044] The cover 40 is made of synthetic resin. The cover 40 is manufactured by injection molding. The cover 40 has a cap shape. The cover 40 integrally has a peripheral wall portion 41 and an upper end wall portion 42. When a stator 50 is disposed inside the peripheral wall portion 41, there is a space between the peripheral wall portion 41 and the stator 50. The upper end wall portion 42 is connected to the upper end 41a (one end) of the peripheral wall portion 41. A dome 43 protruding upwards is formed in the upper end wall portion 42 at a location opposite to the housing 20. The inner diameter of the dome 43 is the same as the outer diameter of the housing 20.

[0045] like Figure 2 , Figure 3 As shown, the inner surface of the dome 43 has a linearly extending corner 46. The corner 46 is formed by a downward-facing annular plane 46a and an inward-facing circumferential surface 46b connected to the inner periphery of the annular plane 46a. The annular plane 46a and the circumferential surface 46b are perpendicular. The corner 46 has a circular shape and is coaxially arranged with the housing 20. The diameter of the corner 46 is smaller than the outer diameter of the housing 20. Alternatively, the corner 46 may also have multiple arc shapes formed by partially cutting an ellipse or a circle. The thickness of the top of the dome 43 is smaller than the thickness from the outer surface of the dome 43 to the corner 46.

[0046] Cover 40, for example, is made of polybutylene terephthalate (PBT), with a linear expansion coefficient of 2.5 × 10⁻⁶. -5 / ℃), polyphenylene oxide (PPE, coefficient of linear expansion 6.6×10 -5 It is composed of hard resins such as ( / ℃).

[0047] The stator 50 has a cylindrical shape. The stator 50 has a first stator 51, a second stator 52, a fixing member 53, and a lead wire connection part 57. The first stator 51, the second stator 52, and the fixing member 53 are arranged in the vertical direction (axis L direction).

[0048] The first stator 51 has a magnetic yoke 51a, a winding frame 51b, and a coil 51c. The magnetic yoke 51a is a metal part. The coil wire constituting the coil 51c is wound on the magnetic yoke 51a via the winding frame 51b. The magnetic yoke 51a has a plurality of claw-shaped pole teeth 51d. The plurality of pole teeth 51d have downward-facing pole teeth with their tips (the thinner end) pointing downwards and upward-facing pole teeth with their tips pointing upwards. The downward-facing pole teeth and the upward-facing pole teeth are arranged alternately in the circumferential direction.

[0049] Similar to the first stator 51, the second stator 52 has a magnetic yoke 52a, a winding frame 52b, a coil 52c, and a plurality of pole teeth 52d, all of which are metal parts. The inner diameters of the first stator 51 and the second stator 52 are the same as the outer diameter of the housing 20.

[0050] The fixing member 53 has an annular flat plate portion 54, multiple connecting pieces 55, and multiple retaining pieces 56. The fixing member 53 is formed by stamping a metal plate into the shape of the flat plate portion 54, the multiple connecting pieces 55, and the multiple retaining pieces 56. The multiple connecting pieces 55 are bent in one direction to form a right angle with respect to the flat plate portion 54, and the multiple retaining pieces 56 are bent in another direction to form a right angle with respect to the flat plate portion 54. The flat plate portion 54 has multiple through holes 54a. The multiple connecting pieces 55 are welded to the yoke 52a of the second stator 52. The first stator 51, the second stator 52, and the fixing member 53 are coaxially arranged.

[0051] In this embodiment, the fixing member 53 has four retaining pieces 56. Each retaining piece 56 is configured corresponding to a plurality of protrusions 23 of the housing 20. The plurality of retaining pieces 56 are configured opposite to the cylindrical portion 21 of the housing 20 in the transverse direction (orthogonal to the axis L). The plurality of retaining pieces 56 are elastically deformable. The plurality of retaining pieces 56 have retaining portions 56a formed by through holes. The vertical dimension D1 of the retaining portion 56a is less than or equal to the diameter D2 of the protrusions 23 of the housing 20. When the housing 20 is in the mounting position ( Figure 1 , Figure 5 When the protrusion 23 is centered, the center of the retaining portion 56a in the vertical direction overlaps with the center of the retaining portion 23, and the retaining portion 56a retains the protrusion 23. Thus, the positions of the housing 20 and the stator unit 30 are fixed. That is, the mounting position is the position where the housing 20 is fixed to the stator unit 30. When the housing 20 is in the mounting position, the housing 20 and the stator unit 30 are correctly mounted. Alternatively, instead of a through hole, the retaining portion 56a can also be a recess that follows the shape of the protrusion 23.

[0052] The lead connection portion 57 is a substrate connected to the top end of the coil terminal pin 58 extending from the stator 50 in a direction orthogonal to the axis L. The lead 59 is connected to the lead connection portion 57.

[0053] In this embodiment, the inner diameter of the stator 50 (specifically, the inner diameters of the first stator 51 and the second stator 52) is the same as the inner diameter of the dome 43 of the cover 40.

[0054] The stator 50 is disposed inside the cover 40. The first stator 51 of the stator 50 is in contact with the upper end wall 42.

[0055] The molded part 60 fills the interior of the stator 50 (specifically, the interior of the first stator 51, the interior of the second stator 52, the space between the second stator 52 and the plate portion 54, and the plurality of through holes 54a in the plate portion 54). The plate portion 54 is embedded in the molded part 60. In addition, the molded part 60 also fills the space between the cover 40 and the stator 50.

[0056] The molded part 60 is made of, for example, a highly flexible resin such as polyurethane, epoxy resin, or silicone (hereinafter referred to as "filler resin"). In this embodiment, thermosetting polyurethane is used as the filler resin.

[0057] The stator unit 30 has an opening 30a. The opening 30a is connected to the inner space of the stator 50. The housing 20 is inserted into the opening 30a along the axis L. The cylindrical portion 21 of the housing 20 is disposed inside the stator 50, and the top portion 22 of the housing 20 is disposed inside the dome 43. Inside the dome 43, the top portion 22 and the corner portion 46 are disposed with a gap in the axis L.

[0058] In the electric valve 1, the central axis of each of the valve body 10, housing 20, and stator unit 30 (opening 30a, dome 43, corner 46, stator 50) is aligned with axis L.

[0059] Next, an example of the assembly method of electric valve 1 will be described.

[0060] The first conduit 11 and the second conduit 12 are brazed to the valve body 10. The valve body, rotor and other parts (not shown) are assembled into the housing 20, and the lower end of the housing 20 is welded to the upper end of the valve body 10.

[0061] With the lower end 41b of the cover 40 facing upwards, the stator 50 is positioned inside the cover 40. A cylindrical clamp (not shown) with an outer diameter identical to that of the housing 20 is inserted into the stator 50 and the dome 43 of the cover 40. This positions the cover 40 and the stator 50. Then, polyurethane, as a liquid filling resin, is injected into the cover 40, filling the interior of the stator 50 and the space between the cover 40 and the stator 50. The polyurethane hardens to form a molded part 60. The clamp is then removed from the stator 50 and the dome 43 of the cover 40. The portion containing the clamp becomes the opening 30a of the stator unit 30.

[0062] Then, the holding portions 56a of the plurality of holding plates 56 and the plurality of protrusions 23 of the housing 20 are arranged in the direction of the axis L. The housing 20 is inserted into the opening 30a of the stator unit 30 along the direction of the axis L. Figure 5 As shown, when the housing 20 is inserted into the opening 30a until the designated installation position, the plurality of protrusions 23 of the housing 20 are held in the holding portions 56a of the plurality of holding plates 56. Specifically, the center of the holding portion 56a in the vertical direction coincides with the center of the protrusion 23. Figure 5 The line K1 shown is the line passing through the center of the retaining part 56a in the vertical direction and the center of the protrusion 23. At this time, the corner 46 of the cover 40 is configured to be openly spaced opposite the top part 22 of the housing 20 in the vertical direction. In the installed position, the housing 20 is held in the stator unit 30.

[0063] Additionally, when the force applied to insert the housing 20 into the opening 30a is relatively strong, and the housing 20 is inserted into the opening 30a until it reaches a contact position deeper than the installation position, such as... Figure 6 As shown, the corner portion 46 and the top portion 22 are in line contact in the vertical direction. In the contact position, the housing 20 is not held at the stator unit 30, but can move downward (towards the installation position). Moreover, in the electric valve 1 of this embodiment, when the length in the vertical direction from the center of the holding portion 56a to the corner portion 46 is set to L1, the length in the vertical direction from the center of the protrusion 23 of the housing 20 to the part P1 in the top portion 22 that contacts the corner portion 46 is set to L2, and the size in the vertical direction of the holding portion 56a is set to D1, the following formula (1) is satisfied.

[0064] L1-L2 <D1 / 2…(1)

[0065] Thus, when the canopy portion 22 is in contact with the corner portion 46, the center of the protrusion 23 is positioned within the retaining portion 56a and closer to the dome 43 than the vertical center of the retaining portion 56a. Figure 6 The line K2 shown is the line passing through the center of the protrusion 23. At this time, the retaining plate 56 elastically deforms, and when the operator removes his hand from the housing 20, due to the restoring force of the retaining plate 56, the housing 20 automatically moves to a position (installation position) where the center of the protrusion 23 coincides with the center of the retaining portion 56a in the vertical direction. Thus, the housing 20 can be correctly positioned relative to the stator unit 30.

[0066] Furthermore, the aforementioned method of installing the housing 20 and the stator unit 30 involves arranging the retaining portion 56a and the protrusion 23 in the direction of the axis L, and inserting the housing 20 into the opening 30a of the stator unit 30 along the direction of the axis L. However, the method of installing the housing 20 and the stator unit 30 is not limited to this method. For example, the retaining piece 56 and the protrusion 23 may not be arranged in the direction of the axis L, and the housing 20 may be inserted into the opening 30a of the stator unit 30 along the direction of the axis L, such that the top portion 22 of the housing 20 abuts against the corner portion 46 of the cover 40 (i.e., the housing 20 is positioned in the contact position). With the top portion 22 abutting against the corner portion 46, the housing 20 is rotated relative to the cover 40 (stator unit 30) about the axis L. As a result, the protrusion 23 moves in the rotational direction with the axis L as the axis of rotation, and the center of the protrusion 23 enters the retaining portion 56a. Then, when the operator removes their hand from the housing 20, due to the restoring force of the retaining plate 56, the housing 20 automatically moves to a position (installation position) where the center of the protrusion 23 aligns with the center of the retaining portion 56a in the vertical direction. This installation method can also correctly position the housing 20 relative to the stator unit 30 in the same way as the installation method described above.

[0067] As described above, the electric valve 1 of this embodiment includes: a valve body 10, a housing 20 mounted on the valve body 10, and a stator unit 30 mounted on the outside of the housing 20. The housing 20 has a cylindrical portion 21 and a canopy portion 22 connected to the upper end of the cylindrical portion 21. The stator unit 30 has a cap-shaped cover 40, cylindrical stators (first stator 51 and second stator 52) disposed inside the cover, and a molded part 60 made of filling resin filled between the stator and the cover 40. The stator unit 30 has an opening 30a for the housing 20 to be inserted in the vertical direction (axis L direction). The cover 40 has a dome 43, and the canopy portion 22 is disposed inside the dome 43. In a mounting position where the canopy portion 22 and the dome 43 are spaced apart in the vertical direction, the housing 20 is held in the stator unit 30. Furthermore, at the contact position where the top portion 22 and the dome 43 contact each other in the vertical direction, the housing 20 can move towards the mounting position. In this way, the housing 20 is not held to the stator unit 30 when in the contact position. Moreover, when the housing 20 is held to the stator unit 30 in the mounting position, repeated collisions between the dome 43 and the top portion 22 of the housing 20 are avoided even if vibration is transmitted to the electric valve 1. Therefore, damage to the cover 40 of the stator unit 30 can be suppressed.

[0068] Furthermore, when the housing 20 is inserted into the opening 30a until it reaches the installation position, the dome 43 is configured to be positioned opposite the canopy portion 22 with a vertical gap. When the housing 20 is inserted into the opening 30a to a depth greater than the installation position, the housing 20 is positioned in a contact position. In this way, the installation position is positioned before the contact position in the insertion direction. Therefore, by preventing the housing 20 from being inserted into the installation position, contact between the canopy portion 22 and the dome 43 can be avoided.

[0069] Furthermore, the inner surface of the dome 43 has a corner 46. When the housing 20 is positioned in the mounting position at the opening 30a of the stator unit 30, the corner 46 and the top portion 22 are positioned opposite each other with a gap in the vertical direction. Moreover, when the housing 20 is positioned in a contact position deeper than the mounting position, the corner 46 makes line contact with the top portion 22. In this way, when the housing 20 is positioned in the mounting position, the top portion 22 and the corner 46 are positioned with a gap, and the housing 20 is held in the stator unit 30. Therefore, even if vibration is transmitted to the electric valve 1, repeated collisions between the dome 43 and the top portion 22 of the housing 20 can be avoided. In addition, when the housing 20 is inserted into the housing until it makes a contact position deeper than the mounting position, the top portion 22 of the housing 20 makes line contact with the corner 46 of the cover 40, which can prevent the force of inserting the housing 20 from being concentrated at one point. Therefore, damage to the cover 40 of the stator unit 30 can be avoided.

[0070] In addition, the corner portion 46 is arranged coaxially with the housing 20 and has a circular shape, and the circular shape has a diameter smaller than the outer diameter of the housing 20. By doing so, when the ceiling portion 22 hits the corner portion 46, the dome top 43 can be stressed more evenly. Therefore, it is possible to more effectively suppress the breakage of the cover 40.

[0071] In addition, the cylindrical portion 21 of the housing 20 has a plurality of hemispherical protrusions 23. The stator unit 30 has a plurality of holding pieces 56 arranged opposite to the outer peripheral surface of the cylindrical portion 21. The plurality of holding pieces 56 have a holding portion 56a that holds the protrusion 23 when the housing 20 is arranged at the installation position. The size of the holding portion 56a in the vertical direction is not more than the diameter of the protrusion 23. When the length in the vertical direction from the center of the holding portion 56a in the vertical direction to the corner portion 46 is set as L1, the length in the vertical direction from the center of the protrusion 23 to the portion P1 in the ceiling portion 22 that contacts the corner portion 46 is set as L2, and the size of the holding portion 56a in the vertical direction is set as D1, the electric valve 1 satisfies "L1 - L2 < D1 / 2". By doing so, in the state where the ceiling portion 22 contacts the corner portion 46, the center of the protrusion 23 is positioned within the holding portion 56a and at a portion closer to the dome top 43 than the center of the holding portion 56a in the vertical direction. At this time, the holding piece 56 elastically deforms, and due to the restoring force of the holding piece 56, the housing 20 moves to a position (installation position) where the center of the protrusion 23 coincides with the center of the holding portion 56a in the vertical direction. Thus, the housing 20 can be correctly positioned relative to the stator unit 30. In addition, in the present embodiment, the size of the interval between the ceiling portion 22 and the corner portion 46 of the housing 20 when the housing 20 is at the installation position is such that the ceiling portion 22 and the corner portion 46 do not collide even when the electric valve 1 vibrates, and it is preferably 0.5 to 3 mm.

[0072] In addition, in the electric valve 1, the top of the dome top 43 is closed, but an opening may be provided at the top of the dome top 43. Figure 11 An electric valve 1B having a cover 40B is shown, and the cover 40B has an opening 49 at the top of the dome top 43. The opening 49 is arranged inside the corner portion 46. By doing so, the electric valve 1B can further reduce the size in the vertical direction.

[0073] In addition, the thickness of the top of the dome top 43 is smaller than the thickness from the outer surface of the dome top 43 to the corner portion 46. By doing so, it is possible to suppress the shrinkage of the resin that may occur during the molding of the cover 40. For example, Figure 12 the shown existing electric valve 1C has a cover 40C, and the cover 40C has a dome top 43C with an increased thickness to ensure rigidity. Except for the cover 40C, the electric valve 1C has the same structure as the above-mentioned electric valve 1. In this way, if the thickness of the dome top 43C is large, shrinkage (depression) of the resin occurs during the molding of the cover 40C, which may lead to poor molding.

[0074] In the aforementioned electric valve 1, the cover 40 has a corner portion 46, but the present invention is not limited to this structure. Figures 7-10 In the figure, electric valve 1A is shown as a modified example of the electric valve 1 described above.

[0075] Figure 7 This is a front view showing a modified example of the structure of the electric valve of the present invention. Figure 8 yes Figure 7 A bottom view of the stator unit housing of the electric valve. Figure 9 It includes Figure 8 A three-dimensional view of a partial cross-section of the cover. Figure 10 yes Figure 7 An enlarged front view of the electric valve. Figure 7 , Figure 10 In the diagram, the stator unit is represented by a sectional view. Figure 10 This indicates the state in which the housing is inserted into the opening of the stator unit until it reaches the installation position.

[0076] The electric valve 1A has a cover 40A, which has ribs 48. Apart from the cover 40A, the electric valve 1A has the same structure as the electric valve 1 described above.

[0077] Cover 40A is made of synthetic resin. Cover 40A is manufactured by injection molding. Cover 40A has a cap shape. Cover 40A integrally has a peripheral wall portion 41 and an upper end wall portion 42. A dome 43 protruding upward is formed in the upper end wall portion 42 at the part opposite to the housing 20.

[0078] like Figure 8 , Figure 9 As shown, the dome 43 has linearly extending ribs 48 on its inner surface. The ribs 48 protrude downwards from the inner surface of the dome 43 (towards the lower end 41b of the peripheral wall portion 41). The ribs 48 are coaxially arranged with the housing 20 and have a circular shape with a diameter smaller than the outer diameter of the housing 20. Alternatively, the ribs 48 can also be elliptical, or multiple arc shapes formed by partially cutting off the circumference, etc. The thickness of the top of the dome 43 is smaller than the thickness from the outer surface of the dome 43 to the top surface 48a of the rib 48.

[0079] In the electric valve 1A, when the housing 20 is inserted into the opening 30a of the stator unit 30 until the specified installation position, the housing 20 is held by the stator unit 30, and the rib 48 is configured to face the ceiling portion 22 with a gap in the vertical direction. Moreover, when the housing 20 is inserted into the opening 30a to a position deeper than the installation position, the housing 20 is disposed at a contact position where the top surface 48a of the rib 48 and the ceiling portion 22 are in surface contact. When the housing 20 is disposed at the contact position, the housing 20 can move toward the installation position, and the housing 20 is not held by the stator unit 30. Thus, when the housing 20 is disposed at the installation position, the ceiling portion 22 and the rib 48 are disposed with a gap, and the housing 20 is held by the stator unit 30. Therefore, even if vibration is transmitted to the electric valve 1A, it is possible to avoid the dome portion 43 from repeatedly colliding with the ceiling portion 22 of the housing 20. In addition, when the housing 20 is disposed at the contact position deeper than the installation position, the ceiling portion 22 of the housing 20 is in surface contact with the rib 48 of the cover 40A, and it is possible to avoid the force for inserting the housing 20 from concentrating at one point. Therefore, breakage of the cover 40A of the stator unit 30 can be suppressed.

[0080] In addition, the rib 48 is disposed coaxially with the housing 20 and has a circular shape, and the circular shape has a diameter smaller than the outer diameter of the housing 20. Thus, when the ceiling portion 22 hits the rib 48, the dome portion 43 can be more evenly stressed. Therefore, breakage of the cover 40A can be more effectively suppressed.

[0081] In addition, the cylindrical portion 21 of the housing 20 has a plurality of hemispherical protrusions 23. The stator unit 30 has a plurality of holding pieces 56 disposed opposite to the outer peripheral surface of the cylindrical portion 21. The plurality of holding pieces 56 have a holding portion 56a that holds the protrusion 23 when the housing 20 is disposed at the installation position. The size D1 of the holding portion 56a in the vertical direction is not more than the diameter D2 of the protrusion 23. When the length in the vertical direction from the center of the holding portion 56a in the vertical direction to the rib 48 is set as L3, the length in the vertical direction from the center of the protrusion 23 to the portion P2 in the ceiling portion 22 that contacts the rib 48 is set as L4, and the size of the holding portion 56a in the vertical direction is set as D1, the electric valve 1A satisfies "L3 - L4 < D1 / 2". In a state where the ceiling portion 22 and the rib 48 are in contact, the center of the protrusion 23 is located inside the holding portion 56a and at a portion closer to the dome portion 43 than the center of the holding portion 56a in the vertical direction. At this time, the holding piece 56 is elastically deformed, and by the restoring force of the holding piece 56, the housing 20 moves to a position where the center of the protrusion 23 coincides with the center of the holding portion 56a in the vertical direction (installation position). Thereby, the housing 20 can be correctly positioned with respect to the stator unit 30. In addition, in the present embodiment, the size of the gap between the ceiling portion 22 of the housing 20 and the rib 48 when the housing 20 is located at the installation position is such that the ceiling portion 22 and the rib 48 do not collide even if the electric valve 1A vibrates, and is preferably 0.5 to 3 mm.

[0082] Furthermore, the thickness of the top of the dome 43 is smaller than the thickness from the outer surface of the dome 43 to the top surface 48a of the rib 48. In this way, the thickness of the dome 43 can be reduced, which can suppress the shrinkage of the resin that may occur during the molding of the cover 40A.

[0083] The embodiments of the present invention have been described above, but the present invention is not limited to the structure of the embodiments. Those skilled in the art can appropriately add, remove, or modify the constituent elements or combine the features of the embodiments as appropriate, provided that such modifications do not violate the spirit of the present invention, and these modifications are also included within the scope of the present invention.

Claims

1. An electric valve having a valve main body, a housing attached to the valve main body, and a stator unit attached to an outer side of the housing, characterized in that, the housing has a cylindrical portion and a ceiling portion provided in connection with one end of the cylindrical portion, the stator unit has a cap-shaped cover, a cylindrical stator disposed on an inner side of the cover, and a molded member made of a filling resin filled between the stator and the cover, the stator unit has an opening for the housing to be inserted in an axial direction, the cover has a dome portion on an inner side of which the ceiling portion is disposed, the housing is held to the stator unit at a mounting position where the ceiling portion and the dome portion are spaced apart from each other in the axial direction, the housing is movable toward the mounting position at a contact position where the ceiling portion and the dome portion are in contact with each other in the axial direction, an angular portion is provided on an inner surface of the dome portion, the angular portion and the ceiling portion are spaced apart from each other in the axial direction when the housing is disposed at the mounting position, the angular portion and the ceiling portion are in line contact with each other when the housing is disposed at the contact position, the cylindrical portion of the housing has a plurality of semispherical protrusions, the stator unit has a plurality of holding pieces disposed in opposition to an outer peripheral surface of the cylindrical portion, the plurality of holding pieces have holding portions made of through holes or recesses that hold the protrusions when the housing is disposed at the mounting position, a size of the holding portions in the axial direction is equal to or smaller than a diameter of the protrusions, a length from a center of the holding portions in the axial direction to the angular portion is set as LI, a length from a center of the protrusions to a position in the ceiling portion in contact with the angular portion in the axial direction is set as L2, and a size of the holding portions in the axial direction is set as Dl, the electric valve satisfies the following formula (1): L1 - L2 < D1 / 2... (1), and a center of each of the holding portions in the axial direction coincides with a center of the corresponding protrusion at the mounting position.

2. The electric valve according to claim 1, characterized in that, the dome portion is disposed to be spaced apart from the ceiling portion in the axial direction when the housing is inserted into the opening until the mounting position, and the housing is disposed at the contact position when the housing is inserted into the opening until a position deeper than the mounting position.

3. The electric valve according to claim 1, characterized in that, the angular portion is disposed coaxially with the housing and has a circular shape or a circular arc shape having a diameter smaller than an outer diameter of the housing.

4. The electric valve according to any one of claims 1 to 3, characterized in that, a thickness of a top portion of the dome portion is smaller than a thickness from an outer surface of the dome portion to the angular portion.

5. An electric valve having a valve main body, a housing attached to the valve main body, and a stator unit attached to an outer side of the housing, characterized in that, the housing has a cylindrical portion and a ceiling portion provided in connection with one end of the cylindrical portion, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The stator unit has a cap-shaped cover, a cylindrical stator arranged inside the cover, and a molded member made of a filling resin filled between the stator and the cover, The stator unit has an opening into which the housing is inserted in the axial direction, The cover has a dome portion, and the ceiling portion is arranged inside the dome portion, In a mounting position where the ceiling portion and the dome portion are spaced apart in the axial direction, the housing is held to the stator unit, In a contact position where the ceiling portion and the dome portion are in contact in the axial direction, the housing is movable toward the mounting position, The dome portion has a rib extending on an inner surface of the dome portion, When the housing is arranged in the mounting position, the rib is spaced apart from the ceiling portion in the axial direction, When the housing is arranged in the contact position, a top end surface of the rib is in surface contact with the ceiling portion, The cylindrical portion of the housing has a plurality of protrusions having a semispherical shape, The stator unit has a plurality of holding pieces arranged opposite to an outer peripheral surface of the cylindrical portion, The plurality of holding pieces have holding portions made of through holes or recesses that hold the protrusions when the housing is arranged in the mounting position, A size of the holding portions in the axial direction is equal to or smaller than a diameter of the protrusions, When a length from a center of the holding portions in the axial direction to the axial direction of the rib is set as L3, a length from a center of the protrusions to a position in the ceiling portion in contact with the rib in the axial direction is set as L4, and a size of the holding portions in the axial direction is set as D1, the electric valve satisfies the following formula (2): L3 - L4 < D1 / 2 … (2), In the mounting position, the center of the axial direction of each of the holding portions coincides with the center of the corresponding protrusion.

6. The electric valve according to claim 5, wherein The rib is arranged coaxially with the housing and has a circular shape or a circular arc shape having a diameter smaller than an outer diameter of the housing.

7. The electric valve according to claim 5 or 6, wherein A thickness of a top portion of the dome portion is smaller than a thickness from an outer surface of the dome portion to a top end surface of the rib.

8. The electric valve according to any one of claims 1 to 3 and 5 to 6, wherein An opening is provided in a top portion of the dome portion.

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