Motor-operated valve

Abstract

To provide a motor operated valve that ensures waterproofness to a space including a circuit board.SOLUTION: A motor operated valve 1 has a body, a valve element, a rotor 320, a can 302, and a stator unit 360. The stator unit 360 includes a case 400 that has a cylindrical shape and is made of resin, a stator 340 that is arranged in the case 400 and is externally inserted onto the can 302, a circuit board 420 arranged inside the case 400, a power supply terminal 422 connected with the circuit board 420, a connector forming part 402 that integrally has the power supply terminal 422 in the inside and is made of resin, and a lid portion 440 that forms a space S for internally capsuling the circuit board 420 between the lid portion and the case 400. The connector forming portion 402 is formed integrally with the case 400. A first seal portion is provided between an open end 403 on one side of the case 400 and the lid portion 440, and a second seal portion is provided between an open end portion 410 on the other side and the body.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an electrically operated valve, and more particularly to a seal structure. [Background technology]

[0002] Automotive air conditioning systems generally consist of a refrigeration cycle consisting of a compressor, condenser, expansion device, evaporator, and other components. Electric expansion valves, which use a stepping motor as the driver to precisely control the valve opening, are increasingly being adopted as expansion devices. These electric expansion valves have a mechanism for attaching and detaching a valve element supported at the tip of a shaft to a valve seat mounted on the body. For this attachment and detachment, a technology has been proposed that uses a screw feed mechanism to convert the rotational motion of the rotor into the translational motion of the shaft.

[0003] In recent years, electric expansion valves equipped with circuit boards have been increasingly adopted. When a circuit board is installed in an electric expansion valve, it is necessary to isolate the circuit board from the outside air to prevent corrosion of the circuit board. To address this issue, a known embodiment involves multiple molding processes for the stator, and then enclosing the circuit board with the resulting resin molded product and a lid molded in a separate process (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Chinese Patent Application Publication No. 107345590 Summary of the Invention [Problem to be solved by the invention]

[0005] In the motor-operated expansion valve described in Patent Document 1, the stator is molded twice. However, when a resin molded product obtained by the first molding is subjected to a second molding to obtain a resin molded product, it is difficult to ensure airtightness between the two resin molded products (at the resin-contacting portion). In the motor-operated expansion valve described in Patent Document 1, the resin-contacting portion extends from the outside of the motor-operated expansion valve to the space including the circuit board. For this reason, the structure of the motor-operated expansion valve described in Patent Document 1 cannot completely prevent outside air from flowing into the space including the circuit board. This type of problem can occur not only in motor-operated expansion valves, but also in motor-operated valves used for various purposes.

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an electric valve in which waterproofing of the space including the circuit board is ensured. [Means for solving the problem]

[0007] One aspect of the present invention is an electrically operated valve. The electrically operated valve includes a body and The motor-operated valve includes a valve element that moves toward and away from a valve hole in a body to open and close a valve portion, a rotor that drives the valve element in the opening and closing directions, a can that is a cylindrical member fixed to the body and encases the rotor, defining an internal space where fluid pressure acts and an external space where it does not act, a cylindrical case, a stator that is disposed within the case and coaxially inserted around the can, a circuit board disposed inside the case, power supply terminals connected to the circuit board, a connector forming portion having the power supply terminals inside, and a lid that forms a space containing the circuit board between the case and the lid. This motor-operated valve has a first seal between a first open end of the case and the lid, and a second seal between a second open end of the case and the body. The stator unit is assembled to the body by inserting the can into the case from the bottom side, and the second open end is partially covered by the side of the body to form the second seal. The space in the case where the bottom of the can is disposed is in communication with the space containing the circuit board. The connector forming portion is provided with a leak hole that allows pressure in the space containing the circuit board to leak to the outside.

[0008] According to this aspect, in a cylindrical case containing a circuit board, the first open end has a seal between it and the lid, and the second open end has a seal between it and the body. This prevents outside air from entering the space inside the case. In other words, it prevents moisture from entering the space containing the circuit board. [Effects of the Invention]

[0009] According to the present invention, waterproofing of the space including the circuit board in the motor-operated valve can be ensured. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing the structure of the motor-operated valve unit according to this embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing the structure of the motor-operated valve. [Figure 3] FIG. 3 is a diagram illustrating the structure of the stator unit. [Figure 4] FIG. 4 is a cross-sectional view showing how the case and the lid are fitted together. [Figure 5] FIG. 5 is a partial enlarged view showing the portion X in FIG. [Figure 6] FIG. 6 is a cross-sectional view showing a process of assembling the stator unit to the first body. [Figure 7] FIG. 7 is a cross-sectional view of the motor-operated valve according to the first modification. [Figure 8] FIG. 8 is a cross-sectional view of the motor-operated valve according to the second modification. [Figure 9] FIG. 9 is a cross-sectional view of the motor-operated valve according to the third modification. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For convenience, the following description may refer to the positional relationship of each structure based on the illustrated state. In the following embodiments and their modifications, substantially identical components will be designated by the same reference numerals, and their description will be omitted where appropriate.

[0012] [Embodiment] FIG. 1 is a cross-sectional view showing the structure of an electric valve unit U in an embodiment. The electric valve unit U includes an electric valve 1 and a piping body 2. The electric valve 1 is applied to a refrigeration cycle of an automotive air conditioner (not shown). This refrigeration cycle includes a compressor that compresses circulating refrigerant, a condenser that condenses the compressed refrigerant, an expansion valve that throttles and expands the condensed refrigerant and sends it out in the form of mist, and an evaporator that evaporates the mist of refrigerant and cools the air in the vehicle cabin using the latent heat of evaporation. The electric valve 1 functions as an expansion valve for the refrigeration cycle.

[0013] The motor-operated valve 1 is constructed by assembling a valve main body 200 to a motor unit 300. The valve main body 200 has a body 220 that houses a valve portion 212. The body 220 functions as a "valve body." The body 220 is constructed by assembling a cylindrical first body 240 and a cylindrical second body 260 coaxially.

[0014] The first body 240 has a stepped cylindrical shape whose outer diameter tapers in stages downward. A circular hole-shaped recessed fitting portion 241 is provided in the lower part of the first body 240. The second body 260 has a bottomed cylindrical shape, and its upper part is press-fitted into the recessed fitting portion 241. A valve hole 266 is provided so as to axially penetrate the bottom of the second body 260, and a valve seat 268 is formed at the upper opening of the valve hole 266. An inlet port 262 is provided in a side part of the second body 260, and an outlet port 264 is provided in the lower part. A valve chamber 270 is formed inside the first body 240 and the second body 260. The inlet port 262 and the outlet port 264 are in communication via the valve chamber 270.

[0015] An inlet port 202 and an outlet port 204 are provided on the side of the piping body 2. A pipe extending from the condenser side is connected to the inlet port 202, and a pipe leading to the inlet of the evaporator is connected to the outlet port 204. The inlet port 202 communicates with an inlet port 262, and the outlet port 204 communicates with an outlet port 264. The inlet port 202 and the outlet port 204 communicate with each other via a passage 206 formed in the piping body 2.

[0016] Annular seal members 208, 210 are respectively interposed between the first body 240 and the piping body 2 and between the second body 260 and the piping body 2. This configuration prevents fluid leakage through the clearance between the first body 240 and the piping body 2 and the clearance between the second body 260 and the piping body 2.

[0017] FIG. 2 is a cross-sectional view showing the motor-operated valve 1. As shown in FIG. A guide member 242 is erected at the upper center of the first body 240. The guide member 242 is a machined product made of a metal material, and a male thread portion 244 is formed on the outer peripheral surface of the axial center of the guide member 242. The lower end of the guide member 242 has a large diameter, and this large diameter portion 245 is coaxially fixed to the upper center of the first body 240. A shaft 246 extending from the rotor 320 of the motor unit 300 is inserted into the inside of the first body 240. The lower end of the shaft 246 also serves as a valve element 214 that constitutes the valve portion 212. The valve element 214 moves toward and away from a valve seat 268, thereby adjusting the opening degree of the valve portion 212. The guide member 242 supports the shaft 246 axially slidably with its inner peripheral surface, and rotatably supports the rotary shaft 326 of the rotor 320 with its outer peripheral surface.

[0018] Inside the valve chamber 270, an E-ring 216 is fitted to the lower part of the shaft 246. A spring retainer 218 is provided above the E-ring 216. A spring retainer 222 is also provided below the guide member 242, and a spring 224 that urges the valve element 214 in the valve closing direction of the valve portion 212 is inserted coaxially with the valve element 214 between the two spring retainers 218, 222. In this embodiment, the lower end of the shaft 246 also serves as the valve element 214, so the spring 224 also urges the shaft 246 in the valve closing direction.

[0019] Next, the structure of the motor unit 300 will be described. The motor unit 300 is configured as a three-phase stepping motor including a rotor 320 and a stator 340. The motor unit 300 has a cylindrical can 302 with a bottom, with the rotor 320 disposed inside the can 302 and the stator 340 disposed outside the can 302. The can 302 is a cylindrical member with a bottom that covers the space in which the valve element 214 and its drive mechanism are disposed and contains the rotor 320, and defines an inner pressure space (internal space) where the refrigerant pressure acts and an outer non-pressure space (external space) where the refrigerant pressure does not act. The open end 304 of the can 302 is fixed to the first body 240.

[0020] The stator 340 includes a laminated core 342 and a bobbin 344. The laminated core 342 is configured by laminating plate-shaped cores in the axial direction. A coil 346 is wound around the bobbin 344. The coil 346 and the bobbin 344 around which the coil 346 is wound are collectively referred to as a "coil unit 345." The coil unit 345 is assembled to the laminated core 342.

[0021] Stator 340 is provided integrally with a cylindrical case 400 of motor unit 300. Case 400 is obtained by injection molding of a corrosion-resistant resin material. Stator 340 is covered with molded resin obtained by this injection molding (also called "insert molding" or "mold molding"). Case 400 is made of this molded resin.

[0022] A lid portion 440 is fitted to the upper opening of the case 400. A circuit board 420 is disposed in a space S surrounded by the case 400 and the lid portion 440. The coil 346 is connected to the circuit board 420. A connector forming portion 402 is provided on the case 400. That is, the connector forming portion 402 is integrally molded with the case 400 using molded resin. The connector forming portion 402 has a power supply terminal 422 integrally formed therein and protects the power supply terminal 422 for supplying power from an external power source to the circuit board 420. Hereinafter, the stator 340, the case 400, the circuit board 420, the power supply terminal 422, the connector forming portion 402, and the lid portion 440 will be collectively referred to as a "stator unit 360."

[0023] The rotor 320 includes a cylindrical rotor core 322 and a magnet 324 provided along the outer periphery of the rotor core 322. The rotor core 322 is attached to a rotating shaft 326. The magnet 324 is magnetized with multiple poles in the circumferential direction.

[0024] The rotating shaft 326 is a machined product made of a metal material. The rotating shaft 326 is obtained by integrally molding the metal material into a cylindrical shape with a bottom. The rotating shaft 326 is fitted onto the guide member 242 with its open end facing downwards. A female thread portion 328 is formed on the inner peripheral surface of the rotating shaft 326, and meshes with a male thread portion 244 of the guide member 242. The screw feed mechanism using these thread portions converts the rotational motion of the rotor 320 into translational motion in the axial direction. The meshing point between the female thread portion 328 and the male thread portion 244 in the screw feed mechanism is called the "screw engagement portion."

[0025] The upper portion of the shaft 246 has a reduced diameter, and this reduced diameter portion penetrates the bottom of the rotary shaft 326. An annular stopper 330 is fixed to the tip of the reduced diameter portion. Meanwhile, a back spring 332 that urges the shaft 246 downward (in the valve closing direction) is interposed between the base end of the reduced diameter portion and the bottom of the rotary shaft 326. With this configuration, when the valve portion 212 is open, the stopper 330 engages with the bottom of the rotary shaft 326, and the shaft 246 moves integrally with the rotor 320. Meanwhile, when the valve portion 212 is closed, the back spring 332 is compressed by the reaction force that the valve element 214 receives from the valve seat 268. At this time, the elastic reaction force of the back spring 332 can press the valve element 214 against the valve seat 268, improving the seating performance (valve closing performance) of the valve element 214.

[0026] An annular seal member 203 is interposed between the first body 240 and the case 400. This configuration prevents outside air (moisture, etc.) from entering through the clearance between the first body 240 and the case 400.

[0027] FIG. 3 is a cross-sectional view showing the structure of the stator unit 360. As shown in FIG. 2, the case 400 and the cover 440 form a space S. In the space S, a circuit board 420 is provided.

[0028] The case 400 is provided with a leak hole 404 that communicates the inside of the connector forming portion 402 with the space S. The leak hole 404 will be described in detail later.

[0029] 4A and 4B are diagrams showing details of the assembly structure of the spigot fitting portion, where (A) is a cross-sectional view taken along the line AA in FIG. 3, and (B) is an exploded view of the spigot fitting portion in (A). In this embodiment, the open end 403 of the case 400 and the lid portion 440 are fitted together in an annular manner. Therefore, an annular abutment surface is formed between the upper surface of the open end 403 and the lower surface of the lid portion 440. A laser is irradiated along the abutment surface, thereby welding the case 400 and the lid portion 440 together. The spigot fitting structure between the case 400 and the lid portion 440 will be described in detail below.

[0030] 4(B), case 400 includes an open end 403 and two positioning protrusions 408 (which function as "positioning bodies"). Open end 403 is a cylindrical portion located at the top of case 400. Positioning protrusions 408 are provided inside open end 403 to position circuit board 420 relative to case 400.

[0031] 4(A) and 4(B), the lid portion 440 includes an abutting portion 442 having the above-described abutting surface, a protrusion 444 having a rectangular cross section, and a recess 446. The abutting portion 442 is provided on the bottom surface of the lid portion 440 along the entire periphery thereof. The protrusion 444 is provided in an annular shape along the inside of the abutting portion 442 on the bottom surface of the lid portion 440. Two recesses 446 are provided on the bottom surface of the lid portion 440, more inward than the protrusion 444.

[0032] Abutment portion 442 abuts along end face 406 of case 400 (the upper surface of open end 403). The outer peripheral surface of protrusion 444 faces the inner peripheral surface of open end 403. Protrusion 444 and open end 403 form a spigot fitting portion 448 (FIG. 4(A)).

[0033] As shown in FIG. 4A, a circuit board 420 is stored in a space S formed by the case 400 and the lid 440. Two positioning holes 424 are provided in the circuit board 420. The circuit board 420 is positioned relative to the case 400 by inserting two positioning protrusions 408 into the two positioning holes 424, respectively. The two positioning protrusions 408 are also fitted into two recesses 446 in the lid 440, respectively. This structure positions the lid 440 relative to the case 400. That is, the positioning protrusions 408 have the function of both positioning the circuit board 420 relative to the case 400 and positioning the lid 440 relative to the case 400.

[0034] Positioning protrusion 408 is press-fitted and fixed in recess 446. This positions lid 440 relative to case 400, and the gap between the outer peripheral surface of protrusion 444 and the inner peripheral surface of case 400 (gap at spigot fitting portion 448) is maintained uniform over the entire circumference.

[0035] Next, welding of the case 400 and the lid 440 will be described. FIG. 5 is an enlarged cross-sectional view of the X portion in FIG. 4(A).

[0036] As described above, the inner peripheral surface of the case 400 and the protrusion 444 of the lid portion 440 form a spigot fitting portion 448. The abutting portion 442 of the lid portion 440 abuts along the end face 406 of the case 400. The lid portion 440 is made of a laser-transmitting resin material, and the case 400 is made of a laser-absorbing resin material. When a laser is irradiated onto the abutting portion 442 from the lid portion 440 side, the laser passes through the lid portion 440 and is absorbed by the end face 406 of the case 400. Heat generated from the absorbed laser melts a portion of the end face 406 of the case 400. As shown in FIG. 5 , the molten resin material R accumulates in the gap of the spigot fitting portion 448 and bonds the outer peripheral surface of the protrusion 444 of the lid portion 440 to the open end 403 of the case 400 in a manner that bridges the two together.

[0037] In this embodiment, molten resin material R is poured into the gap of the spigot fitting portion 448, and the resin material R is fixed in a manner that bridges the outer peripheral surface of the protrusion 444 of the lid portion 440 and the open end 403 of the case 400. As a result, the lid portion 440 and the case 400 are welded not only at the abutment portion 442 but also at the spigot fitting portion 448, thereby improving the weldability. Hereinafter, the portion where the lid portion 440 and the case 400 are welded by the molten resin material R will be referred to as the "welded portion 460" or the "first seal portion."

[0038] 6A and 6B are cross-sectional views showing how the stator unit 360 is assembled to the first body 240. (A) shows the state during assembly, and (B) shows the state after assembly is completed. Prior to assembly, the circuit board 420 is disposed inside the case 400. Furthermore, as described in relation to Fig. 5, the case 400 and the lid portion 440 are welded together.

[0039] During assembly, can 302 is inserted into stator unit 360 from opening end 410, which is opposite opening end 403 of case 400. Then, assembly of stator unit 360 to first body 240 is completed in a state in which opening end 410 encloses opening end 304 of can 302 and seal member 203.

[0040] Of the open ends of case 400, open end 410 is assembled to first body 240 in a manner that seal member 203 abuts against its inner peripheral surface. Open end 403 is also welded to lid 440 by welded portion 460. That is, case 400 is sealed from the outside at two open ends 403, 410. This structure prevents the air outside case 400 from flowing into space S located inside case 400.

[0041] The connector forming portion 402 is provided with a leak hole 404. Prior to assembling the stator unit 360 to the first body 240, the case 400 and the lid portion 440 are welded together. Therefore, as the can 302 is inserted into the stator unit 360, the gas pressure in the space S increases. If this pressure is too high, there is a risk that the circuit board 420 and other components housed in the space S will be damaged. In this embodiment, the leak hole 404 allows the internal pressure of the space S to leak into the connector forming portion 402. With this configuration, even when the can 302 is inserted into the stator unit 360 and the stator unit 360 is assembled to the first body 240, the circuit board 420 and other components will not be damaged.

[0042] After the stator unit 360 is assembled to the first body 240, the temperature inside the space S changes when the motor-operated valve 1 is in operation. If the leak hole 404 does not exist and the case 400 is sealed, the internal pressure inside the space S changes in accordance with this temperature change. If this internal pressure increases, problems such as damage to the circuit board 420, rupture of the welded portion 460, deformation of the case 400 or the lid portion 400, and damage to the coil 346 (see FIG. 2) may occur. By providing the leak hole 404 and allowing the internal pressure of the space S to leak into the connector forming portion 402, damage to the circuit board 420 and the like can be prevented even when the motor-operated valve 1 is in operation.

[0043] The leakage of internal pressure from space S when motor-operated valve 1 is in operation will be described in more detail. Connector forming portion 402 is connected to an external connector (not shown). A harness is connected to terminals provided on the external connector. Therefore, pressure in space S leaks to the outside through leak hole 404 and the harness. In addition, a seal ring (not shown) is provided between connector forming portion 402 and the external connector. With this structure, leak hole 404 communicates with the inside of the harness, but is sealed from the air outside motor-operated valve 1. Because space S does not communicate with the periphery of motor-operated valve 1, the inflow of outside air into space S is suppressed even if leak hole 404 is provided.

[0044] As described above, according to this embodiment, the case 400 is molded around the stator 340 using mold resin. That is, the case 400 is obtained by a single molding process. Furthermore, in the cylindrical case 400, the open end 403 is welded to the lid 440, and the open end 410 has the seal member 203 (second seal portion) between it and the first body 240. The provision of the first seal portion and the second seal portion makes it possible to prevent the inflow of air into the space S. That is, it is possible to ensure waterproofing for the space S containing the circuit board 420.

[0045] According to this embodiment, the connector forming portion 402 is formed integrally with the case 400 through a single molding process. This reduces the number of parts in the motor-operated valve 1. Fewer parts means fewer places that need to be sealed between parts. This prevents outside air from entering the motor-operated valve 1.

[0046] 7 to 9 are cross-sectional views of motor-operated valves according to modifications of this embodiment. Fig. 7 shows a motor-operated valve 101 according to Modification 1, Fig. 8 shows a motor-operated valve 102 according to Modification 2, and Fig. 9 shows a motor-operated valve 103 according to Modification 3.

[0047] As shown in FIG. 7 , the motor-operated valve 101 according to the first modification differs from the motor-operated valve 1 according to the embodiment in the shape of the case 500. The case 500 includes an inner molded portion 510 and a cylindrical outer molded portion 520. The stator 340 is covered by the inner molded portion 510 by molding. The inner molded portion 510, which is made of a molded resin, is covered by the outer molded portion 520 by molding. In other words, the outer molded portion 520 is made of a molded resin. The connector forming portion 402 is integrally molded with the outer molded portion 520.

[0048] In the first modification, the open end 523 of the outer mold part 520 and the lid part 440 are welded together to form a welded part 560. A seal member 203 is provided between the open end 530 of the outer mold part 520 and the first body 240. Meanwhile, the inner mold part 510 is completely housed inside the outer mold part 520. That is, the inner mold part 510 is not exposed to the outside of the motor-operated valve 101. The seal structure at the two open ends 523, 530 prevents outside air from flowing into the outer mold part 520. Furthermore, the resin-contacting part (between the outer mold part 520 and the inner mold part 510) that is connected to the space S is completely isolated from the outside of the motor-operated valve 101. Therefore, in the first modification, the inflow of outside air into the space S can be prevented.

[0049] The motor-operated valve 101 of the first modification can also prevent outside air from entering the space S, ensuring waterproofing of the space S. On the other hand, from the viewpoint of sealing performance, the motor-operated valve 1 according to the embodiment, which has a smaller number of parts, is more preferable.

[0050] As shown in FIG. 8 , the motor-operated valve 102 according to the second modification differs from the motor-operated valve 1 according to the first embodiment in the shape of the case 600. The case 600 includes an inner mold portion 610 and a cylindrical outer mold portion 620. The stator 340 is covered by the inner mold portion 610 by molding. The outer mold portion 620 is obtained by molding in a separate process from the inner mold portion 610. In other words, the outer mold portion 620 is made of a mold resin. The connector forming portion 402 is molded integrally with the outer mold portion 620.

[0051] The stator 340 covered with the inner mold part 610 and the circuit board 420 are stored inside the outer mold part 620. Thereafter, a lid part 440 is provided on the open end part 523 of the outer mold part 620, thereby obtaining the stator unit 360.

[0052] In the second modification, the opening end 623 and the lid portion 440 are also welded to form a welded portion 660. A seal member 203 is provided between the opening end 630 of the outer mold portion 620 and the first body 240. Meanwhile, the inner mold portion 610 is completely housed inside the outer mold portion 620. That is, the inner mold portion 610 is not exposed to the outside of the motor-operated valve 102. The seal structure at the two opening ends 623, 630 prevents outside air from flowing into the outer mold portion 620. Furthermore, the space between the outer mold portion 620 and the inner mold portion 610 is completely isolated from the outside of the motor-operated valve 102. Therefore, in the second modification, outside air can be prevented from flowing into the space S.

[0053] In the motor-operated valve 102, the inner mold section 610 and the outer mold section 620 are molded in separate processes and are assembled together during the assembly process of the case 600. Therefore, it is necessary to align the dimensions between the inner mold section 610 and the outer mold section 620. In the motor-operated valve 101 of Modification 1 (see FIG. 7), the alignment between the inner mold section 510 and the outer mold section 520 can be easily performed using the mold used when molding the outer mold section 520. The motor-operated valve 101 of Modification 1 is more preferable than the motor-operated valve 102 of Modification 2 because it is easier to align the stator 340 with respect to the case 500.

[0054] As shown in FIG. 9, the motor-operated valve 103 according to the third modification differs from the motor-operated valve 1 according to the first embodiment in the shape of the case 700. In the motor-operated valve 1 of the third modification, the stator 340 is not covered with molding resin. The case 700 is obtained by molding, similar to the outer mold part 620 (see FIG. 8) in the second modification. The connector forming part 402 is molded integrally with the case 700.

[0055] Stator 340 and circuit board 420 are housed inside case 700. Thereafter, lid 440 is provided on open end 703 of case 700, thereby obtaining stator unit 360.

[0056] In the third modification, opening end 703 and lid portion 440 are also welded to form welded portion 760. Furthermore, seal member 203 is provided between opening end 710 of case 700 and first body 240. The seal structure at the two opening ends 703, 710 prevents outside air from flowing into case 700. Therefore, in the third modification, outside air can also be prevented from flowing into space S.

[0057] Because the motor-operated valve 103 directly houses the stator 340 in the case 700, it can be manufactured more easily than the motor-operated valve 101 (see FIG. 7) or the motor-operated valve 102 (see FIG. 8), in which the stator 340 is covered with a molded resin. On the other hand, protecting the stator 340 (coil 346 in FIG. 2) with a molded resin makes it easier to release heat from the coil 346, thereby reducing the resistance value of the coil 346. In this respect, the motor-operated valve 101 or the motor-operated valve 102 is preferable to the motor-operated valve 103.

[0058] Although the preferred embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to this specific embodiment, and various modifications are possible within the scope of the technical concept of the present invention.

[0059] In the above embodiment, a weld is used as the first seal and a seal ring is used as the second seal. In a modified example, a seal ring may be used as the first seal. For example, a seal ring may be provided between the protrusion of the lid and the inner peripheral surface of the case.

[0060] In the above embodiment, a second seal portion is provided between the inner peripheral surface of the case and the outer peripheral surface of the first body. In a modified example, a seal ring may be provided between the inner peripheral surface of the case and the outer peripheral surface of the can to serve as the second seal portion. However, a configuration in which the open end of the can is located further inward than the second seal portion on the case is more preferable because it eliminates the risk of corrosion of the weld between the open end of the can and the body due to the outside air.

[0061] In the above embodiment, the electrically operated valve has been described in which the valve element is detachable from the valve seat and the valve portion is fully closed in the closed state. In a modified example, the valve element may be inserted and removed from the valve hole like a so-called spool valve, and a small amount of fluid leakage may be permitted in the closed state.

[0062] In the above embodiment, the motor-operated valve is configured as a motor-operated expansion valve, but it may also be configured as an on-off valve or a flow control valve that does not have an expansion function.

[0063] In the above embodiment, the valve body and the shaft are integrally molded. However, the modified example is not limited to this, and the valve body and the shaft may be separate members that are displaceable as a unit. In this case, the valve body and the shaft may be structurally integrated. Alternatively, the valve body and the shaft may be displaceable as a unit and also displaceable relative to each other. For example, as in the motor-operated valve described in JP 2016-205584 A, the valve body and the shaft may be displaceable as a unit when the valve is open, and may be displaceable relative to each other when the valve is closed.

[0064] In the above embodiment, the first body 240 and the second body 260 are used as the bodies of the motor-operated valve, and these two bodies are disposed in the piping body 2 to form the motor-operated valve unit U. In a modified example, the first body 240, the second body 260, and the piping body 2 may be collectively used as the body of the motor-operated valve.

[0065] The present invention is not limited to the above-described embodiments and modifications, and the components can be modified without departing from the spirit of the invention. Various inventions can be formed by appropriately combining multiple components disclosed in the above-described embodiments and modifications. Furthermore, some components can be omitted from all the components shown in the above-described embodiments and modifications. [Explanation of symbols]

[0066] 1 Motor-operated valve, 2 Piping body, 101 Motor-operated valve, 102 Motor-operated valve, 103 Motor-operated valve, 200 Valve body, 202 Inlet port, 203 Seal member, 204 Outlet port, 206 Passage, 208 Seal member, 212 Valve portion, 214 Valve body, 216 E-ring, 218 Spring retainer, 220 Body, 222 Spring retainer, 224 Spring, 240 First body, 241 Concave fitting portion, 242 Guide member, 244 Male thread portion, 245 Large diameter portion, 246 Shaft, 260 Second body, 262 Inlet port, 264 Outlet port, 266 Valve hole, 268 Valve seat, 270 Valve chamber, 300 Motor unit, 302 Can, 304 Open end, 320 Rotor, 322 Rotor core, 324 Magnet, 326, rotating shaft, 328, female thread portion, 330, stopper, 332, back spring, 340, stator, 342, laminated core, 344, bobbin, 345, coil unit, 346, coil, 360, stator unit, 400, case, 402, connector forming portion, 403, opening end, 404, leak hole, 406, end face, 408, positioning protrusion, 410, opening end, 420, circuit board, 422, power supply terminal, 424, positioning hole, 440, cover portion, 442, abutment portion, 444, protrusion, 446, recess, 448, spigot fitting portion, 460, welded portion, 500, case, 510, inner mold portion, 520, outer mold portion, 523, opening end, 530, opening end, 560, welded portion, 600 Case, 610 inner mold part, 620 outer mold part, 623 opening end, 630 opening end, 660 welding part, 700 case, 703 opening end, 710 opening end, 760 welding part, R resin material, S space, U electric valve unit.

Claims

[Claim 1] Body and a valve element that opens and closes a valve portion by moving toward and away from a valve hole provided in the body; a rotor for driving the valve body in the opening and closing direction of the valve portion; a can, which is a cylindrical member with a bottom and an open end fixed to the body and which contains the rotor, and which defines an internal space on which fluid pressure acts and an external space on which fluid pressure does not act; a stator unit including a cylindrical case, a stator disposed in the case and coaxially inserted around the can, a circuit board disposed inside the case, a power supply terminal connected to the circuit board, a connector forming portion having the power supply terminal therein, and a lid portion forming a space between the case and the stator unit and containing the circuit board; Equipped with a first seal portion between the first open end of the case and the lid portion; a second seal portion between the second open end of the case and the body; the stator unit has an opening on the second open end side of the case for receiving the can so that the can can be inserted into the case from the bottom side thereof when assembled to the body, the circuit board is disposed so as to cross the axis of the can in the case on the first open end side, and the second open end is partially covered with a side surface of the body to realize the second seal portion; a space in the case where the bottom of the can is disposed communicates with a space that contains the circuit board; the connector forming portion is provided with a leak hole that allows pressure in a space that contains the circuit board to leak to the outside, The motor-operated valve is characterized in that the leak hole opens closer to the can than the circuit board in the axial direction of the can.

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