electric valve

Abstract

This invention provides an electric valve capable of suppressing positional misalignment between the valve body and the outer casing caused by welding. The flow control valve has a retainer (40) that positions the outer casing (38) relative to the valve body. The retainer (40) has a cylindrical base portion (41) and an annular outer casing abutment portion (43) that protrudes radially outward from the base portion (41). The retainer (40) is fixed in position relative to the valve body. The outer peripheral surface (43c) of the outer casing abutment portion (43) abuts against the inner peripheral surface (38d) of the outer casing (38) around its entire circumference. Furthermore, the outer casing abutment portion (43) is disposed at a distance from the upper end surface (25e) of the cylindrical component (25) of the valve body in the vertical direction.

Description

Technical Field

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

[0002] Patent Document 1 discloses a flow control valve as an example of a conventional electric valve. This flow control valve has a cylindrical valve body. A cylindrical outer shell is welded to the outer periphery of the upper end face of the valve body. A flange-shaped disc with a guide sleeve is welded to the inner periphery of the upper end face of the valve body. The guide sleeve supports the valve shaft. The valve core is connected to the lower end of the valve shaft. The rotor is connected to the upper end of the valve shaft. A stator is arranged on the outer side of the outer shell.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-71643

[0006] The problem that the invention aims to solve

[0007] In addition to the electric valves described above, there are also electric valves with a positioning component that positions the housing relative to the valve body. The valve body and housing are welded together while in contact with this positioning component.

[0008] exist Figure 6 (a) and (b) schematically show the welded joint between the valve body and the housing of such an electric valve. Figure 6 (a) indicates the state before welding. Figure 6 (b) indicates the state after welding. Figure 6 In (a) and (b), symbol 925 is a cylindrical valve body, symbol 938 is a cylindrical outer shell, and symbol 940 is a positioning component. The positioning component 940 has a cylindrical base portion 941 and an annular outer shell abutment portion 943 that protrudes radially outward from the base portion 941.

[0009] like Figure 6 As shown in (a), the outer peripheral surface 941c of the base portion 941 abuts against the inner peripheral surface 925d of the valve body 925. The outer peripheral surface 943c of the outer shell abutting portion 943 abuts against the inner peripheral surface 938d of the outer shell 938. Furthermore, the lower surface 943a of the outer shell abutting portion 943 abuts against the upper end surface 925e of the valve body 925. The outer shell 938 is positioned relative to the valve body 925 by the positioning member 940.

[0010] And, as Figure 6As shown in (b), when the valve body 925 is welded to the housing 938, the weld B protrudes from the upper end face 925e toward the housing 938 side, and the position of the positioning component 940 may change. As a result, the position of the housing 938 may sometimes be offset relative to the valve body 925, causing the housing to tilt relative to the valve body, or the central axis of the valve body 925 to be offset from the central axis of the housing 938. Summary of the Invention

[0011] Therefore, the object of the present invention is to provide an electric valve capable of suppressing the positional misalignment between the valve body and the housing caused by welding.

[0012] Technical means for solving the problem

[0013] To achieve the above objectives, the electric valve of the present invention comprises: a valve body having a cylindrical portion and a seat portion, the seat portion being configured to block one end of the cylindrical portion; a housing having a cylindrical shape and being welded to the other end of the cylindrical portion; a positioning member abutting against the valve body and the housing; and a valve core that moves axially along the cylindrical portion to open and close a valve port provided in the seat portion, characterized in that the positioning member has a base portion fixed relative to the valve body, and a housing abutting portion protruding from the base portion and abutting against the inner circumferential surface of the housing, the housing abutting portion being disposed axially spaced apart from the other end of the cylindrical portion.

[0014] In this invention, preferably, the size of the interval is more than 1 / 4 and less than 1 times the size of the weld formed by welding the cylindrical portion to the outer shell along the axial direction.

[0015] In this invention, preferably, the base portion has a fitting hole that opens toward the other end of the cylindrical portion, and the positioning member also has a fitting portion that protrudes from the base portion toward one end of the cylindrical portion and fits into the fitting hole.

[0016] In this invention, preferably, the outer peripheral surface of the base portion abuts against the inner peripheral surface of the cylindrical portion.

[0017] Invention Effects

[0018] According to the present invention, the housing abutment portion of the positioning member is arranged axially spaced apart from the other end of the cylindrical portion of the welded housing. This prevents the weld from reaching the housing abutment portion even if the weld bulges from the cylindrical portion towards the housing side. Therefore, positional misalignment between the valve body and the housing caused by welding can be suppressed. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of the flow control valve according to the first embodiment of the electric valve of the present invention.

[0020] Figure 2 yes Figure 1 A cross-sectional view of the flow control valve.

[0021] Figure 3 It means Figure 1 A cross-sectional view of the welded joints of the valve body and housing of the flow control valve.

[0022] Figure 4 This is a cross-sectional view of a flow control valve according to a second embodiment of the electric valve of the present invention.

[0023] Figure 5 It means Figure 4 A cross-sectional view of the welded joints of the valve body and housing of the flow control valve.

[0024] Figure 6 It is a cross-sectional view showing the welded joints of the valve body and housing of an existing electric valve.

[0025] Symbol Explanation

[0026] (First Embodiment)

[0027] 1…Flow control valve, 5…Valve body, 10…Base component, 11…Peripheral wall, 12…Bottom wall, 13…Valve chamber, 14…Circular hole, 15…Flat surface, 16…Inflow hole, 17…Valve port, 18…Pressure equalization hole, 19…Valve seat, 22…Connecting groove, 23…Connecting passage, 24…Back pressure chamber, 25…Cylindrical component, 25a…Lower end, 25b…Upper end, 25e…Upper end face, 26…First conduit, 27…Second conduit, 30…Valve core, 31…Body section, 32…Top end, 32a…Linear characteristic section, 32b…Proportional characteristic section, 33…Annular protrusion, 34…Valve shaft, 34d…Spring support section, 35…Large diameter section, 36…Small diameter section, 38…Outer shell, 38a…Lower end, 38d…Inner peripheral surface, 40…Retaining member, 41 …base portion, 41a…lower surface, 41b…upper surface, 41f…press-in hole, 41g…shaft hole, 41h…flow hole, 42…fitting portion, 42a…hole, 43…outer shell abutment portion, 43c…outer peripheral surface, 45…retaining component, 46…closing component, 46a…O-ring, 46b…gasket, 50…guide bushing, 51…support portion, 51c…male thread, 52…joint portion, 60…valve core drive portion, 61…rotor, 62…stator, 63…valve shaft retainer, 63a…peripheral wall portion, 63b…upper wall portion, 63c…female thread, 63d…through hole, 64…stopping mechanism, 64a…lower stop body, 64b…upper stop body, 65…press nut, 66…valve closing spring, 67…support ring, 68…return spring, B1…weld

[0028] (Second Embodiment)

[0029] 101…Flow control valve, 105…Valve body, 110…Seat assembly, 113…Valve chamber, 117…Valve port, 119…Valve seat, 124…Back pressure chamber, 125…Cylindrical assembly, 125a…Lower end, 125b…Upper end, 125d…Inner circumferential surface, 125e…Upper end surface, 126…First conduit, 127…Second conduit, 130…Valve core, 130a…Annular groove, 130b…Space, 131…Peripheral wall, 132…Upper wall, 13… 2a…Press-in hole, 133…Washer, 134…Valve shaft, 135…Large diameter section, 135c…Male thread, 136…Small diameter section, 137…Disc section, 138…Outer shell, 138a…Lower end, 138d…Inner circumferential surface, 140…Retainer, 141…Base section, 141a…Protrusion, 142…Ring component, 143…Outer shell abutment section, 143c…Outer circumferential surface, 144…Guide sleeve, 144a…Lower end, 144b…Upper end, 144… c…Flange, 144d…Valve core support, 144e…Flow hole, 146…Sealing component, 146a…O-ring, 146b…Gasket, 150…Guide sleeve, 151…Cylindrical portion, 151a…First stop, 151b…Second stop, 151c…Female thread, 152…Cylindrical portion, 153…Flanged disc, 160…Valve core drive, 161…Rotor, 161a…Peripheral wall, 161b…Upper wall, 164a…Lower stop Moving body, 164b… Upper stop body, 167… Connecting body, 170… Connecting mechanism, 171… Valve retainer, 171a… Peripheral wall portion, 171b… Bottom wall portion, 171c… Flow hole, 171d… Through hole, 172… Thrust transmission component, 172a… First part, 172b… Second part, 172c… Third part, 172d… Pressure equalization passage, 173… Spring support component, 173a… Flange, 174… Closing valve spring, B2… Weld Detailed Implementation

[0030] (First Embodiment)

[0031] The following is for reference Figures 1-3 The first embodiment of the electric valve of the present invention relates to a flow control valve.

[0032] Figure 1 , Figure 2 This is a cross-sectional view (longitudinal section view) along the axis of the flow control valve according to the first embodiment of the electric valve of the present invention. Figure 2 The stator is omitted from the text. Figure 1 Indicates the valve is closed. Figure 2 This indicates the valve is open. Figure 3 It means Figure 1 A cross-sectional view of the welded joints of the valve body and housing of the flow control valve. Figure 3 (a) indicates the state before welding. Figure 3 (b) indicates the state after welding.

[0033] The flow control valve 1 in this embodiment is, for example, an electric valve used to adjust the refrigerant flow rate in a refrigeration cycle. Furthermore, the flow control valve 101 in the second embodiment described later is the same.

[0034] like Figures 1-3 As shown, the flow control valve 1 has a valve body 5, a valve core 30, a valve shaft 34, a housing 38, a retainer 40 as a positioning component, a guide bushing 50 as a guide component, and a valve core drive part 60.

[0035] The valve body 5 has a base component 10 as a seat and a cylindrical component 25 as a cylindrical part.

[0036] The base component 10 is made of, for example, stainless steel. The base component 10 has a bottomed cylindrical shape. The outer diameter of the base component 10 is equal to the inner diameter of the cylindrical component 25. The base component 10 has a cylindrical peripheral wall portion 11 and a bottom wall portion 12 connected to the lower end of the peripheral wall portion 11. A valve chamber 13 is provided inside the base component 10. The valve chamber 13 is a space with a circular cross-section in the transverse direction (orthogonal to the axis L).

[0037] A circular hole 14 opening upwards is provided in the peripheral wall portion 11. The circular hole 14 is connected to the valve chamber 13. In this embodiment, the diameter of the circular hole 14 is larger than the diameter of the valve chamber 13. An upward-facing annular plane 15 is provided between the valve chamber 13 and the circular hole 14. An inflow hole 16 connected to the valve chamber 13 is provided in the peripheral wall portion 11.

[0038] The bottom wall portion 12 is provided with a valve port 17, a pressure equalizing hole 18, and a valve seat 19. The valve port 17 is a circular hole. The valve port 17 opens into the valve chamber 13 and extends downward from the valve chamber 13. The pressure equalizing hole 18 extends laterally from the valve port 17. The valve port 17 is configured with a diameter smaller than that of the valve chamber 13 and is coaxial with the valve chamber 13 and the circular hole 14. The valve seat 19 is a conical surface in the shape of an annulus. The valve seat 19 is arranged around the valve port 17.

[0039] A connecting groove 22 extending linearly in the vertical direction (axis L direction) is provided on the outer peripheral surface of the base component 10. A pressure equalization hole 18 extends from the valve port 17 into the connecting groove 22.

[0040] The cylindrical component 25 is made of, for example, stainless steel. The cylindrical component 25 is disposed on the outside of the base component 10. The lower end 25a of the cylindrical component 25 is embedded in the base component 10. The lower end 25a of the cylindrical component 25 is blocked by the base component 10. The lower end 25a of the cylindrical component 25 is brazed to the bottom wall portion 12.

[0041] A connecting passage 23 is formed by the connecting groove 22 and the inner circumferential surface of the cylindrical component 25. The valve port 17 is connected to the back pressure chamber 24 via the equalizing hole 18 and the connecting passage 23. The back pressure chamber 24 is defined by the base component 10, the cylindrical component 25, the outer shell 38, and the retainer 40. The back pressure chamber 24 is separated from the valve chamber 13.

[0042] The valve body 5 has a first conduit 26 and a second conduit 27. The first conduit 26 extends laterally through the cylindrical component 25 and is connected to the inlet hole 16. The first conduit 26 is brazed to the cylindrical component 25. The second conduit 27 is connected to the valve port 17. The second conduit 27 is brazed to the bottom wall portion 12.

[0043] The valve core 30 has a body 31, a tip 32, and an annular protrusion 33. The body 31 is cylindrical. The tip 32 is generally conical in shape and faces downward. The tip 32 is connected to the lower end of the body 31. The annular protrusion 33 protrudes laterally from the lower end of the body 31.

[0044] The top portion 32 has a linear characteristic portion 32a and a proportional characteristic portion 32b. The linear characteristic portion 32a is formed to make the rate of change of valve opening proportional to the flow rate. The linear characteristic portion 32a has a downward-facing conical shape. The proportional characteristic portion 32b is formed to make the rate of change of flow rate relative to the change of valve opening constant. The proportional characteristic portion 32b is connected to the upper end of the linear characteristic portion 32a. The proportional characteristic portion 32b has a shape designed to obtain a proportional characteristic or a characteristic similar to it. Such a shape is, for example, an elliptical surface, or a conical surface with a multi-stage conical shape. The multi-stage conical surface is configured in an approximately elliptical manner such that the cone angle increases stepwise as it approaches the valve port 17. Alternatively, the top portion 32 may be entirely conical in shape.

[0045] The valve core 30 is disposed vertically opposite the valve port 17 within the valve chamber 13. The valve core 30 moves vertically to open and close the valve port 17. When the valve core 30 moves away from the valve seat 19, the valve port 17 opens, becoming the open valve state. In the open valve state, the first conduit 26 and the second conduit 27 are connected via the valve chamber 13. When the valve core 30 contacts the valve seat 19, the valve port 17 closes, becoming the closed valve state. In the closed valve state, the first conduit 26 and the second conduit 27 are disconnected.

[0046] The valve shaft 34 is a long cylindrical shape. The valve shaft 34 has a large-diameter portion 35 and a small-diameter portion 36 connected to the upper end of the large-diameter portion 35. The diameter of the small-diameter portion 36 is smaller than the diameter of the large-diameter portion 35. The body 31 of the valve core 30 is connected to the lower end of the large-diameter portion 35. In this embodiment, the valve core 30 and the valve shaft 34 are integrally formed by machining a single piece of metal material (e.g., stainless steel).

[0047] The outer casing 38 is made of, for example, stainless steel. The outer casing 38 has a cylindrical shape with a blocked upper end. The outer diameter of the outer casing 38 is equal to the outer diameter of the cylindrical component 25. The inner diameter of the outer casing 38 is larger than the inner diameter of the cylindrical component 25. The lower end 38a of the outer casing 38 is welded to the upper end face 25e of the upper end 25b, which is the other end of the cylindrical component 25. A weld B1 is formed by welding the cylindrical component 25 to the outer casing 38. Figure 3 ).

[0048] The retainer 40 is made of, for example, stainless steel. The retainer 40 has a base portion 41, a fitting portion 42, and a housing abutment portion 43.

[0049] The base portion 41 is cylindrical. The diameter of the base portion 41 is smaller than the inner diameter of the cylindrical component 25. A cylindrical fitting portion 42 protruding downwards is provided on the lower surface 41a of the base portion 41. A circular press-in hole 41f, coaxially arranged with the fitting portion 42, is provided at the center of the upper surface 41b of the base portion 41. A shaft hole 41g is provided at the center of the bottom surface of the press-in hole 41f. The valve shaft 34 is inserted into the shaft hole 41g. A flow hole 41h extending vertically is provided in the base portion 41. The flow hole 41h connects the back pressure chamber 24 to the space inside the outer casing 38. The base portion 41 and the fitting portion 42 are inserted into the upper end 25b of the cylindrical component 25. The base portion 41 may also have a shape other than a cylinder, such as a quadrangular prism or a hexagonal prism.

[0050] The fitting portion 42 is pressed into the circular hole 14 of the base component 10 until it abuts against the retaining member 45. The fitting portion 42 engages with the circular hole 14, which serves as the fitting hole. Thus, the retaining member 40 and the base component 10 are directly assembled, fixing the lateral and vertical positions of the retaining member 40 relative to the base component 10 (i.e., the valve body 5). The base portion 41 is indirectly fixed relative to the valve body 5 via the fitting portion 42. The body 31 of the valve core 30 and the valve shaft 34 are inserted into the fitting portion 42. The space inside the fitting portion 42 is connected to the back pressure chamber 24 via a hole 42a.

[0051] The outer casing abutment portion 43 is a circular protrusion that projects radially outward from the outer peripheral surface of the base portion 41. The diameter (maximum diameter) of the outer casing abutment portion 43 is equal to the inner diameter of the outer casing 38. The outer peripheral surface 43c of the outer casing abutment portion 43 abuts against the inner peripheral surface 38d of the outer casing 38 throughout its entire circumference. The outer casing abutment portion 43 is embedded in the lower end 38a of the outer casing 38. Alternatively, the outer casing abutment portion 43 may be composed of a plurality of protrusions spaced circumferentially on the outer peripheral surface of the base portion 41.

[0052] The outer casing abutment portion 43 is disposed at a distance from the upper end face 25e of the cylindrical component 25 in the vertical direction. A space is provided between the outer casing abutment portion 43 and the upper end face 25e of the cylindrical component 25. Preferably, the size H1 of the distance between the outer casing abutment portion 43 and the upper end face 25e of the cylindrical component 25 is more than 1 / 4 and less than 1 times the size H2 of the weld seam B1 in the vertical direction. In this way, the positional change of the retainer 40 due to the weld seam B1 can be effectively prevented, and the enlargement of the flow control valve 1 can be suppressed.

[0053] The fitting portion 42 of the retainer 40 engages with the circular hole 14 of the base component 10, fixing the retainer 40 in position relative to the base component 10. Furthermore, the outer peripheral surface 43c of the outer shell abutment portion 43 of the retainer 40 abuts against the inner peripheral surface 38d of the outer shell 38. Thus, the retainer 40 positions the outer shell 38 relative to the valve body 5, coaxially arranging the valve body 5 and the outer shell 38.

[0054] The retaining member 45 holds the closing member 46 inside the base member 10. The retaining member 45 has an annular shape. The retaining member 45 is sandwiched between the fitting portion 42 and the plane 15 of the base member 10. The annular closing member 46 is disposed inside the retaining member 45. The body 31 of the valve core 30 is embedded inside the closing member 46. In this embodiment, the closing member 46 has an annular gasket 46b made of polytetrafluoroethylene (PTFE) disposed inside the O-ring 46a made of rubber material. The gasket 46b is pressed by the outer peripheral surface of the body 31 of the valve core 30.

[0055] A sealing member 46 is disposed between the valve chamber 13 and the back pressure chamber 24. In this embodiment, the diameter of the body 31 of the valve core 30 (i.e., the diameter of the portion sealed by the sealing member 46) is equal to the diameter of the valve port 17. Therefore, in the closed state, the difference (differential pressure) between the refrigerant pressure applied to the valve core 30 from the valve port 17 side and the refrigerant pressure applied to the valve core 30 from the back pressure chamber 24 side can be eliminated, or the difference (differential pressure) can be made very small. Furthermore, the diameter of the body 31 may differ from the diameter of the valve port 17, but to reduce the aforementioned differential pressure, it is preferable to reduce the difference between the diameter of the body 31 and the diameter of the valve port 17.

[0056] The guide bushing 50 has a support portion 51 and a connecting portion 52. The support portion 51 is cylindrical. A male thread 51c is provided on the outer peripheral surface of the support portion 51. The connecting portion 52 is cylindrical with a diameter larger than that of the support portion 51. The connecting portion 52 is connected to the lower end of the support portion 51. The inner diameter of the support portion 51 is equal to the inner diameter of the connecting portion 52. The connecting portion 52 is pressed into the pressing hole 41f of the retainer 40, and the retainer 40 is engaged with the guide bushing 50. The guide bushing 50 is mounted on the retainer 40. The guide bushing 50 supports the valve shaft 34 so that it can rotate about the axis L and move in the vertical direction. In this embodiment, the retainer 40 and the guide bushing 50 are independent components, assembled by pressing the retainer 40 and the guide bushing 50 together. For example, the retainer 40 and the guide bushing 50 can also be integrally formed by machining a piece of metal.

[0057] The valve core drive unit 60 moves the valve core 30 vertically via the valve shaft 34. The valve core 30 contacts and separates from the valve seat 19 via the valve core drive unit 60. The valve core drive unit 60 includes a rotor 61, a stator 62, a valve shaft retainer 63, and a stop mechanism 64.

[0058] The rotor 61 is cylindrical. The rotor 61 is arranged inside the housing 38 and is capable of rotation. The stator 62 is arranged outside the housing 38. The rotor 61 and stator 62 constitute a stepper motor.

[0059] The valve shaft retainer 63 has a cylindrical shape with its upper end blocked. The valve shaft retainer 63 has a cylindrical peripheral wall portion 63a and an upper wall portion 63b connected to the upper end of the peripheral wall portion 63a. A female thread 63c is provided on the inner peripheral surface of the peripheral wall portion 63a. The female thread 63c engages with the male thread 51c of the guide bushing 50. A through hole 63d is provided in the upper wall portion 63b. The small-diameter portion 36 of the valve shaft 34 is inserted into the through hole 63d. A pressing nut 65 is fixedly installed in the small-diameter portion 36. A valve-closing spring 66 is provided between the spring support portion 34d, which is a step portion between the large-diameter portion 35 and the small-diameter portion 36 of the valve shaft 34, and the upper wall portion 63b, to push the valve shaft 34 downwards. The valve-closing spring 66 is a compression coil spring. By pressing the nut 65 and the valve-closing spring 66, the valve shaft 34 moves vertically along with the movement of the valve shaft retainer 63. The support ring 67 is riveted and fixed to the upper wall 63b. The upper wall 63b is connected to the rotor 61 via the support ring 67. When the rotor 61 rotates, the valve shaft retainer 63 also rotates. When the valve shaft retainer 63 rotates, it moves vertically due to the thread feed action of the male thread 51c and the female thread 63c. A return spring 68 is provided above the valve shaft retainer 63. The return spring 68 is a component used to easily re-engage the male thread 51c and the female thread 63c if they become disengaged.

[0060] The stop mechanism 64 has a lower stop body 64a and an upper stop body 64b. The lower stop body 64a is fixed to the guide bushing 50. The upper stop body 64b is fixed to the valve shaft retainer 63. When the valve shaft retainer 63 reaches the lower limit position, the upper stop body 64b of the stop mechanism 64 abuts against the lower stop body 64a, thereby restricting the downward movement of the valve shaft retainer 63.

[0061] In the flow control valve 1, the valve body 5 (base component 10, valve port 17, valve seat 19, cylindrical component 25), valve core 30, valve shaft 34, housing 38, retainer 40 (base part 41, fitting part 42, housing abutment part 43), guide bushing 50 and rotor 61 are arranged such that their respective central axes are aligned with axis L.

[0062] Next, an example of the operation of flow control valve 1 will be described.

[0063] In the flow control valve 1, the stator 62 is energized to rotate the rotor 61 in one direction. The valve shaft retainer 63 rotates together with the rotor 61, and the rotor 61 and the valve shaft retainer 63 move downwards due to the thread feed action of the female thread 63c of the valve shaft retainer 63 and the male thread 51c of the guide bushing 50. The valve shaft 34 also moves downwards together with the valve shaft retainer 63, thereby closing the valve port 17 (closed state) with the valve core 30.

[0064] Alternatively, in flow control valve 1, the stator 62 is energized to rotate the rotor 61 in the opposite direction. The valve shaft retainer 63 rotates together with the rotor 61, and the rotor 61 and valve shaft retainer 63 move upwards due to the threaded feed action of the female thread 63c of the valve shaft retainer 63 and the male thread 51c of the guide bushing 50. The valve shaft 34 also moves upwards together with the valve shaft retainer 63, thereby opening the valve port 17 (open valve state) with the valve core 30.

[0065] Next, an example of the assembly method of the flow control valve 1 described above will be explained.

[0066] The base component 10 is embedded into the lower end 25a of the cylindrical component 25, and the bottom wall portion 12 of the base component 10 is brazed to the cylindrical component 25. The first conduit 26 is connected to the inlet hole 16, and the cylindrical component 25 is brazed to the first conduit 26. The second conduit 27 is connected to the valve port 17, and the bottom wall portion 12 is brazed to the second conduit 27.

[0067] A stop body 64a is installed on the guide bushing 50. A stop body 64b is installed on the valve shaft retainer 63. The rotor 61 is connected to the valve shaft retainer 63 via a support ring 67. The mating portion 52 of the guide bushing 50 is pressed into the pressing hole 41f of the retainer 40. The valve core 30 is embedded inside the closing member 46 held by the retaining member 45. The valve shaft 34 is inserted into the fitting portion 42 of the retainer 40, the shaft hole 41g of the retainer 40, and the guide bushing 50. A valve closing spring 66 is arranged on the spring support portion 34d of the valve shaft 34. The female thread 63c of the valve shaft retainer 63 is screwed into the male thread 51c of the guide bushing 50. The small diameter portion 36 of the valve shaft 34 is inserted into the through hole 63d of the upper wall portion 63b of the valve shaft retainer 63. A pressing nut 65 is fixedly installed on the small diameter portion 36, and a return spring 68 is arranged thereon.

[0068] The valve core 30, retaining member 45, and sealing member 46 are inserted into the circular hole 14 of the base member 10. The fitting portion 42 of the retaining member 40 is pressed into the circular hole 14 until it abuts against the retaining member 45. Thus, the retaining member 40 is fixed in position relative to the valve body 5. The retaining member 40 is coaxially disposed with the valve body 5. In addition, the outer shell abutting portion 43 of the retaining member 40 is disposed at a distance from the upper end face 25e of the cylindrical member 25 in the vertical direction.

[0069] The lower end 38a of the outer casing 38 is embedded with the outer casing abutment portion 43. This abuts the lower end 38a of the outer casing 38 against the upper end face 25e of the cylindrical component 25. A guide bushing 50, a rotor 61, and a valve shaft retainer 63 are disposed inside the outer casing 38. The lower end 38a abuts against the upper end face 25e, thereby fixing the vertical position of the outer casing 38. In this state, as... Figure 3 As shown in (a), the outer peripheral surface 43c of the outer casing abutment portion 43 abuts against the inner peripheral surface 38d of the outer casing 38 throughout its entire circumference. The cylindrical component 25 is coaxially arranged with the outer casing 38 by means of the retainer 40.

[0070] The cylindrical component 25 is welded to the outer casing 38 throughout its entire circumference. For example... Figure 3 As shown in (b), although weld B1 protrudes from the upper end face 25e of cylindrical component 25 toward the outer casing 38 through welding, it remains within the space between the upper end face 25e of cylindrical component 25 and the abutment portion 43 of outer casing. Therefore, weld B1 can prevent the position of retainer 40 from being altered.

[0071] Furthermore, a stator 62 is installed on the outside of the housing 38. This completes the flow control valve 1.

[0072] As described above, in the flow control valve 1 of this embodiment, the housing abutment portion 43 of the retainer 40 is arranged at a distance from the upper end face 25e of the cylindrical member 25 in the vertical direction. This prevents the weld B1 from reaching the housing abutment portion 43 even if the weld B1 protrudes from the cylindrical member 25 towards the housing 38. Therefore, positional misalignment between the valve body 5 and the housing 38 caused by welding can be suppressed.

[0073] (Second Embodiment)

[0074] The following is for reference Figure 4 , Figure 5 A flow control valve relating to a second embodiment of the electric valve of the present invention will be described.

[0075] Figure 4 This is a longitudinal cross-sectional view of a flow control valve according to a second embodiment of the electric valve of the present invention. Figure 4 The stator is omitted from the text. Figure 4 This indicates that the valve is closed. Figure 5 It means Figure 4 A cross-sectional view of the welded parts of the valve body and shell of the flow control valve. Figure 5 (a) indicates the state before welding. Figure 5 (b) indicates the state after welding.

[0076] like Figure 4 As shown, the flow control valve 101 includes a valve body 105, a valve core 130, a valve shaft 134, a connecting mechanism 170, a housing 138, a retainer 140 as a positioning component, a guide sleeve 144, a guide sleeve 150 as a guide portion, and a valve core drive portion 160.

[0077] The valve body 105 has a seat member 110 as a seat portion and a cylindrical member 125 as a cylindrical portion. A valve chamber 113 is provided inside the valve body 105.

[0078] The seat component 110 is made of, for example, stainless steel. The seat component 110 is cylindrical. The seat component 110 has a valve port 117 and a valve seat 119. The valve port 117 is a circular orifice. The valve port 117 opens into the valve chamber 113. The valve seat 119 is a conical surface in the shape of an annulus. The valve seat 119 is arranged around the valve port 117.

[0079] The cylindrical component 125 is made of, for example, stainless steel. The lower end 125a, which is one end of the cylindrical component 125, is embedded in the seat component 110. The lower end 125a of the cylindrical component 125 is blocked by the seat component 110. The lower end 125a of the cylindrical component 125 is brazed to the seat component 110. In this embodiment, the seat component 110 and the cylindrical component 125 are separate components, joined together by brazing. For example, the valve body 105 can also be formed by machining a piece of metal or stamping a metal sheet, the valve body 105 integrally having a cylindrical portion and a seat portion that blocks one end of this cylindrical portion.

[0080] The valve body 105 has a first conduit 126 and a second conduit 127. The first conduit 126 extends laterally through the cylindrical component 125 and is connected to the valve chamber 113. The first conduit 126 is brazed to the cylindrical component 125. The second conduit 127 is connected to the valve port 117. The second conduit 127 is brazed to the seat component 110.

[0081] The valve core 130 is made of, for example, stainless steel. The valve core 130 has a cylindrical shape with its upper end blocked. The valve core 130 has a cylindrical peripheral wall portion 131 and an upper wall portion 132 connected to the upper end of the peripheral wall portion 131. A press-in hole 132a is provided in the upper wall portion 132. A washer 133 is disposed on the upper surface of the upper wall portion 132. The outer diameter of the washer 133 is equal to the outer diameter of the valve core 130. The inner diameter of the washer 133 is slightly larger than the diameter of the press-in hole 132a. The washer 133 is fixed to the upper wall portion 132 by a thrust transmission member 172 of the connecting mechanism 170. The thrust transmission member 172 is inserted into the washer 133 and pressed into the press-in hole 132a. The washer 133, together with the cutout on the peripheral portion of the upper surface of the upper wall portion 132, forms an annular groove 130a. A closing component 146 is disposed in this annular groove 130a.

[0082] The valve core 130 and valve port 117 are arranged opposite each other in the vertical direction (axis L direction). The valve core 130 (specifically, the lower end of the peripheral wall portion 131) contacts and separates from the valve seat 119. When the valve core 130 leaves the valve seat 119, the valve port 117 opens, becoming an open valve. In the open valve state, the first conduit 126 and the second conduit 127 are connected via the valve chamber 113. When the valve core 130 contacts the valve seat 119, the valve port 117 closes, becoming a closed valve. In the closed valve state, the first conduit 126 and the second conduit 127 are disconnected.

[0083] The valve shaft 134 is made of, for example, stainless steel. The valve shaft 134 has an elongated cylindrical shape. The valve shaft 134 has a large-diameter portion 135, a small-diameter portion 136 connected to the upper end of the large-diameter portion 135, and a disc portion 137 connected to the lower end of the large-diameter portion 135. The diameter of the small-diameter portion 136 is smaller than the diameter of the large-diameter portion 135. The diameter of the disc portion 137 is larger than the diameter of the large-diameter portion 135. A male thread 135c is provided on the outer circumferential surface of the large-diameter portion 135. A lower stop 164a is fixed to the lower end of the large-diameter portion 135. An upper stop 164b is fixed to the upper end of the large-diameter portion 135. The lower stop 164a and the upper stop 164b rotate together with the valve shaft 134 and move together with the valve shaft 134 in the vertical direction.

[0084] The connecting mechanism 170 connects the valve core 130 to the valve shaft 134. The connecting mechanism 170 includes a valve retainer 171, a thrust transmission component 172, a spring support component 173, and a valve closing spring 174.

[0085] The valve retainer 171 has a bottomed cylindrical shape. The valve retainer 171 has a cylindrical peripheral wall portion 171a and a bottom wall portion 171b connected to the lower end of the peripheral wall portion 171a. The outer diameter of the peripheral wall portion 171a is equal to the outer diameter of the valve core 130. The upper end of the peripheral wall portion 171a is riveted and fixed to the periphery of the disc portion 137 of the valve shaft 134. A flow hole 171c is provided in the peripheral wall portion 171a. A through hole 171d is provided in the bottom wall portion 171b. A thrust transmission member 172 is inserted into the through hole 171d.

[0086] The thrust transmission component 172 is cylindrical. The thrust transmission component 172 has a first part 172a, a second part 172b, and a third part 172c. The first part 172a, the second part 172b, and the third part 172c are connected sequentially from bottom to top. The diameter of the second part 172b is larger than the diameter of the first part 172a. The diameter of the third part 172c is larger than the diameter of the second part 172b and the diameter of the through hole 171d of the valve retainer 171. The first part 172a is pressed into the press-in hole 132a of the valve core 130. The second part 172b is inserted into the through hole 171d of the valve retainer 171. The thrust transmission component 172 has a stepped portion between the first part 172a and the second part 172b, and a washer 133 is sandwiched between this stepped portion and the upper surface of the upper wall portion 132 of the valve core 130.

[0087] The thrust transmission component 172 is provided with a pressure equalization passage 172d extending from a first portion 172a to a third portion 172c. The pressure equalization passage 172d opens downward in the first portion 172a and laterally in the third portion 172c. The pressure equalization passage 172d connects the space 130b inside the valve core 130 to the space inside the valve retainer 171.

[0088] The spring support component 173 has a cylindrical shape and a flange 173a protruding radially outward at its lower end. The valve closing spring 174 is a compression helical spring. The valve closing spring 174 is disposed between the disc portion 137 of the valve shaft 134 and the flange 173a of the spring support component 173. The valve closing spring 174 pushes the lower surface of the spring support component 173 toward the thrust transmission component 172, and pushes the third part 172c of the thrust transmission component 172 toward the bottom wall portion 171b of the valve retainer 171.

[0089] When the valve retainer 171 moves upward together with the valve shaft 134, the third part 172c of the thrust transmission component 172 is caught by the bottom wall portion 171b, and the thrust transmission component 172 also moves upward. When the valve retainer 171 moves downward together with the valve shaft 134, the thrust transmission component 172, which is pressed against the bottom wall portion 171b of the valve retainer 171, moves downward via the valve closing spring 174. As the thrust transmission component 172 moves vertically, the valve core 130 moves vertically.

[0090] The outer casing 138 is made of, for example, stainless steel. The outer casing 138 has a cylindrical shape with a blocked upper end. The outer diameter of the outer casing 138 is approximately equal to the outer diameter of the cylindrical component 125. The inner diameter of the outer casing 138 is larger than the inner diameter of the cylindrical component 125. The lower end 138a of the outer casing 138 is welded to the upper end face 125e of the upper end 125b of the cylindrical component 125. Weld B2 is formed by welding the cylindrical component 125 to the outer casing 138. Figure 5 ).

[0091] The retainer 140 is made of, for example, stainless steel. The retainer 140 has a base portion 141 and a housing abutment portion 143.

[0092] The base portion 141 is cylindrical. The outer diameter of the base portion 141 is equal to the inner diameter of the cylindrical component 125. An annular protrusion 141a protruding radially inward is provided at the lower end of the base portion 141. The base portion 141 is embedded in the upper end 125b of the cylindrical component 125. The base portion 141 is directly fixed relative to the valve body 105. Figure 5 As shown, the outer peripheral surface 141c of the base portion 141 abuts against the inner peripheral surface 125d of the cylindrical member 125 all around its circumference. The base portion 141 may also partially contact the inner peripheral surface 125d of the cylindrical member 125, for example, it may have a shape other than a cylindrical shape such as a quadrilateral cylindrical or a hexagonal cylindrical.

[0093] The outer casing abutment portion 143 is an annular protrusion that projects radially outward from the outer peripheral surface 141c of the base portion 141. The diameter (maximum diameter) of the outer casing abutment portion 143 is equal to the inner diameter of the outer casing 138. The outer casing abutment portion 143 is inserted into the lower end 138a of the outer casing 138. Figure 5 As shown, the outer peripheral surface 143c of the outer casing abutment portion 143 abuts against the inner peripheral surface 138d of the outer casing 138 throughout its entire circumference. Alternatively, the outer casing abutment portion 143 may be composed of a plurality of protrusions spaced apart from the outer peripheral surface 141c of the base portion 141 in the circumferential direction.

[0094] The outer casing abutment portion 143 is spaced apart from the upper end face 125e of the cylindrical component 125 in the vertical direction. A space is provided between the outer casing abutment portion 143 and the upper end face 125e of the cylindrical component 125. Preferably, the size H3 of the gap between the outer casing abutment portion 143 and the upper end face 125e of the cylindrical component 125 is more than 1 / 4 and less than 1 times the size H4 of the weld seam B2 in the vertical direction. In this way, the position of the retainer 140 can be effectively prevented from changing due to the weld seam B2, and the enlargement of the flow control valve 101 can be suppressed.

[0095] The guide sleeve 144 has a cylindrical shape. The lower end 144a of the guide sleeve 144 abuts against the seat member 110. A flange 144c protruding radially outward is provided at the upper end 144b of the guide sleeve 144. The flange 144c is clamped by the protrusion 141a of the base portion 141 and the ring member 142 pressed into the inner side of the base portion 141. The guide sleeve 144 positions the retainer 140 relative to the valve body 105 in the vertical direction.

[0096] A valve core support portion 144d is provided at the center of the guide sleeve 144 in the vertical direction. The inner diameter of the valve core support portion 144d is equal to the outer diameter of the valve core 130. The valve core 130 and the valve retainer 171 are housed in the valve core support portion 144d in a manner that allows them to move vertically. The valve core support portion 144d supports the valve core 130 and the valve retainer 171 so that they can move vertically. A plurality of flow holes 144e are provided in the guide sleeve 144 below the valve core support portion 144d. The flow holes 144e connect the valve chamber 113 to the space inside the guide sleeve 144.

[0097] The base portion 141 of the retainer 140 is embedded in the upper end of the cylindrical member 125, and the outer peripheral surface 141c of the base portion 141 abuts against the inner peripheral surface 125d of the cylindrical member 125. This fixes the lateral position of the retainer 140. Furthermore, the vertical position of the retainer 140 is fixed by the guide sleeve 144. Also, the outer peripheral surface 143c of the outer shell abutting portion 143 of the retainer 140 abuts against the inner peripheral surface 138d of the outer shell 138. This positions the outer shell 138 relative to the valve body 105. By the abutment between the cylindrical member 125 of the valve body 105 and the outer shell 138 and the retainer 140, the valve body 105 and the outer shell 138 are coaxially arranged.

[0098] The flow control valve 101 has a back pressure chamber 124 defined by the housing 138, the retainer 140, and the guide sleeve 144. The back pressure chamber 124 is separated from the valve chamber 113. In the closed state, the valve port 117 is connected to the back pressure chamber 124 via the space 130b inside the valve core 130, the pressure equalization passage 172d, and the flow hole 171c of the valve retainer 171.

[0099] The sealing member 146 is annular in shape. The sealing member 146 is housed in an annular groove 130a. In this embodiment, a polytetrafluoroethylene (PTFE) annular gasket 146b is disposed outside the O-ring 146a made of rubber material. The gasket 146b is pressed against the inner circumferential surface of the valve core support portion 144d of the guide sleeve 144.

[0100] A sealing member 146 is disposed between the valve chamber 113 and the back pressure chamber 124. In this embodiment, the inner diameter of the valve core support portion 144d of the guide sleeve 144 (i.e., the diameter of the portion sealed by the sealing member 146) is equal to the diameter of the valve port 117. Therefore, in the closed valve state, the difference (differential pressure) between the refrigerant pressure applied to the valve core 130 from the valve port 117 side and the refrigerant pressure applied to the valve core 130 from the back pressure chamber 124 side can be eliminated, or the difference (differential pressure) between the refrigerant pressure applied to the valve core 130 from the valve port 117 side and the refrigerant pressure applied to the valve core 130 from the back pressure chamber 124 side can be made very small.

[0101] The guide sleeve 150 has a cylindrical portion 151, a cylindrical portion 152, and a flanged disc 153. A first stop 151a is provided at the lower end of the cylindrical portion 151. A second stop 151b is provided at the upper end of the cylindrical portion 151. When the valve shaft 134 reaches the upper limit position, the lower stop 164a abuts against the first stop 151a, restricting the upward movement of the valve shaft 134. When the valve shaft 134 reaches the lower limit position, the upper stop 164b abuts against the second stop 151b, restricting the downward movement of the valve shaft 134. A female thread 151c extending in the vertical direction is provided in the cylindrical portion 151. The male thread 135c of the valve shaft 134 engages with the female thread 151c. The cylindrical portion 152 is connected to the lower end of the cylindrical portion 151. A disc portion 137 of the valve shaft 134, a lower stop 164a, and a connecting mechanism 170 are inserted into the cylindrical portion 152. The cylindrical portion 152 supports the connecting mechanism 170 so that it can move in the vertical direction. The flange-shaped disc 153 is annular in shape. The inner peripheral edge of the flange-shaped disc 153 is embedded in the cylindrical portion 152. The outer peripheral edge of the flange-shaped disc 153 is welded to the inner peripheral edge of the retainer 140.

[0102] The valve core drive unit 160 moves the valve core 130 in the vertical direction. The valve core 130 contacts and separates from the valve seat 119 via the valve core drive unit 160. The valve core drive unit 160 has a rotor 161 and a stator (not shown).

[0103] The rotor 161 has a cylindrical shape with its upper end blocked. The rotor 161 has a cylindrical peripheral wall portion 161a and an upper wall portion 161b connected to the upper end of the peripheral wall portion 161a. The rotor 161 is configured to rotate inside the housing 138. The upper wall portion 161b is connected to the small-diameter portion 136 of the valve shaft 134 via a connecting body 167.

[0104] In the flow control valve 101, the valve body 105 (valve port 117, cylindrical component 125), valve core 130, valve shaft 134, connecting mechanism 170 (valve retainer 171, thrust transmission component 172), housing 138, retainer 140 (base portion 141, housing abutment portion 143), guide sleeve 144, guide sleeve 150 (cylindrical portion 151, cylindrical portion 152, flange-shaped disk 153) and rotor 161 are configured such that their respective central axes are aligned with axis L.

[0105] The flow control valve 101 operates in the same manner as the flow control valve 1 in the first embodiment described above.

[0106] Next, an example of the assembly method of the flow control valve 101 will be described.

[0107] The seat component 110 is embedded into the lower end 125a of the cylindrical component 125, and the seat component 110 and the cylindrical component 125 are brazed together. The first conduit 126 is connected to the valve chamber 113, and the cylindrical component 125 is brazed together with the first conduit 126. The second conduit 127 is connected to the valve port 117, and the seat component 110 and the second conduit 127 are brazed together.

[0108] The ring component 142 is pressed into the retainer 140, and the flange 144c of the guide sleeve 144 is clamped between the protrusion 141a of the retainer 140 and the ring component 142. The valve core 130 is connected to the valve shaft 134 via the connecting mechanism 170. The lower stop 164a is installed on the valve shaft 134. The male thread 135c of the valve shaft 134 is screwed into the female thread 151c of the guide sleeve 150. The upper stop 164b is installed on the valve shaft 134. The rotor 161 is connected to the valve shaft 134 via the connecting body 167. The valve core 130 and the valve retainer 171 are inserted into the valve core support portion 144d of the guide sleeve 144. The flange-shaped disc 153 of the guide sleeve 150 is welded to the retainer 140.

[0109] The guide sleeve 144 is inserted into the cylindrical component 125, and the lower end 144a of the guide sleeve 144 abuts against the seat component 110. The base portion 141 of the retainer 140 is inserted into the upper end 125b of the cylindrical component 125. Thus, the retainer 140 is fixed in position relative to the valve body 105. The retainer 140 is coaxially disposed with the valve body 105. Furthermore, the outer shell abutment portion 143 of the retainer 140 is disposed at a distance from the upper end face 125e of the cylindrical component 125 in the vertical direction.

[0110] The lower end 138a of the outer casing 138 is inserted into the outer casing abutment portion 143, causing the lower end 138a of the outer casing 138 to abut against the upper end face 125e of the cylindrical component 125. A guide sleeve 150 and a rotor 161 are disposed inside the outer casing 138. The vertical position is fixed by the abutment between the lower end 138a of the outer casing 138 and the upper end face 125e. In this state, as... Figure 5 As shown in (a), the outer peripheral surface 141c of the base portion 141 abuts against the inner peripheral surface 125d of the cylindrical member 125 throughout its entire circumference. The outer peripheral surface 143c of the outer shell abutment portion 143 abuts against the inner peripheral surface 138d of the outer shell 138 throughout its entire circumference. The cylindrical member 125 and the outer shell 138 are coaxially arranged by the retainer 140.

[0111] The cylindrical component 125 is welded to the outer casing 138 around its entire circumference. For example... Figure 5 As shown in (b), although weld B2 protrudes from the upper end face 125e of the cylindrical component 125 toward the outer casing 138 through welding, it remains within the space between the upper end face 125e of the cylindrical component 125 and the abutment portion 143 of the outer casing. Therefore, weld B2 can prevent it from changing the position of the retainer 140.

[0112] Furthermore, a stator is installed on the outside of the housing 138. This completes the flow control valve 101.

[0113] The flow control valve 101 in this embodiment can also perform the same function as the flow control valve 1 in the first embodiment described above.

[0114] The embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Techniques that involve appropriate additions, deletions, or design changes to the structural elements of the above embodiments, or appropriate combinations of features of the embodiments, are included within the scope of the present invention as long as they do not contradict its spirit.

Claims

1. An electric valve, comprising: A valve body having a cylindrical portion and a seat portion, the seat portion being configured to block one end of the cylindrical portion; The outer casing is cylindrical in shape and welded to the other end of the cylindrical portion; A positioning component that abuts against the valve body and the housing; and The valve core moves axially along the cylindrical portion to open and close the valve port located on the seat portion. The electric valve is characterized in that: The positioning component has a base portion fixed relative to the valve body, and a housing abutment portion protruding from the base portion and abutting against the inner circumferential surface of the housing. The outer shell abutment portion is disposed axially spaced apart from the other end of the cylindrical portion.

2. The electric valve as described in claim 1, characterized in that, The size of the interval is more than 1 / 4 and less than 1 times the size of the weld formed by welding the cylindrical part to the outer shell along the axial direction.

3. The electric valve as described in claim 1 or 2, characterized in that, The seat portion has a fitting hole that opens toward the other end of the cylindrical portion. The positioning component also has a fitting portion that protrudes from one end of the base portion toward the cylindrical portion and fits into the fitting hole.

4. The electric valve as described in claim 1 or 2, characterized in that, The outer peripheral surface of the base portion abuts against the inner peripheral surface of the cylindrical portion.

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