Electric valves and refrigeration circulation system

Abstract

This invention provides an electric valve and a refrigeration circulation system that can both ensure the operability of valve components and suppress valve leakage. A valve core (2) is slidably inserted into a valve core support (6) in a state of suspension from a fitting mounting hole (62a) at the end of a valve core support (6) located on the valve port (14) side. A cylindrical valve guide member (1B) with its shaft (22) fixed to the valve body (1) guides the valve core in the direction of axis L. Furthermore, when the gap between the valve core (2) and the valve guide member (1B) is set to A, the gap between the valve core support (6) and the support guide member (5d) is set to B, and the gap between the valve core (2) and the fitting mounting hole (62a) of the valve core support (6) is set to C, the relationship between these gaps A and C is set to A < B and A < C.

Description

Technical Field

[0001] This invention relates to electric valves for use in refrigeration circulation systems and the like, as well as refrigeration circulation systems. Background Technology

[0002] As an electric valve, there is a known electric valve that includes the following components: a valve body having a valve chamber and a valve port; a valve core for changing the opening degree of the valve port; a drive unit for driving the valve core forward and backward in the axial direction; and a support member that, together with the drive shaft of the drive unit, constitutes a threaded feed mechanism (for example, see Patent Document 1). In the electric valve of Patent Document 1, the rotational motion of the drive shaft of the drive unit is converted into linear motion in the axial direction of the drive shaft by the threaded feed mechanism, and the valve port opening degree is controlled by the valve component of the valve core connected to the drive shaft.

[0003] Here, regarding this electric valve, an assembly cross-sectional view showing the fully closed state of a conventional electric valve is used. Figure 4 To explain in detail, for example, such as... Figure 4 As shown, the valve body 1 includes: a cylindrical valve housing component 1A; a valve guide component 1B fixed inside the valve housing component 1A; a cylindrical outer shell 4 fixed to the upper part of the valve housing component 1A; and a support component 5 fixed to the upper opening of the outer shell 4. Furthermore, the concept of "upper and lower" in this description is different from... Figure 4 The top and bottom correspondences in the text.

[0004] The valve housing component 1A has a generally cylindrical valve chamber 1C formed inside, and a first connector pipe 11 communicating with the valve chamber 1C is installed from the side. Furthermore, a cylindrical valve port 14 serving as a valve orifice is formed at the center of the valve seat portion 13 in the valve housing component 1A. An edge 1b is formed at the upper end of the valve housing component 1A to surround the valve guide component 1B. A cylindrical portion 15, containing a portion of the valve port 14, is formed on the bottom surface of the valve housing component 1A. A second connector pipe 12 communicating with the valve chamber 1C is disposed on the outer periphery of the cylindrical portion 15 and is brazed to the bottom of the valve housing component 1A. When refrigerant flows in from the first connector pipe 11, the refrigerant flows out through the valve chamber 1C from the second connector pipe 12. Conversely, when refrigerant flows in from the second connector pipe 12, the refrigerant that has passed through the valve port 14 and the valve chamber 1C flows out from the first connector pipe 11. In addition, the cylindrical inner circumferential surface of the cylindrical portion 15 is continuously formed with the valve port 14 of the valve housing component 1A, and is integrally formed with the valve housing component 1A.

[0005] The valve guide component 1B, serving as the valve guide, is pressed into the upper part of the valve housing component 1A and installed in a state where it is inserted into the valve chamber 1C. A valve guide hole 16 is formed in the valve guide component 1B with the axis L as the center. The outer shell 4 is assembled in such a way that it fits into the outer periphery of the edge 1b of the valve housing component 1A. The edge 1b is riveted and the bottom outer periphery is brazed, thereby fixing it to the valve housing component 1A.

[0006] The support member 5 is welded and fixed to the upper opening of the housing 4 via the fixing fitting 41. An internal thread portion 5a is provided at the center of the upper side of the support member 5, which is coaxial with the axis L of the valve port 14, etc., and a cylindrical guide hole 5c with a diameter larger than the outer periphery of the internal thread portion 5a is formed on the lower side.

[0007] The valve core 2, as a valve component, includes: a shaft 22 as a shaft portion, which has a needle portion 21 at its lower front end; and a valve core support 6 that holds the upper end of the shaft 22. A flange portion 23 is formed at the upper end of the shaft 22. Furthermore, the needle portion 21, located on the shaft 22, is situated within the valve port 14 when the valve core 2 is in its lowest fully closed state, and has a shape with a percentage-based chamfering effect, where the diameter decreases towards its front end. In this case, the needle portion 21 connects to the seat portion 21a of the valve seat portion 13 when the valve core 2 is in its lowest fully closed state. Alternatively, the valve core 2 can be configured such that even when in its lowest fully closed state (i.e., when closest to the valve seat portion 13), the needle portion 21 does not contact the valve seat portion 13, thereby achieving a small opening.

[0008] The valve core support 6 has a flange 23 of the rod shaft 22 fixed to its lower end in a cylindrical portion 61, and a spring seat 63, a compression coil spring 64, and a washer 65 are provided inside the cylindrical portion 61. That is, the valve core support 6 has a valve core 2 fixed at one end on the valve port 14 side by press-fitting and welding, and houses a compression coil spring 64 that applies force to the valve core 2 and the spring seat 63 in a separation direction. Furthermore, a rotor shaft 32, which serves as a drive shaft and will be described later, is connected to the other end of the valve core support 6. At least one of the valve core 2 and the rotor shaft 32 is connected to the valve core support 6 in an anti-detachment state and is capable of moving back and forth inside the valve core support 6. The valve core support 6 is inserted through the guide hole 5c of the support member 5 and is supported so that it can slide along the axis L. That is, the lower side of the guide hole 5c of the support member 5 functions as a support guide 5d for guiding the valve core support 6.

[0009] The stepper motor 3, which serves as the drive unit, includes: a housing 7, a magnetic rotor 31 disposed within the housing 7, a rotor shaft 32, a stator coil (not shown), and a rotation limit mechanism 8 for the stepper motor 3.

[0010] The housing 7 is airtightly fixed to the upper end of the outer casing 4 by welding or other means, and houses the support component 5 and the magnetic rotor 31. The outer periphery of the magnetic rotor 31 is magnetized into multiple poles, and a rotor shaft 32 is fixed at its center. The lower end of the rotor shaft 32 passes through the upper end of the cylindrical portion 61 of the valve core support 6, abuts against the upper surface of the spring seat 63, and the anti-detachment flange portion 32c is held inside the cylindrical portion 61 by a washer 65. In addition, an external thread portion 32a is formed on the upper side surface of the middle portion of the rotor shaft 32. This external thread portion 32a is threadedly engaged with the internal thread portion 5a of the support component 5, and these external thread portions 32a and internal thread portions 5a constitute the threaded feed mechanism 17 of the drive unit. The threaded feed mechanism 17 converts the rotational motion of the stepper motor 3 into the linear motion of the rotor shaft 32, thereby driving the valve core 2 forward and backward in the direction of the axis L. The stator coil is disposed on the outer periphery of the housing 7. By applying a pulse signal to the stator coil, the magnetic rotor 31 rotates according to the number of pulses, thereby rotating the rotor shaft 32.

[0011] The rotation limiting mechanism 8 of the stepper motor 3 has a guide support 8A fixed to the top of the housing 7. The guide support 8A includes: a cylindrical guide 86 that hangs down from the center of the top of the housing 7 along the axis; a helical guide 87 fixed to the outer periphery of the guide 86; and a movable slider 88 that is guided by the helical guide 87 and can rotate and move up and down. The movable slider 88 is provided with a claw portion 88a that protrudes radially outward, and the magnetic rotor 31 is provided with an extension portion 31a that extends upward and abuts against the claw portion 88a. When the magnetic rotor 31 rotates, the extension portion 31a presses against the claw portion 88a, thereby causing the movable slider 88 to rotate and move up and down in accordance with the helical guide 87. In addition, a cylindrical component 8B that guides the upper part of the rotor shaft 32 is fitted inside the cylindrical guide 86.

[0012] The spiral guide 87 has an upper limit member 87a that defines the uppermost position of the magnetic rotor 31 and a lower limit member 87b that defines the lowermost position of the magnetic rotor 31. When the movable slider 88, which descends as the magnetic rotor 31 rotates in the forward direction, comes into contact with the lower limit member 87b, the movable slider 88 cannot rotate at that contact position, thereby restricting the rotation of the magnetic rotor 31 and stopping the descent of the valve core 2. On the other hand, when the movable slider 88, which rises as the magnetic rotor 31 rotates in the reverse direction, comes into contact with the upper limit member 87a, the movable slider 88 cannot rotate at that contact position, thereby restricting the rotation of the magnetic rotor 31 and stopping the rise of the valve core 2.

[0013] Existing technical documents

[0014] Patent documents

[0015] Patent Document 1: Japanese Patent Application Publication No. 2021-124153 Summary of the Invention

[0016] The problem that the invention aims to solve

[0017] However, electric valves used in refrigeration and air conditioning systems, besides controlling the amount of fluid flowing inside the valve, sometimes also need to impede flow. However, when the valve core moves up and down, the pressure difference and dynamic pressure within the valve chamber caused by the fluid flowing through the valve can cause the valve core to tilt and sit at an angle. Therefore, it is important to ensure the valve core sits accurately on the valve seat. One improvement to address this problem is to extend the valve guide hole of the valve guide component to guide the valve core closer to the valve seat. However, if the coaxiality of the support guide, valve core guide, and valve seat is low, the valve core may be constrained (causing locking). Therefore, it is necessary to improve assembly precision.

[0018] Especially when the valve core and valve core support are integrated, the valve core and valve core support cannot move relative to each other in the radial direction. Therefore, the coaxiality of the support guide, valve core guide, and valve seat is particularly affected. Consequently, it is necessary to increase the clearance between the valve core guide and the valve core, which can easily lead to valve leakage.

[0019] Therefore, the object of the present invention is to provide an electric valve and a refrigeration circulation system that can both ensure the operation of valve components and suppress valve leakage.

[0020] Solution for solving the problem

[0021] The electric valve of the present invention comprises: a valve body having a valve chamber and a valve port; a valve component that changes the opening degree of the valve port; a drive unit having a drive shaft that drives the valve component forward and backward in the axial direction of the valve port; a support member that, together with the drive shaft, forms a threaded feed mechanism; a valve bracket extending over the valve component and the drive shaft; and a bracket guide that guides the valve bracket in the axial direction. The threaded feed mechanism converts the rotational motion of the drive unit into linear motion in the axial direction of the drive shaft. The valve component connected to the drive shaft controls the opening degree of the valve port. The feature is that the aforementioned support member is fixed to the aforementioned valve body, the aforementioned valve component and the aforementioned drive shaft are concentrically arranged, the aforementioned valve component is slidably inserted into the aforementioned valve bracket in a state of being suspended from the fitting mounting hole provided at the end of the aforementioned valve port side of the aforementioned valve bracket, and is guided in the aforementioned axial direction by the cylindrical valve guide portion fixed to the aforementioned valve body. When the gap between the aforementioned valve component and the aforementioned valve guide portion is set as A, the gap between the aforementioned valve bracket and the aforementioned bracket guide is set as B, and the gap between the aforementioned valve component and the aforementioned fitting mounting hole of the aforementioned valve bracket is set as C, the relationship between these gaps A to C is set as A < B, A < C.

[0022] According to this invention, the valve component can be driven effectively, suppressing dimensional deviations in the drive section (the external thread of the drive shaft, the internal thread of the support member, and the joint between the drive shaft and the valve support) and the effects of wobbling during operation. That is, even when the drive section (the external thread of the drive shaft, the internal thread of the support member, and the joint between the drive shaft and the valve support) is misaligned, the amount of movement of the valve component is limited by the gap between the valve component and the valve guide, thus ensuring concentricity with the valve seat. In this way, both the operability of the valve component and valve leakage can be ensured.

[0023] In this case, it is preferable that the relationship between the aforementioned gap B and the aforementioned gap C is set such that B < C. Therefore, the radial movement of the valve support is limited before the valve component contacts the fitting mounting hole, and thus the valve component is not affected by radial misalignment of the valve support. That is, the fitting mounting hole and the valve component do not contact each other and do not become sliding resistance.

[0024] Furthermore, preferably, the valve component has a shaft portion guided by the valve guide portion, and the amount by which the valve component is guided by the valve guide portion in the axial direction is set to be longer than the diameter of the shaft portion of the valve component. Thus, the valve component is guided with sufficient length, thereby reducing valve leakage.

[0025] The refrigeration cycle system of the present invention includes a compressor, a condenser, an expansion valve, and an evaporator, characterized in that any one of the above-mentioned electric valves is used as the expansion valve.

[0026] According to this invention, as described above, the electric valve of the present invention drives the valve components in a way that suppresses the effects of swaying during drive, thereby ensuring both the operability of the valve components and suppressing valve leakage, thus enabling a refrigeration cycle system that is energy-efficient and less prone to adverse conditions during operation.

[0027] Invention Effects

[0028] The electric valve and refrigeration circulation system according to the present invention can both ensure the operability of valve components and suppress valve leakage. Attached Figure Description

[0029] Figure 1 This is a longitudinal sectional view showing an embodiment of the electric valve of the present invention.

[0030] Figure 2 It is an enlarged representation Figure 1 A longitudinal sectional view of the main parts of the electric valve.

[0031] Figure 3 This is a diagram illustrating an example of the refrigeration cycle system of the present invention.

[0032] Figure 4 This is a longitudinal sectional view showing an existing electric valve.

[0033] In the picture:

[0034] 1—Valve body, 1A—Valve housing component, 1B—Valve guide component, 1C—Valve chamber, 2—Valve core (valve component), 21—Needle part, 21a—Seating surface, 22—Rod shaft, 3—Stepper motor (drive part), 32—Rotor shaft (drive shaft), 32a—External thread part, 5—Support component, 5a—Internal thread part, 5d—Bracket guide part, 6—Valve core bracket (valve bracket), 62a—Matching mounting hole, 10—Electric valve, 13—Valve seat part, 131—Seating part, 14—Valve port, 17—Threaded feed mechanism, 100—Expansion valve, 200—Outdoor heat exchanger (condenser, evaporator), 300—Indoor heat exchanger (condenser, evaporator), 400—Flow path switching valve, 500—Compressor. Detailed Implementation

[0035] Reference Figure 1 and Figure 2 The electric valve according to embodiments of the present invention will be described in detail. Figure 1 As shown, the electric valve 10 of this embodiment includes a valve body 1, a valve core 2 as a valve component, a stepper motor 3 as a drive unit, and a valve port 14. Furthermore, the concept of "up and down" in the following description is different from... Figure 1 The top and bottom correspondences in the text.

[0036] The valve body 1 has: a cylindrical valve housing component 1A; a valve guide component 1B, which serves as a valve guide and is fixed inside the valve housing component 1A; a cylindrical outer shell 4, which is fixed to the upper part of the valve housing component 1A; and a support component 5, which is fixed to the upper opening of the outer shell 4.

[0037] The valve housing component 1A has a generally cylindrical valve chamber 1C formed inside it, and a first connector pipe 11 communicating with the valve chamber 1C is installed from the side. Furthermore, a cylindrical valve port 14 serving as a valve orifice is formed in the center of the valve seat portion 13 in the valve housing component 1A. An edge 1b is formed at the upper end of the valve housing component 1A to surround the valve guide component 1B. A cylindrical portion 15, containing a portion of the valve port 14, is formed on the bottom surface of the valve housing component 1A. A second connector pipe 12, communicating with the valve chamber 1C, is coaxially disposed on the outer periphery of the cylindrical portion 15 with the valve port 14 and is brazed to the bottom of the valve housing component 1A. When refrigerant flows in from the first connector pipe 11, the refrigerant flows out from the second connector pipe 12 via the valve chamber 1C. Conversely, when refrigerant flows in from the second connector pipe 12, the refrigerant that has passed through the valve port 14 and the valve chamber 1C flows out from the first connector pipe 11. In addition, the cylindrical inner circumferential surface of the cylindrical portion 15 is continuously formed with the valve port 14 of the valve housing component 1A, and is integrally formed with the valve housing component 1A.

[0038] Valve guide component 1B is pressed in from the upper part of valve housing component 1A and installed in a state of insertion into valve chamber 1C. Valve guide hole 16 is formed in valve guide component 1B with axis L as the center. Housing 4 is assembled in such a way that it fits into the outer periphery of edge 1b of valve housing component 1A. Edge 1b is riveted and the bottom outer periphery is brazed, thereby fixing it to valve housing component 1A.

[0039] The support member 5 is welded and fixed to the upper opening of the housing 4 via the fixing fitting 41. An internal thread portion 5a, coaxial with the axis L of the valve port 14, is provided at the center of the upper side of the support member 5, and a cylindrical guide hole 5c, with a diameter larger than the outer periphery of the internal thread portion 5a, is formed on the lower side. In this embodiment, the support member 5 is fitted into the upper opening of the housing 4 via the fixing fitting 41 in a welded fixed state, but the support member 5 can also be pressed into the housing 4.

[0040] The valve core 2 includes: a shaft 22 serving as a shaft portion, which has a needle portion 21 at its lower front end; and a valve core support 6 that holds the upper end of the shaft 22. The shaft 22 is slidably inserted into the valve guide hole 16 of the valve guide member 1B in the direction of axis L. Furthermore, a flange portion 23 is formed at the upper end of the shaft 22. In addition, when the valve core 2 is moved to the lowermost fully closed state, the needle portion 21 of the shaft 22 is connected to the seat portion 21a of the needle portion 21 seated on the valve seat portion 13, and has a shape with equal percentage characteristics, which is chamfered in multiple layers as it narrows towards its front end. In addition, the valve core 2 can also be configured such that even when it is moved to the lowermost fully closed state (i.e., the state closest to the valve seat portion 13), the needle portion 21 does not contact the valve seat portion 13, thereby obtaining a small opening. Furthermore, the needle portion 21 is not limited to equal percentage characteristics, but can also be a chamfered shape that can obtain the usual linear characteristics or linear characteristics that vary in multiple stages.

[0041] The valve core support 6 has a boss 62 fixed to the lower end of the cylindrical portion 61, and a spring seat 63, a compression coil spring 64, a washer 65, and a gasket portion 67 are provided inside the cylindrical portion 61. Furthermore, the upper end of a rod shaft 22 is inserted into the fitting hole 62a of the boss 62, and the flange portion 23 of the rod shaft 22 abuts against the boss 62, thereby holding the upper end of the rod shaft 22 in place. The valve core support 6 is inserted into the guide hole 5c of the support member 5 and is supported so that it can slide along the axis L. That is, the valve core 2 is suspended at one end of the valve core support 6 on the valve port 14 side, and a compression coil spring 64 is accommodated to exert force on the valve core 2 and the spring seat 63 in a separating direction. In addition, a rotor shaft 32, which serves as a drive shaft and will be described later, is connected to the other end of the valve core support 6. At least one of the valve core 2 and the rotor shaft 32 is connected relative to the valve core support 6 in a non-detachable state and is capable of moving forward and backward within the valve core support 6.

[0042] In this embodiment, the thickness of the flange portion 32c of the rotor shaft 32 is thinner than the height of the recess 67a formed in the gasket portion 67 that accommodates the flange portion 32c. The gasket portion 67 is disposed between the washer 65 and the spring seat 63 within the valve core support 6. That is, the flange portion 32c is spaced apart when it is accommodated in the recess 67a of the gasket portion 67. Therefore, in the open valve state, the force of the compression coil spring 64 is not transmitted to the rotor shaft 32, but the valve core support 6 is suspended from the rotor shaft 32. Moreover, it is configured such that in the closed valve state, the force of the compression coil spring 64 is applied to the rotor shaft 32 for the first time via the spring seat 63. As a result, the valve core support 6 is less susceptible to the influence of wobbling between the rotor shaft 32 and the support member 5. Furthermore, the valve core 2 is guided by the valve guide member 1B, so the valve core 2 can easily sit on the valve seat portion 13 without tilting. That is, after the valve core 2 is seated in the valve seat portion 13, the rotor shaft 32 moves the space between the recess 67a of the gasket portion 67 and the flange portion 32c by an amount, and the aforementioned force begins to act. This reduces valve leakage. Alternatively, the gasket portion 67 and the spring seat 63 can be integrally formed. This reduces the number of parts. Furthermore, the valve core support 6 and the rotor shaft 32 can also be integrally fixed by riveting or the like.

[0043] Furthermore, the valve core bracket 6 is inserted into the guide hole 5c of the support member 5 and guided along the axis L. That is, the lower side of the guide hole 5c of the support member 5 functions as a bracket guide 5d for guiding the valve core bracket 6. Alternatively, the bracket guide 5d can be integrally provided with the support member 5 or separately provided with the support member 5.

[0044] The stepper motor 3, which serves as the drive unit, includes: a housing 7, a magnetic rotor 31 disposed within the housing 7, a rotor shaft 32 serving as the drive shaft, a stator coil (not shown), and a rotation limit mechanism 8 for the stepper motor 3.

[0045] The housing 7 is airtightly fixed to the upper end of the outer casing 4 by welding or other means, and houses the support member 5 and the magnetic rotor 31. The outer periphery of the magnetic rotor 31 is magnetized into multiple poles, and a rotor shaft 32 is fixed at its center. The lower end of the rotor shaft 32 passes through the upper end of the cylindrical portion 61 of the valve core support 6, abuts against the upper surface of the spring seat 63, and the anti-detachment flange portion 32c is held inside the cylindrical portion 61 by a washer 65. In addition, an external thread portion 32a is formed on the upper side surface of the middle portion of the rotor shaft 32. This external thread portion 32a is threadedly engaged with the internal thread portion 5a of the support member 5, and these external thread portions 32a and internal thread portions 5a constitute the threaded feed mechanism 17 of the drive unit. The threaded feed mechanism 17 converts the rotational motion of the stepper motor 3 into the linear motion of the rotor shaft 32, thereby driving the valve core 2 forward and backward in the direction of the axis L. The stator coil is disposed on the outer periphery of the housing 7. By applying a pulse signal to the stator coil, the magnetic rotor 31 rotates according to the number of pulses, causing the rotor shaft 32 to rotate.

[0046] The guide support 8A of the rotation limiting mechanism 8 of the stepper motor 3 is fixed to the top of the housing 7. The guide support 8A includes: a cylindrical guide 86 that hangs down from the center of the top of the housing 7 along the axis; a helical guide 87 fixed to the outer periphery of the guide 86; and a movable slider 88 that is guided by the helical guide 87 and can rotate and move up and down. The movable slider 88 is provided with a claw portion 88a that protrudes radially outward, and the magnetic rotor 31 is provided with an extension portion 31a that extends upward and abuts against the claw portion 88a. When the magnetic rotor 31 rotates, the extension portion 31a presses against the claw portion 88a, thereby causing the movable slider 88 to rotate and move up and down in accordance with the helical guide 87. In addition, a cylindrical component 8B that guides the upper part of the rotor shaft 32 is fitted inside the cylindrical guide 86.

[0047] The spiral guide 87 has an upper limit member 87a that defines the uppermost position of the magnetic rotor 31 and a lower limit member 87b that defines the lowermost position of the magnetic rotor 31. When the movable slider 88, which descends as the magnetic rotor 31 rotates in the forward direction, comes into contact with the lower limit member 87b, the movable slider 88 cannot rotate at that contact position, thereby restricting the rotation of the magnetic rotor 31 and stopping the descent of the valve core 2. On the other hand, when the movable slider 88, which rises as the magnetic rotor 31 rotates in the reverse direction, comes into contact with the upper limit member 87a, the movable slider 88 cannot rotate at that contact position, thereby restricting the rotation of the magnetic rotor 31 and stopping the rise of the valve core 2.

[0048] Furthermore, the structure of the stepper motor 3, which serves as the drive unit in the electric valve 10, is not limited to the shape of having an extension 31a that abuts against the claw portion 88a of the aforementioned movable slider 88. For example, it can also be configured as a coil-shaped driven slider with a claw portion threaded into the guide groove of the support member, as in the electric valve of Patent Document 1.

[0049] In this embodiment, such as Figure 2 As shown, the valve core 2 is slidably inserted into the valve core support 6 in a state of suspension from the fitting mounting hole 62a at the end of the valve core support 6 located on the valve port 14 side, and is configured such that the rod shaft 22 is fixed to the cylindrical valve guide member 1B of the valve body 1 and guided in the direction of the axis L. In addition, the end of the rotor shaft 32 on the stepper motor 3 side is slidably inserted into the valve core support 6.

[0050] Furthermore, when the gap between the valve core 2 and the valve guide member 1B is set as A, the gap between the valve core support 6 and the support guide member 5d is set as B, and the gap between the valve core 2 and the fitting mounting hole 62a of the valve core support 6 is set as C, the relationship between these gaps A to C is set as A < B and A < C. Therefore, in the electric valve 10 of this embodiment, the valve core 2 can be driven to suppress the influence of dimensional deviations of the stepper motor 3 (the external thread portion 32a of the rotor shaft 32 and the internal thread portion 5a of the support member 5, and the joint portion between the rotor shaft 32 and the valve core support 6) and the shaking during driving.

[0051] As explained above, in the electric valve 10 of this embodiment, the valve core 2 is slidably inserted into the valve core support 6 in a state of suspension from the fitting mounting hole 62a at the end of the valve core support 6 located on the valve port 14 side, and the cylindrical valve guide member 1B, configured such that the rod shaft 22 is fixed to the valve body 1, is guided along the axis L. Furthermore, the end of the rotor shaft 32 at the valve port 14 side is slidably inserted into the valve core support 6. Therefore, even if there is wobbling between the rotor shaft 32 and the support member 5, the valve core support 6 is less susceptible to lateral vibration of the rotor shaft 32. Moreover, when the gap between the valve core 2 and the valve guide member 1B is set to A, the gap between the valve core support 6 and the support guide member 5d is set to B, and the gap between the valve core 2 and the fitting mounting hole 62a of the valve core support 6 is set to C, the relationship between these gaps A to C is set to A < B, A < C. Therefore, the valve core 2 can be driven effectively by suppressing dimensional deviations of the stepper motor 3 (the external thread portion 32a of the rotor shaft 32, the internal thread portion 5a of the support member 5, and the joint portion between the rotor shaft 32 and the valve core support 6) and the effects of wobbling during drive. That is, even when the stepper motor 3 (the external thread portion 32a of the rotor shaft 32, the internal thread portion 5a of the support member 5, and the joint portion between the rotor shaft 32 and the valve core support 6) is misaligned, the amount of movement of the valve core 2 is limited by the gap A between the valve core 2 and the valve guide member 1B, thus ensuring concentricity with the valve seat portion 13. In this way, the electric valve 10 according to this embodiment can both ensure the operability of the valve core 2 and suppress valve leakage.

[0052] Furthermore, in the electric valve 10 of this embodiment, when the first connector pipe 101 is mounted on the side of the valve housing component 1A, and the second connector pipe 102 is coaxially arranged with the valve port 14, the flow path between the first connector pipe 101 and the second connector pipe 102 is bent at approximately 90 degrees. As a result, uneven flow velocity is generated around the axis of the valve core 2, and therefore, depending on the state of the fluid, the valve core 2 may vibrate, generating noise. Furthermore, when fluid enters the gap A between the valve core 2 and the valve guide component 1B, depending on the state of the fluid, the valve core 2 may vibrate, generating noise. However, in the case of the above embodiment, since the value of the gap A is sufficiently small, the noise caused by the vibration of these valve core 2 components can be suppressed.

[0053] In this case, it is preferable to set the relationship between gap B and gap C to B < C. Therefore, before the valve core 2 contacts the fitting mounting hole 62a, the radial movement of the valve core support 6 is limited, and thus the valve core 2 is not affected by the radial misalignment of the valve core support 6. That is, the fitting mounting hole 62a and the valve core 2 do not contact each other and do not become sliding resistance.

[0054] Furthermore, preferably, the valve core 2 has a shaft portion guided by the valve guide member 1B, and the guiding amount L1 of the valve core 2 guided by the valve guide member 1B in the axial direction L is set to be longer than the diameter L2 of the aforementioned shaft portion of the valve core 2. Thus, the valve core 2 is guided with sufficient length, thereby reducing valve leakage.

[0055] Next, based on Figure 3 The refrigeration cycle system of the present invention will be described. Figure 3 This is a diagram illustrating an example of the refrigeration cycle system of the present invention. Figure 3 In the diagram, 100 is the expansion valve of the electric valve 10 used in the above-described embodiment, 200 is the outdoor heat exchanger mounted on the outdoor unit, 300 is the indoor heat exchanger mounted on the indoor unit, 400 is the flow path switching valve constituting a four-way valve, and 500 is the compressor. The expansion valve 100, outdoor heat exchanger 200, indoor heat exchanger 300, flow path switching valve 400, and compressor 500 are connected by conduits as shown in the diagram, forming a heat pump refrigeration cycle. The energy storage unit, pressure sensor, temperature sensor, etc., are omitted from the diagram.

[0056] The flow path of the refrigeration cycle is switched between two channels—the flow path during refrigeration operation and the flow path during heating operation—via the flow path switching valve 400. During refrigeration operation, such as... Figure 3 As indicated by the solid arrows, the refrigerant compressed by the compressor 500 flows into the outdoor heat exchanger 200 through the flow path switching valve 400. The outdoor heat exchanger 200 functions as a condenser. The liquid refrigerant flowing out of the outdoor heat exchanger 200 flows into the indoor heat exchanger 300 through the expansion valve 100. The indoor heat exchanger 300 functions as an evaporator.

[0057] On the other hand, during heating operation, such as Figure 3 As indicated by the dashed arrows, the refrigerant compressed by the compressor 500 circulates from the flow path switching valve 400 in the following sequence: indoor heat exchanger 300, expansion valve 100, outdoor heat exchanger 200, flow path switching valve 400, and then compressor 500. The indoor heat exchanger 300 functions as a condenser, and the outdoor heat exchanger 200 functions as an evaporator. The expansion valve 100 depressurizes and expands the liquid refrigerant flowing into the outdoor heat exchanger 200 during cooling operation, or the liquid refrigerant flowing into the indoor heat exchanger 300 during heating operation, further controlling the refrigerant flow rate. Additionally, in Figure 3In this embodiment, the expansion valve 100 is installed in the refrigeration cycle such that, during cooling operation, liquid refrigerant flows from the outdoor heat exchanger 200 into the first connector pipe 101 of the expansion valve 100, and during heating operation, liquid refrigerant from the indoor heat exchanger 300 flows into the second connector pipe 102 of the expansion valve 100. However, it is not limited to this embodiment. The expansion valve 100 can also be installed in the refrigeration cycle such that, during cooling operation, liquid refrigerant from the outdoor heat exchanger 200 flows into the second connector pipe 102 of the expansion valve 100, and during heating operation, liquid refrigerant from the indoor heat exchanger 300 flows into the first connector pipe 101 of the expansion valve 100.

[0058] According to the refrigeration cycle system of the present invention described above, as mentioned above, the electric valve 10, which serves as the expansion valve 100, can both ensure the operability of the valve core 2 and suppress valve leakage by suppressing the effect of shaking during drive and driving the valve core 2. Therefore, it can become a refrigeration cycle system that is energy-saving and difficult to cause adverse conditions during operation.

[0059] Furthermore, the specific structure of the refrigeration cycle system of the present invention is not limited to the embodiments described above, and design changes that do not depart from the spirit of the present invention are also included in the present invention. For example, in the above embodiments, the electric valve 10 is used as the expansion valve of the refrigeration cycle system, but it is not limited to this, and can also be applied to other systems such as throttling devices on the indoor unit side of multi-split air conditioners used in buildings.

Claims

1. An electric valve comprising: The valve body has a valve chamber and a valve port; A valve component that changes the opening degree of the valve port; A drive unit having a drive shaft that drives the valve component forward and backward in the axial direction of the valve port; A support component, which together with the drive shaft, constitutes a threaded feed mechanism; Valve support, which extends over the valve component and the drive shaft; and A support guide that guides the valve support in the axial direction. The rotary motion of the drive unit is converted into linear motion along the axis of the drive shaft using the threaded feed mechanism. The opening degree of the valve port is controlled by the valve component connected to the drive shaft. Its features are, The support component is fixed to the valve body. The valve component and the drive shaft are concentrically configured. The valve component is slidably inserted into the valve bracket in a state of suspension from a fitting mounting hole at the end of the valve bracket located on the valve port side, and is guided in the axial direction by a cylindrical valve guide portion fixed to the valve body. When the gap between the valve component and the valve guide is set as A, the gap between the valve bracket and the bracket guide is set as B, and the gap between the valve component and the fitting mounting hole of the valve bracket is set as C, the relationship between these gaps A and C is set as A < B, A < C. The relationship between the gap B and the gap C is set as B < C.

2. The electric valve according to claim 1, characterized in that, The valve component has a shaft portion that is guided by the valve guide portion. The amount of guidance of the valve component guided by the valve guide in the axial direction is set to be longer than the diameter of the shaft portion of the valve component.

3. A refrigeration cycle system, comprising a compressor, a condenser, an expansion valve, and an evaporator, characterized in that, The electric valve according to claim 1 or 2 is used as the expansion valve.

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