electric valve

Abstract

This invention provides an electric valve that prevents rusting of the silencing components and reduces the impact of foreign matter from the silencing components during peeling, thereby inhibiting corrosion caused by them. The electric valve (10) closes the main valve port (1B) using the main valve core (3) and controls the opening of the secondary valve port (3D) provided on the main valve core (3) using the needle valve (42) of the secondary valve core (4), thereby having a small flow control area that throttles the flow rate of the fluid through the gap between the needle valve (42) and the secondary valve port (3D). A connecting passage (3E) opening toward the main valve chamber (1A) is formed in the main valve core (3), and an annular space (3F) continuously annular about the axis (L) between the connecting passage (3E) and the secondary valve chamber (3B) is formed. A resin silencing component (35, 37) is provided between the connecting passage (3E) and the secondary valve port (3D) to silence the sound of the fluid passing through.

Description

Technical Field

[0001] This invention relates to electric valves used in refrigeration circulation systems and the like. Background Technology

[0002] Conventionally, as an electric valve installed in the refrigeration cycle of an air conditioner, there are known electric valves that control flow in both low-flow and high-flow regions (for example, see Patent Documents 1 and 2). Such conventional electric valves have a main valve core and a secondary valve core, allowing refrigerant (fluid) to flow from the secondary valve core's connecting passage into the secondary valve chamber within the main valve core. Low-flow control is achieved by throttling the refrigerant through a valve port throttling section formed by the gap between the needle valve of the secondary valve core and the secondary valve port.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-106086

[0006] Patent Document 2: Japanese Patent Application Publication No. 2019-128001 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, in conventional electric valves as described in Patent Document 1, when the refrigerant flowing into the connecting path is mixed with the liquid phase in the gas phase and the state of the refrigerant is unstable, if the refrigerant flows into the valve port throttling section unstablely, there is a problem that the refrigerant passing through the valve port throttling section will increase the noise.

[0009] On the other hand, in the electric valve described in Patent Document 2, a silencing component is provided to refine air bubbles in the refrigerant (fluid) flowing in the connecting passage (small flow passage) in order to suppress the aforementioned refrigerant passage noise. However, the silencing component is mainly a porous body formed by sintering metal, laminated wire, or shaped wire, and therefore there is a problem of corrosion caused by the following factors. The main causes of corrosion can be cited as erosion during fluid passage, corrosion from impurities in the piping, corrosion caused by placement in humid environments or saline environments, and corrosion caused by metal foreign objects clogging the valve part when the silencing component is peeled off.

[0010] The purpose of this invention is to provide an electric valve that uses a main valve core to make the main valve port fully closed, and uses the gap between the auxiliary valve port and the auxiliary valve core to control the flow rate in the small flow control area of ​​the fluid. This electric valve can prevent the silencing components from rusting and can reduce the invasion of foreign matter from the valve part when the silencing components are peeled off, thereby suppressing the corrosion caused by them.

[0011] Solution for solving the problem

[0012] The electric valve of the present invention comprises: a valve body constituting a main valve chamber and a main valve port; a main valve core disposed in the main valve chamber and opening and closing the main valve port; and a secondary valve core disposed in a secondary valve chamber formed within the main valve core and movable in the axial direction. The electric valve closes the main valve port using the main valve core and controls the opening degree of the secondary valve port disposed in the main valve core using a needle valve of the secondary valve core, thereby having a small flow control region for throttling the flow rate of fluid through the gap between the needle valve and the secondary valve port. The electric valve is characterized in that a connecting passage opening toward the main valve chamber is formed in the main valve core, and an annular space continuously arranged around the axis between the connecting passage and the secondary valve chamber is formed, and a resin-made silencing member for allowing the fluid to pass through is disposed between the connecting passage and the secondary valve port.

[0013] According to this invention, since the silencing component is made of resin, rust is prevented. Furthermore, due to the low hardness of the raw material, the intrusion of foreign matter during the removal of the silencing component onto the valve section is reduced, thereby inhibiting corrosion caused by such foreign matter. In addition, since the silencing component is made of resin, it offers a high degree of shape freedom and can be mass-produced through resin molding. Moreover, resin materials have superior vibration damping properties compared to metals, thus having a beneficial effect on vibration and maintaining good operational performance.

[0014] In this case, the silencing component is preferably disposed between the annular space and the secondary valve chamber, so that the fluid passes through and thus silences the noise.

[0015] In addition, preferably in the low flow control region, the fluid from the main valve chamber to the main valve port enters the annular space through the connecting path, bends in the axial direction after swirling in the annular space, enters the secondary valve chamber after passing through the silencing component, and is throttled from the secondary valve chamber through the gap between the needle valve and the secondary valve port.

[0016] Furthermore, it is preferable that the annular space has a flow path cross-sectional area larger than the sum of the flow path cross-sectional areas of the connected paths.

[0017] In addition, it is preferable to provide a throttling flow path with a smaller cross-sectional area than the annular space between the annular space and the secondary valve chamber.

[0018] In addition, it is preferable that the secondary valve chamber is provided with an enlarged space whose volume is larger than that of the annular space.

[0019] In addition, it is preferable to provide a fixing component for holding the silencing component inside the main valve core. The fixing component has a first fixing component disposed on the side of the annular space, and the first fixing component is provided with a first through hole communicating with the annular space.

[0020] Furthermore, the first fixing member preferably has a bottom that abuts against the bottom surface of the silencing member and a wall portion that faces the side surface of the silencing member. Also preferably, the first through hole is provided at the bottom, and the height of the wall portion is formed to be smaller than the height of the silencing member, with the side surface of the silencing member protruding further forward than the front end of the wall portion.

[0021] Furthermore, preferably, the fixing member has a second fixing member disposed on the side opposite to the first fixing member, clamping the silencing member, thereby clamping and holding the silencing member from both sides in the axial direction by the first fixing member and the second fixing member. Preferably, the second fixing member is configured to abut against approximately the entire surface of one side of the silencing member and has a second through hole communicating with the secondary valve chamber. Alternatively, the radial width of the second fixing member may be smaller than the radial width of the silencing member, and the second fixing member may be configured to partially abut against one surface of the silencing member.

[0022] In addition, preferably at least one of the first fixing member and the second fixing member is an elastic member.

[0023] Invention Effects

[0024] According to the electric valve of the present invention, since the silencing component used to suppress the sound of refrigerant passing through the electric valve is made of resin, it can prevent rusting. Moreover, since the raw material has low hardness, it can reduce the invasion of foreign matter peeling off the silencing component into the valve part, thereby suppressing the corrosion caused by them. Attached Figure Description

[0025] Figure 1 This is a longitudinal sectional view showing the electric valve according to the first embodiment of the present invention.

[0026] Figure 2 This is an enlarged cross-sectional view showing the main part of the low-flow control region state of the electric valve.

[0027] Figure 3 This is a diagram showing the fluid flow in the low-flow control region of the electric valve.

[0028] Figure 4 This is an enlarged cross-sectional view showing a modified example 1 of the electric valve.

[0029] Figure 5 This is an enlarged cross-sectional view showing a modified example 2 of the electric valve.

[0030] Figure 6 This is an enlarged cross-sectional view showing a modified example 3 of the electric valve.

[0031] Figure 7 This is an enlarged cross-sectional view showing a modified example 4 of the electric valve.

[0032] Figure 8 This is an enlarged cross-sectional view showing the main part of the electric valve according to the second embodiment of the present invention.

[0033] Figure 9 This is a cross-sectional view showing a modified example 5 of the electric valve.

[0034] Figure 10 This is an enlarged cross-sectional view showing a modified example 6 of the electric valve.

[0035] Figure 11 This is an enlarged cross-sectional view showing a modified example 7 of the electric valve.

[0036] Figure 12 This is an enlarged cross-sectional view showing a modified example 8 of the electric valve.

[0037] Figure 13 This is an enlarged cross-sectional view showing a modified example 9 of the electric valve.

[0038] In the picture:

[0039] 1—Valve housing (valve body); 1A—Main valve chamber; 1B—Main valve port; 2—Guiding component; 3—Main valve core; 3B—Secondary valve chamber; 3C—Retaining component; 3D—Secondary valve port; 3E—Connecting path; 3F—Annular space; 3G—Throttling path; 3H—Expanded space; 3J—Bent path; 4—Secondary valve core; 37—Silencing component; 38E—Thrusting hole (throttling path, second connecting path); 39—Throttling component (first fixed component); 39A—Throttling hole (throttling path, first through hole); 42—Needle valve; 60—Fixed component; 61—First fixed component; 61A—Bottom; 61B—Wall; 61C—First through hole (throttling path); 62—Second fixed component; 62A—Second through hole (throttling path). Detailed Implementation

[0040] Embodiments of the electric valve of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a longitudinal sectional view showing the electric valve according to the first embodiment of the present invention. Figure 2 This is an enlarged sectional view showing the main part of the electric valve in the low-flow control range (lower end position of the auxiliary valve). Figure 3 This is a diagram showing the refrigerant (fluid) flow in the low-flow control region of the electric valve. Additionally, the concepts of "upper" and "lower" in the following explanation are different. Figure 1The upper and lower directions correspond to each other. Based on this, the upper and lower directions are sometimes referred to as the axis L direction, and the direction orthogonal to the axis L is referred to as radial. In addition, from the second embodiment onwards, for components and parts that are the same as or similar to those in the first embodiment, common reference numerals are used and descriptions are omitted or simplified.

[0041] The electric valve 10 of this embodiment includes a valve housing 1 as the valve body, a guide member 2, a main valve core 3, a secondary valve core 4, and a drive unit 5.

[0042] The valve body 1 is formed into a generally cylindrical shape, for example, from brass or stainless steel, and has a main valve chamber 1A inside. A first connector pipe 11, which communicates with the main valve chamber 1A, is connected to one side of the outer circumference of the valve body 1, and a second connector pipe 12 is connected to a cylindrical portion extending downward from the lower end. Furthermore, a main valve seat 13 is formed on the main valve chamber 1A side of the second connector pipe 12 of the valve body 1, and the inner side of the main valve seat 13 becomes a main valve port 1B. The main valve port 1B is a cylindrical hole centered on the axis L, and the second connector pipe 12 communicates with the main valve chamber 1A via the main valve port 1B. In this embodiment, the main valve seat 13 is integrally formed with the valve body 1, but it is also possible to separate the valve seat component with the main valve port from the valve body and assemble the valve seat component into the valve body.

[0043] A guide member 2 is installed at the opening at the upper end of the valve housing 1. The guide member 2 has: a fitting portion 21 that fits into the inner circumferential surface of the valve housing 1; a generally cylindrical guide portion 22 located inside the fitting portion 21 and centered on the axis L; a support portion 23 extending above the guide portion 22; a limiting portion 24 located above the support portion 23; and an annular fixing metal member 25, which is composed of a metal plate protruding to the outer periphery of the fitting portion 21. The fitting portion 21, the upper guide portion 22, the support portion 23, and the limiting portion 24 are configured as a single piece made of resin, and the fixing metal member 25 is integrally provided with the resin fitting portion 21 by insertion molding. Alternatively, the fitting portion 21 of the guide member 2 can be pressed into the valve housing 1.

[0044] The guide member 2 is assembled to the valve housing 1 via the fitting part 21 and fixed to the upper end of the valve housing 1 by welding via the fixing metal part 25. Furthermore, in the guide member 2, a cylindrical guide hole 2A coaxial with the axis L is formed inside the fitting part 21 and the guide part 22. Additionally, a through hole 2B coaxial with the guide hole 2A and guiding the rotor shaft 51 (described later) is formed at the center of the support part 23. An internal thread part 2C coaxial with the guide hole 2A and the through hole 2B and threaded with the external thread part 51A of the rotor shaft 51 (described later) is formed at the center of the limiting part 24. Furthermore, a main valve core 3 is disposed within the guide hole 2A, and the main valve core 3 is guided forward and backward along the axis L by the guide hole 2A.

[0045] The main valve core 3 is configured to have a main valve portion 31 that sits and leaves the main valve seat 13, and a retaining portion 32 that serves as a sidewall of the main valve core 3 and holds the secondary valve core 4. A cylindrical opening 3A is formed inside the main valve portion 31. A cylindrical secondary valve chamber 3B is formed inside the retaining portion 32, and a retaining member 3C is provided inside the secondary valve chamber 3B to hold the silencing member 37 (described later) within the main valve core 3. Furthermore, a cylindrical secondary valve port 3D is formed between the main valve portion 31 and the retaining portion 32, opening from the secondary valve chamber 3B toward the opening 3A with the axis L as the center.

[0046] A connecting passage 3E is formed on the side of the holding portion 32 of the main valve core 3, opening toward the main valve chamber 1A in a direction intersecting the axis L. For example... Figure 3 As shown in (A), multiple (e.g., eight) connecting passages 3E are radially formed in a position that is rotationally symmetrical about axis L. The main valve core 3 has a retainer 33 at the upper end of the retaining part 32. In addition, the main valve core 3 has a main valve spring 34 between the retainer 33 and the upper end of the guide hole 2A of the guide member 2. The main valve core 3 is forced towards the main valve seat 13 by the main valve spring 34 (closing direction). In addition, a muffler 35, which will be described later, is provided inside the opening 3A of the main valve part 31. Furthermore, the connecting passages 3E are not limited to being formed radially in a rotationally symmetrical position; the number of connecting passages 3E may be set to one, or multiple passages may be formed at unequal intervals.

[0047] The auxiliary valve core 4 is integrally formed with the lower end of the rotor shaft 51. The auxiliary valve core 4 is configured to have a guide boss 41 and a needle valve 42. Furthermore, the front end of the needle valve 42 of the auxiliary valve core 4 is inserted through the auxiliary valve port 3D in the axial direction L, and a small flow rate is controlled by allowing a small flow of refrigerant through the gap between the needle valve 42 and the auxiliary valve port 3D. A ring-shaped washer 43 made of lubricating resin is provided at the upper end of the guide boss 41, which is inserted into the retaining member 3C. The outer peripheral surface of the guide boss 41 slides in contact with the inner peripheral surface of the retaining member 3C and is guided accordingly. Alternatively, the auxiliary valve core 4 and the rotor shaft 51 can be formed independently and then assembled.

[0048] A housing 14 is airtightly fixed to the upper end of the valve housing 1 by welding or the like, and a drive unit 5 is formed inside and outside the housing 14. The drive unit 5 includes a stepper motor 5A, a threaded feed mechanism 5B that causes the secondary valve core 4 to move forward and backward by rotating the stepper motor 5A, and a limiting mechanism 5C that restricts the rotation of the stepper motor 5A.

[0049] The stepper motor 5A comprises a rotor shaft 51, a magnetic rotor 52 rotatably disposed inside a housing 14, stator coils (not shown) disposed opposite the magnetic rotor 52 on the outer periphery of the housing 14, and other components such as a magnetic yoke and external mounting parts. The rotor shaft 51 is mounted to the center of the magnetic rotor 52 via a bushing, and an external thread portion 51A is formed on the upper outer periphery of the rotor shaft 51. The external thread portion 51A engages with the internal thread portion 2C of the guide member 2. Thus, the guide member 2 supports the rotor shaft 51 on the axis L. Furthermore, the internal thread portion 2C of the guide member 2 and the external thread portion 51A of the rotor shaft 51 constitute a threaded feed mechanism 5B.

[0050] A threaded guide groove 24A is formed on the outer peripheral surface of the limiting portion 24 of the guide member 2. A slider 53 is disposed in the guide groove 24A. The slider 53 abuts against the magnetic rotor 52 and rotates and moves up and down along the guide groove 24A as the magnetic rotor 52 rotates. Furthermore, the slider 53 forms a limiting mechanism 5C that restricts the rotation of the magnetic rotor 52 by abutting against the upper or lower end of the guide groove 24A. Through this limiting mechanism 5C, the lowermost and uppermost positions of the rotor shaft 51 and the magnetic rotor 52 are restricted.

[0051] According to the above structure, when the stepper motor 5A is driven, the magnetic rotor 52 and the rotor shaft 51 rotate. The rotor shaft 51 moves along the axis L together with the magnetic rotor 52 through the threaded feed mechanism 5B of the external threaded part 51A and the internal threaded part 2C. Furthermore, the auxiliary valve core 4 moves forward and backward along the axis L, and the needle valve 42 of the auxiliary valve core 4 approaches or moves away from the auxiliary valve port 3D. Additionally, when the auxiliary valve core 4 rises, the washer 43 engages with the retainer 33 of the main valve core 3 (at the upper end of the auxiliary valve), and the main valve core 3 and the auxiliary valve core 4 move together, with the main valve portion 31 of the main valve core 3 disengaging from the main valve seat 13. As a result, the main valve port 1B is fully open, entering the high-flow-rate region.

[0052] like Figure 2 and Figure 3 As shown, a secondary valve seat 36 is formed around the secondary valve port 3D of the main valve core 3, centered on the axis L. The secondary valve seat 36 is cylindrical and is erected upwards from the opening 3A. A groove-shaped annular space 3F, recessed downwards from the upper surface of the secondary valve seat 36, is formed on the outer periphery of the secondary valve seat 36. The annular space 3F is located radially inside and above the connecting passage 3E, is continuous in a ring around the axis L, and opens upwards. Figure 3As shown in (A), the annular space 3F has an annular flow path cross-sectional area. Furthermore, the annular space 3F has a flow path cross-sectional area larger than the sum of the flow path cross-sectional areas of the eight connecting paths 3E. Additionally, as described later, in order to reliably decelerate the fluid in the annular space 3F, the height of the annular space 3F is preferably greater than or equal to the radius of the connecting paths 3E. A silencing component 37 is provided on the upper side of the annular space 3F, and the upper opening of the annular space 3F is covered by the silencing component 37.

[0053] Here, silencing components are typically composed of porous bodies formed by sintering metal, stacking wires, or molding wires. However, when silencing components are made of metal, the following problems arise: erosion from fluid flow, corrosion from impurities in the piping, corrosion of the silencing component when the electric valve is placed as a single unit in humid or saline environments, or blockage caused by hard metal foreign objects getting stuck in the valve section during silencing component removal.

[0054] Therefore, in the electric valve 10 of this embodiment, the silencing components 35 and 37 are formed of a mesh-like or porous resin material. As the resin material, resins with excellent chemical resistance, such as polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyethylene (PE), and polypropylene (PP), are preferred. The structure is preferably resin sintered (porous), multilayer nonwoven fabric, or diaphragm. Furthermore, in the electric valve 10 of this embodiment, the silencing component 35 is integrally formed in a cylindrical shape, and the silencing component 37 is integrally formed in a ring shape.

[0055] The retaining member 3C is generally cylindrical in shape and includes: a fitting portion 38A, which protrudes radially outward at its upper end and fits into the inner circumferential surface of the main valve core 3; a cylindrical guide portion 38B, which extends along the inner circumferential surface of the main valve core 3 and guides the auxiliary valve core 4 in the direction of axis L; a bottom portion 38C, which extends radially inward from the lower end of the guide portion 38B; and a cylindrical extension portion 38D, which extends downward from the radially inward side of the bottom portion 38C. The retaining member 3C is fixed by fitting the fitting portion 38A into the inner circumferential surface of the main valve core 3, and the bottom portion 38C retains the silencing member 37. In addition, a narrow gap is formed between the lower end of the extension portion 38D and the upper surface of the auxiliary valve seat 36, through which a throttling flow path 3G with a flow path cross-sectional area smaller than that of the annular space 3F is formed.

[0056] exist Figure 2 and Figure 3In the low-flow control range of the electric valve 10 shown, with the main valve core 3 seated in the main valve seat 13, the main valve port 1B is closed. The opening of the auxiliary valve port 3D is controlled by the needle valve 42 of the auxiliary valve core 4 to achieve low-flow control. At this time, the refrigerant flowing from the first connector pipe 11 into the main valve chamber 1A... Figure 3 As shown in (A) and (B), it enters the annular space 3F from the connecting path 3E, rotates within the annular space 3F, bends upwards in the direction of axis L, and then passes through the muffler 37. Furthermore, as... Figure 3 As shown in (C), the refrigerant bends radially inward as it passes through the silencer 37, and enters the secondary valve chamber 3B after passing through the throttling passage 3G. From the secondary valve chamber 3B, it is throttled through the gap between the needle valve 42 and the secondary valve port 3D.

[0057] Figures 4-7 These are enlarged cross-sectional views showing variations 1 to 4 of the electric valve 10 of this embodiment. The difference between these variations 1 to 4 and the aforementioned embodiment lies in maintaining the shape of component 3C and the refrigerant flow path.

[0058] Figure 4 In the modified example 1 shown, the lower end of the extension 38D of the retaining member 3C abuts against the upper surface of the sub-valve seat 36, and a throttling flow path 3G with a flow path cross-sectional area (total) smaller than the annular space 3F is formed by a through hole provided in the middle of the extension 38D. In this modified example 1, as described above, the refrigerant that has passed through the silencing member 37 enters the sub-valve chamber 3B after passing through the throttling flow path 3G, which serves as the through hole.

[0059] Figure 5 In the modified example 2 shown, the lower end of the extension 38D of the retaining member 3C abuts against the upper surface of the sub-valve seat 36. A throttling flow path 3G, formed by a through-hole in the bottom 38C, has a flow path cross-sectional area (total) smaller than the annular space 3F. In this modified example 2, the refrigerant, having passed through the silencing member 37, flows upwards, passes through the throttling flow path 3G (which serves as a through-hole) along the axis L, and enters the sub-valve chamber 3B. Within the sub-valve chamber 3B, it bends radially inwards and flows towards the sub-valve port 3D.

[0060] Figure 6 In the modified example 3 shown, the retaining member 3C lacks a bottom 38C and an extension 38D; instead, the lower end of the guide portion 38B is held in contact with the muffler 37. Furthermore, an enlarged space 3H, with a volume larger than the annular space 3F, is provided in the sub-valve chamber 3B. In this modified example 3, the refrigerant passing through the muffler 37 enters the enlarged space 3H, bends radially inward within the enlarged space 3H, and flows towards the sub-valve port 3D.

[0061] Figure 7In the modified example 4 shown, the lower end of the extension 38D of the retaining member 3C abuts against the upper surface of the sub-valve seat 36, and a through hole 38E serving as a second communication path is provided in the guide portion 38B. In this modified example 4, the refrigerant passing through the silencing member 37 bends radially outward, flows upward in the gap between the inner circumferential surface of the main valve core 3 and the guide portion 38B, and enters the sub-valve chamber 3B after passing radially through the through hole 38E. That is, a curved path 3J that bends radially outward and then bends in the direction of the axis L is provided between the annular space 3F and the sub-valve chamber 3B. In addition, the flow path cross-sectional area of ​​the curved path 3J is smaller than the flow path cross-sectional area of ​​the annular space 3F.

[0062] According to the above embodiment, even when the refrigerant in the main valve chamber 1A is mixed with liquid refrigerant in the gas phase, the refrigerant will be slowed down by passing through the annular space 3F, then through the silencer 37, and after passing through the throttling path 3G, the enlarged space 3H, and the bend path 3J, it will enter the secondary valve chamber 3B and be stabilized. Therefore, the state of the refrigerant in the secondary valve chamber 3B is stabilized, and the sound of the refrigerant passing through the gap between the needle valve 42 and the secondary valve port 3D is reduced, thereby suppressing the generation of noise and vibration of the electric valve 10.

[0063] Furthermore, according to this embodiment, in addition to the aforementioned noise reduction effect, since the noise reduction components 35 and 37 are made of resin, rust can be prevented. Moreover, due to the low hardness of the raw material, the intrusion of foreign matter during the peeling of the noise reduction components 35 and 37 onto the valve section (between the secondary valve seat 36 of the secondary valve port 3D and the needle valve 42 of the secondary valve core 4) can be reduced, thereby suppressing corrosion caused by them. In addition, since the noise reduction components 35 and 37 are made of resin, they offer a high degree of freedom in shape and can be mass-produced through resin molding. Furthermore, resin materials have superior vibration damping properties compared to metals, thus having a beneficial effect on vibration and maintaining good workability.

[0064] Figure 8 This is an enlarged cross-sectional view showing the main parts of the electric valve according to the second embodiment of the present invention. In this second embodiment, the difference from the first embodiment described above lies in maintaining the shape of component 3C and the position of the silencing component 37. For example... Figure 8 As shown, the retaining member 3C includes a fitting portion 38A, a guide portion 38B, a bottom portion 38C, and a cylindrical extension portion 38D extending downward from the middle portion of the bottom portion 38C. The lower end of the extension portion 38D abuts against the upper surface of the sub-valve seat 36, and a throttling flow path with a flow path cross-sectional area (total) smaller than the annular space 3F is formed by a through hole 38E provided in the middle of the extension portion 38D. The silencing member 37 is provided radially inward from the extension portion 38D and is held between the bottom portion 38C of the retaining member 3C and the upper surface of the sub-valve seat 36.

[0065] In such an electric valve, the refrigerant flowing into the main valve chamber 1A is as follows: Figure 8 As shown, the refrigerant enters the annular space 3F from the connecting path 3E, swirls within the annular space 3F, bends upwards along the axis L, then bends radially inwards, and passes through the through hole 38E and the silencing component 37. The refrigerant that has passed through the silencing component 37 enters the secondary valve chamber 3B, and is throttled from the secondary valve chamber 3B through the gap between the needle valve 42 and the secondary valve port 3D.

[0066] Figures 9-11 These are enlarged cross-sectional views showing variations 5 to 7 of the electric valve 10 of this embodiment. The difference between these variations 5 to 7 and the second embodiment lies in the shape of the retaining member 3C and the inclusion of a throttling member 39 that throttles the refrigerant from the annular space 3F. The throttling member 39 is a plate-shaped member that covers the upper opening of the annular space 3F, and has through holes 39A formed at multiple locations in the circumferential direction. That is, the total cross-sectional area of ​​the flow path formed by the through holes 39A is smaller than that of the annular space 3F. These through holes 39A can be provided in the same number and at the same position in the circumferential direction as the connecting passage 3E, or they can be provided at positions offset from the connecting passage 3E in the circumferential direction. The silencing member 37 is held between the retaining member 3C and the upper surface of the throttling member 39. That is, the throttling member 39 also functions as a first fixing member provided on the annular space 3F side of the silencing member 37, and the through holes 39A form the first through holes.

[0067] Figure 9 The retaining member 3C in the modified example 5 shown has a bottom 38C that abuts against the upper surface of the silencing member 37, and the lower surface of the silencing member 37 abuts against the upper surface of the throttling member 39. That is, the bottom 38C pushes the throttling member 39 toward the periphery of the upper opening of the annular space 3F via the silencing member 37. In this modified example 5, the refrigerant from the annular space 3F enters the silencing member 37 after being throttled by the through hole 39A, bends radially inward within the silencing member 37, and then enters the secondary valve chamber 3B. Figure 10 In the modified example 6 shown, the retaining member 3C does not have a bottom 38C, the lower end of the guide portion 38B abuts against the upper surface of the silencing member 37, and the lower surface of the silencing member 37 abuts against the upper surface of the throttling member 39. That is, the guide portion 38B pushes the throttling member 39 towards the periphery of the upper opening of the annular space 3F via the silencing member 37 at its lower end. In this modified example 6, the refrigerant from the annular space 3F enters the silencing member 37 after being throttled by the through hole 39A, and enters the secondary valve chamber 3B after passing upward through the silencing member 37. Figure 11 In the modified example 7 shown, with Figure 9Compared to the previous case, the height (volume) of the silencing component 37 is increased, and the refrigerant is slowed down inside the silencing component 37.

[0068] Figure 12 and Figure 13 These are enlarged cross-sectional views of variations 8 and 9 of the electric valve 10 of this embodiment. In these variations 8 and 9, the inclusion of a fixing member 60 for holding the silencing component 37 differs from the above-described method. The gasket 43 is omitted, and the retaining member 3C is fixed within the retaining portion 32 of the main valve core 3 using a retainer 33. The fixing member 60 has a first fixing member 61 disposed on the annular space 3F side and a second fixing member 62 disposed on the opposite side of the first fixing member 61, clamping the silencing component 37. The fixing member 60 clamps the silencing component 37 from both sides in the direction of the axis L via the first fixing member 61 and the second fixing member 62, and the second fixing member 62 is pressed downwards in the direction of the axis L by the retaining member 3C, which is pressed into the main valve core 3, thereby retaining the silencing component 37.

[0069] The first fixing member 61, when viewed from above, is annular in shape and has a bottom 61A that abuts against the bottom surface of the silencing member 37 and covers the upper opening of the annular space 3F, and a wall portion 61B that faces and abuts against the radially inner side of the silencing member 37, thus forming a roughly L-shaped cross-section. On the bottom 61A of the first fixing member 61, multiple first through holes 61C communicating with the annular space 3F are provided circumferentially. These first through holes 61C function as throttling paths for refrigerant from the annular space 3F, and can be provided in the same number and at the same circumferential position as the connecting path 3E, or they can be provided at positions offset circumferentially from the connecting path 3E. In addition, at least one of the first fixing member 61 and the second fixing member 62 is an elastic member. In the modified examples 8 and 9, the second fixing member 62 is an elastic member that is elastically deformed and flattened in the direction of axis L by being pressed by the holding member 3C, and is pressed on the silencing member 37.

[0070] Figure 12 In the modified example 8 shown, the radial width of the second fixed member 62 is smaller than that of the silencing member 37, and it abuts against the upper surface of the outer periphery of the silencing member 37. The upper surface of the inner periphery of the silencing member 37 is not covered. The refrigerant from the annular space 3F enters the silencing member 37 after being throttled by the first through hole 61C, rises within the silencing member 37, and enters the secondary valve chamber 3B from a position closer to the inner periphery than the second fixed member 62. Within the secondary valve chamber 3B, it bends radially inward. Figure 13In the modified example 9 shown, the second fixing member 62 abuts against almost the entire upper surface of the silencing member 37 and is provided with a second through hole 62A communicating with the secondary valve chamber 3B. Furthermore, the height dimension of the wall portion 61B of the first fixing member 61 is formed to be smaller than the height dimension of the silencing member 37, and the side of the silencing member 37 is exposed above the front end (upper end) of the wall portion 61B. A gap is provided between the upper end of the wall portion 61B and the radially inner end of the second fixing member 62. In this modified example 9, the refrigerant from the annular space 3F enters the silencing member 37 after being throttled through the first through hole 61C, and after passing upward through the silencing member 37, it is again throttled through the second through hole 62A before entering the secondary valve chamber 3B. Additionally, a portion of the refrigerant passing through the silencing member 37 sometimes also enters the secondary valve chamber 3B through the gap between the upper end of the wall portion 61B of the first fixing member 61 and the radially inner end of the second fixing member 62.

[0071] According to the above modifications 8 and 9, the silencing component 37 is held by the first fixing component 61 and the second fixing component 62 of the fixing component 60, thereby improving the retention of the silencing component 37. Furthermore, by having the wall portion 61B of the first fixing component 61 abut against the radially inner side of the silencing component 37, the radial retention of the silencing component 37 can also be improved. In particular, as in modification 9, by branching the flow path into an upward flow path through the silencing component 37 and into the secondary valve chamber 3B via the second through-hole 62A, and a radial flow path through the wall portion 61B (i.e., through the gap between the upper end of the wall portion 61B and the second fixing component 62), the quietness can be improved by dispersing the refrigerant. Moreover, by having the first through-hole 61C function as a throttling flow path with a flow path cross-sectional area (total) smaller than the annular space 3F, the state of the refrigerant in the secondary valve chamber 3B can be stabilized. In addition, at least one of the first fixing member 61 and the second fixing member 62 is made of an elastic member, which allows the muffler member 37 to be pressed and held along the axis L, thereby further improving the retention of the muffler member 37.

[0072] According to the above-described embodiment, the refrigerant is also slowed down through the annular space 3F, and after being throttled by the through holes 38E, 39A, and the first through hole 61C, it enters the secondary valve chamber 3B and is thus stabilized. Furthermore, as in Modification 9, the refrigerant passing through the silencing component 37 is throttled by the second through hole 62A of the second fixing component 62, the gap between the upper end of the wall portion 61B of the first fixing component 61 and the second fixing component 62, and then enters the secondary valve chamber 3B, thereby achieving stabilization. Therefore, the state of the refrigerant in the secondary valve chamber 3B is stabilized, and the sound of the refrigerant passing through the gap between the needle valve 42 and the secondary valve port 3D is reduced, thereby suppressing the generation of noise and vibration of the electric valve 10. Moreover, since the silencing components 35 and 37 are made of resin as described above, the same effect as in the first embodiment can be obtained.

[0073] Furthermore, the present invention is not limited to the embodiments described above, and includes other structures that can achieve the objectives of the present invention, as well as the variations shown below. Additionally, the electric valve of the present invention can also be used in air conditioners such as household air conditioners and commercial air conditioners, and is not limited to air conditioners, but can also be applied to various refrigeration units, etc.

[0074] In the electric valve 10 of the above embodiment, a secondary valve seat 36 and a secondary valve port 3D are integrally formed on the main valve core 3, but it is not limited to this. The valve seat component with the secondary valve port can also be set separately from the main valve core, and the valve seat component can be assembled on the main valve core.

[0075] Furthermore, in the electric valve 10 of the above embodiment, a retaining member 3C is provided inside the main valve core 3, through which the secondary valve core 4 is guided, and the muffler 37 is held. However, it is not limited to this; the guide portion 38B that guides the secondary valve core 4 from the retaining member 3C may be omitted, and the secondary valve core may be guided by the inner circumferential surface of the main valve core. Furthermore, the retaining member that holds the muffler 37 may also be composed of a washer-shaped component.

[0076] In addition, the drive unit 5 of the electric valve 10 in the above embodiment includes a stepper motor 5A, a threaded feed mechanism 5B and a limiting mechanism 5C, but the structure of these parts is not limited to the above embodiment and any form of mechanism can be adopted.

[0077] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the specific structure is not limited to these embodiments, and design changes that do not depart from the spirit of the present invention are also included in the present invention.

Claims

1. An electric valve comprising: The valve body comprises the main valve chamber and the main valve port; The main valve core is disposed in the main valve chamber and opens and closes the main valve port; and The secondary valve core, which is configured to be freely movable in the axial direction within the secondary valve chamber formed within the main valve core, is provided. The electric valve uses the main valve core to close the main valve port, and uses the needle valve of the auxiliary valve core to control the opening of the auxiliary valve port located on the main valve core, thereby having a small flow control region that throttles the fluid flow rate through the gap between the needle valve and the auxiliary valve port. The electric valve is characterized in that... The main valve core has a connecting passage that opens toward the main valve chamber, and an annular space that is continuous around an axis between the connecting passage and the secondary valve chamber. A resin-made silencing component is provided between the connecting passage and the secondary valve port to allow the fluid to pass through. A fixing component for holding the silencing component is provided inside the main valve core. The fixing component has a first fixing component disposed on the side of the annular space, and the first fixing component is provided with a first through hole communicating with the annular space.

2. The electric valve according to claim 1, characterized in that, The silencing component is disposed between the annular space and the secondary valve chamber, allowing the fluid to pass through and thus silencing the noise.

3. The electric valve according to claim 1 or 2, characterized in that, In the low flow control region, the fluid from the main valve chamber to the main valve port enters the annular space through the connecting path, bends in the axial direction after swirling in the annular space, enters the secondary valve chamber after passing through the silencing component, and is throttled from the secondary valve chamber through the gap between the needle valve and the secondary valve port.

4. The electric valve according to claim 1 or 2, characterized in that, The annular space has a flow path cross-sectional area larger than the sum of the flow path cross-sectional areas of the connected paths.

5. The electric valve according to claim 1 or 2, characterized in that, The secondary valve chamber is provided with an enlarged space whose volume is larger than that of the annular space.

6. The electric valve according to claim 1, characterized in that, The first fixing member has a bottom that abuts against the bottom surface of the silencing member and a wall that faces the side surface of the silencing member.

7. The electric valve according to claim 6, characterized in that, The first through hole is provided at the bottom, and the height of the wall portion is formed to be smaller than the height of the silencing component, with the side of the silencing component exposed further forward than the front end of the wall portion.

8. The electric valve according to claim 6 or 7, characterized in that, The fixing component has a second fixing component disposed on the side opposite to the first fixing component, which clamps the silencing component and holds the silencing component from both sides in the axial direction by the first fixing component and the second fixing component.

9. The electric valve according to claim 8, characterized in that, The second fixing component is configured to abut against approximately the entire surface of one side of the silencing component, and is provided with a second through hole communicating with the secondary valve chamber.

10. The electric valve according to claim 9, characterized in that, The radial width dimension of the second fixing member is formed to be smaller than the radial width dimension of the muffler member, and the second fixing member is configured to partially abut against one surface of the muffler member.

11. The electric valve according to claim 8, characterized in that, At least one of the first fixing component and the second fixing component is an elastic component.

12. The electric valve according to claim 9, characterized in that, At least one of the first fixing component and the second fixing component is an elastic component.

13. The electric valve according to claim 10, characterized in that, At least one of the first fixing component and the second fixing component is an elastic component.

14. The electric valve according to claim 1, characterized in that, A secondary valve seat is formed around the secondary valve port, centered on the axis. The annular space is formed on the outer periphery of the sub-valve seat and is a groove that is recessed downwards from the upper surface of the sub-valve seat.

15. The electric valve according to claim 14, characterized in that, The annular space is located radially inside and above the connecting path, is continuous in a ring around the axis, and is formed by opening upwards.

16. The electric valve according to claim 1 or 2, characterized in that, The noise-absorbing component is provided on the upper side of the annular space.

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