JP7576009B2 - Motor-operated valve - Google Patents

Description

The present invention relates to motor-operated valves for use in refrigeration cycle systems, etc.

Conventionally, motorized valves that control flow rate between a small flow rate control region and a large flow rate control region are known as motorized valves installed in the refrigeration cycle of air conditioners (see, for example, Patent Documents 1 and 2). Such conventional motorized valves have a main valve body and a sub-valve body, and perform small flow rate control by allowing refrigerant (fluid) to flow from a communication passage of the sub-valve body into the sub-valve chamber in the main valve body and throttling the refrigerant at the port throttling section, which is the gap between the needle valve of the sub-valve body and the sub-valve port.

JP 2020-106086 A JP 2019-128001 A

However, in conventional motor-operated valves such as that described in Patent Document 1, when the refrigerant flowing into the communication passage is in an unstable state due to a mixture of gas and liquid phases, if the refrigerant flows into the port restriction section while still unstable, the noise of the refrigerant passing through the port restriction section increases.

On the other hand, the motor-operated valve described in Patent Document 2 is equipped with a sound-absorbing member that breaks down bubbles in the refrigerant (fluid) flowing through the communication passage (low-flow passage) in order to suppress the above-mentioned refrigerant passing noise. However, since the sound-absorbing member is mainly a porous body made of sintered metal or laminated wire or molded wire, there is a problem that corrosion occurs due to the following factors. Causes of corrosion include erosion when fluid passes through or impurities in the piping, being left in a humid environment or salt damage environment, and metal foreign matter that becomes stuck in the valve when the sound-absorbing member peels off.

The object of the present invention is to provide an electrically operated valve that fully closes the main valve port with the main valve body and controls the flow rate of the fluid in a small flow rate control range by the gap between the sub-valve body and the sub-valve port provided on the main valve body, and that can prevent rust from occurring in the sound absorbing material, reduce the aggressiveness of the flaking foreign matter against the valve part when the sound absorbing material peels off, and suppress corrosion caused by these.

The motor-operated valve of the present invention comprises a valve body constituting a main valve chamber and a main valve port, a main valve element provided within the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed within the main valve element so as to be movable in the axial direction, and the main valve element closes the main valve port, and the opening of the sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby providing a small flow rate control region for throttling the flow rate of fluid in a gap between the needle valve and the sub-valve port. The main valve element has a small flow rate control region for throttling the flow rate of fluid in a gap between the needle valve and the sub-valve port. a communication passage opening through the communication passage and an annular space continuing annularly around the axis between the communication passage and the sub-valve port, and a resin sound-absorbing member through which the fluid passes is provided between the communication passage and the sub-valve port , and in the small flow rate control region, the fluid flowing from the main valve chamber to the main valve port enters the annular space from the communication passage, swirls in the annular space and then bends in the axial direction, passes through the sound-absorbing member before entering the sub-valve chamber, and is throttled from the sub-valve chamber by a gap between the needle valve and the sub-valve port .
Moreover, the motor-operated valve of the present invention comprises a valve body constituting a main valve chamber and a main valve port, a main valve element provided within the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed within the main valve element so as to be freely movable in the axial direction, and the main valve element closes the main valve port, and the opening degree of the sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby providing a small flow rate control region for throttling the flow rate of fluid in a gap between the needle valve and the sub-valve port, wherein the main valve element is formed with a communication passage opening toward the main valve chamber, and an annular space continuing annularly around the axis between the communication passage and the sub-valve chamber, a resin sound absorbing member is provided between the communication passage and the sub-valve port, and a throttling passage having a flow path cross-sectional area smaller than that of the annular space is provided between the annular space and the sub-valve chamber.
Moreover, the motor-operated valve of the present invention comprises a valve body constituting a main valve chamber and a main valve port, a main valve element provided in the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed in the main valve element and movable in the axial direction, wherein the main valve element closes the main valve port, and the opening degree of the sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby having a small flow control range in which the flow rate of fluid is restricted in a gap between the needle valve and the sub-valve port, wherein the main valve element has a communication passage opening toward the main valve chamber, and an annular space continuing in an annular shape around the axis between the communication passage and the sub-valve chamber, a resin sound-absorbing member that allows the fluid to pass therethrough is provided between the communication passage and the sub-valve port, and a fixing member for holding the sound-absorbing member is provided within the main valve element, the fixing member has a first fixing member provided on the annular space side, and the first fixing member has a first through-hole communicating with the annular space.

According to the present invention, since the sound-absorbing member is made of resin, rust can be prevented, and since the hardness of the material is low, the aggressiveness of the detached foreign matter to the valve portion when the sound-absorbing member peels off can be reduced, and corrosion caused by these factors can be suppressed. In addition, since the sound-absorbing member is made of resin, there is a high degree of freedom in the shape, and it can be produced in large quantities by resin molding. Furthermore, since resin materials have better vibration-damping properties than metals, they are advantageous against the effects of vibration, and good operability can be maintained.

In this case, it is preferable that the sound-absorbing member is disposed between the annular space and the sub-valve chamber, and absorbs sound by allowing the fluid to pass through.

Furthermore, it is preferable that the annular space has a flow passage cross-sectional area larger than the sum of the flow passage cross-sectional areas of the communication passages.

It is also preferable that the sub-valve chamber is provided with an expanded space whose volume is larger than that of the annular space.

Furthermore, it is preferable that the first fixing member has a bottom portion that abuts against the bottom surface of the sound deadening member and a wall portion that faces the side surface of the sound deadening member. Furthermore, it is preferable that the first through hole is provided in the bottom portion, the height dimension of the wall portion is formed smaller than the height dimension of the sound deadening member, and the side surface of the sound deadening member beyond the tip of the wall portion is exposed.

Furthermore, it is preferable that the fixed member has a second fixed member provided on the opposite side of the first fixed member with the sound absorbing member sandwiched therebetween, and that the first fixed member and the second fixed member sandwich and hold the sound absorbing member from both sides in the axial direction. Furthermore, it is preferable that the second fixed member is provided in contact with substantially the entire surface of one surface of the sound absorbing member, and that a second through hole communicating with the auxiliary valve chamber is provided. In addition, the radial width dimension of the second fixed member is formed smaller than the radial width dimension of the sound absorbing member, and the second fixed member may be provided in partial contact with one surface of the sound absorbing member.

It is also preferable that at least one of the first fixing member and the second fixing member is an elastic member.

According to the motor-operated valve of the present invention, the sound-absorbing member for suppressing the sound of the refrigerant passing through the motor-operated valve is made of resin, which prevents rust from occurring. In addition, the low hardness of the material reduces the aggressiveness of foreign matter that peels off the sound-absorbing member against the valve part, thereby suppressing corrosion caused by these factors.

1 is a vertical cross-sectional view showing a motor-operated valve according to a first embodiment of the present invention; FIG. 4 is an enlarged cross-sectional view showing a main portion of the motor-operated valve in a small flow rate control range state. FIG. 4 is a diagram showing the flow of fluid in a small flow rate control range state of the motor-operated valve. FIG. 4 is an enlarged cross-sectional view showing a first modified example of the motor-operated valve. FIG. 4 is an enlarged cross-sectional view showing a second modified example of the motor-operated valve. FIG. 11 is an enlarged cross-sectional view showing a third modified example of the motor-operated valve. FIG. 10 is an enlarged cross-sectional view showing a fourth modified example of the motor-operated valve. FIG. 5 is an enlarged cross-sectional view showing a main portion of a motor-operated valve according to a second embodiment of the present invention. FIG. 11 is a cross-sectional view showing a fifth modified example of the motor-operated valve. FIG. 13 is an enlarged cross-sectional view showing a sixth modified example of the motor-operated valve. FIG. 13 is an enlarged cross-sectional view showing a seventh modified example of the motor-operated valve. FIG. 13 is an enlarged cross-sectional view showing a modified example 8 of the motor-operated valve. FIG. 13 is an enlarged cross-sectional view showing a modified example 9 of the motor-operated valve.

The embodiments of the motor-operated valve of the present invention will be described with reference to the drawings. Fig. 1 is a longitudinal cross-sectional view showing the motor-operated valve of the first embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view showing the main parts of the motor-operated valve in the small flow control range state (sub-valve lower end position), and Fig. 3 is a diagram showing the flow of refrigerant (fluid) in the small flow control range state of the motor-operated valve. Note that the concepts of "up and down" in the following description correspond to the up and down in Fig. 1, and the up and down directions are sometimes referred to as the axial L direction, and the direction perpendicular to the axial L is sometimes referred to as the radial direction. Also, in the second and subsequent embodiments described below, common reference numerals are used for members and parts that are the same as or similar to those of the first embodiment, and descriptions may be omitted or simplified.

The motor-operated valve 10 of this embodiment includes a valve housing 1, which is the valve body, a guide member 2, a main valve body 3, a sub-valve body 4, and a drive unit 5.

The valve housing 1 is formed in a substantially cylindrical shape from, for example, brass or stainless steel, and has a main valve chamber 1A inside. A first joint pipe 11 that is connected to the main valve chamber 1A is connected to one side of the outer periphery of the valve housing 1, and a second joint pipe 12 is connected to a cylindrical portion extending downward from the lower end. A main valve seat 13 is formed on the main valve chamber 1A side of the second joint pipe 12 of the valve housing 1, and the inside of this main valve seat 13 is the main valve port 1B. The main valve port 1B is a cylindrical hole centered on the axis L, and the second joint pipe 12 is connected to the main valve chamber 1A through the main valve port 1B. In this embodiment, the main valve seat 1B is formed integrally with the valve housing 1, but a valve seat member having a main valve port may be provided separately from the valve housing, and the valve seat member may be assembled to the valve housing.

The guide member 2 is attached to 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 peripheral surface of the valve housing 1, a guide portion 22 that is located inside the fitting portion 21 and has a substantially cylindrical shape centered on the axis L, a holder portion 23 that extends from the upper portion of the guide portion 22, a stopper portion 24 that is provided above the holder portion 23, and a ring-shaped fixing metal fitting 25 made of a metal plate that protrudes from the outer periphery of the fitting portion 21. The fitting portion 21, the upper guide portion 22, the holder portion 23, and the stopper portion 24 are configured as an integrated resin product, and the fixing metal fitting 25 is provided integrally with the resin fitting portion 21 by insert molding. The fitting portion 21 of the guide member 2 may be press-fitted into the valve housing 1.

The guide member 2 is assembled to the valve housing 1 by the fitting portion 21, and is fixed to the upper end of the valve housing 1 by welding via a fixing bracket 25. In addition, a cylindrical guide hole 2A is formed on the inside of the fitting portion 21 and the guide portion 22 of the guide member 2, which is coaxial with the axis L. In addition, a through hole 2B is formed in the center of the holder portion 23, which is coaxial with the guide hole 2A and guides the rotor shaft 51 described later. In the center of the stopper portion 24, a female thread portion 2C is formed, which is coaxial with the guide hole 2A and the through hole 2B, and screws into the male thread portion 51A of the rotor shaft 51 described later. The main valve body 3 is disposed in the guide hole 2A, and the main valve body 3 is guided forward and backward in the axis L direction by the guide hole 2A.

The main valve body 3 is configured to have a main valve portion 31 that seats and unseats on the main valve seat 13, and a retaining portion 32 that is the side wall of the main valve body 3 and retains the sub-valve body 4. A cylindrical opening 3A is formed inside the main valve portion 31. A cylindrical sub-valve chamber 3B is formed inside the retaining portion 32, and a retaining member 3C is provided inside this sub-valve chamber 3B to retain a sound-absorbing member 37 (described later) inside the main valve body 3. A cylindrical sub-valve port 3D is formed between the main valve portion 31 and the retaining portion 32, opening from the sub-valve chamber 3B to the opening 3A side with the axis L as the center.

A communication passage 3E is formed on the side of the retaining portion 32 of the main valve body 3, opening toward the main valve chamber 1A in a direction intersecting the axis L. As shown in FIG. 3A, a plurality of (e.g., eight) communication passages 3E are formed radially at rotationally symmetric positions around the axis L. The main valve body 3 has a retainer 33 at the upper end of the retaining portion 32. The main valve body 3 also 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 body 3 is biased toward the main valve seat 13 (closing direction) by the main valve spring 34. A sound-deadening member 35, which will be described later, is disposed inside the opening 3A of the main valve portion 31. The communication passages 3E are not limited to being formed radially at rotationally symmetric positions, and the number of communication passages 3E may be one or multiple communication passages may be formed at unequal intervals.

The sub-valve body 4 is integrally provided at the lower end of the rotor shaft 51. The sub-valve body 4 is configured with a guide boss portion 41 and a needle valve 42. The tip of the needle valve 42 of the sub-valve body 4 is inserted in the axial direction L into the sub-valve port 3D, and a small flow rate of refrigerant is controlled by flowing through the gap between the needle valve 42 and the sub-valve port 3D. A ring-shaped washer 43 made of lubricating resin is disposed at the upper end of the guide boss portion 41, and the guide boss portion 41 is inserted into the holding member 3C. The outer peripheral surface of the guide boss portion 41 is guided by sliding against the inner peripheral surface of the holding member 3C. The sub-valve body 4 and the rotor shaft 51 may be formed separately and then assembled.

A case 14 is fixed airtightly to the upper end of the valve housing 1 by welding or the like, and the drive unit 5 is configured inside and outside this case 14. The drive unit 5 includes a stepping motor 5A, a screw feed mechanism 5B that moves the sub-valve body 4 forward and backward by the rotation of the stepping motor 5A, and a stopper mechanism 5C that restricts the rotation of the stepping motor 5A.

The stepping motor 5A is composed of a rotor shaft 51, a magnet rotor 52 rotatably arranged inside the case 14, a stator coil (not shown) arranged facing the magnet rotor 52 on the outer periphery of the case 14, and other components such as a yoke and an exterior member. The rotor shaft 51 is attached to the center of the magnet rotor 52 via a bush, and a male thread 51A is formed on the outer periphery of the upper part of the rotor shaft 51. The male thread 51A is screwed into the female thread 2C of the guide member 2. As a result, the guide member 2 supports the rotor shaft 51 on the axis L. The female thread 2C of the guide member 2 and the male thread 51A of the rotor shaft 51 form the screw feed mechanism 5B.

A male-threaded guide groove 24A is formed on the outer circumferential surface of the stopper portion 24 of the guide member 2. A slider 53 is provided in the guide groove 24A. The slider 53 abuts against the magnet rotor 52, and rotates and moves up and down along the guide groove 24A as the magnet rotor 52 rotates. The slider 53 abuts against the upper or lower end of the guide groove 24A, thereby forming a stopper mechanism 5C that restricts the rotation of the magnet rotor 52. This stopper mechanism 5C restricts the lowermost and uppermost positions of the rotor shaft 51 and the magnet rotor 52.

When the stepping motor 5A is driven, the magnet rotor 52 and rotor shaft 51 rotate, and the rotor shaft 51 moves in the axial direction L together with the magnet rotor 52 due to the screw feed mechanism 5B between the male thread portion 51A and the female thread portion 2C. Then, the sub-valve body 4 moves forward and backward in the axial direction L, and the needle valve 42 of the sub-valve body 4 approaches or moves away from the sub-valve port 3D. In addition, when the sub-valve body 4 rises, the washer 43 engages with the retainer 33 of the main valve body 3 (sub-valve upper end position), and the main valve body 3 moves together with the sub-valve body 4, and the main valve portion 31 of the main valve body 3 leaves the main valve seat 13. As a result, the main valve port 1B is fully opened and in a large flow rate range state.

2 and 3, a sub-valve seat 36 is formed around the sub-valve port 3D of the main valve body 3, with the axis L as the center. The sub-valve seat 36 is formed in a cylindrical shape and is provided rising upward from the opening 3A. A groove-shaped annular space 3F is formed on the outer periphery of the sub-valve seat 36, which is recessed below the upper surface of the sub-valve seat 36. The annular space 3F is located radially inside and above the communication passage 3E, is continuous around the axis L, and is formed to open upward. As shown in FIG. 3(A), the annular space 3F has an annular flow passage cross-sectional area. The annular space 3F has a flow passage cross-sectional area larger than the total flow passage cross-sectional area of the eight communication passages 3E. In order to reliably decelerate the fluid in the annular space 3F as described later, it is preferable that the height of the annular space 3F is equal to or larger than the radius of the communication passage 3E. A sound-deadening member 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 sound-deadening member 37.

Generally, sound-absorbing materials are mainly made of porous bodies such as sintered metal, laminated wire, or molded wire. However, when sound-absorbing materials are made of metal materials, the following problems are of concern. These problems include erosion when fluid passes through, corrosion caused by impurities in the piping, corrosion of the sound-absorbing material when the motor-operated valve is left alone in a humid or salt-damaged environment, and problems such as hard metal foreign objects becoming caught in the valve when the sound-absorbing material peels off, causing blockages.

Therefore, in the motor-operated valve 10 of this embodiment, the sound-absorbing members 35, 37 are formed from a mesh-like or porous resin material. Resin materials with excellent chemical resistance, such as polytetrafluoroethylene resin (PTFE resin: Poly Tetra Fluoro Ethylene), polyphenylene sulfide resin (PPS resin: Poly Phenylene Sulfide Resin), polyethylene resin (PE resin: Poly Ethylene (USA), Poly Ethene (UK)), and polypropylene resin (PP resin: Poly Propylene), are preferred, and the materials are preferably sintered resin (porous), multilayer nonwoven fabric, membrane, or the like. In addition, in the motor-operated valve 10 of this embodiment, the sound-absorbing member 35 is formed in a cylindrical shape as a whole, and the sound-absorbing member 37 is formed in a ring shape as a whole.

The retaining member 3C is generally cylindrical and includes a fitting portion 38A that protrudes radially outward at its upper end and fits into the inner circumferential surface of the main valve body 3, a cylindrical guide portion 38B that extends along the inner circumferential surface of the main valve body 3 and guides the sub-valve body 4 in the direction of the axis L, a bottom portion 38C that extends radially inward from the lower end of the guide portion 38B, and a cylindrical extension portion 38D that extends downward from the radially inner 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 body 3, and the sound-absorbing member 37 is held by the bottom portion 38C. In addition, a narrow gap is formed between the lower end of the extension portion 38D and the upper surface of the sub-valve seat 36, and this gap forms a throttle passage 3G with a flow passage cross-sectional area smaller than that of the annular space 3F.

In the low flow control range state of the motor-operated valve 10 shown in Figures 2 and 3, the main valve body 3 is seated on the main valve seat 13, the main valve port 1B is closed, and the needle valve 42 of the sub-valve body 4 controls the opening of the sub-valve port 3D to control the low flow rate. At this time, the refrigerant that flows into the main valve chamber 1A from the first joint pipe 11 enters the annular space 3F from the communication passage 3E as shown in Figures 3(A) and (B), turns in the annular space 3F, bends upward in the direction of the axis L, and passes through the muffling member 37. Furthermore, as shown in Figure 3(C), the refrigerant bends radially inward while passing through the muffling member 37, passes through the throttling passage 3G, enters the sub-valve chamber 3B, and is throttled from the sub-valve chamber 3B by the gap between the needle valve 42 and the sub-valve port 3D.

Figures 4 to 7 are enlarged cross-sectional views showing variants 1 to 4 of the motor-operated valve 10 of this embodiment, respectively. Variations 1 to 4 differ from the previously described embodiment in the shape of the retaining member 3C and the flow path of the refrigerant.

The retaining member 3C of the modified example 1 shown in FIG. 4 is provided with the lower end of the extension portion 38D abutting against the upper surface of the sub-valve seat 36, and a through hole provided in the middle of the extension portion 38D forms a throttle passage 3G whose flow path cross-sectional area (total) is smaller than that of the annular space 3F. In this modified example 1, as in the above, the refrigerant that has passed through the sound absorbing member 37 passes through the throttle passage 3G, which is a through hole, before entering the sub-valve chamber 3B.

The retaining member 3C of the second modified example shown in FIG. 5 is provided with the lower end of the extension portion 38D abutting against the upper surface of the sub-valve seat 36, and a through hole provided in the bottom portion 38C forms a throttle passage 3G whose flow path cross-sectional area (total) is smaller than that of the annular space 3F. In this second modified example, the refrigerant that has passed through the muffling member 37 flows upward, passes through the throttle passage 3G, which is a through hole, in the direction of the axis L, enters the sub-valve chamber 3B, bends radially inward within the sub-valve chamber 3B, and then flows into the sub-valve port 3D.

The retaining member 3C of the modified example 3 shown in FIG. 6 does not include the bottom portion 38C and the extension portion 38D, and the lower end of the guide portion 38B is held in contact with the sound-absorbing member 37. The sub-valve chamber 3B is provided with an expanded space 3H whose volume is larger than that of the annular space 3F. In this modified example 3, the refrigerant that passes through the sound-absorbing member 37 enters the expanded space 3H, bends radially inward within the expanded space 3H, and then flows to the sub-valve port 3D.

In the retaining member 3C of the modified example 4 shown in FIG. 7, the lower end of the extension portion 38D is provided in contact with the upper surface of the sub-valve seat 36, and the guide portion 38B is provided with a through hole 38E as a second communication passage. In this modified example 4, the refrigerant that passes through the sound absorbing member 37 bends radially outward, flows upward through the gap between the inner circumferential surface of the main valve body 3 and the guide portion 38B, passes radially through the through hole 38E, and then enters the sub-valve chamber 3B. That is, between the annular space 3F and the sub-valve chamber 3B, a bent path 3J is provided that bends radially outward and further bends in the direction of the axis L. The flow path cross-sectional area of the bent path 3J is smaller than the flow path cross-sectional area of the annular space 3F.

According to the present embodiment described above, even if the refrigerant in the main valve chamber 1A is in a state where liquid phase refrigerant is mixed with gas phase refrigerant, this refrigerant is decelerated by passing through the annular space 3F, and then passes through the sound-deadening member 37, and then through the throttling passage 3G, the enlarged space 3H, and the bent passage 3J before entering the sub-valve chamber 3B, where it is stabilized. Therefore, the state of the refrigerant in the sub-valve chamber 3B is stabilized, and the refrigerant passing sound when passing through the gap between the needle valve 42 and the sub-valve port 3D is reduced, and the generation of noise and vibration of this motor-operated valve 10 can be suppressed.

In addition to the above-mentioned sound-proofing effect, the sound-proofing members 35, 37 are made of resin, which prevents rust from occurring. Furthermore, the low hardness of the material reduces the aggressiveness of foreign matter that peels off from the valve portion (between the sub-valve seat 36 of the sub-valve port 3D and the needle valve 42 of the sub-valve body 4) when the sound-proofing members 35, 37 peel off, thereby suppressing corrosion caused by these. In addition, because the sound-proofing members 35, 37 are made of resin, there is a high degree of freedom in the shape, and they can be manufactured in large quantities by resin molding. Furthermore, resin materials have better vibration-damping properties than metals, which makes them advantageous against the effects of vibration and allows good operability to be maintained.

Figure 8 is an enlarged cross-sectional view showing the main part of the motor-operated valve of the second embodiment of the present invention. The second embodiment differs from the first embodiment in the shape of the holding member 3C and the position of the sound-absorbing member 37. As shown in Figure 8, the holding member 3C has 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 is provided in contact with the upper surface of the auxiliary valve seat 36, and a through hole 38E provided in the middle of the extension portion 38D forms a throttle passage having a smaller flow path cross-sectional area (total) than the annular space 3F. The sound-absorbing member 37 is provided radially inward from the extension portion 38D and is held between the bottom portion 38C of the holding member 3C and the upper surface of the auxiliary valve seat 36.

In this type of motor-operated valve, as shown in FIG. 8, the refrigerant that flows into the main valve chamber 1A enters the annular space 3F from the communication passage 3E, swirls in the annular space 3F, bends upward in the direction of the axis L, then bends radially inward, passes through the through hole 38E, and then passes through the muffling member 37. The refrigerant that passes through the muffling member 37 enters the sub-valve chamber 3B, and is throttled from the sub-valve chamber 3B by the gap between the needle valve 42 and the sub-valve port 3D.

9 to 11 are enlarged cross-sectional views showing modified examples 5 to 7 of the motor-operated valve 10 of this embodiment, respectively. The differences between these modified examples 5 to 7 and the second embodiment are the shape of the holding member 3C and the inclusion of a throttle member 39 that throttles the refrigerant from the annular space 3F. The throttle member 39 is a plate-shaped member provided to cover the upper opening of the annular space 3F, and has through holes 39A that penetrate vertically at multiple locations in the circumferential direction. That is, the through holes 39A form a throttle passage whose flow path cross-sectional area (total) is smaller than that of the annular space 3F. These through holes 39A may be provided in the same number as the communication passage 3E at the same circumferential position, or may be provided at a position shifted from the communication passage 3E in the circumferential direction. The sound-deadening member 37 is held between the holding member 3C and the upper surface of the throttle member 39. That is, the throttle member 39 also functions as a first fixed member provided on the annular space 3F side of the sound-deadening member 37, and the through holes 39A form a first through hole.

The retaining member 3C of the modified example 5 shown in FIG. 9 has a bottom 38C, and the bottom 38C abuts against the upper surface of the muffling member 37, and the lower surface of the muffling member 37 abuts against the upper surface of the throttling member 39. That is, the bottom 38C presses the throttling member 39 toward the periphery of the upper opening of the annular space 3F through the muffling member 37. In this modified example 5, the refrigerant from the annular space 3F is throttled by the through hole 39A before entering the muffling member 37, and then bends radially inward inside the muffling member 37 and passes through it before entering the auxiliary valve chamber 3B. The retaining member 3C of the modified example 6 shown in FIG. 10 does not have a bottom 38C, and the lower end of the guide portion 38B abuts against the upper surface of the muffling member 37, and the lower surface of the muffling member 37 abuts against the upper surface of the throttling member 39. That is, the guide portion 38B presses the throttling member 39 toward the periphery of the upper opening of the annular space 3F through the muffling member 37 at its lower end. In this modification 6, the refrigerant from the annular space 3F is throttled by the through hole 39A before entering the muffling member 37, passing upward through the muffling member 37 before entering the sub-valve chamber 3B. In modification 7 shown in FIG. 11, the height dimension (volume) of the muffling member 37 is larger than in FIG. 9, and the refrigerant is decelerated inside the muffling member 37.

12 and 13 are enlarged cross-sectional views showing modified examples 8 and 9 of the motor-operated valve 10 of this embodiment, respectively. These modified examples 8 and 9 differ from the above-mentioned embodiment in that they include a fixing member 60 that holds the silencing member 37, the above-mentioned washer 43 is omitted, and the holding member 3C is fixed in the holding portion 32 of the main valve body 3 by the retainer 33. The fixing member 60 has a first fixing member 61 provided on the annular space 3F side inside the main valve body 3, and a second fixing member 62 provided on the opposite side of the first fixing member 61 with the silencing member 37 in between. The fixing member 60 holds the silencing member 37 by sandwiching it between the first fixing member 61 and the second fixing member 62 from both sides in the axial line L direction, and by pressing the second fixing member 62 downward in the axial line L direction by the holding member 3C pressed into the main valve body 3.

The first fixing member 61 is formed in a circular ring shape in a plan view, and has a bottom portion 61A that abuts against the bottom surface of the sound deadening member 37 and covers the upper opening of the annular space 3F, and a wall portion 61B that abuts against the radially inner side surface of the sound deadening member 37, and is formed to have a substantially L-shaped cross section. The bottom portion 61A of the first fixing member 61 has first through holes 61C that communicate with the annular space 3F provided at multiple locations along the circumferential direction. These first through holes 61C function as throttle passages that throttle the refrigerant from the annular space 3F, and may be provided at the same circumferential position as the communication passages 3E in number, or may be provided at a position shifted from the communication passages 3E in the circumferential direction. At least one of the first fixing member 61 and the second fixing member 62 is an elastic member, and in these modified examples 8 and 9, the second fixing member 62 is an elastic member, and is pressed against the sound deadening member 37 while being elastically deformed and crushed in the axial direction L by being pressed against the holding member 3C.

The radial width dimension of the second fixed member 62 of the modified example 8 shown in Fig. 12 is formed smaller than the radial width dimension of the sound deadening member 37, and abuts against the upper surface of the outer periphery side of the sound deadening member 37. The upper surface of the inner periphery side of the sound deadening member 37 is not covered, and the refrigerant from the annular space 3F is squeezed by the first through hole 61C before entering the sound deadening member 37, rising inside the sound deadening member 37, entering the auxiliary valve chamber 3B from the inner periphery side of the second fixed member 62, and bending radially inward in the auxiliary valve chamber 3B. The second fixed member 62 of the modified example 9 shown in Fig. 13 is provided in abutment against almost the entire upper surface of the sound deadening member 37, and is provided with a second through hole 62A that communicates with the auxiliary valve chamber 3B. In addition, the height dimension of the wall portion 61B of the first fixed member 61 is formed smaller than the height dimension of the sound absorbing member 37, the side of the sound absorbing member 37 above the tip portion (upper end portion) of the wall portion 61B is exposed, and a gap is provided between the upper end portion of the wall portion 61B and the radial inner end portion of the second fixed member 62. In this modification example 9, the refrigerant from the annular space 3F is throttled by the first through hole 61C before entering the sound absorbing member 37, passes upward through the sound absorbing member 37, and is throttled again by the second through hole 62A before entering the auxiliary valve chamber 3B. In addition, some of the refrigerant that passes through the sound absorbing member 37 may enter the auxiliary valve chamber 3B through the gap between the upper end portion of the wall portion 61B of the first fixed member 61 and the radial inner end portion of the second fixed member 62.

According to the above-mentioned modified examples 8 and 9, the sound deadening member 37 is sandwiched and held by the first fixing member 61 and the second fixing member 62 of the fixing member 60, so that the retention of the sound deadening member 37 can be improved. In addition, the wall portion 61B of the first fixing member 61 abuts against the radially inner side surface of the sound deadening member 37, so that the retention of the sound deadening member 37 in the radial direction can also be improved. In particular, as in modified example 9, the refrigerant is dispersed by branching into a flow path that passes upward through the sound deadening member 37 and enters the auxiliary valve chamber 3B through the second through hole 62A, and a flow path that passes radially through the wall portion 61B (i.e., through the gap between the upper end portion of the wall portion 61B and the second fixing member 62) and enters the auxiliary valve 3B, so that quietness can be improved. Furthermore, the first through hole 61C functions as a throttle passage whose flow path cross-sectional area (total) is smaller than that of the annular space 3F, so that the state of the refrigerant in the auxiliary valve chamber 3B is stabilized. Furthermore, since at least one of the first fixing member 61 and the second fixing member 62 is made of an elastic material, the sound-absorbing member 37 can be pressed and held in the direction of the axis L, thereby further improving the retention of the sound-absorbing member 37.

In the present embodiment, the refrigerant is decelerated by passing through the annular space 3F, and is then throttled by the through holes 38E, 39A and the first through hole 61C before passing through the sound-deadening member 37 and entering the auxiliary valve chamber 3B, where it is stabilized. Furthermore, as in the ninth modification, the refrigerant that has passed through the sound-deadening member 37 is throttled by the second through hole 62A of the second fixed member 62 and the gap between the upper end of the wall portion 61B of the first fixed member 61 and the second fixed member 62, and then enters the auxiliary valve chamber 3B, where it is stabilized. Therefore, the state of the refrigerant in the auxiliary valve chamber 3B is stabilized, the refrigerant passing sound when passing through the gap between the needle valve 42 and the auxiliary valve port 3D is reduced, and the generation of noise and vibration of the motor-operated valve 10 can be suppressed. Moreover, since the sound-deadening members 35, 37 are made of resin as described above, it is possible to obtain the same effect as in the first embodiment.

The present invention is not limited to the above-described embodiment, but includes other configurations that can achieve the object of the present invention, and the following modifications are also included in the present invention. The motor-operated valve of the present invention may be used in air conditioners such as home air conditioners and commercial air conditioners, and is not limited to air conditioners and can also be applied to various types of refrigeration machines, etc.

In the motor-operated valve 10 of the above embodiment, the sub-valve seat 36 and the sub-valve port 3D are formed integrally with the main valve body 3, but this is not limited thereto. A valve seat member having a sub-valve port may be provided separately from the main valve body, and the valve seat member may be assembled to the main valve body.

In addition, in the motor-operated valve 10 of the above embodiment, a retaining member 3C is provided inside the main valve body 3, and this retaining member 3C guides the sub-valve body 4 and retains the sound-absorbing member 37. However, this is not limited to the above, and the guide portion 38B that guides the sub-valve body 4 from the retaining member 3C may be eliminated, and the sub-valve body may be guided by the inner peripheral surface of the main valve body. Furthermore, the retaining member that holds the sound-absorbing member 37 may be composed of a washer-shaped member.

In addition, the drive unit 5 of the motor-operated valve 10 in the above embodiment includes a stepping motor 5A, a screw feed mechanism 5B, and a stopper mechanism 5C, but the configuration of each of these components is not limited to that of the above embodiment, and any type of mechanism can be used.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes design changes that do not deviate from the gist of the present invention.

1 Valve housing (valve body)
Reference Signs List 1A Main valve chamber 1B Main valve port 2 Guide member 3 Main valve body 3B Sub-valve chamber 3C Holding member 3D Sub-valve port 3E Communication passage 3F Annular space 3G Throttle passage 3H Enlarged space 3J Bent path 4 Sub-valve body 37 Silencer member 38E Through hole (throttle passage, second communication passage)
39 Squeezing member (first fixing member)
39A through hole (throttling passage, first through hole)
42 Needle valve 60 Fixed member 61 First fixed member 61A Bottom portion 61B Wall portion 61C First through hole (throttling passage)
62 Second fixing member 62A Second through hole (throttling passage)

Claims (12)

a main valve body defining a main valve chamber and a main valve port, a main valve element provided within the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed within the main valve element and movable in an axial direction, wherein the main valve element closes the main valve port, and an opening degree of a sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby providing a small flow rate control range for throttling a flow rate of a fluid in a gap between the needle valve and the sub-valve port,
The main valve body is formed with a communication passage that opens toward the main valve chamber, and an annular space that is continuous around an axis between the communication passage and the sub-valve chamber,
a resin sound-deadening member that allows the fluid to pass through is provided between the communication passage and the sub-valve port ;
a valve member that receives the sound from the main valve chamber and a valve opening that receives the sound from the main valve chamber and a valve port opening that receives the sound from the main valve chamber and a valve ... a main valve body defining a main valve chamber and a main valve port, a main valve element provided within the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed within the main valve element and movable in an axial direction, wherein the main valve element closes the main valve port, and an opening degree of a sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby providing a small flow rate control range for throttling a flow rate of a fluid in a gap between the needle valve and the sub-valve port,
The main valve body is formed with a communication passage that opens toward the main valve chamber, and an annular space that is continuous around an axis between the communication passage and the sub-valve chamber,
a resin sound-deadening member that allows the fluid to pass through is provided between the communication passage and the sub-valve port ;
a throttle passage having a flow passage cross-sectional area smaller than that of the annular space, the throttle passage being provided between the annular space and the sub-valve chamber; a main valve body defining a main valve chamber and a main valve port, a main valve element provided within the main valve chamber for opening and closing the main valve port, and a sub-valve element provided in a sub-valve chamber formed within the main valve element and movable in an axial direction, wherein the main valve element closes the main valve port, and an opening degree of a sub-valve port provided in the main valve element is controlled by a needle valve of the sub-valve element, thereby providing a small flow rate control range for throttling a flow rate of a fluid in a gap between the needle valve and the sub-valve port,
The main valve body is formed with a communication passage that opens toward the main valve chamber, and an annular space that is continuous around an axis between the communication passage and the sub-valve chamber,
a resin sound-deadening member that allows the fluid to pass through is provided between the communication passage and the sub-valve port ;
A fixing member for holding the sound absorbing member is provided within the main valve body,
An electric valve characterized in that the fixed member has a first fixed member provided on the annular space side, and the first fixed member has a first through hole communicating with the annular space. 4. The motor-operated valve according to claim 1, wherein the sound-deadening member is disposed between the annular space and the sub-valve chamber, and deadens noise caused by the passage of the fluid therethrough. 5. The motor-operated valve according to claim 1 , wherein the annular space has a flow passage cross-sectional area larger than a total of flow passage cross-sectional areas of the communication passages. The motor-operated valve according to any one of claims 1 to 5, characterized in that the sub-valve chamber is provided with an expanded space whose volume is larger than that of the annular space. The motor-operated valve according to claim 3 , wherein the first fixing member has a bottom portion that abuts against a bottom surface of the sound deadening member, and a wall portion that faces a side surface of the sound deadening member. The motor-operated valve according to claim 7, characterized in that the first through hole is provided in the bottom portion, the height dimension of the wall portion is formed smaller than the height dimension of the sound-absorbing member, and a side surface of the sound-absorbing member beyond the tip end of the wall portion is exposed. 9. The motor-operated valve according to claim 7 or 8, characterized in that the fixed member has a second fixed member provided on the opposite side of the first fixed member with the sound-absorbing member in between, and the first fixed member and the second fixed member sandwich and hold the sound-absorbing member from both sides in the axial direction. The motor-operated valve according to claim 9 , wherein the second fixing member is provided in contact with substantially the entire surface of one surface of the sound deadening member, and is provided with a second through hole communicating with the sub-valve chamber. The motor-operated valve according to claim 10, characterized in that the radial width dimension of the second fixing member is formed smaller than the radial width dimension of the sound-absorbing member, and the second fixing member is provided in partial contact with one surface of the sound-absorbing member. The motor-operated valve according to any one of claims 9 to 11, characterized in that at least one of the first fixed member and the second fixed member is an elastic member.

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