Motor-operated valve

Abstract

To confirm brazing material permeation between a valve body and a valve seat member from an opposite side of a brazing material input side.SOLUTION: A motor-operated valve 11 includes: a valve body 13 having an opening on a bottom surface; a valve seat member 21 having a communication hole 22 communicating with a valve chamber 14, having a valve seat 23, and brazed to the valve body being inserted into the opening; a valve body 17 which advances / retreats with respect to the valve seat; an electric motor 41 for driving the valve body; and a transmission mechanism 31 for converting rotational drive force of the electric motor into a linear motion and transmitting the linear motion to the valve body. The valve seat member includes: a positioning part 24 for restricting a relative movement of the valve body between the valve body and the valve seat member in a direction orthogonal to an axis line, at a portion being inserted into the valve body; and a clearance part 25 for forming a gap where a brazing material can permeate between itself and a valve body inner peripheral surface. The valve seat member is communicated with both of any of the valve chamber and a bottom surface side outside part of the valve body and the gap, and has formed a brazing material circulation groove where the brazing material can circulate on an outer peripheral surface of the positioning part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrically operated valve, and more particularly to the structure of a valve seat member that is brazed to a valve body. [Background technology]

[0002] 2. Description of the Related Art Motor-operated valves, which use an electric motor such as a stepping motor to control the opening degree of a valve, have conventionally been used in refrigeration cycle devices having a refrigerant circuit, such as air conditioners, refrigeration devices, and freezing devices.

[0003] In such motor-operated valves, the valve body is made of a cylindrical member with openings on the top and bottom, a support member for supporting the valve disc and an electric motor for driving the valve disc are installed on the top side of the valve body, and the opening on the bottom side of the valve body is sometimes closed with a valve seat member equipped with a refrigerant flow path port and a valve seat. The valve seat member is provided so that its upper part is inserted into the opening on the bottom side of the valve body, and the inserted part is joined to the valve body by brazing.

[0004] Furthermore, the following patent documents disclose such motor-operated valves. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-130271 A [Patent Document 2] International Publication No. 2020 / 230382 Summary of the Invention [Problem to be solved by the invention]

[0006] In an electrically operated valve having the above-described structure, it is desirable for the valve seat member to fit into the valve body without any gaps from the viewpoint of increasing the coaxiality (the accuracy of alignment between the central axis of the valve body and the central axis of the valve seat) between the valve body and the valve seat, which are arranged opposite each other via the valve body. However, in order to braze the valve seat member to the valve body, a gap of an appropriate size (for example, about 0.05 mm) is required between the valve seat member and the valve body.

[0007] This is because the molten brazing material must penetrate between the base materials (the valve body and the valve seat member), and if the gap is too narrow, the brazing (penetration of the brazing material) may deteriorate, resulting in poor bonding. Also, if the brazing is insufficient, the support strength of the valve seat decreases, impairing the durability of the motor-operated valve and making it impossible to obtain sufficient airtightness in the valve chamber, so it is desirable to provide a means for checking the brazing.

[0008] SUMMARY OF THE PRESENTLY PREFERRED EMBODIMENT An object of the present invention is therefore to make it possible to check the soldering between the valve body and the valve seat member. [Means for solving the problem]

[0009] In order to solve the above problems and achieve the object, the motor-operated valve according to the present invention comprises a valve body having a valve chamber therein and an opening on a bottom surface, a valve seat member having a communication hole communicating with the valve chamber and having a valve seat at an end of the communication hole on the valve chamber side, at least a portion of which is inserted into the valve body and brazed to the valve body so as to close the opening, a first flow path pipe communicating with the valve chamber, a second flow path pipe communicating with the valve chamber via the communication hole, a valve element that moves toward and away from the valve seat to control the amount of fluid passing through, an electric motor that drives the valve element, and a valve seat member that rotates the electric motor. The valve seat member has, at the portion inserted into the valve body, a positioning portion which restricts relative movement between the valve body and the valve seat member in a direction perpendicular to the axis of the valve body, and a clearance portion which forms a gap between the inner surface of the valve body and the positioning portion and through which molten brazing material can penetrate, and a brazing material flow groove is formed on the outer surface of the positioning portion which communicates with both the gap and either the valve chamber or the outside of the bottom side of the valve body, and through which the molten brazing material can flow.

[0010] In the motor-operated valve according to the present invention, the valve seat member is fixed to the valve body by brazing, and the valve seat member is provided with a positioning portion that enables the valve seat member to be positioned relative to the valve body so as to increase the concentricity with the valve body (the accuracy of alignment between the central axis of the valve body and the central axis of the valve seat member), and a clearance portion that forms an appropriate gap between the valve body and the valve seat member so that the molten brazing material reliably penetrates between the valve body and the valve seat member during brazing. That is, in the present invention, the positioning portion and the clearance portion are formed as separate parts (portions) on the valve seat member, thereby achieving both positioning accuracy and good solderability.

[0011] The positioning portion and the clearance portion are arranged adjacent to each other in the axial direction of the valve body and the valve seat member. That is, either (1) the positioning portion is arranged on the valve chamber side in the axial direction of the valve body, and the clearance portion is arranged on the bottom surface side of the valve body in the axial direction of the valve body (this mode is referred to as the "first mode"), or conversely, (2) the positioning portion is arranged on the bottom surface side of the valve body in the axial direction of the valve body, and the clearance portion is arranged on the valve chamber side in the axial direction of the valve body (this mode is referred to as the "second mode").

[0012] A brazing material flow groove is formed on the outer peripheral surface of the positioning portion, through which molten brazing material can flow. One end of this brazing material flow groove communicates with the gap formed by the clearance portion (hereinafter, this gap will be referred to as the "joint gap"). The other end of the brazing material flow groove communicates with the valve chamber in the first embodiment, and communicates with the outside of the bottom side of the valve body in the second embodiment. In this way, in the motor-operated valve of the present invention, the joint gap and the brazing material flow groove communicate with each other to form a brazing material flow passage extending between the outside of the bottom side of the valve body and the valve chamber.

[0013] During brazing, in order to allow the brazing material to penetrate into the joint gap, the valve body with the valve seat member installed is positioned by the positioning portion and oriented so that the clearance portion is on the upper side and the positioning portion is on the lower side, the brazing material is placed on the end of the joint gap (the end opposite to the side communicating with the brazing material flow groove), and the valve body and the valve seat member are then placed in, for example, a furnace and heated.

[0014] The molten brazing material then flows into and down the joint gap, and then further into the brazing material flow groove that communicates with the joint gap, and flows out through the brazing material flow groove to the opposite side, that is, the opposite side of the positioning portion from the side adjacent to the clearance portion.

[0015] For each of the above aspects, in the first aspect, since the clearance portion is disposed on the bottom side of the valve body, the valve body is turned upside down (with the bottom side facing up), and the brazing material is placed on the end of the clearance portion (the end of the joining gap on the bottom side of the valve body) and melted. The molten brazing material then permeates the joining gap, passes through the brazing material flow groove, and flows out into the valve chamber. This flow (the brazing material that has flowed out and solidified) can be confirmed from the valve chamber side.

[0016] On the other hand, in the second embodiment, since the clearance portion is disposed on the valve chamber side, the valve body is stood upright with the bottom surface facing downwards, and the brazing material is placed on the end portion of the clearance portion (the end portion of the joining gap on the valve chamber side) and melted. The molten brazing material then permeates the joining gap, passes through the brazing material flow groove, and flows out from the bottom side of the valve body to the outside. This flow (the brazing material that has flowed out and solidified) can be confirmed from the bottom side of the valve body.

[0017] Thus, according to the present invention, by visually checking the flow of the brazing material from the opposite side to the brazing material input side (the side where the brazing material is placed during brazing) across the valve seat member, it is possible to confirm that the brazing material has reliably penetrated into the joint gap and that a good brazing flow (joining of the valve seat member and the valve body) has been obtained. Also, in the present invention, a through passage is formed between the valve chamber and the outside of the bottom side of the valve body by the joint gap and the brazing material flow groove, so that gas that may be generated from the brazing material during brazing can be discharged from the joint, preventing the formation of voids (cavities) in the joint.

[0018] Furthermore, according to the present invention, it is possible to simultaneously achieve a highly coaxial arrangement of the valve seat member relative to the valve body (and therefore the valve seat relative to the valve disc) and a good joint of the valve seat member relative to the valve body (high mechanical strength of the joint and high airtightness can be ensured) by dividing the positioning portion and the clearance portion into separate portions in the present invention.

[0019] In other words, according to the present invention, since there is no need to consider the brazing (the formation of a gap suitable for the penetration of the brazing material) when forming the positioning portion, it is possible to precisely align the central axes of the valve seat member and the valve body by, for example, press-fitting the valve seat member into the valve body (fitting the positioning portion into the valve body without a gap). Conversely, since there is no need to consider the positioning of the valve seat member relative to the valve body when forming the clearance portion, it is possible to set a gap of an optimal size for the brazing, and ensure the brazing.

[0020] The axial positioning of the valve seat member relative to the valve body can be achieved, for example, by providing the valve body with a positioning step (step) that restricts the movement of the valve seat member in the axial direction of the valve body. The valve seat member is positioned in the axial direction by forming a step on the inner peripheral surface of the valve body and abutting the valve seat member against the step. As another example, a gradually tapered inner peripheral surface may be provided on the inner peripheral surface of the valve body where the valve seat member is inserted, and a wedge-like inclined outer peripheral surface may be formed on the positioning portion. With this structure in which the valve seat member is inserted like a wedge into the inclined inner peripheral surface formed on the valve body and the inclined surfaces are abutted against each other, it is possible to simultaneously perform positioning in the direction perpendicular to the axis of the valve body and positioning in the axial direction of the valve body.

[0021] The brazing material flow groove can be, for example, a spiral groove extending in a spiral shape on the outer peripheral surface of the positioning portion. It is also possible to configure the brazing material flow groove by a linear groove extending parallel to the axis of the valve body. When the brazing material flow groove is configured by a linear groove, the groove may be one, but it is preferable to configure it by a plurality of grooves arranged at intervals in the circumferential direction of the valve seat member, since the brazing material flow around the entire circumference of the valve seat member (joint gap) can be more reliably confirmed. In addition, the linear groove makes it easy to process the groove, and the brazing material filling the joint gap can be reliably guided to the opposite side to the brazing material input side to confirm the brazing material flow.

[0022] In the present invention, the first and second flow passage pipes are used either as an inlet pipe for introducing the refrigerant into the valve chamber, or as an outlet pipe for discharging the refrigerant from the valve chamber. That is, when the first flow passage pipe is used as the inlet pipe, the second flow passage pipe becomes the outlet pipe, and conversely, when the second flow passage pipe is used as the inlet pipe, the first flow passage pipe becomes the outlet pipe. Effect of the Invention

[0023] According to the present invention, the brazing process between the valve body and the valve seat member can be visually observed from the side opposite to the side where the brazing material is added, making it possible to confirm that the valve seat member is securely joined to the valve body.

[0024] Other objects, features and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a vertical sectional view showing a motor-operated valve according to a first embodiment of the present invention in a closed state. [Diagram 2] FIG. 2 is an enlarged vertical cross-sectional view showing a joint portion (portion B1 in FIG. 1) between a valve body and a valve seat member of the motor-operated valve according to the first embodiment. [Diagram 3] FIG. 3 is a front view showing a valve seat member of the motor-operated valve according to the first embodiment. [Figure 4] FIG. 4 is an enlarged view showing the brazing material flow groove (portion B2 in FIG. 3) of the valve seat member of the motor-operated valve according to the first embodiment. [Diagram 5] FIG. 5 is a vertical sectional view showing the motor-operated valve according to the first embodiment in an open state. [Figure 6] FIG. 6 is an enlarged longitudinal sectional view, similar to FIG. 2, showing a joint portion between a valve body and a valve seat member of a motor-operated valve according to a second embodiment of the present invention. [Figure 7] FIG. 7 is an enlarged longitudinal sectional view, similar to FIG. 2, showing a joint portion between a valve body and a valve seat member of a motor-operated valve according to a third embodiment of the present invention. [Figure 8] FIG. 8 is an enlarged longitudinal sectional view, similar to FIG. 2, showing a joint portion between a valve body and a valve seat member of a motor-operated valve according to a fourth embodiment of the present invention. [Figure 9] FIG. 9 is an enlarged longitudinal sectional view, similar to FIG. 2, showing a joint portion between a valve body and a valve seat member of a motor-operated valve according to a fifth embodiment of the present invention. [Figure 10] FIG. 10 is an enlarged longitudinal sectional view, similar to FIG. 2, showing a joint portion between a valve body and a valve seat member of a motor-operated valve according to a sixth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] [First embodiment] As shown in Figures 1 to 5, an electric valve 11 according to a first embodiment of the present invention is an electric valve suitable for use in adjusting a refrigerant flow rate in a refrigeration cycle device such as a heat pump type heating and cooling system, and has a valve section 12 that controls the flow of refrigerant, an electric motor (drive unit) 41 that drives the valve section 12, a reduction mechanism 51 that reduces the rotation of the electric motor 41, and a transmission mechanism (screw feed mechanism) 31 that converts the rotation reduced by the reduction mechanism 51 into linear motion and transmits it to the valve section 12 (valve body 17).

[0027] In each drawing, mutually orthogonal two-dimensional coordinates representing the up-down and left-right directions are appropriately displayed, and the following explanation is based on these directions, but the motor-operated valve of the present invention and each embodiment of this application can be used in various orientations, and each direction is for the convenience of explanation, and the configuration of each part of the present invention is not limited by these directions. In addition, the axial direction of the valve body 13, the valve seat member 21, etc. coincides with the up-down direction and is perpendicular to the radial direction. Furthermore, although the terms "vertical" and "horizontal" are sometimes used, the vertical direction coincides with the axial direction and the up-down direction, and the direction perpendicular to the vertical direction is the horizontal direction including the left-right direction.

[0028] The valve portion 12 comprises a valve body 13 having a valve chamber 14 therein and formed of a cylindrical member with its top and bottom open (having a top opening and a bottom opening); a first flow path pipe 15 joined to the valve body 13 so as to penetrate the side wall of the valve body 13 and communicate with the valve chamber 14; a valve seat member 21 having a valve seat 23 on its upper surface and joined to the bottom portion of the valve body 13 so as to close the bottom opening of the valve body 13; a valve body 17 supported by a valve body support member 19 and disposed in the valve chamber 14 so as to be movable forward and backward (up and down) relative to the valve seat 23; a second flow path pipe 16 fixed to the valve seat member 21 so as to communicate with the valve chamber 14; and a connecting member 18 joined to the top portion of the valve body 13 so as to close the top opening of the valve body 13 so as to allow a drive unit 41 to be installed in the valve portion 12.

[0029] The valve body 13 has, at its lower end, a first enlarged diameter portion 13a having an inner diameter larger than that of the upper and middle portions (portions forming the valve chamber 14) of the valve body 13, and a second enlarged diameter portion 13b having an inner diameter even larger than that of the first enlarged diameter portion 13a. The first enlarged diameter portion 13a and the second enlarged diameter portion 13b are adjacent to each other in the axial direction (vertical direction), and the first enlarged diameter portion 13a is located above (closer to the valve chamber 14) than the second enlarged diameter portion 13b located at the lowest end of the valve body 13. In addition, by forming the first enlarged diameter portion 13a, a step 13c (see FIG. 2) is formed between (at the boundary portion) the middle portion of the valve body 13 and the first enlarged diameter portion 13a, and the valve seat member 21 is positioned in the axial direction relative to the valve body 13 by abutting against this step 13c.

[0030] The valve seat member 21 is a ring-shaped member having a through hole 22 extending in the up-down direction in the center, and a valve seat 23 is provided on the upper edge of the through hole 22. A step is formed in the middle of the through hole 22, and the second flow path pipe 16 is fixed to the valve seat member 21 by inserting the second flow path pipe 16 into the through hole 22 from the underside and welding it against the step.

[0031] A positioning portion 24 that is press-fitted into the first enlarged diameter portion 13a at the lower end of the valve body 13, and a clearance portion 25 that is disposed opposite (diametrically facing) the second enlarged diameter portion 13b are formed on the outer circumferential surface of the valve seat member 21. The positioning portion 24 and the clearance portion 25 are adjacent to each other in the vertical direction, and in this embodiment, the positioning portion 24 is disposed on the upper side (the side closer to the valve chamber 14) and the clearance portion 25 is disposed on the lower side (the side closer to the bottom surface of the valve body 13).

[0032] The positioning portion 24 is fitted (for example, by an intermediate fit or a tight fit) into the first enlarged portion 13a of the valve body 13 so that no gap is formed between it and the first enlarged portion 13a of the valve body 13, thereby restricting the relative movement deviation between the valve body 13 and the valve seat member 21 in the horizontal direction (radial direction of the valve body 13 and the valve seat member 21) and functioning to position the valve seat member 21 (i.e., the valve seat 23) coaxially with the valve body 13 (i.e., the valve body 17) (aligning the central axis a1 of the valve seat member 21 and the valve seat 23 with the central axis A1 of the valve body 13 and the valve body 17).

[0033] On the other hand, when the positioning portion 24 is fitted into the first enlarged diameter portion 13a, the clearance portion 25 forms a constant gap (joint gap) 27 between it and the second enlarged diameter portion 13b of the valve body 13, and serves the function of allowing the molten brazing material to penetrate during brazing.

[0034] Furthermore, the positioning portion 24 is provided with a brazing material flow groove 26. This brazing material flow groove 26 extends spirally on the outer circumferential surface of the positioning portion 24, and is formed so that one end communicates with the joint gap 27 formed by the clearance portion 25 and the other end communicates with the valve chamber 14. Therefore, in this embodiment, the joint gap 27 and the brazing material flow groove 26 communicating therewith form a through passage that extends from the outside of the bottom side of the valve body 13 to the valve chamber 14.

[0035] Therefore, as shown in FIG. 2, with the valve body 13 turned upside down (with the bottom surface facing up and the valve chamber 14 facing down), if a brazing filler metal 28 is placed on the end of the clearance portion 25 (the end of the joining gap 27 on the bottom surface side of the valve body) and melted (for example, the valve body 13 and the valve seat member 21 with the brazing filler metal 28 placed thereon are placed in a furnace and heated), the melted brazing filler metal that has permeated the joining gap 27 will pass through the brazing filler metal flow groove 26 and reach the valve chamber 14, and by visually checking the brazing filler metal (see symbol 28a in FIG. 2) from the valve chamber 14 side, it can be confirmed that the brazing filler metal 28 has reliably permeated and the valve seat member 21 has been joined to the valve body 13.

[0036] The other configurations of the valve section 12 and the specific configurations of the electric motor (drive unit) 41, reduction mechanism 51, and transmission mechanism 31 may vary and are not limited to a specific structure, but will be described below as an example.

[0037] In this embodiment, a stepping motor is used as the electric motor 41 that drives the valve body 17. This stepping motor 41 is composed of a stator 42 installed on the outside (outer periphery) of a cylindrical can (sealed container) 39 with no bottom and a lid (the bottom is open and the top is closed) that is fixed to the connecting member 18 so as to cover the upper surface of the connecting member 18, and a rotor 43 installed inside (inner periphery) of the can 39 so as to be rotatable.

[0038] The stator 42 includes a yoke 44, a coil 46 formed by winding a wire around a bobbin 45, and a resin molded cover 47 that covers the yoke 44 and the coil 46. On the other hand, the rotor 43 is configured by integrally connecting a cylindrical rotor member 48 made of a magnetic material and a sun gear member 52 made of a resin material. A shaft 50 is inserted into the center of the sun gear member 52, and the upper part of the shaft 50 is supported by a support member 49 arranged inside the top of the can 39.

[0039] The sun gear 53 of the sun gear member 52 meshes with a plurality of planetary gears 54 rotatably supported on a shaft 55 provided on a carrier 56 placed on the bottom surface of the output gear 59. The upper part of the planetary gear 54 meshes with an annular ring gear (internal tooth fixed gear) 58 attached to the upper part of a cylindrical member 40 fixed to the upper part of the valve body support member 19, and the lower part of the planetary gear 54 meshes with an internal tooth gear 57 of an annular output gear 59. The number of teeth of the ring gear 58 and the number of teeth of the internal tooth gear 57 of the output gear 59 are slightly different, so that the rotation speed of the sun gear 53 is reduced at a large reduction ratio and transmitted to the output gear 59. Incidentally, these gear mechanisms (sun gear 53, planetary gear 54, ring gear 58 and output gear 59) constitute a reduction mechanism (paradise planetary gear reduction mechanism) 51 that reduces the rotation speed of the electric motor 41 described above.

[0040] The connecting member 18 joined to the upper surface of the valve body 13 is a ring-shaped member with a through hole in the center, into which a valve body support member 19 that supports the valve body 17 is fitted. The valve body support member 19 has a valve body support member main body 19a in the shape of a cylindrical container with a bottom and no lid, and a cylindrical cylinder portion 19c that hangs down vertically downward from the underside of a bottom plate portion 19b of the valve body support member main body 19a. The valve body support member main body 19a supports the valve body upper portion 17b that penetrates the bottom plate portion 19b so that it can slide in the vertical direction. The cylinder portion 19c supports the valve body lower portion 17a (the upper portion of the valve body lower portion 17a) so that it can slide in the vertical direction.

[0041] A cylindrical bearing member 32 is fitted into the upper part of the valve body support member 19, and the upper surface of the valve body support member 19 is crimped to fix the bearing member 32. An output gear 59 is in slidable contact with the upper surface of the bearing member 32. The upper part of a stepped cylindrical output shaft 61 is press-fitted into the center of the bottom of the output gear 59, and the lower part of the output shaft 61 is rotatably inserted into a fitting hole 32b formed in the center of the upper surface of the bearing member 32. The lower end of the shaft 50 is rotatably fitted into the upper part of the output shaft 61.

[0042] A female threaded portion 32a is formed at the lower center portion of the bearing member 32, and a male threaded portion 33a formed on the outer circumferential surface of the screw drive member 33 is screwed into this female threaded portion 32a. The screw feed mechanism 31 consisting of the bearing member 32 (female threaded portion 32a) and the screw drive member 33 (male threaded portion 33a) constitutes a transmission mechanism that converts the rotational motion supplied from the stepping motor 41 via the reduction gear mechanism 51 into linear motion in the vertical direction and transmits it to the valve body 17.

[0043] Here, the output gear 59 rotates at a constant position in the vertical direction without moving up and down, and a flat plate-like portion 33b provided at the upper end of the screw drive member 33 is inserted into a slit-like fitting groove 61a provided at the lower end of the output shaft 61 connected to the output gear 59 to transmit the rotational motion of the output gear 59 to the screw drive member 33. The plate-like portion 33b provided on the screw drive member 33 slides up and down within the fitting groove 61a of the output shaft 61, so that when the output gear 59 (rotor 43) rotates, the screw drive member 33 moves linearly up and down by the screw feed mechanism 31, even though the output gear 59 and the output shaft 61 do not move up and down.

[0044] The linear motion of the screw drive member 33 is transmitted to the valve element 17 via a ball joint 34 consisting of a ball 35 and a ball seat 36 fitted into a fitting hole 17d provided in the center of the top surface of the valve element upper part 17b. The valve element 17 consists of a valve element upper part 17b that penetrates the bottom plate part 19b of the valve element support member main body 19a, and a valve element lower part 17a that is arranged in the cylinder part 19c and the valve chamber 14. The valve element upper part 17b penetrates the bottom plate part 19b of the valve element support member main body 19a and also penetrates the bottom plate part 37a of the spring receiving member 37 arranged on the inner bottom surface of the valve element support member main body 19a, and has a head part 17c at its upper end that is expanded in diameter like a flange.

[0045] The spring receiving member 37 has a bottom plate portion 37a that allows the valve body upper portion 17b to penetrate and abuts against the lower peripheral edge portion of the head portion 17c from below, a cylindrical peripheral wall portion 37c that forms a ring-shaped gap between the inner peripheral surface of the valve body support member main body 19a, and a flange portion 37b that horizontally extends outward from the upper end of the peripheral wall portion 37c. A compression coil spring 38 is provided between the flange portion 37b of the spring receiving member 37 and the bottom plate portion 19b of the valve body support member main body 19a. This compression coil spring 38 constantly urges the valve body 17 (the head portion 17c of the valve body upper portion 17b) upward via the bottom plate portion 37a of the spring receiving member 37. As a result, even when the screw driving member 33 moves upward, the screw driving member 33 and the valve body 17 that are in contact with each other via the ball joint 34 do not separate, and the screw driving member 33 and the valve body 17 are integrated in the vertical direction.

[0046] The screw drive member 33 on the drive section side rotates and slides around the central axis A1 relative to the valve disc 17 via the ball 35, and the rotation of the screw drive member 33 is not transmitted to the valve disc 17. In the motor-operated valve 11 of this embodiment, the valve seat 23, valve seat member 21, valve body 13, valve disc support member 19, valve disc 17, and other components are coaxially arranged, and the central axis A1 of these components coincides with the rotation axis of the rotor 43.

[0047] The operation of the motor-operated valve 11 according to this embodiment will be described as follows.

[0048] When a current is supplied to the stator 42 (coil 46) so that the rotor 43 rotates in one direction from the closed valve state shown in Fig. 1, the rotation of the rotor 43 is converted into linear motion by the screw feed mechanism 31, and the screw drive member 33 is pulled upward. As a result, the valve body 17 (head part 17c of the valve body upper part 17b) pressed against the lower surface of the screw drive member 33 via the ball joint 34 by the urging force of the compression coil spring 38 is pulled upward, and the valve body 17 (valve body lower part 17a) is separated from the valve seat 23, and the refrigerant that has flowed in from the first flow tube 15 flows out of the second flow tube 16 through the valve chamber 14 and the through hole 22 (see Fig. 5). The amount of refrigerant passing through in this open valve state (refrigerant flow rate) can be adjusted by the amount of rotation of the rotor 43 (the distance between the valve seat 23 and the valve body 17).

[0049] On the other hand, when a current is supplied to the stator 42 (coil 46) so that the rotor 43 rotates in the opposite direction from the open valve state, the rotation of the rotor 43 is converted into linear motion by the screw feed mechanism 31, and the screw drive member 33 moves downward. With this downward movement, the valve body 17 moves downward, and when the valve body 17 (valve body lower part 17a) abuts against the valve seat 23, the flow path between the first flow path pipe 15 and the second flow path pipe 16 is blocked, and the valve is closed (see FIG. 1).

[0050] In the above operation description, the refrigerant flows in through the first flow path pipe 15 and flows out through the second flow path pipe 16. However, it is also possible to use the motor-operated valve 11 in the opposite manner, so that the refrigerant flows in through the second flow path pipe 16 and flows out through the first flow path pipe 15.

[0051] Second Embodiment Figure 6 shows the joint between the valve body and the valve seat member of a motor-operated valve according to a second embodiment of the present invention, similar to Figure 2. Note that the configuration other than the joint between the valve body and the valve seat member is the same as in the first embodiment, so duplicated explanations will be omitted (the same applies to the third to sixth embodiments described below).

[0052] As shown in FIG. 6, the motor-operated valve of the second embodiment has a positioning portion 24 and a clearance portion 25 in a valve seat member 21, which have the same functions as the motor-operated valve of the first embodiment, and a spiral brazing material flow groove 26 is formed in the positioning portion 24. However, contrary to the first embodiment, the positioning portion 24 is arranged on the lower side (the side closer to the bottom surface of the valve body 13), and the clearance portion 25 is arranged on the upper side (the side closer to the valve chamber 14).

[0053] In this embodiment, only one enlarged diameter portion (see reference symbol 13d) that enlarges the inner diameter of the valve body 13 is required to be formed at the bottom end of the valve body, and the positioning portion 24 is press-fitted into the enlarged diameter portion 13d to position the valve seat member 21 in the radial direction. Note that, similar to the first embodiment, when the positioning portion 24 is press-fitted, the valve seat member 21 can be positioned in the axial direction by abutting the valve seat member 21 against the step portion 13c at the upper end of the enlarged diameter portion 13d.

[0054] On the other hand, in this embodiment, since the clearance portion 25 (joint gap 27) is disposed on the upper side, there is no need to turn the valve body 13 with the valve seat member 21 fitted upside down when brazing, and the brazing material 28 is placed on the valve chamber 14 side (upper end of the joint gap 27). The heated and molten brazing material permeates into the gap (joint gap 27) between the clearance portion 25 and the inner peripheral surface of the valve body 13, flows down the brazing material flow groove 26 formed in the positioning portion 24, and flows out from the bottom side of the valve body 13 (see reference symbol 28a). Therefore, the brazing can be confirmed by visually checking this from the bottom side of the valve body 13 (valve seat member 21).

[0055] Third Embodiment FIG. 7 shows, similarly to FIG. 2, a joint portion between a valve body and a valve seat member of a motor-operated valve according to a third embodiment of the present invention.

[0056] As shown in Figure 7, the motor-operated valve of the third embodiment, like the motor-operated valve of the first embodiment, has a first enlarged diameter portion 13a and a second enlarged diameter portion 13b formed in the valve body 13, and is provided with a positioning portion 24 and a clearance portion 25 in the valve seat member 21, with the positioning portion 24 arranged on the upper side and the clearance portion 25 arranged on the lower side. However, unlike the first embodiment, the brazing material flow groove formed in the positioning portion 24 is a straight groove 71 rather than a spiral groove.

[0057] The linear brazing material flow groove 71 is a groove that extends in the vertical direction along the outer circumferential surface of the valve seat member 21, with its upper end communicating with the valve chamber 14 and its lower end communicating with the joining gap 27 formed by the clearance portion 25. A plurality of such grooves 71 are provided at regular intervals in the circumferential direction of the valve seat member 21.

[0058] In this embodiment, as in the first embodiment, the valve body 13 is turned upside down (so that the bottom surface is on the top and the valve chamber 14 is on the bottom), and the brazing material 28 is placed on the end of the clearance portion 25 (the end of the joint gap 27 on the bottom surface side of the valve body) and melted. The melted brazing material that has permeated the joint gap 27 will pass through the brazing material flow groove 71 and reach the valve chamber 14, so that the brazing material (see symbol 28a in Figure 7) can be visually observed from the valve chamber 14 side to check the brazing material flow.

[0059] [Fourth embodiment] FIG. 8 shows, similarly to FIG. 2, a joint portion between a valve body and a valve seat member of a motor-operated valve according to a fourth embodiment of the present invention.

[0060] As shown in Figure 8, the motor-operated valve of the fourth embodiment, like the motor-operated valve of the first embodiment, is provided with a positioning portion 24 and a clearance portion 25 on a valve seat member 21, with the positioning portion 24 arranged on the upper side and the clearance portion 25 arranged on the lower side. However, unlike the first embodiment, in this embodiment, no step is formed on the inner surface of the valve body 13 facing the boundary portion between the positioning portion 24 and the clearance portion 25.

[0061] According to this embodiment, compared to the first embodiment in which two enlarged diameter portions (first enlarged diameter portion 13a and second enlarged diameter portion 13b) are formed, it is only necessary to form one enlarged diameter portion 13d, thereby reducing the number of processing steps.

[0062] The valve seat member 21 is axially positioned relative to the valve body 13 by abutting the valve seat member 21 against the step 13c.

[0063] Fifth embodiment FIG. 9 shows, similarly to FIG. 2, a joint portion between a valve body and a valve seat member of a motor-operated valve according to a fifth embodiment of the present invention.

[0064] As shown in Figure 9, the motor-operated valve of the fifth embodiment, like the motor-operated valve of the first embodiment, is provided with a positioning portion 24 and a clearance portion 25 on a valve seat member 21, with the positioning portion 24 arranged on the upper side and the clearance portion 25 arranged on the lower side. However, unlike the first embodiment, in this embodiment, an inclined inner circumferential surface 13e is formed on the inner surface of the valve body 13, which gradually narrows in diameter (the inner diameter becomes smaller) as it extends upward, and an inclined outer circumferential surface 24a is formed on the positioning portion 24 of the valve seat member 21, which is inclined in a tapered manner so as to abut against this inclined inner circumferential surface 13e.

[0065] The inclined outer peripheral surface 24a of the valve seat member 21 extends above the inclined inner peripheral surface 13e of the valve body 13 so as to protrude into the valve chamber 14. This is to ensure that the spiral brazing material flow groove 26 formed on the inclined outer peripheral surface 24a to communicate between the clearance portion 25 and the valve chamber 14 reaches the inside of the valve chamber 14.

[0066] According to this embodiment, when the valve seat member 21 is inserted from the opening on the lower surface of the valve body 13 and moved upward, the inclined outer peripheral surface 24a of the valve seat member 21 comes into contact with the inclined inner peripheral surface 13e of the valve body 13 and is inserted in a wedge-like state, so that the valve seat member 21 can be positioned in both the axial direction and the direction perpendicular to the axis. In addition, in the first embodiment, the brazing material flow groove 26 needs to be formed deeper than the step 13c to communicate with the valve chamber 14, but according to this embodiment, the positioning structure is based on the inclined surfaces 13e and 24a instead of the step 13c, and the inclined outer peripheral surface 24a is formed so as to extend upward beyond the inclined inner peripheral surface 13e of the valve body 13 as described above, and the brazing material flow groove 26 is formed on this inclined outer peripheral surface 24a. This has the advantage that the brazing material flow groove 26 can be shallow, making it easier to machine the brazing material flow groove 26.

[0067] Sixth Embodiment FIG. 10 shows, similarly to FIG. 2, a joint portion between a valve body and a valve seat member of a motor-operated valve according to a sixth embodiment of the present invention.

[0068] 10, the motor-operated valve according to the sixth embodiment has an inclined inner peripheral surface 13e and an inclined outer peripheral surface 24a in the positioning portion 24 as in the fifth embodiment, but in addition has a positioning portion similar to that of the first embodiment, that is, an outer peripheral surface (positioning portion 24b) of the valve seat member 21 extending vertically in the same manner as the inner peripheral surface 13f of the valve body 13, which also extends vertically in the vertical direction, pressed against the inner peripheral surface 13f. Note that positioning in the axial direction is performed by the inclined inner peripheral surface 13e and the inclined outer peripheral surface 24a as in the fifth embodiment.

[0069] According to this embodiment, by providing the vertical positioning portion 24b, the support strength of the valve seat member 21 can be increased compared to the fifth embodiment, and it is possible to more reliably prevent the valve seat member 21 from coming off or shifting during, for example, a joining process in which the brazing material is melted in a furnace.

[0070] Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it will be apparent to those skilled in the art that various modifications can be made within the scope of the claims.

[0071] For example, while in each embodiment the valve seat member is configured as a single (integral) part, the valve seat member of the present invention does not necessarily have to be a single part, and the part to be brazed to the valve body and the part that becomes the valve seat may be formed as separate parts and then integrated (e.g., by press fitting, welding, brazing, etc.). [Explanation of symbols]

[0072] a1 Central axis of valve seat material and valve seat A1 Central axis of the valve body and valve element 11 Motor-operated valve 12 Valve section 13 Valve body 13a 1st enlarged diameter section 13b Second enlarged diameter section 13c Step 13d enlarged diameter part 13e Slanted inner surface 13f Vertical inner surface of valve body 14 Valve chamber 15 First flow pipe 16 Second flow pipe 17 Valve body 17a Lower part of valve body 17b Upper part of valve body 17c Head 17d Fitting hole 18 Connecting members 19 Valve body support member 19a Valve body support member body 19b Bottom plate part 19c Cylinder section 21 Valve seat material 22 Through hole 23 Valve seat 24 Positioning part 24a Slanted outer surface 24b Positioning portion (vertical outer peripheral surface of valve seat member) 25 Clearance section 26 Brazing material flow groove (spiral groove) 27 Joint gap 28, 28a Brazing material 31 Transmission mechanism (screw feed mechanism) 32 Bearing materials 32a Female thread 32b insertion hole 33 Screw drive member 33a Male thread 33b Plate-shaped part 34 Ball joint 35 Ball 36 Ball seat 37 Spring support member 37a Bottom plate part 37b Flange part 37c Peripheral wall part 38 Compression coil spring 39 Can 40 Cylindrical member 41 Electric motor (drive unit) 42 Stator 43 Rotor 44 York 45 Bobbin 46 Coil 47 Resin molded cover 48 Rotor parts 49 Support member 50 Shaft 51 Reduction mechanism 52 Sun gear parts 53 Sun Gear 54 Planetary Gear 55 Shaft 56 Career 57 Internal gear 58 Ring gear 59 Output gear 61 Output shaft 61a Fitting groove 71 Brazing material flow groove (straight groove)

Claims

1. a valve body having a valve chamber therein and an opening on a bottom surface; a valve seat member having a communication hole communicating with the valve chest and a valve seat at an end of the communication hole on the valve chest side, the valve seat member being at least partially inserted into the valve body and brazed to the valve body so as to close the opening; a first flow passage pipe communicating with the valve chamber; a second flow passage pipe communicating with the valve chamber via the communication hole; a valve body that moves toward and away from the valve seat to control the amount of fluid passing through; an electric motor that drives the valve body; a transmission mechanism that converts the rotational driving force of the electric motor into linear motion and transmits the linear motion to the valve body; A motor-operated valve comprising: The valve seat member has a portion that is inserted into the valve body. a positioning portion that restricts relative movement between the valve body and the valve seat member in a direction perpendicular to an axis of the valve body; a clearance portion that forms a gap between the inner circumferential surface of the valve body and the inner circumferential surface of the valve body through which a molten brazing material can penetrate; having the positioning portion is disposed on a valve chamber side in an axial direction of the valve body, The clearance portion is disposed on a bottom surface side of the valve body in an axial direction of the valve body, A brazing material flow groove is formed in the outer circumferential surface of the positioning portion, the brazing material flow groove being connected to both the gap and either one of the valve chamber and the bottom surface side exterior of the valve body, and through which molten brazing material can flow. A motor-operated valve.

2. a valve body having a valve chamber therein and an opening on a bottom surface; a valve seat member having a communication hole communicating with the valve chest and a valve seat at an end of the communication hole on the valve chest side, the valve seat member being at least partially inserted into the valve body and brazed to the valve body so as to close the opening; a first flow passage pipe communicating with the valve chamber; a second flow passage pipe communicating with the valve chamber via the communication hole; a valve body that moves toward and away from the valve seat to control the amount of fluid passing through; an electric motor that drives the valve body; a transmission mechanism that converts the rotational driving force of the electric motor into linear motion and transmits the linear motion to the valve body; A motor-operated valve comprising: The valve seat member has a portion that is inserted into the valve body. a positioning portion that restricts relative movement between the valve body and the valve seat member in a direction perpendicular to an axis of the valve body; a clearance portion that forms a gap between the inner circumferential surface of the valve body and the inner circumferential surface of the valve body through which a molten brazing material can penetrate; having a gradually tapering inclined inner circumferential surface of the valve body at a portion of the inner circumferential surface of the valve body into which the valve seat member is inserted; the positioning portion has an inclined outer peripheral surface that abuts against the inclined inner peripheral surface in a wedge shape, A brazing material flow groove is formed in the outer circumferential surface of the positioning portion, the brazing material flow groove being connected to both the gap and either one of the valve chamber and the bottom surface side exterior of the valve body, and through which molten brazing material can flow. A motor-operated valve.

3. The positioning portion is disposed on a bottom surface side of the valve body in an axial direction of the valve body, The clearance portion is disposed on the valve chamber side in the axial direction of the valve body. The motor-operated valve according to claim 2.

4. The brazing material flow groove is a spiral groove that extends in a spiral shape on the outer circumferential surface of the positioning portion. The motor-operated valve according to claim 1 or 2.

5. The brazing material flow groove is a linear groove extending parallel to an axis of the valve body, The linear groove is provided with one or more The motor-operated valve according to claim 1 or 2.

6. The valve body has a positioning step portion that restricts movement of the valve seat member in the axial direction of the valve body. The motor-operated valve according to claim 1 or 2.

7. a gradually tapering inclined inner circumferential surface of the valve body at a portion of the inner circumferential surface of the valve body into which the valve seat member is inserted; The positioning portion has an inclined outer peripheral surface that abuts against the inclined inner peripheral surface in a wedge shape. The motor-operated valve according to claim 1.

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