JP7160369B2 - electric valve - Google Patents

Description

The present invention relates to an electrically operated valve.

An example of a conventional motor-operated valve is disclosed in Patent Document 1. This electrically operated valve has a valve body that opens and closes a valve opening in a valve chamber. The valve body is inserted into the valve body guide hole of the support member. The valve body is vertically movable within the valve body guide hole. A sealing member is arranged between the valve body and the support member. The sealing member separates the valve chamber from the space above the valve body (back pressure chamber) in the valve body guide hole. The motor-operated valve is closed when the lower end of the valve disc contacts the valve seat and the valve opening closes. In the closed state, the valve port and the back pressure chamber are connected through a pressure equalizing passage provided in the valve body. This structure cancels upward fluid pressure and downward fluid pressure applied to the valve body.

Patent No. 6516960

An electrically operated valve having the structure described above can reduce the force required to move the valve body. Therefore, the motor-operated valve can employ a relatively large valve opening. When the valve opening of the electric valve is enlarged, it is necessary to reduce the gap between the valve body and the support member in order to bring the valve body and the valve seat into contact with high accuracy. However, if the gap is made small, it becomes difficult for the fluid in the valve chamber and the fluid in the back pressure chamber to be introduced into the space adjacent to the sealing member. Therefore, the fluid pressure is not appropriately applied to the sealing member, making it difficult for the sealing member to function normally. As a result, in the electric valve, there is a risk that the differential pressure that can seal the fluid between the valve chamber and the back pressure chamber will decrease, or that the torque required to move the valve body will increase.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a motor-operated valve in which a sealing member that separates a valve chamber and a back pressure chamber can function normally while ensuring contact accuracy between a valve element and a valve seat. do.

To achieve the above object, an electrically operated valve according to one aspect of the present invention includes a valve body having a valve chamber and a valve opening, a valve body for opening and closing the valve opening, and a valve body guide into which the valve body is inserted. a support member having a hole; and a back pressure which is a space between the valve opening and the valve body guide hole on the other end side of the valve body in a closed state in which one end of the valve body is in contact with the valve seat of the valve mouth. and an annular sealing member arranged between the valve body and the support member so as to separate the valve chamber and the back pressure chamber, wherein the A valve body has an annular groove for holding the sealing member on its outer peripheral surface, and the sealing member is disposed between the valve body and the support member in a state of being radially compressed, a groove-shaped or hole-shaped valve-chamber-side fluid introduction path connecting the valve chamber and a space adjacent to the valve-chamber side of the sealing member in the annular groove ; and a groove-shaped or hole-shaped back-pressure-chamber-side fluid introduction path connecting a space adjacent to the back-pressure-chamber side of the sealing member in the groove .
In order to achieve the above object, an electrically operated valve according to another aspect of the present invention includes: a valve main body having a valve chamber and a valve opening; a valve body for opening and closing the valve opening; a support member having a body guide hole; and a space between the valve port and the valve body guide hole on the other end side of the valve body in a closed state in which one end of the valve body is in contact with the valve seat of the valve port. a pressure equalizing passage connecting a back pressure chamber; and an annular sealing member arranged between the valve body and the support member so as to partition the valve chamber and the back pressure chamber. The support member has an annular groove for holding the sealing member in the inner peripheral surface of the valve body guide hole, and the sealing member is radially compressed between the valve body and the support member. a groove-shaped or hole-shaped valve-chamber-side fluid introduction passage arranged in a closed state, wherein the support member connects the valve chamber and a space adjacent to the valve-chamber side of the sealing member in the annular groove; and a groove-shaped or hole-shaped back pressure chamber side fluid introduction path connecting the back pressure chamber and a space adjacent to the back pressure chamber side of the sealing member in the annular groove. It is characterized by

In the electrically operated valve according to the present invention, the valve body or the support member has a groove-shaped or hole-shaped valve-chamber-side fluid introduction path that connects the valve chamber and the space adjacent to the valve-chamber side of the sealing member. . With this configuration, the electrically operated valve can introduce the fluid from the valve chamber into the space adjacent to the valve chamber side of the sealing member through the valve chamber side fluid introduction path. Therefore, in the electric valve, the fluid pressure is appropriately applied to the sealing member, and the sealing member can function normally.

In the present invention, the valve body or the support member defines a groove-shaped or hole-shaped back pressure chamber side fluid introduction passage that connects the back pressure chamber and the space adjacent to the back pressure chamber side of the sealing member. It is preferable to have By doing so, the fluid can be introduced from the back pressure chamber into the space adjacent to the back pressure chamber side of the sealing member through the back pressure chamber side fluid introduction path. Therefore, the fluid pressure is appropriately applied to the sealing member, and the sealing member can function normally.

In the present invention, the valve body has one or a plurality of the valve chest side fluid introduction passages, and the total cross-sectional area of the valve chest side fluid introduction passages is the distance between the valve body and the support member. It is preferably larger than the cross-sectional area of the annular gap. In the present invention, the support member has one or more valve chamber side fluid introduction passages, and the total cross-sectional area of the valve chamber side fluid introduction passages is the distance between the valve body and the support member. It is preferably larger than the cross-sectional area of the annular gap. By doing so, more fluid flows into the one or more valve chamber side fluid introduction passages than in the gap between the valve body and the support member, and the space adjacent to the valve chamber side of the sealing member from the valve chamber. fluid can be quickly introduced into the In addition, it is possible to prevent foreign matter from entering the gap between the valve body and the support member.

In the present invention, the valve body has an annular groove for holding the sealing member on its outer peripheral surface, and the sealing member includes an annular seal portion made of a rubber-like elastic material and an annular seal portion formed on the outer peripheral portion of the seal portion. and an annular outer cap portion that is covered and slid on the support member, and the valve chamber side fluid introduction path connects the valve chamber and a space adjacent to the valve chamber side of the seal portion. preferably. By doing so, the fluid in the valve chamber is introduced to the inside of the outer cap portion through the valve chamber side fluid introduction path, and the fluid in the valve chamber is introduced to the outside of the outer cap portion through the gap between the valve element and the support member. be introduced. Thereby, fluid pressure can be appropriately applied to the outer cap portion. Therefore, it is possible to prevent the outer cap portion from being turned over, and allow the outer cap portion to slide appropriately on the support member.

In the present invention, the support member has an annular groove for holding the sealing member on the inner peripheral surface of the valve body guide hole, and the sealing member is an annular seal portion made of a rubber-like elastic material; an annular inner cap portion that covers an inner peripheral portion of the seal portion and slides on the valve body, wherein the valve-chamber-side fluid introduction path is connected to the valve chamber and the valve chamber of the seal portion; It is preferable to connect the space adjacent to the side. By doing so, the fluid in the valve chamber is introduced to the outside of the inner cap portion through the valve chamber side fluid introduction path, and the fluid in the valve chamber is introduced to the inside of the inner cap portion through the gap between the valve body and the support member. be introduced. Thereby, fluid pressure can be appropriately applied to the inner cap portion. Therefore, it is possible to prevent the inner cap portion from being turned over, and allow the inner cap portion to slide appropriately on the valve body.

In the present invention, the sealing member has an annular reinforcing member and a pair of annular packings arranged to sandwich the reinforcing member, and the sealing member is held by the valve body, It is preferable that an outer lip that slides on the support member is provided on the outer peripheral edge of the packing. By doing so, it is possible to appropriately apply fluid pressure to the packing. Therefore, the outer lip can be properly slid on the support member.

In the present invention, the sealing member has an annular reinforcing member and a pair of annular packings arranged to sandwich the reinforcing member, and the sealing member is held by the supporting member, It is preferable that the inner peripheral edge of the packing is provided with an inner lip that slides on the valve body. By doing so, it is possible to appropriately apply fluid pressure to the packing. Therefore, the inner lip can be properly slid on the valve body.

According to the present invention, the gap between the valve body and the support member is made small to ensure contact accuracy between the valve body and the valve seat, and the sealing member that separates the valve chamber and the back pressure chamber can be properly moved. can function.

1 is a cross-sectional view of an electrically operated valve according to one embodiment of the present invention; FIG. FIG. 2 is an enlarged cross-sectional view of the motor-operated valve of FIG. 1; FIG. 2 is a diagram illustrating the configuration of a fluid introduction path of the motor-operated valve of FIG. 1; 2 is an enlarged sectional view of a motor-operated valve of a first modified example of the motor-operated valve of FIG. 1; FIG. FIG. 5 is a diagram illustrating the configuration of a fluid introduction path of the motor-operated valve of FIG. 4; 2 is an enlarged cross-sectional view of a motor-operated valve of a second modification of the motor-operated valve of FIG. 1; FIG. FIG. 7 is a diagram illustrating the configuration of a fluid introduction path of the motor-operated valve of FIG. 6; FIG. 11 is an enlarged cross-sectional view of a motor-operated valve of a third modified example of the motor-operated valve of FIG. 1; FIG. 9 is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 8 ; FIG. 11 is an enlarged cross-sectional view of a motor-operated valve according to a fourth modification of the motor-operated valve of FIG. 1; FIG. 11 is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 10 ;

A configuration of a flow path switching valve according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG.

FIG. 1 is a vertical cross-sectional view (a cross-sectional view along an axis L) of an electrically operated valve according to one embodiment of the present invention. FIG. 1 shows an electrically operated valve in an open state. 2 is an enlarged sectional view of the motor-operated valve of FIG. 1. FIG. FIG. 2 shows the electrically operated valve in the closed state. FIG. 3 is a diagram illustrating a fluid introduction path of the motor-operated valve of FIG. 1. FIG. FIG. 3(a) is a cross-sectional view taken along line IIIA-IIIA in FIG. FIG. 3B is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 2 .

A motor-operated valve 1 according to this embodiment is used as an expansion valve in, for example, a heat pump air conditioning system. The motor-operated valve 1 is a two-way flow type motor-operated valve in which fluid (refrigerant) flows in both directions.

The electrically operated valve 1 includes a valve body 10 , a can 18 , a support member 21 , a bearing member 22 , a valve body 30 , a sealing member 34 and a valve body driving portion 40 .

The valve body 10 has a tubular member 11 , a holder 12 and a valve seat member 13 .

The tubular member 11 has a substantially cylindrical shape. A valve chamber 14 is provided inside the cylindrical member 11 .

The holder 12 has a substantially cylindrical stepped shape with a lower outer diameter larger than an upper outer diameter. The lower part of the holder 12 is fitted into the upper end opening 11a of the tubular member 11 . The tubular member 11 and the holder 12 are welded together. The amount of fitting between the holder 12 and the cylindrical member 11 is set to such an extent that the fitting structure is maintained even after welding.

The valve seat member 13 has a substantially cylindrical shape. The valve seat member 13 is accommodated in the valve chamber 14 . The lower portion of the valve seat member 13 is fitted into the lower end opening 11b of the tubular member 11 . The tubular member 11 and the valve seat member 13 are brazed. The valve seat member 13 has a valve port 13a which is a circular hole. The valve port 13 a opens into the valve chamber 14 . An annular valve seat 13 b is provided on the inner edge of the upper end of the valve seat member 13 . The valve seat 13b is arranged to surround the valve opening 13a.

A first conduit 15 is brazed to the tubular member 11 . The first conduit 15 penetrates the cylindrical member 11 in the lateral direction (direction perpendicular to the axis L) and is connected to the valve chamber 14 . A second conduit 16 is brazed to the valve seat member 13 . The second conduit 16 is connected to the valve port 13a. The insertion length of the first conduit 15 into the cylindrical member 11 should be such that melted wax (fillet) does not flow into the first conduit 15 from the valve chamber 14 side during brazing. is desirable.

The can 18 has a cylindrical shape with a closed upper end. The lower end of the can 18 is welded to the upper portion of the holder 12 .

The support member 21 has a substantially cylindrical shape. The support member 21 is press-fitted inside the holder 12 of the valve body 10 . The support member 21 is arranged to face the valve seat member 13 with a gap in the vertical direction (the direction of the axis L). The support member 21 has a partition wall 21a. The partition wall 21a divides the inner space of the support member 21 vertically. A space above the partition wall 21 a serves as a spring chamber 27 . A space below the partition wall 21 a serves as a valve body guide hole 28 .

The bearing member 22 has a bearing body portion 22a and a bearing extension portion 22b. The bearing body portion 22a has a cylindrical shape. The bearing extension 22b has a cylindrical shape with an outer diameter smaller than that of the bearing body 22a. The bearing extension portion 22b is coaxially connected to the lower end of the bearing body portion 22a. An inner peripheral surface of the bearing member 22 is provided with a female thread 22c. The internal thread 22c is arranged across the bearing main body portion 22a from the bearing extension portion 22b. The bearing member 22 is arranged inside the upper portion of the support member 21 . The bearing member 22 is crimped to the upper portion of the support member 21 .

The valve body 30 opens and closes the valve opening 13a. The valve body 30 has a substantially cylindrical shape. The outer diameter of the valve body 30 is slightly smaller than the diameter of the valve body guide hole 28 of the support member 21 . The valve body 30 is inserted into the valve body guide hole 28 . A space above the valve body 30 in the valve body guide hole 28 serves as a back pressure chamber 29 . The valve body 30 is vertically slidable within the valve body guide hole 28 . The valve body 30 is supported by the support member 21 so as to vertically face the valve seat member 13 . The vertical movement of the valve body 30 is guided by the support member 21 .

The valve body 30 has a cylindrical body 31 and a pressing member 32 . An annular plate-shaped pressing member 32 is arranged on the upper surface 31 a of the cylindrical body 31 . The pressing member 32 forms an annular groove 33 together with a notch step provided on the peripheral edge of the upper surface 31 a of the cylindrical body 31 . The annular groove 33 holds an annular sealing member 34 .

The sealing member 34 is arranged in a radially compressed state between the valve body 30 and the support member 21 . The sealing member 34 closes the space between the valve body 30 and the support member 21 . The sealing member 34 separates the valve chamber 14 and the back pressure chamber 29 .

The sealing member 34 has a seal portion 34a and an outer cap portion 34b. The seal portion 34a is an annular member made of a rubber-like elastic material (a rubber material or a synthetic resin material having rubber-like elasticity). The seal portion 34a is, for example, an O-ring. The outer cap portion 34b is an annular band-shaped member made of synthetic resin such as polytetrafluoroethylene (PTFE), which is less elastically deformable than the seal portion 34a. The outer cap portion 34b covers the outer peripheral portion of the seal portion 34a. The outer peripheral surface of the outer cap portion 34 b contacts the inner peripheral surface of the valve body guide hole 28 . When the valve body 30 moves vertically, the outer peripheral surface of the outer cap portion 34b slides on the inner peripheral surface of the valve body guide hole 28. As shown in FIG. The material of the outer cap portion 34b is selected in consideration of slidability, foreign matter resistance, and wear resistance under the environment of the refrigerant state (high temperature gas, low temperature liquid, etc.) flowing inside. In addition, the sealing member 34 may be configured by, for example, only the seal portion 34a.

Between the valve body 30 and the support member 21, more specifically, between the outer peripheral surface of the cylindrical body 31 and the inner peripheral surface of the valve body guide hole 28, an annular gap C1 is provided. An annular gap C2 is provided between the outer peripheral surface of the pressing member 32 and the inner peripheral surface of the valve body guide hole 28 . In this embodiment, the gap C1 and the gap C2 have the same size. The gap C1 is located closer to the valve chamber 14 than the sealing member 34 is. The gap C2 is located closer to the back pressure chamber 29 than the sealing member 34 is.

A valve chamber side fluid introduction passage 35 having a groove shape is provided on the outer peripheral surface of the cylindrical body 31 . The valve chamber side fluid introduction passage 35 extends linearly in the vertical direction from the vicinity of the lower end 31 b of the cylindrical body 31 to the annular groove 33 . In this embodiment, four valve chamber side fluid introduction passages 35 are provided and arranged at equal intervals in the circumferential direction. The number of the valve chest side fluid introducing passages 35 may be one or plural. The valve chamber side fluid introduction path 35 connects the valve chamber 14 and a space (valve chamber side space 33 a ) adjacent to the valve chamber 14 side of the seal portion 34 a of the sealing member 34 in the annular groove 33 . . The valve chest side fluid introduction path 35 introduces the fluid in the valve chest 14 into the valve chest side space 33a.

A back pressure chamber side fluid introduction passage 36 having a groove shape is provided on the outer peripheral surface of the pressing member 32 . The back pressure chamber side fluid introduction passage 36 extends linearly in the direction of the axis L from the upper surface of the pressing member 32 to the annular groove 33 . In this embodiment, four back pressure chamber side fluid introduction passages 36 are provided and arranged at equal intervals in the circumferential direction. The number of back pressure chamber side fluid introduction paths 36 may be one or plural. The back pressure chamber side fluid introduction path 36 connects the back pressure chamber 29 and a space adjacent to the back pressure chamber 29 side of the seal portion 34 a of the sealing member 34 in the annular groove 33 (back pressure chamber side space 33 b ). Connected. The back pressure chamber side fluid introduction path 36 introduces the fluid inside the back pressure chamber 29 into the back pressure chamber side space 33b. The clearance C2 between the outer peripheral surface of the pressing member 32 and the inner peripheral surface of the valve body guide hole 28 may be increased to omit the back pressure chamber side fluid introduction passage 36 .

The valve-chest-side fluid introduction path 35 is a groove with a semicircular cross-sectional shape. The valve chamber side fluid introduction path 35 may be a V-shaped groove, a rectangular groove, or the like having a cross-sectional shape. Alternatively, the valve chamber side fluid introduction passage 35 may have a hole shape passing through the valve body 30 as long as it connects the valve chamber 14 and the valve chamber side space 33a. The back pressure chamber side fluid introduction path 36 is also a groove with a semicircular cross section. The back-pressure-chamber-side fluid introduction path 36 may also have a cross-sectional shape of a V-shaped groove, a rectangular groove, or the like, or may be of a hole shape.

The total cross-sectional area S2, which is the total value of the cross-sectional areas (cross-sectional areas orthogonal to the axis L) of the valve chamber side fluid introduction passages 35, is equal to the annular gap C1 between the cylindrical body 31 of the valve body 30 and the support member 21. is preferably larger than the cross-sectional area S1 (cross-sectional area perpendicular to the axis L). By doing so, more fluid flows in the valve chamber side fluid introduction path 35 than in the gap C1, and the fluid in the valve chamber 14 can be quickly introduced into the valve chamber side space 33a. In addition, it is possible to prevent foreign matter from entering the gap C1. The total cross-sectional area of the back pressure chamber side fluid introduction passage 36 is also preferably larger than the cross-sectional area of the annular gap C2 between the pressing member 32 of the valve body 30 and the support member 21 .

The valve body drive unit 40 moves the valve body 30 in the up-down direction to bring the valve body 30 into contact with and separate from the valve seat 13b of the valve seat member 13 .

The valve body driving portion 40 has a stator 42 , a rotor 43 , a rotor shaft 44 , a connecting member 45 and a planetary gear mechanism 50 . The stator 42 is arranged outside the can 18 . The rotor 43 is rotatably arranged inside the can 18 . The rotor 43 is connected to the rotor shaft 44 via a disk-shaped connecting member 45 . The stator 42 and rotor 43 constitute an electric motor. The planetary gear mechanism 50 slows down the rotation of the rotor 43 .

The planetary gear mechanism 50 is arranged inside the rotor 43 . The planetary gear mechanism 50 has a gear case 51 , a sun gear 52 , a fixed ring gear 53 , a planetary gear 54 , a carrier 55 , an output gear 56 and an output shaft 57 . Gear case 51 has a cylindrical shape and is fixed to the upper portion of support member 21 . The sun gear 52 is integrated with the connecting member 45 . The rotor shaft 44 is inserted through the inside of the sun gear 52 . A fixed ring gear 53 is an internal gear and is fixed to the upper end of the gear case 51 . A plurality of planetary gears 54 are provided so as to surround the sun gear 52 . Planetary gear 54 meshes with sun gear 52 and fixed ring gear 53 . Carrier 55 rotatably supports planetary gear 54 . The output gear 56 is an internal gear having a cylindrical shape with a bottom. The output gear 56 meshes with the planetary gear 54 . The output shaft 57 has a substantially cylindrical shape. The output shaft 57 is arranged inside the bearing body portion 22a. The output shaft 57 is rotatably supported around the axis L by the bearing body portion 22a. The upper portion of the output shaft 57 is press-fitted into the through-hole at the bottom of the output gear 56 . The output shaft 57 rotates together with the output gear 56 . The output shaft 57 has a slit 57a extending upward from the bottom surface.

Further, the valve body driving portion 40 has a spring bearing body 61 , a valve opening spring 62 , a thrust force transmission member 63 , a rotary elevating shaft 64 , a ball 67 and a ball bearing seat 68 .

The spring receiving body 61 has a cylindrical portion 61a, an annular upper hook portion 61b, and an annular lower hook portion 61c. The inner diameter of cylindrical portion 61a is slightly larger than the outer diameter of bearing extension 22b. A bearing extension 22b is inserted into the cylindrical portion 61a. The bearing extension 22b guides the movement of the spring bearing 61 in the vertical direction. The upper hook portion 61b protrudes radially outward from the upper end of the cylindrical portion 61a. The lower hook portion 61c protrudes radially inward from the lower end of the cylindrical portion 61a. The spring receiver 61 is housed in the spring chamber 27 .

The valve opening spring 62 is a spiral coil spring. The valve-opening spring 62 is arranged in a compressed state between the partition wall 21 a of the support member 21 and the upper hook portion 61 b of the spring bearing body 61 in the spring chamber 27 . The valve-opening spring 62 applies a force that pushes the spring bearing 61 upward (in the valve-opening direction).

The thrust transmission member 63 has a substantially cylindrical shape. The thrust transmission member 63 has an upper portion 63a, a central portion 63b, and a lower portion 63c that are successively arranged from top to bottom. The outer diameter of the upper portion 63a is larger than the outer diameter of the central portion 63b. The outer diameter of the central portion 63b is larger than the outer diameter of the lower portion 63c. The center portion 63b is inserted inside the through hole 21b provided in the partition wall 21a of the support member 21 and the lower hook portion 61c. It is desirable that the gap between the central portion 63b and the through hole 21b is minute. The lower end of the upper portion 63a is in contact with the lower hook portion 61c. The lower portion 63 c passes through the inner side of the pressing member 32 of the valve body 30 and is press-fitted into the hole 31 c of the upper surface 31 a of the cylindrical body 31 . A pressing member 32 is held between the lower end of the central portion 63 b and the upper surface 31 a of the cylindrical body 31 .

The thrust transmission member 63 has a vertical passage 63d and a horizontal passage 63e. The vertical passage 63d extends vertically. The horizontal passage 63e extends laterally from the vertical passage 63d in the central portion 63b. A pressure equalizing passage 39 is composed of the inner space 31d of the cylindrical body 31 of the valve body 30, the vertical passage 63d and the horizontal passage 63e. The pressure equalizing passage 39 connects the valve port 13a and the back pressure chamber 29 in the closed state.

The rotary elevating shaft 64 is made of metal such as stainless steel, and has a cylindrical portion 65 and a flat plate portion 66 . A male screw 65c is provided on the outer peripheral surface of the cylindrical portion 65 . The male thread 65 c is screwed into the female thread 22 c of the bearing member 22 . The flat plate portion 66 is connected to the upper surface of the cylindrical portion 65 . The thickness of the flat plate portion 66 is slightly smaller than the width of the slit 57 a of the output shaft 57 . The flat plate portion 66 is inserted into the slit 57a so as to be vertically movable. The rotary elevating shaft 64 is rotated with the rotation of the output shaft 57 and moved vertically by a screw feeding action. The rotary elevating shaft 64 is connected to the valve body 30 via a ball 67 , a ball receiving seat 68 and a thrust force transmission member 63 . It is desirable that the threaded portion such as the male thread 65c, the ball 67, and the ball receiving seat 68 have high hardness. In this embodiment, these members are heat-treated to increase their hardness.

In this embodiment, the tubular member 11, the valve seat member 13 (valve port 13a, valve seat 13b), the support member 21, the valve body guide hole 28, the bearing member 22, the valve body 30, the rotor shaft 44, the output shaft 57, The axial center of each of the spring receiving body 61, the thrust transmission member 63, and the rotary elevating shaft 64 coincides with the axis line L. As shown in FIG.

Next, an example of the operation of the motor operated valve 1 according to this embodiment will be described.

The motor-operated valve 1 generates a rotational force in the rotor 43 by applying an electric current to the stator 42 . The rotational force of the rotor 43 is decelerated by the planetary gear mechanism 50 and transmitted from the output shaft 57 to the rotary elevating shaft 64 . The rotary elevating shaft 64 moves up and down according to the direction of rotation by the screw feeding action with the bearing member 22 .

When the rotary elevating shaft 64 moves downward (in the valve closing direction), the thrust transmission member 63 is pushed downward via the ball 67 and the ball receiving seat 68 . The valve body 30 moves downward together with the thrust transmission member 63, and the lower end 31b of the cylindrical body 31 of the valve body 30 contacts the valve seat 13b to close the valve port 13a (valve closed state). At this time, the valve opening spring 62 is compressed. In the closed state, the valve port 13 a and the back pressure chamber 29 are connected through the pressure equalizing passage 39 . Therefore, the upward fluid pressure and the downward fluid pressure applied to the valve body 30 are cancelled.

In order to effectively cancel the fluid pressure, the outer diameter D1 of the sealing member 34 and the diameter D2 of the valve seat 13b (specifically, the diameter of the contact portion between the valve body 30 and the valve seat 13b) are made the same. is desirable. However, these diameters may have dimensional differences in consideration of the force of the valve opening spring 62 . In the case of this embodiment, the valve opening spring 62 is composed of a compression coil spring that exerts a certain amount of pressure in the valve opening direction at any position from the valve closed state to the fully open state. At , a stronger pressing force is generated than at the valve open position. When the valve is closed, the rotary elevating shaft 64 must move the valve body 30 in the opposite direction (valve closing direction) to the pressing force of the valve opening spring 62 in the valve opening direction. Therefore, the valve closing force can be increased by adopting a compression coil spring with a small pressing force as the valve opening spring 62 without changing the outer diameter D1 and the diameter D2. For applications in which the fluid pressure on the side of the second conduit 16 increases when the valve is closed, the outer diameter D1 of the sealing member 34 is made larger than the diameter D2 of the valve seat 13b (D1>D2). As a result, the force (valve closing force) that pushes the valve body in the valve closing direction can be increased. Further, if a compression coil spring with a small spring constant is used as the valve opening spring 62, it is possible to reduce the influence of changes in the pressing force due to the position of the valve body in the vertical direction (such as changes in the load applied to the rotating vertical shaft 64). can. In this embodiment, the pressing force of the spring is generated in the valve opening direction, but in a configuration in which the spring pressing force is generated in the valve closing direction, the pressing force in the valve opening direction can be reduced by setting D2>D1. can be increased.

When the rotary elevating shaft 64 moves upward in the valve closed state, the valve opening spring 62 is restored and the spring receiving body 61 moves upward. The upper portion 63a of the thrust transmission member 63 is caught by the lower hook portion 61c of the spring receiving body 61, and the thrust transmission member 63 is pulled upward. The valve body 30 moves upward together with the thrust transmission member 63, the lower end 31b of the cylindrical body 31 of the valve body 30 moves away from the valve seat 13b, and the valve port 13a opens (valve open state).

The valve chamber 14 and the valve chamber side space 33 a of the annular groove 33 of the valve body 30 are connected by the valve chamber side fluid introduction path 35 . Therefore, the fluid in the valve chamber 14 is introduced into the valve chamber side space 33a, and the pressure of the fluid is applied to the sealing member 34 appropriately. The back pressure chamber 29 and the back pressure chamber side space 33 b of the annular groove 33 of the valve body 30 are connected by the back pressure chamber side fluid introduction path 36 . Therefore, the fluid in the back pressure chamber 29 is introduced into the back pressure chamber side space 33b, and the pressure of the fluid is appropriately applied to the sealing member . Thereby, the sealing member 34 functions normally.

As described above, in the electrically operated valve 1 according to the present embodiment, the valve body 30 has a groove-shaped valve chamber side fluid flow that connects the valve chamber 14 and the valve chamber side space 33a adjacent to the valve chamber 14 side of the sealing member 34. It has an introduction path 35 . Further, the valve body 30 has a groove-shaped back pressure chamber side fluid introduction passage 36 that connects the back pressure chamber 29 and the back pressure chamber side space 33b adjacent to the back pressure chamber 29 side of the sealing member 34. there is As a result, the motor-operated valve 1 can introduce fluid from the valve chamber 14 into the valve chamber side space 33a through the valve chamber side fluid introduction passage 35, A fluid can be introduced from the pressure chamber 29 into the back pressure chamber side space 33b. Therefore, in the electric valve 1, the fluid pressure is appropriately applied to the sealing member 34, the gaps C1 and C2 between the valve body 30 and the support member 21 are reduced, and the contact accuracy between the valve body 30 and the valve seat 13b is improved. It is possible to allow the sealing member 34 to function normally while ensuring this.

In addition, the motor-operated valve 1 has a plurality of valve-chamber-side fluid introduction passages 35 . The total cross-sectional area S2 of the valve chamber side fluid introduction passage 35 is larger than the cross-sectional area S1 of the annular gap C1 between the valve body 30 and the support member 21 . By doing so, more fluid flows through the plurality of valve chamber side fluid introduction paths 35 than in the gap C1, and the fluid flows from the valve chamber 14 to the valve chamber side space 33a adjacent to the sealing member 34 on the valve chamber 14 side. can be introduced quickly. In addition, it is possible to prevent foreign matter from entering the gap C1.

Further, the valve body 30 has an annular groove 33 for holding a sealing member 34 on its outer peripheral surface. The sealing member 34 has an annular seal portion 34a made of a rubber-like elastic material, and an annular outer cap portion 34b that covers the outer periphery of the seal portion 34a and slides on the support member 21. . The valve chamber side fluid introduction path 35 connects the valve chamber 14 and the valve chamber side space 33a adjacent to the valve chamber 14 side of the seal portion 34a, and the back pressure chamber side fluid introduction path 36 connects the back pressure chamber 29 and the back pressure chamber side space 33b adjacent to the back pressure chamber 29 side of the seal portion 34a. By doing so, the fluid in the valve chamber 14 is introduced into the outer cap portion 34b through the valve chamber side fluid introduction passage 35, and the fluid in the valve chamber 14 is introduced to the outside of the outer cap portion 34b through the gap C1. be done. The fluid in the back pressure chamber 29 is introduced to the inside of the outer cap portion 34b through the back pressure chamber side fluid introduction passage 36, and the fluid in the back pressure chamber 29 is introduced to the outside of the outer cap portion 34b through the gap C2. As a result, fluid pressure can be appropriately applied to the outer cap portion 34b. Therefore, the outer cap portion 34b can be prevented from being turned over, and the outer cap portion 34b can be slid properly on the support member 21. As shown in FIG.

Next, a modification of the motor-operated valve 1 according to the present embodiment described above will be described. In the following description, the same (including substantially the same) configurations as those of the electrically operated valve 1 are denoted by the same reference numerals, and descriptions thereof are omitted.

(First modification)
A motor-operated valve 1A, which is a first modification of the above-described motor-operated valve 1, is shown in FIGS.

4 is an enlarged cross-sectional view of a motor-operated valve of a first modification of the motor-operated valve of FIG. 1. FIG. 5 is a diagram for explaining the configuration of the fluid introduction path of the motor-operated valve of FIG. 4. FIG. FIG. 5(a) is a cross-sectional view taken along line VA--VA in FIG. FIG. 5B is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 4 .

The electrically operated valve 1A has a plurality of hole-shaped valve chamber side fluid introduction passages 35A and a plurality of hole-shaped back pressure chamber side fluid introduction passages 36A. The motor-operated valve 1A is substantially the same as the motor-operated valve 1 described above except for the valve body 30A (cylindrical body 31A and pressing member 32A) provided with a valve chamber side fluid introduction passage 35A and a back pressure chamber side fluid introduction passage 36A. is identical to

The valve chest side fluid introduction path 35</b>A connects the valve chest 14 and the valve chest side space 33 a of the annular groove 33 . The valve chest side fluid introduction path 35A introduces the fluid inside the valve chest 14 into the valve chest side space 33a. The back pressure chamber side fluid introduction path 36</b>A connects the back pressure chamber 29 and the back pressure chamber side space 33 b of the annular groove 33 . The back pressure chamber side fluid introduction path 36A introduces the fluid inside the back pressure chamber 29 into the back pressure chamber side space 33b.

(Second modification)
A motor-operated valve 1B, which is a second modification of the above-described motor-operated valve 1, is shown in FIGS.

6 is an enlarged sectional view of a motor-operated valve of a second modification of the motor-operated valve of FIG. 1. FIG. FIG. 7 is a diagram for explaining the configuration of the fluid introduction path of the motor-operated valve of FIG. 6. FIG. FIG. 7(a) is a cross-sectional view taken along line VIIA--VIIA in FIG. FIG. 7B is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 6 .

The electrically operated valve 1B is provided with an annular groove 23 in the inner peripheral surface of the valve body guide hole 28 of the support member 21B. The annular groove 23 holds an annular sealing member 24 . The sealing member 24 is arranged in a radially compressed state between the valve body 30B and the support member 21B. The sealing member 24 closes the space between the valve body 30B and the support member 21B. The sealing member 24 separates the valve chamber 14 and the back pressure chamber 29 . The electric valve 1B is substantially the same as the electric valve 1 described above except for the support member 21B, the sealing member 24, and the valve body 30B.

The sealing member 24 has a seal portion 24a and an inner cap portion 24b. The seal portion 24a is an annular member made of a rubber-like elastic material. The seal portion 24a is, for example, an O-ring. The inner cap portion 24b is an annular band-shaped member made of synthetic resin such as PTFE. The inner cap portion 24b covers the inner peripheral portion of the seal portion 24a. The inner peripheral surface of the inner cap portion 24b is in contact with the outer peripheral surface of the valve body 30B. When the valve body 30B moves vertically, the inner peripheral surface of the inner cap portion 24b slides on the outer peripheral surface of the valve body 30B. In addition, the sealing member 24 may be configured by, for example, only the seal portion 24a.

The support member 21B is provided with a plurality of valve chamber side fluid introduction paths 25B having a hole shape. The valve chamber side fluid introduction path 25B extends linearly in the vertical direction from the lower end of the support member 21B to the annular groove 23 . The valve-chamber-side fluid introduction passage 25B is formed by fitting a cylindrical member 21c having a groove on its outer peripheral surface inside the lower portion of the support member 21B.

The valve body 30B has a cylindrical body 31B. A lower portion 63c of the thrust transmission member 63 is press-fitted into the hole 31c of the upper surface 31a of the cylindrical body 31B. The lower end of the central portion 63b of the thrust transmission member 63 is in contact with the upper surface 31a.

The valve chamber side fluid introduction path 25B connects the valve chamber 14 and a space (valve chamber side space 23a) adjacent to the valve chamber 14 side of the seal portion 24a of the sealing member 24 in the annular groove 23. . The valve chest side fluid introduction path 25B introduces the fluid in the valve chest 14 into the valve chest side space 23a.

(Third modification)
A motor-operated valve 1C, which is a third modification of the above-described motor-operated valve 1, is shown in FIGS.

8 is an enlarged cross-sectional view of a motor-operated valve according to a third modification of the motor-operated valve of FIG. 1. FIG. FIG. 9 is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 8 .

The electrically operated valve 1C has a relatively large gap between the upper portion of the valve body 30C and the valve body guide hole 28. As shown in FIG. An annular sealing member 37 is provided so as to protrude from the outer peripheral surface of the valve body 30C. The sealing member 37 is arranged between the valve body 30</b>C and the support member 21 . The electric valve 1C is substantially the same as the electric valve 1 described above except for the sealing member 37 and the valve body 30C.

The sealing member 37 is held between the cylindrical body 31C of the valve body 30C and the pressing member 32C. The sealing member 37 has an annular reinforcing member 37a and annular packings 37b, 37b. The reinforcing member 37a is made of, for example, a resin material such as polyphenylene sulfide (PPS) or a metal material such as brass. The packing 37b is made of, for example, a resin material such as PTFE. The packings 37b, 37b form a pair. The packings 37b, 37b are arranged so as to vertically sandwich the reinforcing member 37a. An annular outer lip 37c is provided on the outer peripheral edge of the packing 37b. The packing 37b has a substantially L-shaped cross section. The outer lip 37 c slides on the inner peripheral surface of the valve body guide hole 28 .

The cylindrical body 31C of the valve body 30C is provided with a plurality of groove-shaped valve chamber side fluid introduction passages 35C on its outer peripheral surface. The valve chamber side fluid introduction path 35C connects the valve chamber 14 and a space (valve chamber side space 77) adjacent to the sealing member 37 on the valve chamber 14 side. The valve chest side fluid introduction path 35</b>C introduces the fluid inside the valve chest 14 to the valve chest side space 77 .

(Fourth modification)
A motor-operated valve 1D, which is a fourth modification of the above-described motor-operated valve 1, is shown in FIGS. 10 and 11. FIG.

10 is an enlarged cross-sectional view of a motor-operated valve according to a fourth modification of the motor-operated valve of FIG. 1. FIG. FIG. 11 is a cross-sectional view enlarging the inside of the dashed-dotted line frame in FIG. 10 .

A relatively large gap is provided between the valve body 30D and the valve body guide hole 28 in the electric valve 1D. The inner diameter near the lower end of the valve body guide hole 28 is slightly larger than the outer diameter of the valve body 30D. An annular sealing member 38 is provided so as to protrude from the outer peripheral surface of the support member 21D. The sealing member 38 is arranged between the valve body 30D and the support member 21D. The electric valve 1D is substantially the same as the electric valve 1 described above except for the support member 21D, the sealing member 38, and the valve body 30D.

The sealing member 38 is held by the support member 21D. The sealing member 38 has an annular reinforcing member 38a and annular packings 38b, 38b. The reinforcing member 38a is made of, for example, a resin material such as PPS or a metal material such as brass. The packing 38b is made of, for example, a resin material such as PTFE. The packings 38b, 38b form a pair. The packings 38b, 38b are arranged so as to vertically sandwich the reinforcing member 38a. An annular inner lip 38c is provided on the inner peripheral edge of the packing 38b. The packing 38b has a substantially L-shaped cross section. The inner lip 38c slides on the inner peripheral surface of the valve body 30D.

The valve body 30D has a cylindrical body 31D. A lower portion 63c of the thrust transmission member 63 is press-fitted into the hole 31c of the upper surface 31a of the cylindrical body 31D. The lower end of the central portion 63b of the thrust transmission member 63 is in contact with the upper surface 31a.

The support member 21D is provided with a valve chamber side fluid introduction passage 25D having a hole shape. The valve chest side fluid introduction path 25D penetrates the support member 21D in the lateral direction.

The valve chamber side fluid introduction path 25D connects the valve chamber 14 and a space (valve chamber side space 78) adjacent to the sealing member 38 on the valve chamber 14 side. The valve chest side fluid introduction path 25</b>D introduces the fluid inside the valve chest 14 to the valve chest side space 78 .

The electrically operated valves 1A to 1D of the first to fourth modified examples have the same effects as the electrically operated valve 1 described above.

Although embodiments of the present invention have been described above, the present invention is not limited to these examples. A person skilled in the art may add, delete, or change the design of the above-described embodiments as appropriate, or combine the features of the embodiments as appropriate, as long as they do not conflict with the spirit of the present invention. included in the range of

DESCRIPTION OF SYMBOLS 1... Electric valve, 10... Valve main body, 11... Cylindrical member, 11a... Upper end opening, 11b... Lower end opening, 12... Holder, 13... Valve seat member, 13a... Valve opening, 13b... Valve seat, 14... Valve chamber , 15 First conduit 16 Second conduit 18 Can 21 Support member 21a Partition wall 21b Through hole 22 Bearing member 22a Bearing body 22b Bearing extension 22c Female screw 27 Spring chamber 28 Valve body guide hole 29 Back pressure chamber 30 Valve body 31 Cylindrical body 31 a Top surface 31 b Bottom end 31 c Hole 31 d Inner space 32 Presser Members 33 Annular groove 33a Valve chamber side space 33b Back pressure chamber side space 34 Sealing member 34a Seal portion 34b Outer cap portion 35 Valve chamber side fluid introduction path 36 Back pressure chamber side fluid introduction path 39 Pressure equalizing passage 40 Valve body driving portion 42 Stator 43 Rotor 44 Rotor shaft 45 Connecting member 50 Planetary gear mechanism 51 Gear case 52 ...Sun gear 53...Fixed ring gear 54...Planetary gear 55...Carrier 56...Output gear 57...Output shaft 57a...Slit 61...Spring receiving body 61a...Cylindrical part 61b...Upper hook part 61c Lower hook 62 Valve opening spring 63 Thrust transmission member 63a Upper part 63b Central part 63c Lower part 63d Vertical passage 63e Horizontal passage 64 Rotating lifting shaft 65 Cylindrical portion 65c Male screw 66 Flat plate portion 67 Ball 68 Ball receiving seat C1 Gap S1 Cross-sectional area S2 Total cross-sectional area L Axis (first modification)
1A...Motor operated valve 30A...Valve element 31A...Cylindrical body 32A...Pressure member 35A...Valve chamber side fluid introduction path 36A...Back pressure chamber side fluid introduction path (second modification)
1B...Motor operated valve 21B...Supporting member 21c...Cylindrical member 23...Annular groove 23a...Valve chamber side space 24...Sealing member 24a...Seal portion 24b...Inner cap portion 25B...Valve chamber side fluid Introductory path 30B...valve element 31B...cylindrical body (third modification)
1C... motor operated valve 30C...valve element 31C...cylindrical body 32C...pressing member 35C...valve chamber side fluid introduction path 37...sealing member 37a...reinforcing member 37b...packing 37c...outer lip 77 …Valve Chamber Side Space (Fourth Modification)
1D... Electric valve 21D... Supporting member 25D... Valve chamber side fluid introduction passage 30D... Valve body Cylindrical body 31D, 38... Sealing member 38a... Reinforcing member 38b... Packing 38c... Inner lip 78... Valve chamber side space

Claims (6)

a valve body having a valve chamber and a valve port; a valve body for opening and closing the valve port; a support member having a valve body guide hole into which the valve body is inserted; a pressure equalizing passage that connects the valve opening and a back pressure chamber that is a space on the other end side of the valve disc in the valve disc guide hole in a closed state in which the valve is in contact with the valve chamber and the back pressure chamber; an annular sealing member disposed between the valve body and the support member so as to partition the
the valve body has an annular groove on its outer peripheral surface for holding the sealing member;
wherein the sealing member is arranged in a radially compressed state between the valve body and the support member;
The valve element includes a groove-shaped or hole-shaped valve-chamber-side fluid introduction passage connecting the valve chamber and a space adjacent to the valve chamber side of the sealing member in the annular groove, and the back pressure chamber. a groove-shaped or hole-shaped back-pressure-chamber-side fluid introduction path that connects a space adjacent to the back-pressure-chamber side of the sealing member in the annular groove. . a valve body having a valve chamber and a valve port; a valve body for opening and closing the valve port; a support member having a valve body guide hole into which the valve body is inserted; a pressure equalizing passage that connects the valve opening and a back pressure chamber that is a space on the other end side of the valve disc in the valve disc guide hole in a closed state in which the valve is in contact with the valve chamber and the back pressure chamber; an annular sealing member disposed between the valve body and the support member so as to partition the
The support member has an annular groove for holding the sealing member on the inner peripheral surface of the valve body guide hole,
wherein the sealing member is arranged in a radially compressed state between the valve body and the support member;
The support member includes a groove-shaped or hole-shaped valve-chamber-side fluid introduction passage connecting the valve chamber and a space adjacent to the valve chamber side of the sealing member in the annular groove, and the back pressure chamber. a groove-shaped or hole-shaped back-pressure-chamber-side fluid introduction path that connects a space adjacent to the back-pressure-chamber side of the sealing member in the annular groove. . the valve body has one or more valve chest side fluid introduction passages,
2. The motor-operated valve according to claim 1 , wherein the total cross-sectional area of said valve chamber side fluid introduction path is larger than the cross-sectional area of an annular gap between said valve body and said support member. The support member has one or a plurality of the valve chest side fluid introduction paths,
3. The motor-operated valve according to claim 2, wherein a total cross-sectional area of said valve chest side fluid introduction passage is larger than a cross-sectional area of an annular gap between said valve body and said support member. The sealing member has an annular seal portion made of a rubber-like elastic material, and an annular outer cap portion that covers an outer peripheral portion of the seal portion and slides on the support member,
2. The motor-operated valve according to claim 1 , wherein the valve chamber side fluid introduction path connects the valve chamber and a space adjacent to the valve chamber side of the seal portion. The sealing member has an annular seal portion made of a rubber-like elastic material, and an annular inner cap portion that covers an inner peripheral portion of the seal portion and slides on the valve body,
3. The motor-operated valve according to claim 2 , wherein the valve chamber side fluid introduction path connects the valve chamber and a space adjacent to the valve chamber side of the seal portion.

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