Electric valve and refrigeration cycle system

Abstract

To provide a motor-operated valve capable of suppressing vibration of a valve element, and a refrigeration cycle system.SOLUTION: A motor-operated valve 1 includes a valve body 10 having a valve chest 11, a flow passage member 50 fixed in the valve chest 11, and a valve element 40 moving inside the flow passage member 50 in an axial line L direction. The flow passage member 50 includes a connection portion 51, an extension portion 52 continuous with the connection portion 51, a guide hole 55 penetrating the extension portion 52 in the axial line L direction, and a communication hole 54 penetrating a side surface of the extension portion 52. The valve element 40 includes a straight portion 41 inserted into the guide hole 55, a needle portion 42, and a connecting portion 43 serving as a boundary between the straight portion 41 and the needle portion 42. A throttle S is formed between an outer peripheral surface of the valve element 40 and an inner peripheral surface of the guide hole 55, and the valve element 40 is moved in the axial line L direction in a state where the connecting portion 43 is overlapped with the communication hole 54 so that an opening size of the throttle S is variable.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a motor-operated valve and a refrigeration cycle system. [Background technology]

[0002] This motor-operated valve includes a valve body defining a valve chamber therein, a valve seat provided in the valve body to define a valve port, a valve element (needle valve) for adjusting the valve port's opening, a drive unit for axially driving the valve element back and forth, and a support member that, together with the drive shaft of the drive unit, constitutes a screw feed mechanism. The valve body is provided with a primary coupling pipe connected to its side for introducing fluid into the valve chamber, and a secondary coupling pipe connected to the bottom of the valve body for discharging fluid from the valve port (see Patent Document 1). The valve plenum (valve chamber) of the variable expansion valve described in Patent Document 1 includes a cylindrical positioning cover that is continuous with the valve port base (valve seat) and guides a needle valve unit (a needle valve) in the axial direction. The positioning cover has a coolant port penetrating its peripheral wall. The fluid that flows into the positioning cover through the coolant port flows out to the outlet tube (secondary coupling pipe) at a reduced flow rate in the gap between the tip (needle portion) of the needle valve unit and the inner periphery of the valve port. In this way, conventional motor-operated valves are used as expansion valves in which a throttle portion is formed that throttles the fluid by the gap between the needle portion and the valve port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Mito 3193049 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a configuration such as the above-mentioned variable expansion valve, the fluid that flows into the positioning cover from the coolant port collides with the side of the needle valve unit, which can cause the needle valve unit to vibrate and generate noise.

[0005] An object of the present invention is to provide an electrically operated valve and a refrigeration cycle system that can suppress vibration of a valve element. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the object, the motor-operated valve of the present invention is a motor-operated valve comprising: a valve body having a valve chamber therein and a B port that opens to the bottom surface of the valve chamber; a flow path member fixed within the valve chamber; and a valve element provided within the flow path member so as to be movable in the axial direction, wherein the flow path member comprises a connection part that communicates with the B port and is fixed to the valve body; an extension part that is continuous with the connection part and extends in the opposite direction to the B port; a guide hole that penetrates the extension part in the axial direction and has a constant diameter; a communicating hole penetrating the valve surface and communicating the valve chamber with the guide hole, the valve body having a straight portion that is inserted into the guide hole and has a constant diameter, a needle portion that tapers in diameter continuing to the tip side of the straight portion, and a boundary portion that is a boundary between the straight portion and the needle portion, a throttling portion is formed between the outer peripheral surface of the valve body and the inner peripheral surface of the guide hole, and the valve body moves in the axial direction with the boundary portion overlapping the communicating hole, thereby making it possible to change the opening size of the throttling portion.

[0007] According to the present invention, by inserting the straight portion of the valve disc into the guide hole and moving it axially while the boundary between the straight portion and the needle portion overlaps the communicating hole, the inner circumferential surface of the guide hole can guide the portion of the valve disc from the side opposite the needle portion to the portion immediately adjacent to the needle portion. As a result, when fluid passes through the throttle portion between the outer circumferential surface of the valve disc and the inner circumferential surface of the guide hole, the portion of the valve disc that is closest to the throttle portion is guided by the guide hole, and this guide hole can suppress vibration of the valve disc. Therefore, an electric valve that suppresses vibration of the valve disc can be obtained.

[0008] In this case, it is preferable that a resin surface portion made of resin is provided on the inner peripheral surface of the guide hole at least in a range spanning the communicating hole in the axial direction. In the present invention, since the flow path member is fixed inside the valve chamber (valve body), the guide hole stably guides the valve disc. However, since the flow path member is fixed to the valve body, the sliding resistance between the inner peripheral surface of the guide hole and the outer peripheral surface of the valve disc is likely to be large. Therefore, wear may occur due to sliding between the inner peripheral surface of the guide hole and the outer peripheral surface of the valve disc. This wear may generate wear debris and reduce the durability of the motor-operated valve. Furthermore, this wear may cause dimensional changes in the throttling portion between the outer peripheral surface of the valve disc and the inner peripheral surface of the guide hole, which may cause the flow rate of the fluid passing through the throttling portion to become unstable. However, according to this configuration, by providing a resin surface portion on at least a range spanning the communicating hole in the axial direction on the inner peripheral surface of the guide hole, the slidability of the valve disc, particularly near the communicating hole, can be improved. This reduces the wear and improves the durability of the motor-operated valve. Furthermore, since wear is less likely to occur between the valve body and the guide hole, dimensional changes in the throttle portion are suppressed, and the flow rate of the fluid passing through the throttle portion can be stabilized.

[0009] Furthermore, it is preferable that the flow path member is an integrally molded part made of resin. With this configuration, the flow path member including the connecting portion and the extension portion can be integrally molded, which simplifies the components of the motor-operated valve and makes it easy to assemble the motor-operated valve.

[0010] Furthermore, it is preferable that at least the outer peripheral surface of the straight portion of the valve body is provided with a resin surface portion made of resin. With this configuration, the portion of the valve body that slides against the inner peripheral surface of the guide hole is made of resin, which further improves the slidability of the valve body, suppresses the above-mentioned wear, and improves the durability of the motor-operated valve. Furthermore, by reducing the likelihood of wear between the valve body and the guide hole, dimensional changes in the throttle portion between the outer peripheral surface of the valve body and the inner peripheral surface of the guide hole are suppressed, and the flow rate of the fluid passing through the throttle portion can be further stabilized.

[0011] Preferably, the valve further includes a drive unit having a drive shaft connected to the valve element, and a support member fixed to the valve body and having an insertion hole through which the drive shaft passes, wherein a screw feed mechanism is formed by a male threaded portion provided on one side of the drive unit and the support member and a female threaded portion provided on the other side, the guide hole and the insertion hole are coaxially continuous, and the flow path member is fixed to the support member. With this configuration, the flow path member can be fixed to the valve body via the support member, so that even if the valve element attempts to vibrate within the guide hole, the vibration can be stably suppressed and maintained. Therefore, the valve element can be stably guided by the guide hole.

[0012] Furthermore, it is preferable that the support member and the flow path member are integrally formed. With this configuration, the flow path member and the support member can be integrally formed, simplifying the components of the motor-operated valve and facilitating assembly of the motor-operated valve. Furthermore, with this configuration, the flow path member and the support member do not become misaligned with each other, ensuring that the guide hole of the flow path member and the insertion hole of the support member are coaxial, thereby reducing sliding resistance between the outer peripheral surface of the valve body and the inner peripheral surface of the guide hole.

[0013] Furthermore, it is preferable that the connection portion of the flow path member is formed in a cylindrical shape and is inserted and fixed into the port B. According to this configuration, the flow path member can be fixed to the valve body by inserting and fixing the connection portion of the flow path member into the port B, which makes it easy to fix the flow path member.

[0014] Furthermore, it is preferable that a space be formed between the tip of the connection portion of the flow path member and the end face of the piping connected to the B port. In a motor-operated valve, a piping through which a fluid flows is sometimes installed in the B port. The end of this piping is inserted into the B port and fixed by brazing or the like. In this case, a fillet of brazing material is formed at the corner formed by the inner circumferential surface of the B port and the end face of the piping. The fillet portion may get in the way, making it difficult to install the connection portion of the flow path member in the B port, or the connection portion may be fixed at an unintended angle. However, with this configuration, by forming a space between the tip of the connection portion of the flow path member and the end face of the piping, the fillet can be contained within the space, and the flow path member can be stably fixed within the valve chamber without being affected by the fillet.

[0015] Furthermore, it is preferable that the valve body includes an A port that opens to a side surface of the valve chamber, and that the fluid that flows into the valve chamber from the A port flows through the communication hole, passes through the throttle section, and then flows to the B port, and that the communication hole is located in a non-opposing position that does not face the A port. This configuration prevents the fluid that flows into the valve chamber from the A port from proceeding linearly to the communication hole in the same direction as the flow and directly colliding with the valve disc. In other words, the fluid that flows in from the communication hole can first collide with the outer surface of the flow path member, thereby absorbing the impact, and then enter the communication hole. This reduces the force applied to the valve disc, thereby suppressing vibration of the valve disc.

[0016] Furthermore, it is preferable that the communication hole be formed in a circular shape when viewed from the through direction, have a uniform flow path cross-sectional area, which is the opening area when cut in a direction perpendicular to the flow direction of the fluid flowing therethrough, and the length from the opening on the valve chamber side to the opening on the guide hole side is equal to or greater than the inner diameter. With this configuration, the fluid flowing through a communication hole with a length in the through direction equal to or greater than the inner diameter and a uniform flow path cross-sectional area has a constant flow rate and constant pressure, thereby stabilizing the flow of the fluid from the valve chamber toward the throttle section. In other words, the communication hole can achieve a fluid rectification effect.

[0017] The refrigeration cycle system of the present invention includes a compressor, a condenser, an expansion valve, and an evaporator, and is characterized in that the motor-operated valve according to claim 1 is used as the expansion valve. With this configuration, the refrigeration cycle system can be configured using the motor-operated valve capable of suppressing vibration of the valve body as the expansion valve. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a motor-operated valve and a refrigeration cycle system that can suppress vibration of the valve element. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view taken along the axial direction of a motor-operated valve according to a first embodiment of the present invention. [Figure 2] FIG. 3 is an enlarged cross-sectional view of the motor-operated valve taken along the axial direction. [Figure 3] FIG. 4 is a partially enlarged cross-sectional view of the motor-operated valve taken along the axial direction, with the valve element positioned at the lowest position. [Figure 4] 4 is a partially enlarged cross-sectional view taken along the axial direction of the motor-operated valve, showing a state in which the valve element has risen from the state shown in FIG. 3. [Figure 5] 5 is a partially enlarged cross-sectional view taken along the axial direction of the motor-operated valve, showing a state in which the valve element has risen from the state shown in FIG. 4. [Figure 6] 10A and 10B are diagrams showing variations in the structure of a flow path member that constitutes a motor-operated valve. [Figure 7] 10(A) to 10(C) are diagrams showing variations in the arrangement of communication holes in a flow path member. [Figure 8] 10A to 10C are diagrams showing variations in the arrangement of communication holes in the flow path member. [Figure 9] 10A to 10C are diagrams showing variations in the arrangement of communication holes in the flow path member. [Figure 10] FIG. 10 is a cross-sectional view taken along the axial direction of a flow path member according to a first modified example of the first embodiment. [Figure 11] FIG. 10 is a cross-sectional view taken along the axial direction of a flow path member according to a second modified example of the first embodiment. [Figure 12] FIG. 10 is a cross-sectional view taken along the axial direction of the motor-operated valve according to the second embodiment. [Figure 13] 1 is a diagram showing an example of a refrigeration cycle system according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] A first embodiment of the present invention will be described below with reference to Figures 1 to 9. Note that the concept of "upper and lower" in the following description corresponds to the upper and lower in Figure 1, but this is for the sake of convenience of description only and does not necessarily coincide with the upper and lower in the actual use state of the motor-operated valve 1, and does not limit the directions in the actual use state of the motor-operated valve 1. As shown in Figure 1, the motor-operated valve 1 includes a valve body 10, a support member 20, a drive unit 30, a valve element 40, and a flow path member 50.

[0021] The valve body 10 is formed in a generally cylindrical shape using a metal material such as brass or stainless steel, and has a valve chamber 11 inside. A port A 13 is formed in a side wall 12 (side surface) of the valve body 10, penetrating radially, and a first coupling pipe 14, which serves as a pipe for a refrigerant (fluid), is inserted into the side wall 12. The first coupling pipe 14 is fixed to the valve body 10 by brazing or the like, and its interior communicates with the valve chamber 11. A bottom wall 15 (bottom surface) is formed at the lower end of the side wall 12, extending radially inward, and a small-diameter portion 16 is formed in the center of the bottom wall 15, protruding downward and opening in the direction of the axis L of the valve body 10.

[0022] The opening of the small diameter portion 16 communicates with the valve chamber 11 and forms a B port 17. That is, the valve body 10 is provided with the B port 17, which opens in the bottom wall 15. A second coupling pipe 18, which serves as a refrigerant pipe, is inserted into the B port 17. The second coupling pipe 18 is fixed to the valve body 10 by brazing or the like, and its interior communicates with the valve chamber 11. A case 19, which is formed in a cylindrical shape with a bottom, is airtightly fixed to the upper end of the side wall 12 by welding or the like at its open end. A cylindrical support portion 19a, which protrudes downward along the axis L and opens downward, is formed in the center of the bottom of the case 19 (in FIG. 1, this portion corresponds to the inner surface of the upper end of the motor-operated valve 1). An upper portion 34a of a drive shaft 34, which will be described later, is inserted into the support portion 19a.

[0023] The support member 20 is a member that supports the drive shaft 34 within the valve chamber 11 and includes a press-fit portion 21 that is press-fitted into the upper end opening of the valve body 10, a holder portion 22 that is disposed above the press-fit portion 21, an insertion hole 23 that passes through the centers of the press-fit portion 21 and the holder portion 22, and a flange portion 24 that is formed integrally with the press-fit portion 21 by insert molding. The press-fit portion 21 is formed in a cylindrical shape from a resin material. A mounting recess 25 that is recessed in the direction of the axis L is formed on the underside of the press-fit portion 21, and the upper end of the flow path member 50 is fixed to the mounting recess 25. The holder portion 22 is molded integrally with the press-fit portion 21 from a resin material. The holder portion 22 is formed with a smaller diameter than the press-fit portion 21 and extends upward along the axis L from the center of the press-fit portion 21.

[0024] The insertion hole 23 is a hole through which the drive shaft 34 is inserted, and is composed of a large-diameter first insertion hole 23a formed in the center of the holder portion 22 and a small-diameter second insertion hole 23b formed in the center of the press-fit portion 21 and communicating with the first insertion hole 23a. An internal thread portion 26 that threadably mates with an external thread portion 35 (described later) is formed on the inner circumferential surface of the first insertion hole 23a. The upper end side of a straight portion 41 of a valve body 40 (described later) is inserted into the second insertion hole 23b. The flange portion 24 is formed in an annular shape from a metal material, protrudes radially outward from the press-fit portion 21, and is fixed to the upper end of the side wall 12 of the valve body 10 by welding.

[0025] The drive unit 30 includes a stepping motor 31 and a stopper mechanism 32 that restricts rotation of the stepping motor 31. The stepping motor 31 is composed of a magnet rotor 33 arranged within the case 19, a stator coil (not shown) that is installed outside the case 19 and circumferentially covers the magnet rotor 33, a drive shaft 34 that is attached to the magnet rotor 33 via a bushing installed in the center of the magnet rotor 33, and other components (not shown), such as a yoke and exterior members. The magnet rotor 33 includes a lower cylindrical portion 33a that extends downward and covers the holder portion 22, and an upper cylindrical portion 33b that extends upward and covers the support portion 19a. The magnet rotor 33 is provided to be rotatable about the axis L and movable in the direction of the axis L. The drive shaft 34 has an upper portion 34a that extends upward from the magnet rotor 33 along the axis L and is inserted into the support portion 19a, and a lower portion 34b that extends downward from the magnet rotor 33 along the axis L and into the first insertion hole 23a.

[0026] A male threaded portion 35 that screws together with the female threaded portion 26 formed on the holder portion 22 is formed in a portion of the lower portion 34b that is located inside the first insertion hole 23a. With this screw engagement, the drive shaft 34 is supported by the support member 20 inside the valve chamber 11. In this embodiment, when the magnet rotor 33 rotates around the axis L, the male threaded portion 35 is screwed and the magnet rotor 33 and the drive shaft 34 move in the direction of the axis L. In other words, the male threaded portion 35 provided on one of the support member 20 and the drive portion 30 and the female threaded portion 26 provided on the other constitute a screw feed mechanism A.

[0027] The stopper mechanism 32 includes a cylindrical portion 36 that circumferentially covers the outer peripheral surface of the support portion 19a described above, a guide portion 37 that forms a spiral groove on the outer peripheral surface of the cylindrical portion 36, and a coil-shaped slider 38 that screws into the guide portion 37. The slider 38 includes claw portions 39 that protrude radially outward. The claw portions 39 are capable of abutting against the radially inner edge of the upper cylindrical portion 33b of the magnet rotor 33 around the axis L. As a result, when the magnet rotor 33 rotates, the slider 38 rotates in response to the rotation, and the slider 38 is guided by the guide portion 37 to move upward or downward. When the slider 38 abuts against the upper or lower end of the guide portion 37, it is unable to rotate any further, and the rotation of the magnet rotor 33 is forcibly stopped.

[0028] The valve element 40 is continuous with the lower end of the lower portion 34b of the drive shaft 34, extends along the axis L, is inserted into the second insertion hole 23b, and protrudes downward from the support member 20. The valve element 40 is rotatable around the axis L within the flow path member 50 and is movable in the direction of the axis L. The valve element 40 includes a straight portion 41 that is continuous with the lower end of the lower portion 34b of the drive shaft 34, and a needle portion 42 that is continuous with the lower end (tip) of the straight portion 41. The straight portion 41 is a portion that is inserted into a guide hole 55 of the flow path member 50, which will be described later, and has a diameter (diameter) that is approximately the same as the inner diameter of the guide hole 55, and the diameter is constant in the direction of the axis L.

[0029] The needle portion 42 includes a maximum diameter portion 42a connected to the lower end of the straight portion 41, a first needle portion 42b connected to the maximum diameter portion 42a, a second needle portion 42c connected to the first needle portion 42b, and a third needle portion 42d connected to the second needle portion 42c. The diameter of the maximum diameter portion 42a is set to be the same as the diameter of the lower end of the straight portion 41, and is the largest diameter of the needle portion 42. The diameter of the first needle portion 42b gradually decreases as it extends downward from the maximum diameter portion 42a. The diameter of the second needle portion 42c gradually decreases as it extends downward from the first needle portion 42b.

[0030] The third needle portion 42d is formed so that its diameter gradually decreases as it extends downward from the second needle portion 42c. In this way, the needle portion 42 is formed so that its diameter (radial dimension) tapers continuously from the lower end (tip side) of the straight portion 41. The joint between the lower end of the straight portion 41, which has the same diameter, and the maximum diameter portion 42a of the needle portion 42 constitutes a joint 43 (boundary portion) that serves as a boundary between the straight portion 41 and the needle portion 42. The joint between the first needle portion 42b and the second needle portion 42c constitutes a second joint 44, and the joint between the second needle portion 42c and the third needle portion 42d constitutes a third joint 45.

[0031] The flow path member 50 is a component that constitutes a flow path for refrigerant that flows between the A port 13 and the B port 17. The flow path member 50 is formed into a cylindrical shape, for example, from a resin integrally molded component or the like, and is fixed inside the valve chamber 11. The flow path member 50 includes a connection portion 51 that communicates with the B port 17 and is fixed to the valve body 10, an extension portion 52 that is continuous with the connection portion 51 and extends upward (toward the opposite side from the B port 17) along the axis L, and a through-hole 53 that passes through the centers of the connection portion 51 and the extension portion 52 in the direction of the axis L. The connection portion 51 is formed into a cylindrical shape and is inserted and fixed into the B port 17, with its lower end (tip) abutting against the upper end surface of the second joint pipe 18. The connection portion 51 can be fixed by, for example, press-fitting into the B port 17, or by any suitable method such as welding or deposition.

[0032] The extension portion 52 is cylindrical and extends upward along the axis L from the upper end of the connection portion 51. Its upper end is fixed to the mounting recess 25 of the support member 20. A communication hole 54 is formed in the extension portion 52. The communication hole 54 penetrates from the side surface of the extension portion 52 to the inner circumferential surface of a guide hole 55 (described later) and extends in a direction perpendicular to the axis L. The communication hole 54 communicates between the valve chamber 11 and the guide hole 55. In this embodiment, the communication hole 54 is circular when viewed from the direction of penetration and has a constant inner diameter. However, the shape of the communication hole 54 is not limited thereto. For example, the communication hole 54 may be elliptical or oval when viewed from the direction of penetration, or may be tapered so that the inner diameter differs between one side and the other side in the direction of penetration. The communication hole 54 may also be a notch that opens in the direction of the axis L. In addition, when the communicating hole 54 is formed in a circular shape when viewed from the penetration direction and the inner diameter dimension is set to be constant, as in the present embodiment (i.e., when the flow path cross-sectional area, which is the opening area when the communicating hole 54 is cut in a direction perpendicular to the flow direction of the fluid flowing inside, is uniform), from the perspective of stabilizing the flow of fluid flowing from the valve chamber 11 into the flow path member 50, it is more preferable that the length of the communicating hole 54 from the opening edge (opening) on ​​the valve chamber 11 side to the opening edge (opening) on ​​the guide hole 55 side (i.e., the length in the penetration direction) is equal to or greater than the inner diameter.

[0033] The through hole 53 is formed at a position where its central axis is coaxial with the insertion hole 23 of the support member 20, and is equipped with a guide hole 55 that communicates with the insertion hole 23 and extends in the direction of axis L, and a connection hole 56 that communicates with the guide hole 55, extends in the direction of axis L, and communicates with the B port 17. As shown in Figures 2 and 3, the guide hole 55 is formed to have the smallest inner diameter of the through hole 53, and is formed so that the opening areas of an upper end opening 55a that opens at the upper end, a lower end opening 55b that opens at the lower end, and the opening area of ​​the portion extending from the upper end opening 55a to the lower end opening 55b are constant. In other words, the guide hole 55 is formed to have a constant diameter while penetrating the extension portion 52 in the direction of axis L.

[0034] The outer peripheral surface of the straight portion 41 of the valve body 40 can abut against the inner peripheral surface of the guide hole 55, and as a result, the inner peripheral surface of the guide hole 55 forms a guide portion that guides movement of the straight portion 41 in the direction of the axis L. Note that, from the viewpoint of appropriately guiding the straight portion 41 while suppressing displacement of the straight portion 41 in a direction intersecting the direction of the axis L, it is preferable that the clearance D (shown only in FIG. 3; inner diameter dimension of the guide hole 55 - outer diameter dimension of the straight portion 41) between the outer peripheral surface of the straight portion 41 and the inner peripheral surface of the guide hole 55 is set to approximately 0.005 to 1 mm. Note that, for ease of explanation, in FIGS. 3 to 5, the clearance D between the outer peripheral surface of the straight portion 41 and the inner peripheral surface of the guide hole 55 is depicted larger than it actually is, but the actual clearance D is within the set range described above. The connecting hole 56 extends in the direction of the axis L, has an upper end communicating with the lower end opening 55b of the guide hole 55, and a lower end communicating with the B port 17. The inner diameter of the connecting hole 56 is set larger than the inner diameter of the guide hole 55. With this configuration, the valve chest 11 and the B port 17 are communicated with each other via the valve chest 11, the communicating hole 54, and the through hole 53, and the fluid that flows into the valve chest 11 from the A port 13 flows from the communicating hole 54 through the through hole 53 to the B port 17.

[0035] In the motor-operated valve 1 configured as described above, when the stepping motor 31 is driven, the magnet rotor 33 rotates about the axis L, and the male thread portion 35 is threadedly fed by the screw feed mechanism A, causing the magnet rotor 33 and the drive shaft 34 to move back and forth along the axis L within a range in which displacement is restricted by the stopper mechanism 32. At this time, as shown in FIGS. 3 to 5, the straight portion 41 of the valve element 40 moves along the axis L while being guided by the inner circumferential surface of the guide hole 55 of the flow path member 50. Then, the flow rate of the refrigerant flowing from the A port 13 to the valve chamber 11, the communication hole 54, the through hole 53 (the guide hole 55, the connection hole 56), and the B port 17 decreases from the lower end 54a of the guide hole 55 on the opening edge of the communication hole 54 on the guide hole 55 side to the lower end opening 55b, as shown in FIG. That is, a throttle portion S is formed between the outer peripheral surface of the valve body 40 and the inner peripheral surface of the guide hole 55 to reduce the flow rate of the refrigerant flowing from the communication hole 54 toward the B port 17 .

[0036] As shown in FIG. 3 , the opening size of the throttle portion S is determined by the cross-sectional area of ​​an annular portion between the inner diameter of the guide hole 55 and the outer diameter of the valve element 40 in a cross section taken along line AA of the flow path member 50, which is cut perpendicular to the axis L at the lower end 54a of the opening edge of the communicating hole 54 on the guide hole 55 side. In the motor-operated valve 1 shown in FIG. 3 , the valve element 40 is positioned at its lowest position. In this state, the connecting portion 43 of the valve element 40 is positioned below the lower end 54a of the communicating hole 54, and with the straight portion 41 guided by the guide hole 55, the throttle portion S is formed between the lower end 54a of the communicating hole 54 and the straight portion 41. In this state, the opening size of the throttle portion S is the smallest, a first opening size S1. When the valve element 40 is raised from this state, the throttle portion S is formed between the lower end 54a of the communicating hole 54 and the first needle portion 42b, as shown in FIG. 4 . As described above, the diameter of the first needle portion 42b decreases as it extends downward from the connecting portion 43, so in this state the opening size of the throttling portion S is the second opening size S2, which is larger than the first opening size S1.

[0037] When the valve disc 40 rises from this state, as shown in FIG. 5 , a throttle section S is formed between the lower end 54a of the communicating hole 54 and the second needle section 42c. As described above, the diameter of the second needle section 42c decreases downward from the first needle section 42b. Therefore, in this state, the opening size of the throttle section S becomes a third opening size S3, which is larger than the second opening size S2. That is, when the connecting section 43 is located below the lower end 54a of the communicating hole 54, the opening size of the throttle section S is constant at the first opening size S1. As the valve disc 40 moves in the direction of the axis L with the connecting section 43 overlapping the communicating hole 54, the opening size of the throttle section S is variable in multiple stages so as to become a predetermined opening size for the lift amount of the valve disc 40. With this configuration, fluid that flows into the valve chamber 11 from the A port 13 passes through the communicating hole 54 and the throttle section S, whose opening size is variable, before flowing to the B port 17.

[0038] The opening sizes of the throttle section S in this embodiment (first opening size S1, second opening size S2, and third opening size S3) are merely examples, and can be varied in any number of stages by changing the shape of the needle section 42, etc. Furthermore, if the clearance between the straight section 41 and the guide hole 55 is set to approximately zero, the opening size of the throttle section S can be made close to zero. In other words, the opening size of the throttle section S can be varied in multiple stages from zero or more. Furthermore, if the valve disc 40 is displaced to the uppermost position opposite the lowermost position, the lower end of the needle section 42 can be configured not to overlap with the communicating hole 54 in the direction through which the communicating hole 54 penetrates. In this case, however, it is preferable to set the opening area of ​​the guide hole 55 smaller than the opening area of ​​the communicating hole 54 in order to reduce the flow rate of fluid from the communicating hole 54 toward the B port 17.

[0039] Next, the refrigeration cycle system of the present invention will be described with reference to Fig. 13. Fig. 13 is a diagram showing an example of a refrigeration cycle system of the present invention. In Fig. 13, reference numeral 1 denotes an expansion valve using the motor-operated valve 1, 200 denotes an outdoor heat exchanger mounted in an outdoor unit, 300 denotes an indoor heat exchanger mounted in an indoor unit, 400 denotes a flow path switching valve constituting a four-way valve, and 500 denotes a compressor. The motor-operated valve 1 (expansion valve), outdoor heat exchanger 200, indoor heat exchanger 300, flow path switching valve 400, and compressor 500 are each connected by conduits as shown in the figure to constitute a heat pump type refrigeration cycle. Note that an accumulator, pressure sensor, temperature sensor, etc. are not shown.

[0040] The flow path of the refrigeration cycle is switched by flow path switching valve 400 between two flow paths: one for cooling operation and one for heating operation. During cooling operation, as shown by the solid arrows in Fig. 13, refrigerant compressed by compressor 500 flows through flow path switching valve 400 into outdoor heat exchanger 200, which functions as a condenser, and liquid refrigerant flowing out of outdoor heat exchanger 200 flows through motor-operated valve 1, which functions as an expansion valve, into indoor heat exchanger 300, which functions as an evaporator. On the other hand, during heating operation, as shown by the dashed arrows in Fig. 13, refrigerant compressed by compressor 500 circulates from flow path switching valve 400 to indoor heat exchanger 300, motor-operated valve 1, which functions as an expansion valve, outdoor heat exchanger 200, and compressor 500 in that order, with indoor heat exchanger 300 functioning as a condenser and outdoor heat exchanger 200 functioning as an evaporator.

[0041] According to the above-described embodiment, the straight portion 41 of the valve element 40 is inserted through the guide hole 55, and the connecting portion 43 (boundary portion) between the straight portion 41 and the needle portion 42 is moved in the axial direction L while overlapping the communicating hole 54. This allows the inner circumferential surface of the guide hole 55 to guide the portion of the valve element 40 from the opposite side of the needle portion 42 (the upper portion of the straight portion 41) to the portion immediately adjacent to the needle portion 42. As a result, when fluid passes through the throttle portion S between the outer circumferential surface of the valve element 40 and the inner circumferential surface of the guide hole 55, the portion of the valve element 40 closest to the throttle portion S is guided by the guide hole 55, and the guide hole 55 can suppress vibration of the valve element 40. Therefore, an electrically operated valve 1 capable of suppressing vibration of the valve element 40 can be obtained. Furthermore, a refrigeration cycle system can be configured using the electrically operated valve 1 capable of suppressing vibration of the valve element 40 as an expansion valve.

[0042] Furthermore, since the flow path member 50 is an integrally molded part made of resin, the flow path member 50 having the connection portion 51 and the extension portion 52 can be molded as a single unit, simplifying the components of the electric valve 1 and making it easy to assemble the electric valve 1.

[0043] Furthermore, in the first embodiment, the flow path member 50 is configured such that the upper end of the extension portion 52 is fixed to the mounting recess 25 of the support member 20, and the guide hole 55 and the insertion hole 23 are coaxially continuous. With this configuration, the flow path member 50 is fixed to the valve body 10 via the support member 20, so that even if the valve element 40 attempts to vibrate within the guide hole 55, the vibration can be stably suppressed and maintained in a suppressed state. Therefore, the valve element 40 can be stably guided by the guide hole 55.

[0044] Furthermore, the connection portion 51 of the flow path member 50 is formed in a cylindrical shape and is inserted and fixed into the B port 17. With this configuration, the flow path member 50 can be fixed to the valve body 10 by inserting and fixing the connection portion 51 of the flow path member 50 into the B port 17, making it easy to fix the flow path member 50. As a result, the flow path member 50 is directly fixed to the valve body 10 at the connection portion 51, and is fixed to the valve body 10 via the support member 20 at the extension portion 52, so that one side and the other side in the direction of the axis L are fixed to the valve body 10. This makes it possible to more stably maintain a state in which vibration of the valve disc 40 is suppressed.

[0045] Furthermore, when the communicating hole 54 is formed in a circular shape as viewed from the through-hole direction, the flow path cross-sectional area, which is the opening area when cut in a direction perpendicular to the flow direction of the fluid flowing inside, is made uniform, and the length in the through-hole direction is made equal to or greater than the inner diameter, thereby making it possible to keep the flow rate of the fluid flowing inside constant and the pressure of the fluid constant. This makes it possible to stabilize the flow of fluid from the valve chamber 11 toward the throttle section S. In other words, the communicating hole 54 can achieve a fluid rectification effect.

[0046] The above describes in detail the embodiments of the electric valve 1 with reference to the drawings, but the specific configuration is not limited to these embodiments, and the present invention also includes design changes within the scope of the present invention that do not deviate from the gist of the present invention.

[0047] 6(A) and 6(B) are diagrams showing variations in the structure of a flow path member 50 constituting the motor-operated valve 1. A cylindrical inner cylinder portion 60 is fitted into a connection hole 56 in a through hole 53 of the flow path member 50 shown in FIG. 6(A). The inner cylinder portion 60 is formed using a resin material such as PPS (polyphenylene sulfide) or PEEK (polyether ether ketone). The outer diameter of the inner cylinder portion 60 is set to be the same as the inner diameter of the connection hole 56, thereby fitting the inner cylinder portion 60 into the connection hole 56. A second communication hole 61 communicating with the communication hole 54 and a second guide hole 62 communicating with the guide hole 55 are formed in the inner cylinder portion 60. The second communication hole 61 is formed through the side wall of the inner cylinder portion 60, with an opening on one side in the penetration direction communicating with the communication hole 54 and an opening on the other side in the penetration direction communicating with the second guide hole 62. A lower end 61a of the opening edge of the second communicating hole 61 on the second guide hole 62 side has the same function as the lower end 54a of the opening edge of the communicating hole 54 in the first embodiment, and corresponds to this lower end 54a. The second guide hole 62 has the same inner diameter as the guide hole 55, is coaxial with the guide hole 55, and penetrates in the direction of the axis L, and its inner circumferential surface forms a guide portion for the valve body 40, similar to the guide hole 55. The second guide hole 62 has the same function as the guide hole 55, and a lower end opening 62a of the second guide hole 62 corresponds to the lower end opening 55b in the first embodiment.

[0048] A resin-made cylindrical long-axis inner cylinder portion 70 is fitted inside the through-hole 53 of the flow path member 50 shown in FIG. 6B, extending downward in the axial direction L from an opening at the upper end. The long-axis inner cylinder portion 70 is formed using a resin material such as PPS (polyphenylene sulfide) or PEEK (polyether ether ketone). The long-axis inner cylinder portion 70 is formed with a third communication hole 71 that communicates with the communication hole 54 and a third guide hole 72 that penetrates in the axial direction L. The third communication hole 71 has the same function as the communication hole 54 and the second communication hole 61 described above, and a lower end 71a of the opening edge on the third guide hole 72 side corresponds to the lower end 54a of the communication hole 54 and the lower end 61a of the second communication hole 61. Unlike the first embodiment and the like, the third guide hole 72 independently constitutes a guide hole (guide portion). The upper end opening 72a of the third guide hole 72 corresponds to the upper end opening 55a in the first embodiment, and the lower end opening 72b corresponds to the lower end opening 55b in the first embodiment. As a result, the range of the inner circumferential surface of the guide hole (the inner circumferential surface of the second guide hole 62 or the third guide hole 72) that straddles the communication hole 54 in the direction of the axis L is formed of a resin surface portion.

[0049] According to this configuration, the area of ​​the inner circumferential surface of the guide hole (the inner circumferential surface of the second guide hole 62 or the third guide hole 72) that spans the communication hole 54 in the axial direction L is made of a resin surface, thereby improving the slidability of the valve element 40. In the motor-operated valve 1, the flow path member 50 is fixed inside the valve chamber 11 (valve body 10), so that the guide hole 55 stably guides the valve element 40. However, because the flow path member 50 is fixed inside the valve chamber 11, the sliding resistance between the inner circumferential surface of the guide hole 55 and the outer circumferential surface of the valve element 40 tends to increase, and wear may occur due to the sliding between the inner circumferential surface of the guide hole 55 and the outer circumferential surface of the valve element 40. This may result in the generation of wear debris, which may reduce the durability of the motor-operated valve 1.

[0050] Furthermore, the wear described above may cause dimensional changes in the throttle section S between the outer peripheral surface of the valve body 40 and the inner peripheral surface of the guide hole 55, which may result in an unstable flow rate of the fluid passing through the throttle section S. However, according to the present configuration, the range of the inner peripheral surface of the guide hole (the inner peripheral surface of the second guide hole 62 or the third guide hole 72) spanning the communication hole 54 in the axial direction L is made of a resin surface, which improves the sliding properties of the valve body 40 and thereby suppresses the above-mentioned wear. This improves the durability of the motor-operated valve 1. Furthermore, since wear is less likely to occur between the valve body 40 and the guide hole (the second guide hole 62 or the third guide hole 72), dimensional changes in the throttle section S are suppressed, and the flow rate of the fluid passing through the throttle section S can be stabilized.

[0051] In this case, the resin material used to mold the inner cylindrical portion 60 and the longitudinal inner cylindrical portion 70 may contain a filler such as PTFE (polytetrafluoroethylene), carbon, or graphite. This further improves the durability of the inner cylindrical portion 60 and the longitudinal inner cylindrical portion 70, thereby improving the durability of the motor-operated valve 1. In this case, a resin surface similar to the resin surface that forms the inner circumferential surface of the guide hole (the inner circumferential surface of the second guide hole 62 or the third guide hole 72) may be provided on the outer circumferential surface of at least the straight portion 41 of the valve body 40. In this case, the portion of the valve body 40 that slides against the inner circumferential surface of the guide hole 55 is made of resin, thereby further improving the slidability of the valve body 40, suppressing the above-mentioned wear, and further improving the durability of the motor-operated valve 1.

[0052] Furthermore, this configuration using a resin surface portion can also be adopted in the flow path member 50 of the first embodiment that does not have the inner tube portion 60 or the long-axis inner tube portion 70, and the entire flow path member 50 may be an integrally molded resin part molded using a resin material such as PPS (polyphenylene sulfide) or PEEK (polyether ether ketone).

[0053] 7 to 9 are diagrams showing variations in the arrangement of the communication holes 54 of the flow path member 50. The flow path member 50 shown in FIG. 7(A) is a flow path member 50 including the inner cylindrical portion 60 described above. In this flow path member 50, the communication holes 54 open in the direction opposite to the direction facing the A port 13. In contrast, the flow path members 50 shown in FIGS. 7(B) and 7(C) have a plurality of communication holes 54 formed therein. Although not shown, it is assumed that the A port 13 shown in FIG. 7(A) is also arranged in the same orientation next to the flow path member 50 shown in FIGS. 7(B), 7(C), and 8. In the flow path member 50 shown in FIG. 7(B), in addition to the communication hole 54 opening in the direction opposite to the direction facing the A port 13, two more communication holes 54 are formed in the orthogonal direction perpendicular to the penetrating direction of the A port 13 in a cross-sectional view perpendicular to the axis L. In the flow path member 50 shown in Figure 7(C), in addition to the communicating hole 54 that opens in the direction opposite to the direction facing the A port 13, two more communicating holes 54 are formed in an intersecting direction that intersects with the penetrating direction of the A port 13 when viewed in a cross section perpendicular to the axis L.

[0054] In the flow path member 50 shown in Fig. 8, instead of forming a communication hole 54 that opens in the direction opposite to the direction facing the A port 13, a total of four communication holes 54 that all open in intersecting directions are formed. In the flow path member 50 shown in Fig. 9, the communication holes 54 are formed at positions that are not included in the diameter range 14a from the upper end to the lower end in the direction of the axis L of the first joint pipe 14 (effectively the diameter range of the A port 13). Specifically, the communication hole 54 opens above the diameter range 14a, facing the inner surface of the side wall 12 on which the A port 13 is formed. In this way, the communication holes 54 shown in Figs. 7 to 9 are provided at non-facing positions that do not face the A port 13. 7 to 9, the non-facing position includes a position facing the opposite direction to the facing direction of the A port 13, a position facing the orthogonal direction and the intersecting direction, a position not included in the bore size range 14a of the first joint pipe 14 (the bore size range of the A port 13), and a combination of these. In addition to these, the non-facing position also includes a position where the communicating hole 54 opens at an angle with respect to the penetration direction of the A port 13 in a cross-sectional view taken along the axis L direction shown in FIG.

[0055] This configuration prevents the fluid that flows into the valve chamber 11 from the A port 13 from proceeding linearly to the communicating hole 54 in the flow direction and colliding with the valve disc 40. That is, the fluid that flows in from the A port 13 first collides with the outer surface of the flow path member 50 to absorb the impact, and then enters the communicating hole 54. This reduces the force applied to the valve disc 40, and suppresses vibration of the valve disc 40. Note that in this configuration in which the communicating hole 54 is provided in a non-opposing position, the fluid that flows into the valve chamber 11 from the A port 13 first collides with the outer peripheral surface of the flow path member 50, causing the fluid flow to become non-unidirectional and disrupted. In particular, when the communicating hole 54 is located opposite the A port 13 as shown in FIG. 7A , the fluid that collides with the outer peripheral surface of the flow path member 50 splits into two flows on the outer peripheral surface of the flow path member 50 and converges at the communicating hole 54, making the fluid flow more disruptive.

[0056] 7(B) to 8, when a plurality of communication holes 54 are provided radially in a cross section perpendicular to the axis L, the distance from the position where the fluid first strikes the outer peripheral surface of the flow path member 50 to each communication hole 54 is different, and therefore the pressure of the fluid entering each communication hole 54 is different for each communication hole 54, causing the flow of the fluid to become turbulent. However, as described above, by making the flow path cross-sectional area of ​​the communication holes 54 uniform and making the length in the penetration direction equal to or greater than the size of the inner diameter, a rectifying effect can be achieved. Therefore, particularly when the flow of the fluid is turbulent, the fluid can be rectified before flowing into the throttle section S, making it possible to further suppress vibration of the valve body 40.

[0057] Next, a first modified example of the first embodiment will be described. FIG. 10 is a cross-sectional view of a flow path member 50′ according to a first modified example of the first embodiment, taken along the axis L. In the first modified example, a guide member 80 is provided that combines the functions of the flow path member 50 and the support member 20 described above. The guide member 80 includes a support member 20′ and a flow path member 50′. That is, the support member 20′ and the flow path member 50′ are integrally provided in the motor-operated valve 1. The support member 20′ of the guide member 80 does not have the mounting recess 25 described above, and the flow path member 50′ is provided continuously with the lower surface of the support member 20′. Furthermore, the second insertion hole 23b of the support member 20′ and the guide hole 55 of the flow path member 50′ are continuously connected without a boundary. Note that the structures of the support member 20′ are substantially the same as those of the support member 20 described above, and the structures of the flow path member 50′ are substantially the same as those of the flow path member 50 described above. Therefore, the same reference numerals are used to designate similar components, and their descriptions are omitted or simplified.

[0058] This configuration can achieve the same effects and advantages as the first embodiment. Furthermore, since the flow path member 50′ and the support member 20′ can be integrally formed, the components of the motor-operated valve 1 can be simplified, and the motor-operated valve 1 can be easily assembled. Furthermore, this configuration prevents the flow path member 50′ and the support member 20′ from being misaligned with each other during manufacturing or use. This ensures that the guide hole 55 of the flow path member 50′ and the insertion hole 23 of the support member 20′ are coaxial. This reduces the sliding resistance between the valve element 40 and the inner circumferential surface of the guide hole 55. This suppresses the above-described wear, improves the durability of the motor-operated valve 1, and suppresses dimensional changes in the throttle section S, stabilizing the flow rate of the fluid passing through the throttle section S.

[0059] Next, a second modified example of the first embodiment will be described. FIG. 11 is a cross-sectional view of a flow path member 50′ according to the second modified example of the first embodiment, taken along the axis L. The second modified example also includes a guide member 80. In the second modified example, a connecting member 27 is provided to surround the outer peripheral surface of the support member 20′, and this connecting member 27 is press-fitted into the upper end opening of the valve body 10. The opening edge of the case 19 is fixed to the flange portion 24 of the support member 20′ by welding or the like, rather than to the upper end of the side wall 12 of the valve body 10. The second insertion hole 23b of the support member 20′ has an inner diameter larger than that of the guide hole 55 of the flow path member 50′. The outer diameter of the extension portion 52 of the flow path member 50′ is set larger than that of the connection portion 51. The lower end (tip) of the connection portion 51 does not abut against the upper end surface of the second joint pipe 18 when inserted and fixed in the B port 17. As a result, a space B is formed between the connecting portion 51 and the upper end surface of the second joint pipe 18.

[0060] As described above, the second joint pipe 18 is inserted into the B port 17 and fixed by brazing or the like. At this time, a fillet of brazing material is formed at a corner 18a (shown only in FIG. 11 ) formed by the inner circumferential surface of the B port 17 and the end face of the second joint pipe 18. The fillet portion gets in the way, making it difficult to install the connection portion 51 of the flow path member 50 in the B port 17, or the connection portion 51 may be fixed at an unintended angle. However, according to the present configuration, the space B is formed between the tip of the connection portion 51 of the flow path member 50 and the upper end face of the second joint pipe 18, so the fillet can be contained within the space, and the flow path member 50 can be stably fixed in the valve chest 11 without being affected by the fillet.

[0061] Next, a second embodiment of the present invention will be described. Fig. 12 is a cross-sectional view of a motor-operated valve 100 according to the second embodiment, taken along the axis L. The motor-operated valve 100 includes a valve body 110, a support member 120, a drive unit 130, a valve element 140, and a flow path member 150. The valve body 110 is formed in a generally cylindrical box shape using a metal material such as brass or stainless steel, and includes a valve chamber 111 therein. An A port 112 is formed in the side wall (side surface) of the valve body 110, penetrating radially therethrough. The A port 112 is formed in a stepped shape with a small-diameter portion on the valve chamber 111 side and a large-diameter portion continuing from the small-diameter portion. A first coupling pipe 113, which serves as a piping for a refrigerant (fluid), is inserted into the large-diameter portion. The first coupling pipe 113 is fixed to the valve body 110 by brazing or the like, and its interior is in communication with the valve chamber 111.

[0062] A B port 114 is formed in the center of the bottom wall of the valve body 110, penetrating the valve body 110 in the direction of the axis L. The B port 114 is formed in a stepped shape with a small-diameter portion on the valve chamber 111 side and a large-diameter portion continuous with the small-diameter portion, and a second coupling pipe 115, which serves as a refrigerant pipe, is inserted into the large-diameter portion. The second coupling pipe 115 is fixed to the valve body 110 by brazing or the like, and its interior is in communication with the valve chamber 111. An opening penetrating the center of the top wall of the valve body 110 in the direction of the axis L is formed at the edge of the opening, and a cylindrical mounting portion 116 rising upward is formed at the edge of the opening. A lid 117 is attached to the upper surface of the top wall of the valve body 110, surrounding the mounting portion 116 in the circumferential direction. A cylindrical case 118 with a bottom is hermetically fixed to the upper surface of the lid 117 by welding or the like at the edge of its opening.

[0063] The support member 120 is a member that supports a drive shaft 132 (described later) within the valve chamber 111 and is made of a resin material. The support member 120 includes a cylindrical press-fit portion 121, a flange portion 122 that protrudes radially outward from above the press-fit portion 121, a fixed-side stopper 123 formed on a portion of the outer edge of the flange portion 122, and a holder portion 124 that extends upward from the center of the flange portion 122 in the direction of the axis L. The press-fit portion 121 is press-fitted into the mounting portion 116 of the valve body 110. The flange portion 122 is supported by the mounting portion 116, with its lower end surface abutting against the upper end surface of the mounting portion 116. The fixed-side stopper 123 is formed by rising upward from a portion of the outer edge of the flange portion 122, and its surface facing the circumferential direction about the axis L is able to abut against a movable-side stopper 136 of the magnet rotor 131 (described later). A male thread portion 125 that screws into a female thread portion 135 (described later) is formed on the outer peripheral surface of the holder portion 124. An insertion hole 126 that penetrates from the upper end to the lower end in the direction of the axis L is formed in the center of the support member 120. The insertion hole 126 is a hole through which the drive shaft 132 is inserted, penetrates from the upper end to the lower end of the support member 120 in the direction of the axis L, and communicates with the valve chamber 111.

[0064] The drive unit 130 is composed of a stepping motor. The drive unit 130 is composed of a magnet rotor 131 disposed within the case 118, a stator coil (not shown) disposed outside the case 118 and surrounding the magnet rotor 131 in the circumferential direction, a drive shaft 132 attached to the center of the magnet rotor 131, and other components (not shown), such as a yoke and exterior members. The magnet rotor 131 is formed into a cylindrical shape with a main body forming the center and a magnet fixed to the outer periphery of the main body. The center of the magnet rotor 131 is formed with a mounting hole 133 penetrating in the direction of the axis L and a slide hole 134 communicating with the mounting hole 133 and opening downward. An upper portion 137 of the drive shaft 132 is inserted into the mounting hole 133. A female thread portion 135 that threads onto the male thread portion 125 of the support member 120 is formed on the inner circumferential surface of the slide hole 134. The magnet rotor 131 is supported by the support member 120 in the valve chamber 111 by the female thread portion 135 being screwed into it.

[0065] A movable-side stopper 136 that protrudes downward is formed on a portion of the lower end surface of the magnet rotor 131. The movable-side stopper 136 is formed to protrude downward from a portion of the lower surface of the magnet rotor 131, and the surface facing the circumferential direction about the axis L is able to abut against the fixed-side stopper 123 of the support member 120. The drive shaft 132 is formed to extend in the direction of the axis L and includes a small-diameter upper portion 137 that is inserted into the mounting hole 133, and a large-diameter lower portion 138 that is continuous with the upper portion 137. The upper end portion of the upper portion 137 protrudes above the magnet rotor 131 and is press-fitted into an annular fixing member 139, and the magnet rotor 131 and the drive shaft 132 are integrated by fixing the fixing member 139 to the magnet rotor 131 by welding or the like. The lower portion 138 is inserted into the insertion hole 126 of the support member 120 and is guided by the insertion hole 126 so as to be movable in the direction of the axis L.

[0066] In the second embodiment, when the magnet rotor 131 rotates around the axis L, the female thread portion 135 is threaded, thereby moving the magnet rotor 131 and the drive shaft 132 in the direction of the axis L. That is, the male thread portion 125 provided on one of the support member 120 and the drive unit 130 and the female thread portion 135 provided on the other constitute a screw feed mechanism A. In this embodiment, the rotation of the magnet rotor 131 is restricted by contact between the fixed-side stopper 123 and the movable-side stopper 136. A compressed first spring 160 is disposed between the magnet rotor 131 and the ceiling surface of the case 118. A compressed second spring 161 is disposed within the slide hole 134 of the magnet rotor 131, between the lower surface of the magnet rotor 131 and the upper surface of the lower portion 138. As a result, the magnet rotor 131 and the drive shaft 132 are biased toward the B port 114.

[0067] The valve element 140 is continuous with the lower end of the drive shaft 132, extends along the axis L, and is rotatable around the axis L and movable in the direction of the axis L inside the flow path member 150. The valve element 140 includes a straight portion 141 that is continuous with the lower end of the drive shaft 132, a needle portion 142 that is continuous with the lower end (tip) of the straight portion 141, and a connecting portion 143 that forms the boundary between the straight portion 141 and the needle portion 142. The structure of the valve element 140 is similar to that of the valve element 40 of the first embodiment described above, and therefore a detailed description thereof will be omitted here.

[0068] The flow path member 150 includes a connection portion 151 that communicates with the B port 114 and is fixed to the valve body 110, an extension portion 152 that is continuous with the connection portion 151 and extends upward along the axis L, and a through hole 153 that passes through the centers of the connection portion 151 and the extension portion 152 in the direction of the axis L. The connection portion 151 is formed in a flange shape that protrudes radially outward from the lower end of the extension portion 152, and is fixed to the valve body 110 by being sandwiched in the direction of the axis L between the open end edge of the small diameter portion of the B port 114 and the upper end face of the second joint pipe 115 inserted into the B port 114. The extension portion 152 is formed in a cylindrical shape, and its upper end portion is press-fitted into the lower end side of the insertion hole 126 of the support member 120 and fixed to the support member 120.

[0069] A communicating hole 154 is formed in the side surface of the extension portion 152, penetrating radially. In contrast, the through hole 153 penetrates in the direction of the axis L, with an upper end portion communicating with the insertion hole 126 of the support member 120 and a lower end portion communicating with the interior of the second joint pipe 115 via the B port 114. The upper portion of the through hole 153 forms a guide hole 155, and the lower portion of the through hole 153 forms a connecting hole 156. In the second embodiment as well, a throttle section S, the opening size of which is variable, is formed between the outer peripheral surface of the valve element 140 and the inner peripheral surface of the guide hole 155, and the fluid that flows into the valve chamber 111 from the A port 112 passes through the communicating hole 154 and the throttle section S before flowing to the B port 114.

[0070] According to this embodiment, the same functions and effects as those of the first embodiment and the modified example can be achieved even in a drive-type motor-operated valve 100 in which the magnet rotor 131 is provided with the female thread portion 135. Furthermore, according to this embodiment, the connection portion 151 of the flow path member 150 is formed in a flange shape and is fixed by being sandwiched in the direction of the axis L between the open end edge of the small diameter portion of the B port 114 and the upper end face of the second joint pipe 115 inserted into the B port 114. This makes it possible to maintain the connected state of the flow path member 150 more stably, thereby further suppressing vibration of the valve element 140.

[0071] In the second embodiment, the upper portion of the through hole 153 is the guide hole 155, and the lower portion is the connecting hole 156. However, the connecting hole 156 may be omitted. This is the same as in the first embodiment and the various modifications described above. For example, in the flow path member 50 of the motor-operated valve 1 shown in FIG. 1 , the guide hole 55 may be extended to the lower end of the flow path member 50, and the entire portion from the upper end communicating with the second insertion hole 23b to the lower end communicating with the B port 17 may be the guide hole 55 (in this case, the entire portion other than the portion inserted into the B port 17 becomes the extended portion 52). In other words, the through hole 153 does not necessarily have to be composed of the guide hole 155 with a small inner diameter and the connecting hole 156 with a large inner diameter, and may be composed of only the guide hole 155 with a constant inner diameter. Conversely, the through hole 153 may be formed in a multi-step shape so that the inner diameters vary in the direction of the axis L. However, in this case, in order to ensure that the area between the outer peripheral surface of the valve body 140 and the inner peripheral surface of the guide hole 155 forms the throttle section S, the inner diameter dimension of the portion that becomes the guide hole 155 is made the smallest. [Explanation of symbols]

[0072] L axis S Constriction section 1. Motor-operated valve 10 Valve body 11 Valve chamber 12 Side wall (side) 17 B port 40 Valve body 41 Straight section 42 Needle part 43 Connecting part (boundary part) 50 Flow path member 51 Connection 52 Extension 54 Communication hole 55 Guide hole

Claims

1. An electrically operated valve comprising: a valve body having a valve chamber therein and a B port opened to a bottom surface of the valve chamber; a flow path member fixed within the valve chamber; and a valve disc provided within the flow path member so as to be movable in an axial direction, the flow path member comprises: a connection portion communicating with the B port and fixed to the valve body; an extension portion continuing from the connection portion and extending in a direction opposite to the B port; a guide hole penetrating the extension portion in the axial direction and having a constant diameter; and a communication hole penetrating a side surface of the extension portion and communicating between the valve chamber and the guide hole, the valve body includes a straight portion that is inserted into the guide hole and has a constant diameter, a needle portion that is continuous with a tip side of the straight portion and has a tapered diameter, and a boundary portion that is a boundary between the straight portion and the needle portion, An electric valve characterized in that a throttling portion is formed between the outer peripheral surface of the valve body and the inner peripheral surface of the guide hole, and the opening size of the throttling portion can be changed by moving the valve body in the axial direction with the boundary portion overlapping the communicating hole.

2. 2. The motor-operated valve according to claim 1, wherein a resin surface portion made of resin is provided on an inner peripheral surface of the guide hole in a range spanning at least the communication hole in the axial direction.

3. 3. The motor-operated valve according to claim 2, wherein the flow passage member is an integrally molded part made of resin.

4. 2. The motor-operated valve according to claim 1, wherein a resin surface portion made of resin is provided on an outer peripheral surface of at least the straight portion of the valve body.

5. a drive unit having a drive shaft connected to the valve body; and a support member fixed to the valve body and having an insertion hole through which the drive shaft is inserted, a male thread portion provided on one of the drive portion and the support member and a female thread portion provided on the other of the drive portion and the support member constitute a screw feed mechanism; The motor-operated valve according to any one of claims 1 to 4, characterized in that the guide hole and the insertion hole are coaxially continuous, and the flow path member is fixed to the support member.

6. 6. The motor-operated valve according to claim 5, wherein the support member and the flow path member are integrally formed.

7. 5. The motor-operated valve according to claim 1, wherein the connecting portion of the flow path member is formed in a cylindrical shape and is inserted and fixed into the B port.

8. 8. The motor-operated valve according to claim 7, wherein a space is formed between the tip of the connection portion of the flow path member and an end face of a pipe connected to the B port.

9. the valve body includes an A port that opens to a side surface of the valve chamber, The fluid that flows into the valve chamber from the A port passes through the communication hole and the throttle portion, and then flows to the B port.

5. The motor-operated valve according to claim 1, wherein the communication hole is provided at a non-opposing position that does not face the A port.

10. 10. The motor-operated valve according to claim 9, wherein the communication hole is formed in a circular shape when viewed from the penetration direction, has a uniform flow path cross-sectional area, which is the opening area when cut in a direction perpendicular to the flow direction of the fluid flowing inside, and the length from the opening on the valve chamber side to the opening on the guide hole side is equal to or greater than the size of the inner diameter.

11. 10. A refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the motor-operated valve according to claim 1 is used as the expansion valve.

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