Motor-operated valve

Abstract

To provide a motor-operated valve which moves a valve element in an inside of a body part by action of driving force generated by electric power in a drive part and can improve waterproofness with respect to an inside thereof.SOLUTION: An electric expansion valve 1 includes a body part 40, a drive motor 10, a holding member 27, and a casing 54. The body part 40 has a refrigerant flow passage 45 through which fluid flows in an inside thereof. The holding member 27 is attached to an attachment part 46 formed on one surface of the body part 40. The holding member 27 guides a movement direction of a valve element 33 toward an inside of the refrigerant flow passage 45, and positions the valve element 33 and the drive motor 10. The casing 54 is attached to the body part 40 so as to cover the holding member 27 and the drive motor 10 on one surface side of the body part 40. In the vicinity of the attachment part 46 in the body part 40, a step part 47 formed by displacing one surface of the body part 40 in a vertical direction is formed at a position adjacent in an inner side of a contact portion with the casing 54.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an electrically operated valve that moves a valve element inside a main body by the action of a driving force generated in a driving unit by electric power. [Background technology]

[0002] Conventionally, in motor-operated valves, if moisture enters the inside of the casing, it is assumed that the operation of the internal mechanisms such as the motor will be affected, so technologies have been developed to prevent moisture from entering the interior. For example, the technology described in Patent Document 1 is known as a technology for preventing moisture from entering the interior.

[0003] The technology described in Patent Document 1 improves the waterproofing of the inside of the electric valve by placing an annular sealing member between a cylindrical portion formed integrally with the stator that constitutes the motor and a stator-opposing portion formed in the main body of the valve. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7000622 Summary of the Invention [Problem to be solved by the invention]

[0005] In the technology of Patent Document 1, the waterproofing of the inside of the motor-operated valve depends largely on the performance of the sealing member, and it is expected that moisture will penetrate into the inside of the motor-operated valve if the sealing member deteriorates.

[0006] In particular, in the configuration described in Patent Document 1, the seal member is sandwiched between the upper surface of the main body and the lower end of the tubular portion, and the contact surface between the second body sleeve, which corresponds to the retaining member, and the main body is located around it. In other words, if moisture penetrates due to deterioration of the seal member, it is thought that moisture will penetrate through the gap formed between the second body sleeve and the main body. Therefore, there is a need to develop a different type of design to improve the waterproofing of the inside of the motor-operated valve.

[0007] In view of the above, the present disclosure aims to provide an electric valve that moves a valve body inside a main body by the action of a driving force generated in a drive unit by electricity, and that has improved waterproofing for the interior. [Means for solving the problem]

[0008] The motor-operated valve according to one aspect of the present disclosure includes a main body (40), a drive unit (10), a retaining member (27), and a casing (54). The main body has a flow path (45) therein through which a fluid flows. The drive unit uses electricity to generate a drive force that moves a valve element (33) that adjusts the flow rate of the fluid through the flow path. The hold member is attached to a mounting portion (46) formed on one surface of the main body. The holding member guides the movement of the valve element toward the inside of the flow path and positions the valve element and the drive unit. The casing is attached to the main body on one side of the main body so as to cover the hold member and the drive unit. A step portion (47) is formed around the mounting portion of the main body, displacing one surface of the main body in the vertical direction, at a position adjacent to and inside the contact portion with the casing.

[0009] According to the electric valve, the drive unit and the retaining member are housed in the internal space formed by the casing and the main body, and a step portion located around the mounting portion is arranged between the outside of the electric valve and the internal space.

[0010] Since the gap formed between the casing and the main body is located between the outside and the internal space of the motor-operated valve, the provision of a step portion allows the length of the gap to be increased according to the amount of vertical displacement. As a result, by forming the step portion, the motor-operated valve can more reliably prevent moisture from entering through the gap between the casing and the main body.

[0011] Furthermore, by providing a step between the exterior of the motor-operated valve and the internal space, the head of water required when water infiltrates between the exterior of the motor-operated valve and the internal space through the gap between the casing and the main body can be increased according to the amount of vertical displacement of the step. As a result, by forming the step, the motor-operated valve can suppress water infiltration through the gap between the casing and the main body from the perspective of the positional head of water.

[0012] The symbols in parentheses for each means described in this section and in the claims indicate the correspondence with the specific means described in the embodiments to be described later. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic configuration diagram of a motor-operated valve according to a first embodiment. [Figure 2] FIG. 3 is an enlarged cross-sectional view showing a joint portion between a casing and a main body in the first embodiment. [Figure 3] FIG. 10 is an external view of a flow path box configured as a motor-operated valve according to a second embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing the configuration of a motor-operated valve according to a third embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing the configuration of a motor-operated valve according to a fourth embodiment. [Figure 6] FIG. 10 is a cross-sectional view showing the configuration of a motor-operated valve according to a fifth embodiment. [Figure 7] FIG. 10 is a cross-sectional view showing the configuration of a motor-operated valve according to a sixth embodiment. [Figure 8] FIG. 13 is a cross-sectional view showing the configuration of a motor-operated valve according to a seventh embodiment. [Figure 9]FIG. 13 is a cross-sectional view showing the configuration of a motor-operated valve according to an eighth embodiment. [Figure 10] FIG. 10 is an explanatory diagram showing a modified example of the motor-operated valve according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, several embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment may be assigned the same reference numerals, and duplicate descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other previously described embodiments may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically specified as being combinable in each embodiment, it is also possible to partially combine embodiments even if not specified, as long as there is no particular problem with the combination.

[0015] (First embodiment) A first embodiment of the present disclosure will be described with reference to the drawings. The motor-operated valve according to the present disclosure is disposed in a fluid circuit such as a refrigerant circuit or a heat medium circuit, and adjusts the flow rate of the fluid by operating a valve element with an electrically generated driving force. The motor-operated valve according to the first embodiment is applied to a refrigerant circuit constituting the refrigeration cycle of an air conditioner, and is used as an electric expansion valve 1 that reduces the pressure and expands the refrigerant. The electric expansion valve 1 adjusts the flow rate of the refrigerant and reduces the pressure of the refrigerant by transmitting driving force generated by electricity from a drive motor 10 as a driving source and moving the valve element.

[0016] Although not shown in the drawings, in the following embodiments, the refrigeration cycle has at least a compressor, a condenser, and an evaporator in addition to the electric expansion valve 1. The electric expansion valve 1 is disposed between the condenser and the evaporator in the refrigeration cycle, and reduces the pressure of the refrigerant flowing out from the condenser so that it flows toward the evaporator. The vehicle air conditioner also has an air conditioning control device, and the amount of pressure reduction (i.e., the throttle opening) in the electric expansion valve 1 is controlled by a control signal from the air conditioning control device.

[0017] First, the configuration of an electric expansion valve 1 according to the first embodiment will be described with reference to Figures 1 and 2. As shown in Figure 1, the electric expansion valve 1 according to the first embodiment has a main body 40 in which a valve chamber 41 and the like are formed, and an accommodating section 50 that accommodates a drive motor 10 and the like as a drive source. The drive motor 10 corresponds to an example of a drive section.

[0018] The electric expansion valve 1 is disposed in a vertical position in the vehicle. The vertical position means that the axial direction of the valve body 30 is approximately parallel to the vertical direction of the vehicle, and the accommodation section 50 is disposed above the main body 40, which can also be called the standard position.

[0019] A drive motor 10 is disposed inside the accommodation section 50. The drive motor 10 has a rotor 11, a shaft 12, and a stator 13, and is configured as a three-phase motor. The shaft 12 is journaled inside a motor case 53 that constitutes the accommodation section 50, and rotates integrally with the rotor 11. The motor case 53 is joined to the top surface of the main body section 40, and accommodates the rotor 11 and shaft 12 of the drive motor 10, as well as the reduction mechanism section 20 inside. The inside of the motor case 53 constitutes a mechanism accommodation section 51 of the accommodation section 50 that accommodates the drive mechanism.

[0020] The stator 13 constituting the drive motor 10 is disposed inside the casing 54 so as to surround the rotor 11 from the outside via the motor case 53, and is fixed between the motor case 53 and the casing 54. The stator 13 is cylindrical and has a stator coil. The stator 13 generates a rotating magnetic field inside the stator core by passing a three-phase AC current (U phase, V phase, W phase) through the stator coil via the drive circuit unit 60.

[0021] Rotor 11 is arranged inside motor case 53 so as to be located inside cylindrical stator 13. Rotor 11 has multiple pairs of magnets, each consisting of an N pole and an S pole, arranged along the circumferential direction.

[0022] 1, the housing 50 has a casing 54. The casing 54 is joined to an attachment portion 46 formed on one side of the main body 40, i.e., the upper surface, so as to house the motor case 53 and the stator 13 therein. The casing 54 is made of a thermoplastic resin (e.g., polyphenylene sulfide), and is attached to the main body 40 so as to cover the drive motor 10 and the like.

[0023] A cylindrical portion 54a that communicates with the interior of the casing 54 is formed at the bottom of the casing 54. The casing 54 is attached to the attachment portion 46 formed on the top surface of the main body 40 via the cylindrical portion 54a.

[0024] Furthermore, a drive circuit section 60 and a position sensor 61 are arranged outside the motor case 53 and inside the casing 54. The part of the inside of the casing 54 that is outside the motor case 53 constitutes a circuit accommodating section 52 that accommodates the drive circuit section 60 and the like. In other words, the accommodating section 50 formed inside the casing 54 is divided by the motor case 53 into a mechanism accommodating section 51 and a circuit accommodating section 52.

[0025] As described above, the reduction mechanism 20 is disposed inside the motor case 53 together with the rotor 11 and the shaft 12. The reduction mechanism 20 is disposed below the rotor 11 and is a mechanism that reduces the angular velocity output by the rotor 11 at a predetermined reduction ratio and outputs the reduced angular velocity.

[0026] The speed reduction mechanism 20 according to the first embodiment is configured by a planetary gear mechanism and has a sun gear 21, a plurality of planet gears 22, a fixed gear 23, and a carrier 24. The sun gear 21 is attached to the lower end of the shaft 12 of the drive motor 10, and rotates inside the fixed gear 23, which is a ring gear, in synchronization with the rotation of the rotor 11. The fixed gear 23 is fixed to the inside of the motor case 53, and a predetermined number of internal teeth are formed on the inside of the ring-shaped fixed gear 23.

[0027] The carrier 24 rotatably supports a plurality of (three in this embodiment) planetary gears 22. Each planetary gear 22 is positioned between the external teeth of the sun gear 21 and the internal teeth of the fixed gear 23, and is supported by the carrier 24 so as to mesh with the external teeth of the sun gear 21 and the internal teeth of the fixed gear 23, respectively.

[0028] An output shaft 24a is formed on the lower surface of the carrier 24. As shown in FIG. 1, the output shaft 24a is supported by an output bearing 25 disposed on the upper surface of the main body 40. Therefore, the carrier 24 is rotatably supported inside the motor case 53. With this configuration, in the reduction mechanism 20, the rotation of the rotor 11 and the sun gear 21 is reduced at a predetermined reduction ratio and transmitted to the carrier 24, which rotates around the output shaft 24a.

[0029] An engagement groove is formed at the lower end of the output shaft 24a. A protruding piece formed at the upper end of the valve body 30 engages with the engagement groove of the output shaft 24a. Therefore, the rotation of the output shaft 24a is transmitted to the valve body 30 via the engagement groove and the protruding piece.

[0030] 1, a shaft case 26 is attached to the upper surface of the main body 40. The shaft case 26 is attached to an attachment portion 46 formed above the main body 40 via a retaining member 27, and has a communication hole 26a through which the valve main body 30 is inserted.

[0031] The retaining member 27 is made of stainless steel and is attached to a mounting portion 46 formed on the main body 40 with the shaft case 26 held inside. The mounting portion 46 is open on the top surface of the main body 40 so as to communicate with the valve chamber 41. Therefore, the retaining member 27 holds the shaft case 26 so that the communication hole 26a is coaxial with the shaft 12 and output shaft 24a of the drive motor 10. As a result, the movement direction of the valve main body 30 is determined by the communication hole 26a so that it moves coaxially with the shaft 12 and output shaft 24a. Note that stainless steel corresponds to the second metal.

[0032] In addition, a refrigerant sealing member 28 is disposed on the outer peripheral surface of the holding member 27. The refrigerant sealing member 28 is a member for sealing the flow of fluid including refrigerant between the inner surface of the mounting portion 46 and the outer surface of the holding member 27, and may be, for example, an O-ring made of ethylene propylene diene rubber. This enables the electric expansion valve 1 to suppress refrigerant leakage between the holding member 27 and the surface of the mounting portion 46.

[0033] In the electric expansion valve 1 of the first embodiment, the main body 40 is formed from a cast material (e.g., AC4C) using an Al-Si-Mg aluminum alloy, and has a valve chamber 41, a valve seat 42, a first inlet / outlet 43, and a second inlet / outlet 44. The cast material using the aluminum alloy corresponds to the cast material containing the first metal. The valve chamber 41 is the portion of the main body 40 through which the refrigerant of the refrigeration cycle flows, and also forms a space through which the valve element 33 of the valve body 30 moves.

[0034] An attachment portion 46 is formed on the upper surface of the main body 40. The attachment portion 46 communicates with the upper portion of the valve chamber 41 and is adapted to attach the shaft case 26 and the retaining member 27. An inner step 47a is formed on the opening edge of the attachment portion 46 formed on the upper surface of the main body 40.

[0035] The inner step portion 47a is formed by displacing the upper surface of the main body portion 40 vertically upward. In other words, the inner step portion 47a is formed in a cylindrical shape that protrudes upward at the opening edge of the mounting portion 46. The inner step portion 47a is disposed adjacent to the cylindrical portion 54a of the casing 54 in the inward direction of the electric expansion valve 1.

[0036] 1 and 2, a valve seat 42 is formed inside the valve chamber 41. As described above, the shaft case 26 and the retaining member 27 are attached to the attachment portion 46 located above the valve chamber 41, so that the valve chamber 41 communicates with the mechanism accommodating portion 51 of the accommodating portion 50 via the communication hole 26a.

[0037] Furthermore, a first inlet / outlet 43 and a second inlet / outlet 44 are connected to the valve chamber 41 as part of a refrigerant flow path 45 formed inside the main body 40. The refrigerant flow path 45 corresponds to an example of a flow path. The first inlet / outlet 43 is connected to the outlet side of a condenser in the refrigeration cycle. The first inlet / outlet 43 is connected so as to be located upstream of the valve seat 42 with respect to the flow of refrigerant in the valve chamber 41. A refrigerant pipe extending from the outlet of a condenser in the refrigeration cycle of the vehicle air conditioner is joined to the end of the first inlet / outlet 43 located outside the main body 40, for example by brazing.

[0038] On the other hand, the second inlet / outlet 44 is connected to the inlet side of the evaporator in the refrigeration cycle. The second inlet / outlet 44 constitutes a part of a refrigerant flow path 45 connecting the valve chamber 41 and the inlet side of the evaporator. The end of the second inlet / outlet 44 on the valve chamber 41 side is connected to be located downstream of the valve seat 42 with respect to the refrigerant flow in the valve chamber 41. Furthermore, a refrigerant pipe extending to the inlet of the evaporator in the refrigeration cycle of the vehicle air conditioner is joined, for example by brazing, to the end of the second inlet / outlet 44 located outside the main body 40. Therefore, in the electric expansion valve 1, when the valve element 33 moves away from the valve seat 42 in the valve chamber 41, the refrigerant flows from the first inlet / outlet 43 to the second inlet / outlet 44 and is decompressed and expanded.

[0039] As shown in Fig. 2, the valve body 30 according to the first embodiment is formed in a rod shape, integrally including a screw shaft 31, a valve stem 32, and a valve element 33 in this order. A protruding piece that engages with the aforementioned engagement groove is formed on the end of the valve body 30 on the screw shaft 31 side. A male thread is formed on the outer circumferential surface of the screw shaft 31 of the valve body 30. The male thread of the screw shaft 31 is threadedly engaged with a female thread portion 26b formed in a part of the communication hole 26a.

[0040] The male thread of the screw shaft 31 that constitutes the valve body 30 and the female thread portion 26b in the communication hole 26a form a screw mechanism 36. The screw mechanism 36 converts the rotational movement of the valve body 30 transmitted via the output shaft 24a into a forward and backward movement along the axial direction inside the communication hole 26a.

[0041] A valve stem 32 is formed on the end of the screw shaft 31 of the valve body 30 opposite the protruding piece. The valve stem 32 transmits the forward and backward movement converted by the screw mechanism 36 to the valve element 33 located inside the valve chamber 41. In addition, the valve stem 32 cooperates with the communication hole 26a of the shaft case 26 to guide the movement of the valve element 33 in the valve body 30 in the forward and backward direction relative to the valve seat 42.

[0042] A valve element 33 is disposed at the end of the valve rod 32. The valve element 33 comes into contact with and moves away from a valve seat 42 formed inside the valve chamber 41 as the valve body 30 moves back and forth. In this way, the valve element 33 opens and closes an opening in the valve seat 42. By adjusting the opening of the valve seat 42 with the valve element 33, the amount of pressure reduction in the electric expansion valve 1 and the flow rate of refrigerant flowing through the electric expansion valve 1 can be adjusted.

[0043] A coil spring 34 is disposed between the lower end of the shaft case 26, which forms the upper surface of the valve chamber 41, and the valve element 33 of the valve body 30. The coil spring 34 is attached in a state in which the valve stem 32 of the valve body 30 is inserted through the coil spring 34. The coil spring 34 biases the valve body 30 in a direction that brings the valve element 33 closer to the valve seat 42.

[0044] As a result, the biasing force of the coil spring 34 can cancel backlash in the screw shaft 31 of the valve body 30 and the female screw portion 26b of the shaft case 26, making the flow rate characteristics of the refrigerant in the electric expansion valve 1 uniform.

[0045] 2, a sliding member 35 is attached between the lower end of the coil spring 34 and the upper part of the valve body 33. The sliding member 35 is formed in the shape of an annular flat plate, and slides between the coil spring 34 and the valve body 30 when the valve body 30 is rotated by the screw mechanism 36. This allows the sliding member 35 to reduce torque loss that occurs between the coil spring 34 and the housing portion 50.

[0046] The electric expansion valve 1 according to the first embodiment is configured as a valve unit 70 that integrates the drive motor 10, the speed reduction mechanism 20, the valve body 30, etc. In other words, the electric expansion valve 1 achieves the configuration shown in Fig. 1 by attaching the valve unit 70 to the attachment portion 46 of the main body 40. Therefore, the valve unit 70 is a unit formed by assembling the drive motor 10, the speed reduction mechanism 20, the shaft case 26, the holding member 27, the valve body 30, the casing 54, etc.

[0047] Next, the operation of the electric expansion valve 1 according to the first embodiment configured as described above will be described with reference to the drawings. In the electric expansion valve 1 according to the first embodiment, when the drive motor 10 rotates the rotor 11 using electric power, the sun gear 21 of the speed reduction mechanism 20 rotates. In the speed reduction mechanism 20, the rotational force of the rotor 11 is reduced at a predetermined reduction ratio by the operation of the sun gear 21, the plurality of planetary gears 22, and the fixed gear 23, and is transmitted to the valve body 30 via the output shaft 24a.

[0048] When the valve body 30 rotates due to the rotational force transmitted from the output shaft 24a, the rotational movement of the valve body 30 is converted into an axial movement of the valve body 30 back and forth by the screw shaft 31 of the valve body 30 and the female screw portion 26b of the shaft case 26.

[0049] Because the screw mechanism 36 converts the rotational movement of the valve body 30 into an advancing and retreating movement, the axial movement of the valve body 30 can be changed by switching the rotational direction of the valve body 30. For example, when the rotational direction of the rotor 11 is rotated in a predetermined direction, the valve element 33 can be moved closer to the valve seat 42. In this case, when the rotational direction of the rotor 11 is rotated in the opposite direction to the predetermined direction, the valve element 33 can be moved away from the valve seat 42.

[0050] As a result, the valve element 33 arranged at the end of the valve body 30 moves closer to or away from the valve seat 42 within the valve chamber 41, thereby adjusting the degree of opening of the valve seat 42. By operating each component in this way, the electric expansion valve 1 according to the first embodiment can adjust the amount of pressure reduction in the electric expansion valve 1 and the flow rate of refrigerant passing through the electric expansion valve 1.

[0051] Here, the infiltration of water into the interior of the electric expansion valve 1 according to the first embodiment will be considered with reference to the drawings. Conventionally, there has been concern in electric expansion valves that water may infiltrate through gaps in the casing or main body, affecting the internal mechanism of the electric expansion valve.

[0052] For this reason, in the electric expansion valve 1 according to the first embodiment, a cylindrical inner step 47a is provided around the mounting portion 46 on the upper surface of the main body 40. A possible route for moisture to penetrate from the outside of the electric expansion valve 1 to the internal mechanism is a gap formed between the surface of the main body 40 and the surface of the casing 54.

[0053] In the electric expansion valve 1 according to the first embodiment, by forming the inner step portion 47a around the mounting portion 46, the moisture infiltration path to the internal mechanism can be made longer than when the upper surface of the main body portion 40 is configured flat, and pressure loss in the infiltration path can be improved. That is, the electric expansion valve 1 according to the first embodiment improves pressure loss in the moisture infiltration path formed between the main body portion 40 and the casing 54 by forming the inner step portion 47a, and can prevent moisture from infiltrating the internal mechanism of the electric expansion valve 1.

[0054] Furthermore, in the first embodiment, the inner step portion 47a is configured by displacing the upper surface of the main body portion 40 so that it protrudes vertically upward. Therefore, in the electric expansion valve 1 according to the first embodiment, the head of water required for moisture to penetrate to the internal mechanism can be increased by the amount of vertical movement of the inner step portion 47a. According to the electric expansion valve 1 according to the first embodiment, by providing the inner step portion 47a, the head of water required for moisture to penetrate into the electric expansion valve 1 can be increased, and moisture penetration into the electric expansion valve 1 can be suppressed.

[0055] Furthermore, in the electric expansion valve 1 according to the first embodiment, the main body 40 is made of a cast material using an aluminum alloy, and the holding member 27 is made of stainless steel. Therefore, on the inner surface of the mounting portion 46 where the main body 40 and the holding member 27 come into contact, dissimilar metals come into contact with each other.

[0056] In a contact area between dissimilar metals, when electronic conduction occurs in a corrosive environment, corrosion of one of the metals is accelerated, which increases the gap formed between the main body 40 and the holding member 27, and it is expected that refrigerant leakage will occur through the gap between the main body 40 and the holding member 27.

[0057] 1 and 2, the retaining member 27 is attached to the inside of the attachment portion 46, and is therefore located more inward than the inner step portion 47a in the electric expansion valve 1. That is, according to the electric expansion valve 1 according to the first embodiment, by forming the inner step portion 47a, it is possible to prevent moisture from penetrating between the retaining member 27 and the main body portion 40, and to prevent the contact portion between the retaining member 27 and the main body portion 40 from becoming a corrosive environment.

[0058] As a result, the electric expansion valve 1 of the first embodiment can suppress corrosion due to contact between dissimilar metals at the contact portion between the holding member 27 and the main body portion 40, and can suppress leakage of refrigerant between the holding member 27 and the main body portion 40.

[0059] As described above, the electric expansion valve 1 according to the first embodiment has a drive motor 10, a main body 40, a valve body 30, a retaining member 27, and a casing 54, and also has an inner step portion 47a as a step portion 47 adjacent to the inside of the cylindrical portion 54a of the casing 54.

[0060] As a result, the electric expansion valve 1 according to the first embodiment can lengthen the path for moisture to penetrate from the outside into the inside of the electric expansion valve 1 between the casing 54 and the main body 40 by forming the inner step portion 47a, and can increase the pressure loss in the moisture penetration path. In other words, by increasing the pressure loss in the moisture penetration path, the electric expansion valve 1 can prevent moisture from penetrating into the inside of the electric expansion valve 1 and can improve the waterproofness of the electric expansion valve 1.

[0061] Furthermore, by arranging the inner step portion 47a in the path of moisture penetration from the outside into the electric expansion valve 1, the moisture must move vertically when it penetrates. This allows the electric expansion valve 1 to increase the head of water required for moisture to penetrate from the outside into the electric expansion valve 1. Therefore, also from the perspective of the head of water required for moisture penetration from the outside, the electric expansion valve 1 can prevent moisture from penetrating into the electric expansion valve 1 and improve waterproofing.

[0062] In the electric expansion valve 1 according to the first embodiment, the main body 40 is made of a cast material using an aluminum alloy, and the holding member 27 is made of stainless steel. For this reason, if the contact area between the main body 40 and the holding member 27 becomes a corrosive environment due to the intrusion of moisture and becomes electrically conductive, it is expected that corrosion of the metal of either the main body 40 or the holding member 27 will be accelerated.

[0063] In this regard, in the electric expansion valve 1 according to the first embodiment, the formation of the inner step portion 47a suppresses the intrusion of moisture from the outside into the electric expansion valve 1, thereby suppressing a corrosive environment at the contact portion between the main body portion 40 and the holding member 27. As a result, the electric expansion valve 1 can prevent corrosion due to contact between dissimilar metals between the main body portion 40 and the holding member 27, and suppress refrigerant leakage between the main body portion 40 and the holding member 27.

[0064] (Second embodiment) Next, a second embodiment, which differs from the above-described embodiment, will be described with reference to Fig. 3. In the second embodiment, the type of valve device applied as the motor-operated valve differs from that in the first embodiment. In the second embodiment, a flow path unit 100 configured by integrating a plurality of electric expansion valves is used as the motor-operated valve.

[0065] 3, the flow path unit 100 according to the second embodiment is configured by assembling a plurality of valve units 70 (three in the second embodiment) to one main body 40. Three mounting portions 46, the same number as the valve units 70, are formed on the main body 40. As in the first embodiment, an inner step portion 47a is formed on the opening edge of each mounting portion 46.

[0066] Also, although not shown in the figure, the main body 40 has valve chambers 41 formed therein so as to communicate with each mounting portion 46, and each valve chamber 41 is connected to a component of the refrigeration cycle (e.g., a heat exchanger) via a refrigerant flow path 45.

[0067] Each valve unit 70 shown in FIG. 3 has the same configuration as the valve unit 70 according to the first embodiment, and is formed into a unit by assembling a drive motor 10, a reduction mechanism 20, a shaft case 26, a retaining member 27, a valve body 30, a casing 54, etc.

[0068] As in the first embodiment, the main body 40 in the second embodiment is formed from a cast material (e.g., AC4C) using an Al-Si-Mg aluminum alloy, and the retaining member 27 included in each valve unit 70 is made of stainless steel.

[0069] In the flow path unit 100 according to the second embodiment, an inner step portion 47a formed on the opening edge of each mounting portion 46 is disposed adjacent to the inside of the cylindrical portion 54a of the casing 54 that constitutes each valve unit 70.

[0070] Therefore, even in the flow path unit 100 to which multiple valve units 70 are attached, by forming each inner step portion 47a, it is possible to suppress the penetration of moisture through the gap between the casing 54 and the main body portion 40 of each valve unit 70, as in the first embodiment.

[0071] Also in the flow path unit 100, the holding member 27 of each valve unit 70 and each mounting portion 46 formed on the main body 40 are made of dissimilar metals and are in contact with each other. Therefore, if moisture penetrates into the contact area between the holding member 27 and the main body 40, creating a corrosive environment, it is expected that the gap between the holding member 27 and the main body 40 will widen due to dissimilar metal corrosion.

[0072] In this regard, in the flow path unit 100 of the second embodiment, an inner step portion 47a is formed on the opening edge of each mounting portion 46, thereby preventing moisture from entering between the casing 54 and the main body portion 40.

[0073] As described above, according to the flow path unit 100 of the second embodiment, even when multiple valve units 70 are assembled to one main body 40 as an electric valve according to the present disclosure, it is possible to obtain the same functional effects as those of the above-mentioned embodiment due to the configuration and operation.

[0074] Furthermore, according to the flow path unit 100 of the second embodiment, even when a configuration is adopted in which multiple valve units 70 are assembled to one main body portion 40, the formation of inner step portions 47a in each mounting portion 46 can suppress the occurrence of dissimilar metal corrosion.

[0075] (Third embodiment) Next, a third embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 4. In the third embodiment, an electric expansion valve 1 is used as the motor-operated valve. In the electric expansion valve 1 according to the third embodiment, the configuration of the cylindrical portion 54a of the casing 54 and the surroundings of the mounting portion 46 of the main body 40 differs from that of the first embodiment. Other configurations of the electric expansion valve 1 according to the third embodiment (e.g., the drive motor 10, the speed reduction mechanism 20, the valve main body 30, etc.) are the same as those of the above-described first embodiment, and therefore will not be described again.

[0076] 4, in the electric expansion valve 1 according to the third embodiment, a seal member 55 is disposed between the casing 54 and the main body 40. The seal member 55 is made of a water-impermeable material and prevents liquid from flowing in or out between the cylindrical portion 54a and the main body 40.

[0077] A so-called waterproof sheet made of ethylene propylene diene rubber (so-called EPDM) formed into a sheet shape is used as the sealing member 55 according to the third embodiment. As shown in Fig. 4, the sealing member 55 according to the third embodiment is sandwiched between the lower end of the cylindrical portion 54a of the casing 54 and the upper surface of the main body 40.

[0078] The end of the seal member 55 is disposed so as to contact the outer surface of the inner step portion 47a. In other words, the inner step portion 47a has the function of determining the position of the seal member 55 when the seal member 55 is disposed relative to the main body portion 40.

[0079] As described above, the sealing member 55 is formed in a sheet shape from ethylene propylene diene rubber, and is therefore elastically deformed when sandwiched between the cylindrical portion 54a and the upper surface of the main body 40. This allows the sealing member 55 to come into close contact with the surface of the cylindrical portion 54a of the casing 54, the upper surface of the main body 40, and the outer surface of the inner stepped portion 47a, thereby sealing the gap between the casing 54 and the main body 40.

[0080] The constituent material of the sealing member 55 is not limited to ethylene propylene diene rubber. Various constituent materials can be used for the sealing member 55 as long as the waterproofing of the sealing member 55 can be ensured. For example, the sealing member 55 may be made of an elastomer such as polyurethane, rubber, or silicone resin.

[0081] In the electric expansion valve 1 according to the third embodiment, the sealing member 55 is located outside the inner step portion 47a, and therefore the sealing member 55 can prevent moisture from entering between the inner step portion 47a and the cylindrical portion 54a. Therefore, according to the electric expansion valve 1 according to the third embodiment, waterproofness is improved by two components, the sealing member 55 and the inner step portion 47a, and therefore waterproofness of the inside of the electric expansion valve 1 can be reliably improved.

[0082] Furthermore, since the sealing member 55 is positioned using the inner step portion 47a, the electric expansion valve 1 of the third embodiment can elastically deform the sealing member 55 at an appropriate position, thereby reliably improving the waterproofing between the casing 54 and the main body portion 40.

[0083] As described above, according to the electric expansion valve 1 of the third embodiment, even if a sealing member 55 that seals between the main body 40 and the casing 54 is arranged outside the inner step portion 47a, the same functional effects as those of the above-mentioned embodiment can be obtained from the same configuration and operation.

[0084] 4, in the electric expansion valve 1 according to the third embodiment, the sealing member 55 is formed in a sheet shape and is sandwiched between the tip of the cylindrical portion 54a and the upper surface of the main body 40. Therefore, in the electric expansion valve 1 according to the third embodiment, the sealing member 55 seals the gap between the main body 40 and the casing 54, thereby improving waterproofing between the main body 40 and the casing 54. In other words, the electric expansion valve 1 according to the third embodiment can reliably prevent moisture from entering from the outside by providing the sealing member 55 in addition to the inner stepped portion 47a.

[0085] Furthermore, the sealing member 55 according to the third embodiment is disposed so that the end of the sealing member 55 contacts the outer surface of the inner step portion 47a. That is, the sealing member 55 can be disposed in an appropriate position by utilizing the inner step portion 47a, and therefore the sealing member 55 can reliably improve the waterproofness of the electric expansion valve 1.

[0086] (Fourth embodiment) Next, a fourth embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 5. The electric expansion valve 1 according to the fourth embodiment differs from the above-described third embodiment in the configuration and arrangement of the sealing member 55. The other configuration of the electric expansion valve 1 according to the fourth embodiment is the same as that of the above-described embodiments, so a repeated description will be omitted.

[0087] 5, in the electric expansion valve 1 according to the fourth embodiment, a seal member 55 is disposed on the outer surface of the cylindrical inner step portion 47a. The seal member 55 is formed in an annular shape from ethylene propylene diene rubber and constitutes a so-called O-ring. The seal member 55 according to the fourth embodiment seals the gap between the outer surface of the inner step portion 47a formed in the main body 40 and the inner surface of the cylindrical portion 54a in the casing 54, thereby improving the waterproofness between the main body 40 and the casing 54.

[0088] Therefore, according to the electric expansion valve 1 of the fourth embodiment, by disposing the annular seal member 55 on the inner stepped portion 47a, it is possible to reliably prevent moisture from entering from the outside.

[0089] As described above, according to the electric expansion valve 1 of the fourth embodiment, even if the configuration and arrangement of the sealing member 55 are changed, the same effects can be obtained as with the third embodiment described above due to the configuration and operation.

[0090] (Fifth embodiment) Next, a fifth embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 6. The electric expansion valve 1 according to the fifth embodiment differs from the above-described embodiments in the configuration around the inner step portion 47a. The other configuration of the electric expansion valve 1 according to the fifth embodiment is the same as that of the above-described embodiments, so a repeated description will be omitted.

[0091] In the electric expansion valve 1 according to the fifth embodiment, an outer step portion 47b is formed on the upper surface of the main body portion 40. The outer step portion 47b is formed by displacing the upper surface of the main body portion 40 vertically upward at a position spaced apart from the inner step portion 47a in the outward direction of the electric expansion valve 1.

[0092] Furthermore, in the electric expansion valve 1 according to the fifth embodiment, the distance between the inner step portion 47a and the outer step portion 47b corresponds to the thickness of the cylindrical portion 54a in the casing 54. That is, in the fifth embodiment, the inner step portion 47a and the outer step portion 47b form a groove portion 48 into which the cylindrical portion 54a is fitted.

[0093] As a result, in the electric expansion valve 1 according to the fifth embodiment, it is possible to lengthen the moisture infiltration path formed between the groove 48 formed by the inner step portion 47a and the outer step portion 47b and the cylindrical portion 54a fitted into the groove portion 48, thereby improving pressure loss in the infiltration path. That is, the electric expansion valve 1 according to the fifth embodiment improves pressure loss in the moisture infiltration path formed between the main body 40 and the casing 54 by forming the inner step portion 47a and the outer step portion 47b, and can prevent moisture from infiltrating into the electric expansion valve 1.

[0094] Furthermore, in the electric expansion valve 1 according to the fifth embodiment, the vertical movement of water along the outer step portion 47b is added to the vertical movement of water along the inner step portion 47a, so the head of water required for water to penetrate to the interior can be increased. According to the electric expansion valve 1 according to the fifth embodiment, by providing the inner step portion 47a and the outer step portion 47b, the head of water required for water to penetrate into the electric expansion valve 1 can be increased, and water penetration into the electric expansion valve 1 can be suppressed.

[0095] As described above, according to the electric expansion valve 1 of the fifth embodiment, even if the groove portion 48 is formed by forming the outer step portion 47b in addition to the inner step portion 47a, the same functional effects as those of the above-mentioned embodiments can be obtained from the configuration and operation.

[0096] (Sixth embodiment) Next, a sixth embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 7. In the sixth embodiment, the configuration around the groove portion 48 formed by the inner step portion 47a and the outer step portion 47b differs from that of the fifth embodiment. The other configurations of the electric expansion valve 1 according to the sixth embodiment are the same as those of the above-described embodiments, and therefore a repeated description of the other configurations will be omitted.

[0097] 7, the main body 40 of the electric expansion valve 1 according to the sixth embodiment has a groove 48 consisting of an inner step 47a and an outer step 47b. The configuration of the groove 48 is the same as that of the fifth embodiment described above.

[0098] In the sixth embodiment, a sealing member 55 is disposed on the bottom surface of the groove portion 48 (i.e., the upper surface of the main body portion 40). The sealing member 55 is a waterproof sheet made of ethylene propylene diene rubber, as in the above-described embodiments.

[0099] The cylindrical portion 54a of the casing 54 is fitted inside the groove 48 (i.e., between the inner step portion 47a and the outer step portion 47b). The sealing member 55 is disposed at the bottom of the groove 48, and is therefore sandwiched between the upper surface of the main body 40 and the lower end of the cylindrical portion 54a. As a result, the sealing member 55 is elastically deformed by the pressure from the tip of the cylindrical portion 54a, and is brought into close contact with the inner wall surface of the bottom of the groove 48 and the surface of the lower end of the cylindrical portion 54a.

[0100] As a result, the electric expansion valve 1 according to the sixth embodiment can seal the water infiltration path formed between the main body 40 and the casing 54 between the inner step portion 47a and the outer step portion 47b. Therefore, by using the sealing member 55 in addition to the inner step portion 47a and the outer step portion 47b, the electric expansion valve 1 according to the sixth embodiment can suppress water infiltration into the interior and improve waterproofing.

[0101] In the electric expansion valve 1 according to the sixth embodiment, a waterproof sheet is used as the sealing member 55, but the configuration is not limited as long as it can seal the gap between the casing 54 and the main body 40 within the groove 48. For example, an O-ring as in the fourth embodiment may be used as the sealing member 55.

[0102] 7, as long as the gap between the main body 40 and the casing 54 can be sealed inside the groove 48. For example, the seal member 55 may be disposed on the surface of either the inner step 47a or the outer step 47b, as long as it is located inside the groove 48.

[0103] As described above, according to the electric expansion valve 1 of the sixth embodiment, even when a sealing member 55 is placed inside the groove portion 48 consisting of the inner step portion 47a and the outer step portion 47b, the same functional effects as those of the above-mentioned embodiments can be obtained from the same configuration and operation.

[0104] (Seventh embodiment) Next, a seventh embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 8. The electric expansion valve 1 according to the seventh embodiment differs from the above-described embodiments in the configuration of the cylindrical portion 54a of the casing 54. The other configurations of the electric expansion valve 1 according to the seventh embodiment (e.g., the drive motor 10, the valve body 30, etc.) are the same as those of the above-described embodiments, and therefore will not be described again.

[0105] 8, the electric expansion valve 1 according to the seventh embodiment has a fitting recess 54b at the tip of a cylindrical portion 54a in a casing 54. The fitting recess 54b is formed by recessing the tip surface of the cylindrical portion 54a in a groove shape so that an inner stepped portion 47a formed in the main body 40 can be fitted into the fitting recess 54b.

[0106] In the electric expansion valve 1 of the seventh embodiment, when the valve unit 70 is assembled to the mounting portion 46 of the main body 40, the cylindrical inner step portion 47a formed on the opening edge of the mounting portion 46 is fitted into the fitting recess 54b in the casing 54.

[0107] As a result, in the electric expansion valve 1 according to the seventh embodiment, it is possible to lengthen the moisture infiltration path formed between the fitting recess 54b formed on the tip surface of the cylindrical portion 54a and the inner step portion 47a that fits into the fitting recess 54b, thereby improving pressure loss in the infiltration path. That is, the electric expansion valve 1 according to the seventh embodiment improves pressure loss in the moisture infiltration path formed between the main body 40 and the casing 54 by forming the inner step portion 47a and the fitting recess 54b, and can prevent moisture from infiltrating into the electric expansion valve 1.

[0108] As described above, according to the electric expansion valve 1 of the seventh embodiment, even if a fitting recess 54b is formed at the tip of the cylindrical portion 54a in addition to the inner step portion 47a, it is possible to obtain the same functional effects as those of the above-mentioned embodiments from the configuration and operation.

[0109] (Eighth embodiment) Next, an eighth embodiment, which differs from the above-described embodiments, will be described with reference to Fig. 9. In the eighth embodiment, the configuration around the fitting recess 54b formed in the cylindrical portion 54a of the casing 54 differs from that of the seventh embodiment. Therefore, the other configurations of the electric expansion valve 1 according to the eighth embodiment are the same as those of the above-described embodiments, and therefore a repeated description of the other configurations will be omitted.

[0110] 9, the casing 54 of the electric expansion valve 1 according to the eighth embodiment has a fitting recess 54b on the tip surface of the cylindrical portion 54a. The configuration of the fitting recess 54b is the same as that of the seventh embodiment described above.

[0111] In the eighth embodiment, a seal member 55 is disposed on the bottom surface of the groove portion 48 (i.e., the upper surface of the main body portion 40). As in the above-described embodiments, the seal member 55 is a so-called O-ring formed in an annular shape from ethylene propylene diene rubber.

[0112] A cylindrical inner step portion 47a formed on the main body portion 40 is fitted into the fitting recess 54b of the cylindrical portion 54a. In the eighth embodiment, the seal member 55 is disposed at the back of the fitting recess 54b, and therefore the seal member 55 is sandwiched between the inner surface of the fitting recess 54b and the upper end of the inner step portion 47a formed on the main body portion 40. As a result, the seal member 55 is elastically deformed by the pressure from the upper end of the inner step portion 47a, and is in close contact with the inner surface of the fitting recess 54b and the upper end face of the inner step portion 47a.

[0113] As a result, the electric expansion valve 1 according to the eighth embodiment can seal the water infiltration path formed between the main body 40 and the casing 54 between the inner step portion 47a and the fitting recess 54b. Therefore, by using the sealing member 55 in addition to the inner step portion 47a and the fitting recess 54b, the electric expansion valve 1 according to the eighth embodiment can suppress water infiltration into the interior and improve waterproofing.

[0114] In the electric expansion valve 1 according to the eighth embodiment, an O-ring is used as the sealing member 55, but the configuration is not limited as long as it can seal the gap between the casing 54 and the main body 40 inside the fitting recess 54b. For example, a waterproof sheet as in the above-described embodiment may be used as the sealing member 55.

[0115] Furthermore, the position where the seal member 55 is disposed is not limited to the position shown in FIG. 9, as long as it can seal the gap between the main body 40 and the casing 54 inside the fitting recess 54b.

[0116] As described above, according to the electric expansion valve 1 of the eighth embodiment, even when the sealing member 55 is arranged inside the fitting recess 54b in the cylindrical portion 54a of the casing 54, the same functional effects as those of the above-mentioned embodiments can be obtained from the same configuration and operation.

[0117] (Other embodiments) The present disclosure is not limited to the above-described embodiments, and various modifications can be made as follows within the scope of the present disclosure.

[0118] (a) The configuration shown in Fig. 10 can also be employed as a motor-operated valve according to the present disclosure. The example shown in Fig. 10 is an application example to an electric expansion valve 1 configured similarly to the first embodiment described above. The difference between the example shown in Fig. 10 and the first embodiment described above is that, instead of the inner stepped portion 47a, an outer stepped portion 47b is provided that is formed adjacent to the outer surface of the cylindrical portion 54a of the casing 54.

[0119] 10, the path of moisture penetration from the outside to the inside between the casing 54 and the main body 40 is lengthened by the configuration that extends vertically between the cylindrical portion 54a and the outer stepped portion 47b. As a result, the electric expansion valve 1 according to the example shown in FIG. 10 can also improve the pressure loss of the path of moisture penetration from the outside to the inside, and can improve waterproofing of the interior.

[0120] 10, a seal member can also be disposed between the cylindrical portion 54a of the casing 54 and the outer step portion 47b formed on the main body 40. In this case, the seal member can be of various shapes (for example, the above-mentioned watertight sheet, O-ring, etc.) and materials, as long as it can seal the gap between the cylindrical portion 54a and the outer step portion 47b. Furthermore, the seal member can be disposed on either the cylindrical portion 54a side or the outer step portion 47b side.

[0121] (b) In the above-described embodiment, the motor-operated valve according to the present disclosure is applied to the electric expansion valve 1 and the flow path unit 100 integrating multiple electric expansion valves 1, but the present disclosure is not limited to this. The motor-operated valve according to the present disclosure can be applied to various valve devices, such as an electric on-off valve or an electric multi-way valve.

[0122] (c) In the above-described embodiment, the motor-operated valve is applied to the refrigeration cycle of an air conditioner, but the present disclosure is not limited to this. The motor-operated valve according to the present disclosure can be applied to any fluid circuit. For example, the motor-operated valve may be applied to a refrigeration cycle for a residential facility, or to a heat medium circuit (coolant circuit) that constitutes a vehicle air conditioner. [Explanation of symbols]

[0123] 1 Electric expansion valve 10 Drive motor 27 Retaining member 33 Valve body 40 Main body 45 refrigerant flow path 46 Mounting part 47 Step 47a Inner step 54 Casing

Claims

1. a main body (40) having a flow path (45) therein through which a fluid flows; a driving unit (10) that uses electricity to generate a driving force for moving a valve body (33) that adjusts the flow rate of the fluid flowing through the flow path; a holding member (27) attached to an attachment portion (46) formed on one surface of the main body portion, guiding the movement direction of the valve body toward the inside of the flow path and positioning the valve body and the drive portion; a casing (54) attached to the main body portion on one side thereof so as to cover the retaining member and the drive portion, An electric valve in which a step portion (47) is formed around the mounting portion of the main body portion at a position adjacent to and inside the contact portion with the casing, by displacing one surface of the main body portion vertically.

2. The motor-operated valve according to claim 1, wherein a sealing member (55) that seals a gap formed between the main body portion and the casing is arranged around the mounting portion.

3. The motor-operated valve according to claim 2, wherein the seal member is disposed around the mounting portion so as to contact the outside of the stepped portion.

4. the main body is made of a casting material containing a first metal, 4. The motor-operated valve according to claim 1, wherein the retaining member is made of a second metal different from the first metal.

5. a valve unit (70) including the drive unit, the casing, and the valve body; The main body portion is formed with a plurality of the attachment portions and the step portions, The motor-operated valve according to claim 4, wherein the valve unit is configured to be attached to the mounting portion and the stepped portion, respectively.

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