Electric valve

Abstract

To provide a motor-operated valve that prevents abrasion of a seal material.SOLUTION: A motor-operated valve 10 includes: a valve seat 24A having a first opening 24A1; a drive shaft 22 extending in a direction orthogonal to the valve seat 24A, and rotating around an axis center offset from the first opening 24A1; a valve body 24D having a seal material 50 and disposed in the drive shaft 22, the valve body 24D opening and closing the first opening 24A1 via the seal material 50 by making rotary motion along the valve seat 24A with the rotation of the drive shaft 22; a spring member 26 for energizing the valve body 24D toward the valve seat 24A; and a conversion mechanism 60 for converting at least a rotary motion of the valve body 24D from a state in which the first opening 24A1 is closed by the seal material 50 to a state in which it is opened into a linear motion of the valve body 24D to a side where the seal material 50 is separated from the valve seat 24A.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to motorized valves. [Background technology]

[0002] Conventionally, there is known a needle valve-type motor-operated valve (hereinafter referred to as a motor-operated needle valve) that adjusts flow rate by moving a valve element up and down using a feed screw mechanism, as in Patent Document 1. The motor-operated needle valve comprises a valve body, a cylindrical can attached to the valve body, a rotor provided inside the can, and a stator disposed outside the can that rotates the rotor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-219059 Summary of the Invention [Problem to be solved by the invention]

[0004] In electric valves that close an opening by rotating a valve body having a sealing material along the opening surface of the housing, conventional electric valves constantly press the sealing material against the opening surface using a biasing part, which causes the sealing material to wear.

[0005] The present disclosure provides an electric valve in which wear of the sealing material of the valve body caused by opening and closing of the opening is suppressed compared to a configuration in which the sealing material of the valve body is constantly pressed against the surface forming the opening. [Means for solving the problem]

[0006] The motor-operated valve of the first aspect comprises a housing having an opening, a shaft extending in a direction perpendicular to the forming surface of the opening and rotating around an axial center offset from the opening, a valve body having a sealing material and attached to the shaft body, which opens and closes the opening with the sealing material by rotating along the forming surface as the shaft body rotates, a biasing section which biases the valve body toward the forming surface, and a conversion mechanism which converts at least the rotational movement of the valve body from a state in which the sealing material closes the opening to a state in which the sealing material opens the opening into linear movement of the valve body in a direction in which the sealing material moves away from the forming surface.

[0007] In the motor-operated valve according to the first aspect, when the valve disc rotates from a closed state to an open state, the conversion mechanism converts the rotational movement of the valve disc into linear movement, causing the seal material to move away from the opening surface. This reduces wear on the seal material compared to a configuration in which the seal material of the valve disc is constantly pressed against the opening surface.

[0008] The electric valve of the second aspect is the electric valve of the first aspect, wherein the conversion mechanism is arranged on the housing and has a convex portion that protrudes away from the opening formation surface, and a plate portion that is arranged on the side of the valve body opposite the convex portion and has an inclined surface that is inclined relative to the opening formation surface, and the convex portion moves along the inclined surface as the shaft body rotates.

[0009] In the motor-operated valve according to the second aspect, the biasing force of the biasing part causes the convex part on the housing to come into contact with the plate part on the valve body side. When the inclined surface moves along the convex part as the valve body rotates, the rotational motion of the valve body is converted into linear motion. In this motor-operated valve, the plate part has an inclined surface with a complex shape, so the direction of motion of the valve body can be changed with a simpler configuration than a configuration in which an inclined surface is arranged on the housing.

[0010] A third aspect of the motor-operated valve is the motor-operated valve according to the second aspect, wherein the convex portion and the inclined surface of the plate portion are both positioned outward from the valve body when viewed in a direction along the axis center.

[0011] In the electric valve of the third aspect, the sealing material moves away from the forming surface with a smaller load than in a configuration in which the convex portion and the inclined surface of the plate portion are arranged between the axial center of the shaft body and the outer edge of the valve body.

[0012] The electric valve of the fourth aspect is an electric valve of either the second or third aspect, in which the plate portion has a flat base surface that continues from the inclined surface in the direction opposite to the rotation direction of the shaft body.

[0013] In the electric valve of the fourth aspect, the sealing material of the valve body is maintained at a distance from the opening formation surface while the base surface passes through the convex portion, so the power required to resist the biasing force of the biasing portion is reduced compared to a configuration in which the plate portion has only an inclined surface.

[0014] The electric valve of the fifth aspect is the electric valve of the fourth aspect, wherein the plate portion is formed adjacent to the base surface in a direction away from the opening formation surface and in the opposite direction to the rotation direction of the shaft body, and has a reference surface along which the convex portion moves when the sealing material changes from a state in which it opens the opening to a state in which it closes it.

[0015] In the motor-operated valve according to the fifth aspect, when the contact surface of the convex portion of the plate portion moves from the base surface to the reference surface as the shaft rotates, the sealing material comes into contact with the surface on which the opening is formed. Furthermore, when the reference surface moves along the convex portion as the shaft rotates, the sealing material changes from a state in which it opens the opening to a state in which it closes it. As a result, in this motor-operated valve, cracking or chipping of the sealing material due to the edge of the opening is suppressed compared to a configuration in which the opening is closed when the contact surface of the convex portion moves from the base surface to the reference surface while the sealing material is overlapping the opening.

[0016] A sixth aspect of the motor-operated valve is the motor-operated valve according to any one of the first to fifth aspects, wherein the conversion mechanisms are arranged in pairs symmetrically with respect to the axial center of the shaft body.

[0017] In the electric valve of the sixth aspect, compared to when there is only one conversion mechanism, the tilt that occurs in the conversion mechanism when the rotational movement of the valve body is converted into linear movement of the valve body toward the side where the sealing material moves away from the opening formation surface is suppressed. [Effects of the Invention]

[0018] According to the motor-operated valve of the present disclosure, wear of the sealing material is suppressed compared to a configuration in which the sealing material of the valve body is constantly pressed against the surface forming the opening. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view illustrating a motor-operated valve according to an embodiment of the present invention. [Figure 2] FIG. 4 is a bottom perspective view of a second circular plate portion according to the embodiment. [Figure 3] FIG. 3(a) is a side view of the second circular plate according to this embodiment, and FIG. 3(b) is a bottom view of the second circular plate. [Figure 4] FIG. 4(a) is a front view of the valve body of the motor-operated valve according to this embodiment, and FIG. 4(b) is a bottom view of the valve body as seen from the second adjustment unit side. [Figure 5] Figures 5(a1) to (f1) are bottom views showing the position of the pin relative to the second disc portion of the motor-operated valve of this embodiment, Figures 5(a2) to (f2) are partial cross-sectional views viewed from above showing the open and closed states of the first opening by the sealing material corresponding to each state of Figures 5(a1) to (f1), and Figures 5(a3) to (f3) are partial cross-sectional views viewed from a direction perpendicular to the valve body of the open and closed states shown in Figures 5(a2) to (f2), respectively. [Figure 6] FIG. 10 is a cross-sectional view illustrating a motor-operated valve according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0020] This embodiment will be described below. In the following drawings, identical or similar parts are designated by the same or similar reference numerals. However, the drawings are schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each device and each component, etc., differ from the actual ones. Therefore, specific thicknesses and dimensions should be determined with reference to the following description. Furthermore, parts with different dimensional relationships and ratios are included among the drawings. Furthermore, for convenience, the H direction refers to the vertical downward direction.

[0021] <Motor-operated valve configuration> An electric valve 10 according to this embodiment will be described with reference to Figures 1 to 6. As shown in Figure 1, the electric valve 10 includes a can 12, a stator 14, a support member 16, a transmission shaft 18, a rotor 20, a drive shaft 22, a valve body 24, a spring member 26, and a conversion mechanism 60. Figure 1 is a cross-sectional view of the electric valve 10 cut along a vertical plane including an axial center C.

[0022] (Can) The can 12 is a cylindrical member. Any material can be used for the can 12 as long as it can rotate the rotor 20 (described later) inside and has the desired resistance to the fluid flowing therethrough. The can 12 has a bottom 12A and a side wall 12B. The bottom 12A of the can 12 is located on the upper side (opposite the H direction) in FIG. 1, and the opening of the cylindrical can 12 is located on the lower side (H direction) opposite the bottom 12A. FIG. 1 illustrates a state in which the upper part of the valve body 24 fits into the opening of the can 12, thereby joining the can 12 to the valve body 24.

[0023] (stator) The stator 14 is provided on the outside of the can 12 and has a drive coil (not shown). The drive coil rotates a rotor 20 (described later). For clarity, details of the stator 14 are omitted in FIG. 1.

[0024] (support member) The support member 16 is provided inside the can 12 on the side of the bottom 12A (upper side in FIG. 1). A gap is formed between the support member 16 and the bottom 12A. The support member 16 has a first circular plate portion 16A which is a circular plate-like member in a plan view, and a pressing portion 16B provided in the center of the first circular plate portion 16A. The support member 16 may be made of any material, such as resin or metal.

[0025] The outer diameter of the first circular plate portion 16A is approximately equal to the inner diameter of the cylinder of the can 12. The outer end face of the first circular plate portion 16A fits into the inner surface of the side wall portion 12B of the can 12. The support member 16 can slide a certain distance along the axial direction (direction H, up and down in Figure 1) with the first circular plate portion 16A in contact with the inner surface of the side wall portion 12B of the can 12.

[0026] The pressing portion 16B is cylindrical. An opening of the cylindrical pressing portion 16B faces a rotor 20 (described later) located below the pressing portion 16B in FIG. 1. The inner diameter of the cylindrical pressing portion 16B is approximately the same as the outer diameter of a transmission shaft 18 (described later). When one end (the upper end in FIG. 1) of the transmission shaft 18 is inserted into the cylindrical pressing portion 16B, the inner surface of the bottom of the cylindrical pressing portion 16B comes into contact with the end face of one end of the transmission shaft 18 (the upper face in FIG. 1).

[0027] As shown in FIG. 1, a guide groove 16C is provided on the surface of the support member 16 located on the side of the bottom 12A of the can 12 (upper side in FIG. 1) at the boundary between the first circular plate portion 16A and the pressing portion 16B. The guide groove 16C is ring-shaped in plan view. The ring-shaped guide groove 16C runs around the side wall of the pressing portion 16B. The bottom surface of the guide groove 16C is lower than the top surface of the first circular plate portion 16A in FIG. 1.

[0028] A coil spring-shaped spring member 26, which will be described later, is disposed inside the guide groove 16C. The groove width of the guide groove 16C is approximately the same as the width of the spring material of the spring member 26. The lower part of the spring member 26 in FIG. 1 contacts the bottom surface of the guide groove 16C. The upper part of the spring member 26 in FIG. 1 contacts the inner surface of the bottom portion 12A of the can 12.

[0029] (Transmission shaft) The transmission shaft 18 is a rod-shaped member. The transmission shaft 18 extends along the axial direction of the can 12, i.e., along the axial center C in FIG. 1, and transmits the biasing force of a spring member 26, which will be described later, to the valve body 24D. The transmission shaft 18 may be made of any material, such as resin or metal. One end of the transmission shaft 18 is supported by the support member 16. In this embodiment, the one end of the transmission shaft 18 is rotatably supported about the axial center C by the pressing portion 16B of the support member 16. That is, the one end of the transmission shaft 18 is loosely fitted inside the cylindrical pressing portion 16B to such an extent that it is rotatable. The other end of the transmission shaft 18 (the lower end in FIG. 1) is hemispherical. The other end of the transmission shaft 18 is supported by a drive shaft 22, which will be described later.

[0030] (Rotor) The rotor 20 has a cylindrical support body 20A, a sun gear 20B, a planetary gear 20C, a fixed gear 20D, and an output gear 20E. The sun gear 20B, the planetary gear 20C, the fixed gear 20D, and the output gear 20E are disposed inside the support body 20A.

[0031] The support 20A is provided inside the can 12. A through hole is formed in the center of the bottom of the cylindrical support 20A, and the transmission shaft 18 is rotatably inserted into the through hole. The sun gear 20B is rotatably attached to the transmission shaft 18. The planetary gear 20C meshes with the sun gear 20B, and the fixed gear 20D meshes with the planetary gear 20C. The output gear 20E is connected to the planetary gear 20C.

[0032] The sun gear 20B, planetary gear 20C, fixed gear 20D, and output gear 20E, which are formed integrally with the support body 20A, constitute a reduction gear 21. The reduction gear 21 of this embodiment is a reduction gear having a paradox planetary gear mechanism that reduces the rotation of the rotor 20 and outputs it to a drive shaft 22, which will be described later.

[0033] In the reduction gear 21 having the paradox planetary gear mechanism, the sun gear 20B rotates on its axis when output rotation is input from a drive coil (not shown) of the stator 14. As the sun gear 20B rotates on its axis, the planet gear 20C, which meshes with the sun gear 20B and the fixed gear 20D, rotates on its axis and revolves around the sun gear 20B.

[0034] Furthermore, the planetary gear 20C meshes with the output gear 20E, which is shifted relative to the fixed gear 20D. Therefore, due to the rotation of the planetary gear 20C, the output gear 20E can rotate at a relatively high reduction ratio with respect to the fixed gear 20D, for example, a reduction ratio of about 50:1, depending on the degree of shifting (i.e., the difference in the number of teeth).

[0035] In this embodiment, the rotor 20 is disposed away from the support member 16, thereby forming a gap between the rotor 20 and the support member 16. Furthermore, since the transmission shaft 18 is rotatably supported at the axis C by the pressing portion 16B, even if the transmission shaft 18 rotates in conjunction with the rotation of the rotor 20, the support member 16 does not rotate.

[0036] (drive shaft) The drive shaft 22 is a cylindrical member whose axis is aligned with the axial center C. The drive shaft 22 may be made of any material, such as resin or metal. One end of the drive shaft 22 on the transmission shaft 18 side (the upper end in FIG. 1) is connected to the output gear 20E and rotates in conjunction with the output gear 20E. As shown in FIG. 1, a support hole 22A is formed in one end of the drive shaft 22. The drive shaft 22 rotates a valve body 24D, which will be described later. The drive shaft 22 is an example of a shaft body.

[0037] The support hole 22A opens to the side of the transmission shaft 18. In this embodiment, the shape of the support hole 22A is a hemispherical recess that corresponds to the shape (hemispherical) of the other end of the transmission shaft 18.

[0038] The diameter of the support hole 22A is approximately the same as the diameter of the other end of the transmission shaft 18. By inserting the other end of the transmission shaft 18 into the support hole 22A, the transmission shaft 18 is rotatably supported. That is, in a rotating state, one end of the drive shaft 22 supports the other axial end of the transmission shaft 18. In this embodiment, the drive shaft 22 and a valve body 24D, which will be described later, are integrally formed from the same member.

[0039] (Valve body) The valve body 24 is configured by housing a cylindrical member including a valve element inside a bottomed cylindrical member serving as a valve box, and is the main part that functions as a valve in the motor-operated valve 10. Specifically, the valve body 24 has a valve seat 24A, a side wall 24B, a valve chamber 24C, a valve element 24D, a flow path 24E, and a pin hole 24F. The valve seat 24A and the side wall 24B are the main parts of the above-mentioned cylindrical member having the valve chamber 24C, the flow path 24E, and the pin hole 24F. In other words, the valve seat 24A and the side wall 24B are an example of a housing. The valve body 24 allows the valve element 24D to rotate inside the cylindrical member. Any material can be used for the valve body 24 as long as it has the desired resistance to the flowing fluid.

[0040] ((Valve seat and side wall)) The valve seat 24A is formed as the bottom of a cylindrical member and is provided on the other end side (lower side in FIG. 1) of the drive shaft 22 along a plane perpendicular to the axis of the drive shaft 22. A circular first opening 24A1 is formed in the valve seat 24A, connecting the interior of a valve chamber 24C (described later) with the exterior of the valve chamber 24C. The first opening 24A1 penetrates the valve seat 24A in the thickness direction (vertical direction in the figure). The first opening 24A1 is formed so as to be offset from the axis of the drive shaft 22 on the valve seat 24A as a whole. The surface of the valve seat 24A facing the drive shaft 22 is an example of a formed surface. One end of a first pipe 30 having a diameter larger than the inner diameter of the first opening 24A1 is inserted into the valve seat 24A. The first opening 24A1 is connected to the interior of the first pipe 30. The first pipe 30 may be made of any material, such as resin or metal.

[0041] The side wall 24B rises from the periphery of the valve seat 24A and extends toward the rotor 20 (upper side in FIG. 1). The side wall 24B has a second opening 24B1 and a third opening 24B2. One end of the second pipe 32 is inserted into the side wall 24B.

[0042] The second opening 24B1 communicates between the inside of the valve chamber 24C (described later) and the outside of the valve chamber 24C. The second opening 24B1 communicates with the inside of the second pipe 32. The second pipe 32 may be made of any material, such as resin or metal. The first opening 24A1 and the second opening 24B1 form a flow path for the fluid whose flow rate is to be controlled between the first pipe 30 and the second pipe 32.

[0043] The third opening 24B2 connects the inside of the valve body 24 with the outside of the valve body 24 in order to equalize the pressure inside and outside the valve body 24.

[0044] ((Pin hole))

[0045] The pin holes 24F are holes formed in the upper part of the side wall 24B, and open toward the support member 16 side parallel to the axial center C. A pin 62, which will be described later, is embedded in the pin holes 24F. The pin holes 24F fix the pins 62. In this embodiment, two pin holes 24F are formed symmetrically with respect to the axial center C. Furthermore, the pin holes 24F are formed so that a portion of the pin 62 is positioned outside the outer edge of a second circular plate portion 64, which will be described later.

[0046] ((Valve chest)) The valve chamber 24C is a space surrounded by the valve seat 24A and the side wall 24B, and is the internal space of the cylindrical valve body 24. The bottom of the valve chamber 24C is the valve seat 24A. The internal shape of the valve chamber 24C changes depending on the position of the valve element 24D (described later), and allows fluid to circulate between the first pipe 30 and the second pipe 32.

[0047] ((Valve body)) Valve element 24D is cylindrical and includes sealing material 50 and flow path 24E, and is integrally formed on the other end (lower side in FIG. 1) of drive shaft 22. Valve element 24D is rotatable in response to the rotation of drive shaft 22. The rotation of valve element 24D controls the open / closed state of the flow path between first opening 24A1 and second opening 24B1. That is, the rotation of drive shaft 22, which rotates around axis C offset from first opening 24A1, causes valve element 24D to rotate along the upper surface of valve seat 24A, thereby opening and closing first opening 24A1 with sealing material 50, as described below. Specifically, as shown in Fig. 4(a), the valve body 24D of this embodiment has a disk-shaped base 34 and a facing portion 36 provided on the base 34 and having a sector-shaped bottom surface 36B1. The facing portion 36 protrudes from the base 34 toward the valve seat 24A (the lower side in Fig. 4(a)) and faces the upper surface of the valve seat 24A. The facing portion 36 has a first adjustment portion 36A attached to the lower surface of the base 34 in Fig. 4(a) and a second adjustment portion 36B attached to the lower surface of the first adjustment portion 36A.

[0048] As shown in Figures 4(a) and 4(b), the first adjustment unit 36A is a short column (block shape) having a substantially semicircular sector-shaped bottom surface 36A1. More specifically, as shown in Figure 4(b), the central angle of the arc portion of the bottom surface 36A1 of the first adjustment unit 36A relative to the axis center C of the drive shaft 22 is approximately 200 degrees. Note that, in the present disclosure, the central angle of the arc portion of the bottom surface of the first adjustment unit 36A can be changed as appropriate.

[0049] 4(a) and 4(b), the second adjustment portion 36B is a short pillar (block shape) having a sectorial bottom surface 36B1 with a central angle of approximately 90 degrees. In the present disclosure, the central angle of the bottom surface 36B1 of the second adjustment portion 36B can be changed as appropriate.

[0050] The bottom surface 36B1 of the second adjustment portion 36B faces the first opening 24A1. For ease of explanation, the outer edge of the first opening 24A1 is shown by a dashed line inside the bottom surface 36B1 of the second adjustment portion 36B in FIG. 4(b). As shown in FIG. 4(b), the area of ​​the first opening 24A1 covered by the bottom surface 36B1 of the second adjustment portion 36B changes depending on the rotational position of the valve element 24D connected to the drive shaft 22. That is, the first opening 24A1 of the valve seat 24A and the valve element 24D form an orifice as a throttle structure. Therefore, the flow rate of the fluid flowing through the flow path is controlled depending on the rotation of the valve element 24D.

[0051] 4(b), the position of the apex where the two radius portions intersect on the bottom surface 36B1 of the second adjustment portion 36B is outside the axial center C. In other words, the axial center C of the rotation shaft of the valve body 24D is located inside the fan-shaped bottom surface 36B1 of the second adjustment portion 36B. In this embodiment, a support shaft portion protruding from the bottom surface 36B1 is supported in a support hole formed in the valve seat 24A so as to be rotatable around the axial center C.

[0052] A side surface 36A2 of the first adjustment portion 36A and a side surface 36B2 of the second adjustment portion 36B face the second opening 24B1.

[0053] 4(a), for ease of explanation, the opening range of the second opening 24B1 is illustrated by a two-way arrow extending in the up-down direction. As shown in FIGS. 4(a) and 4(b), the degree to which the second opening 24B1 is covered changes with the rotation of the valve body 24D connected to the drive shaft 22.

[0054] Specifically, when first opening 24A1 is at least partially open, first opening 24A1 and second opening 24B1 are at least partially connected to form a flow path, and when first opening 24A1 is open, the flow path is open. On the other hand, when first opening 24A1 is completely closed, the flow path is closed. Note that in this specification, the phrase "changing from an open state to a closed state" is not limited to a change from a fully open state to a fully closed state, but also includes a change from a partially open state to a fully closed state.

[0055] As shown in FIG. 1, a cylindrical sealing material 50 is press-fitted into the second adjustment portion 36B of the valve body 24D from the bottom surface 36B1 side to improve the sealing performance of the first opening 24A1. The sealing material 50 has a diameter slightly larger than the inner diameter of the first opening 24A1. The sealing material 50 can be made using a known material. An example of the material for the sealing material 50 is fluororesin.

[0056] 1, the flow path 24E is a through-hole with a uniform hole diameter formed in the valve body 24D along the axial center C, closer to the side wall 24B than the drive shaft 22, and connecting the valve chamber 24C and the third opening 24B2. The flow path 24E equalizes the internal pressure of the valve body 24.

[0057] (Spring member) The spring member 26 applies a load to the valve body 24D in the axial direction of the drive shaft 22 toward the valve seat 24A. The spring member 26 is an example of a biasing portion. In this embodiment, the spring member 26 is disposed between the bottom 12A of the can 12 and the support member 16. The spring member 26 applies a biasing force as a load to the valve body 24D via the transmission shaft 18 and the drive shaft 22 supported by the support member 16. In this embodiment, the spring member 26 is a metallic compression coil spring. In the present disclosure, the shape and material of the spring member 26 can be changed as desired.

[0058] (Conversion mechanism) The conversion mechanism 60 has a pin 62 and a second circular plate portion 64. The conversion mechanism 60 converts the rotational motion of the valve element 24D into linear motion of the valve element 24D. In this embodiment, the conversion mechanism 60 converts the rotational motion around the axial center C of the drive shaft 22 via the valve element 24D into linear motion in a direction along the axial center C of the drive shaft 22 in which the sealing material 50 moves away from the valve seat 24A. The conversion mechanism 60 is fixed to the valve body 24. The conversion mechanism 60 may be made of any material, such as resin or metal.

[0059] ((pin)) The pin 62 is a rod-shaped member and is an example of a protrusion. In this embodiment, two pins are arranged symmetrically with respect to the axial center C of the drive shaft 22. The pin 62 is fixed to the valve body 24 with the lower part of the pin 62 embedded in the pin hole 24F in the upper part of the side wall 24B of the valve body 24 in FIG. 1. The upper part of the pin 62 is exposed from the upper side of the valve body 24 in FIG. 1. One end of the pin 62 is formed in an arc shape. The pin 62 is made of a material such as SUS.

[0060] ((Second disc part)) As shown in FIGS. 2 and 3 , the second circular plate 64 is a circular plate having a through hole in the center and having an irregular surface on one side. The second circular plate 64 is an example of a plate portion. The second circular plate 64 has an irregular front surface 64H and a flat back surface 64T. The second circular plate 64 is fixed to the drive shaft 22 by a fixing means (not shown) with the front surface 64H facing the pin 62 and the back surface 64T aligned along a plane perpendicular to the axis C. The second circular plate 64 rotates together with the valve element 24D about the axis C. In this embodiment, the second circular plate 64 has a larger diameter than the valve element 24D (base 34) that fits within the side wall 24B, and its outer edge portion covers the pin 62 embedded in the upper end of the side wall 24B from above. In this embodiment, a portion of the pin 62 is located outside the outer edge of the second circular plate 64. The second disk portion 64 converts the rotational motion of the valve body 24D into linear motion by changing the position with which the pin 62 contacts as the valve body 24D rotates. This will be explained in more detail below.

[0061] The second circular plate portion 64 has an uneven portion formed in a certain range W extending from the outer edge of the second circular plate portion 64 toward the back surface 64T from the front surface 64H. The uneven portion is formed of a reference surface 66C, a first inclined surface 66A, a seat surface 66B, a second inclined surface 66D, and an adjustment surface 66E, arranged in this order in the direction opposite to the rotation direction of the drive shaft 22. In this embodiment, the range occupied by the reference surface 66C, the first inclined surface 66A, the seat surface 66B, the second inclined surface 66D, and the adjustment surface 66E is semicircular (180°), and this range is formed in two periods within the range W. Here, the rotation direction of the drive shaft 22 refers to the clockwise direction when viewed from the back to the front in FIG. 3(b), and the direction opposite to the rotation direction refers to the counterclockwise direction (the direction indicated by arrow R) when viewed from the front to the back in FIG. 3(b).

[0062] The reference surface 66C is an arc-shaped flat surface that is configured parallel to the back surface 64T of the second circular plate portion 64. The reference surface 66C is disposed closer to the back surface 64T than the front surface 64H in the plate thickness direction (H direction) of the second circular plate portion 64. While the reference surface 66C is positioned on the pin 62, the sealing material 50 of the valve body 24D, which will be described later, is urged against the valve seat 24A.

[0063] The first inclined surface 66A is disposed adjacent to the reference surface 66C and is an arc-shaped inclined surface that follows the outer edge of the second circular plate portion 64 and has a constant gradient from the reference surface 66C toward the surface 64H. In this embodiment, the central angle of the arc of the first inclined surface 66A is approximately 140°. While the first inclined surface 66A is positioned on the pin 62, the sealing material 50 of the valve body 24D receives a force from the displacement mechanism 60 in a direction away from the valve seat 24A. For example, while the middle portion of the first inclined surface 66A is positioned on the pin, the sealing material 50 of the valve body 24D is away from the valve seat 24A.

[0064] The seat surface 66B is disposed adjacent to the first inclined surface 66A and is a flat, arc-shaped surface that follows the outer edge of the second circular plate portion 64. While the seat surface 66B is positioned on the pin 62, the sealing material 50 of the valve body 24D is farthest from the valve seat 24A. The distance between the reference surface 66C and the seat surface 66B in the thickness direction of the second circular plate portion 64 is, for example, 0.1 mm.

[0065] The second inclined surface 66D is disposed adjacent to the seat surface 66B and is an arc-shaped inclined surface that extends along the outer edge of the second circular plate portion 64 and has a constant gradient toward the reference surface 66C. The gradient of the second inclined surface 66D faces in the opposite direction to the gradient of the first inclined surface 66A, and the absolute value of the gradient of the second inclined surface 66D (the gradient angle relative to the reference surface) is greater than the absolute value of the gradient of the first inclined surface 66A. In this embodiment, the central angle of the arc of the second inclined surface 66D is approximately 10°. While the second inclined surface 66D is positioned on the pin 62, the seal material 50 of the valve body 24D is closer to the valve seat 24A than when the seal material 50 is positioned on the seat surface 66B.

[0066] The adjustment surface 66E is a step disposed between the second inclined surface 66D and the reference surface 66C. The adjustment surface 66E can be said to be mainly a wall surface that continues from the second inclined surface 66D and extends along the axis center C. A portion below the wall surface that continues to the reference surface 66C is chamfered to correspond to the shape of one end of the pin 62.

[0067] The reference surface 66C, first inclined surface 66A, seat surface 66B, second inclined surface 66D, and adjustment surface 66E described above can be considered to form a cam surface that contacts the pin 62 on the surface 64H and on the back surface 64T side of the surface 64H of the second circular plate portion 64. This cam surface is pressed against the pin 62 by the biasing force of the spring member 26, and the pin 62 functions as a cam follower. In other words, the conversion mechanism 60 is configured to convert the rotational motion of the valve disc 24D into linear motion by changing the circumferential and axial contact positions with the pin 62 on the surface 64H and on the back surface 64T side of the surface 64H as the valve disc 24D rotates, as described above.

[0068] 5(a1) to (f1), in the motor-operated valve 10 according to this embodiment, the opening and closing state of the first opening 24A1 by the sealing material 50 changes depending on the position of each surface of the second circular plate portion 64 relative to the pin 62. Specifically, when the rotor 20 is rotated by the stator 14, the drive shaft 22, the transmission shaft 18, and the valve body 24D rotate integrally in conjunction with the rotation of the rotor 20. When the valve body 24D rotates, the second circular plate portion 64 rotates relative to the pin 62, and the sealing material 50 of the valve body 24D opens or closes the first opening 24A1. For ease of explanation, in FIGS. 5(a1) to 5(f1), attention is focused on the movement of one pin 62, and explanation and illustration of the other pins 62 are omitted.

[0069] In Fig. 5(a1), the reference surface 66C1 of the second circular plate portion 64 is positioned on the pin 62. The position of the sealing material 50 corresponding to this position is a position overlapping the first opening 24A1 as shown in Fig. 5(a2), and is a position that closes the first opening 24A1 as shown in Fig. 5(a3). In other words, the sealing material 50 is biased against the valve seat 24A.

[0070] FIG. 5(b1) shows a state in which the valve disc 24D has rotated in the rotational direction of the drive shaft 22 from the state shown in FIG. 5(a1). Specifically, in FIG. 5(b1), the boundary between the reference surface 66C1 and the first inclined surface 66A1 of the second circular plate portion 64 is located on the pin 62. The position of the sealing material 50 corresponding to this position is offset from the first opening 24A1, as shown in FIG. 5(b2), and the first opening 24A1 is open. In this state, the load exerted by the spring member 26 of the sealing material 50 due to contact between the sealing material 50 and the valve seat 24A is released. In other words, the rotational movement of the valve disc 24D from FIG. 5(a1) to FIG. 5(b1) causes the valve disc 24D to start linear movement along the axial center C.

[0071] FIG. 5(c1) shows a state in which the valve disc 24D has rotated in the rotational direction of the drive shaft 22 from the state shown in FIG. 5(b1). Specifically, in FIG. 5(c1), the first inclined surface 66A1 of the second circular plate portion 64 is positioned on the pin 62. The position of the sealing material 50 corresponding to this position is a position away from the first opening 24A1, as shown in FIG. 5(c2). Furthermore, as shown in FIG. 5(c3), the first opening 24A1 is open, and the sealing material 50 is away from the valve seat 24A. In this state, no load is generated by the spring member 26 of the sealing material 50 due to contact between the sealing material 50 and the valve seat 24A. In other words, the rotational motion of the valve disc 24D from FIG. 5(b1) to FIG. 5(c1) is converted into linear motion in the direction opposite to the direction H along the axial center C of the valve disc 24D, resisting the biasing force of the spring member 26.

[0072] Figure 5(d1) shows a state in which the valve element 24D has rotated in the rotational direction of the drive shaft 22 from the state shown in Figure 5(c1). Specifically, in Figure 5(d1), the reference surface 66C2 of the second circular plate portion 64 is positioned on the pin 62. The position of the sealing material 50 corresponding to this position is a position away from the first opening 24A1, as shown in Figure 5(d2). Furthermore, as shown in Figure 5(d3), the sealing material 50 is biased against the valve seat 24A on the opposite side of the axial center C from the first opening 24A1.

[0073] FIG. 5(e1) shows a state in which the valve element 24D has rotated approximately 150° in the rotational direction of the drive shaft 22 from the state shown in FIG. 5(d1). Specifically, in FIG. 5(e1), the seat surface 66B1 of the second circular plate portion 64 is positioned on the pin 62. The position of the sealing material 50 corresponding to this position is a position in which it partially overlaps the first opening 24A1, as shown in FIG. 5(e2). However, as shown in FIG. 5(e3), the sealing material 50 is separated from the valve seat 24A (open state). In other words, no load is generated by the spring member 26 of the sealing material 50 when the sealing material 50 comes into contact with the valve seat 24A.

[0074] Figure 5(f1) shows a state in which the valve body 24D has rotated in the rotational direction of the drive shaft 22 from the state shown in Figure 5(e1). Specifically, in Figure 5(f1), the reference surface 66C1 of the second circular plate portion 64 is positioned on the pin 62. More specifically, the second inclined surface 66D is no longer on the pin 62, and the side surface of the pin 62 is aligned with the adjustment surface 66E, which is a wall surface, so that the reference surface 66C is positioned on the pin 62. As shown in Figure 5(f2), the position of the sealing material 50 corresponding to this position is one in which it overlaps further with the first opening 24A1 than in the state shown in Figure 5(e2), but the first opening 24A1 is slightly open.

[0075] When the valve element 24D rotates in the rotation direction of the drive shaft 22 from the state shown in FIG. 5(f1), it returns to the state shown in FIG. 5(a1).

[0076] As described above, the opening and closing state of the flow path is controlled by the rotation of the valve element 24D, that is, the flow rate is controlled.

[0077] <Action and effect> The electric valve 10 of this embodiment comprises a valve seat 24A having a first opening 24A1, a drive shaft 22 extending in a direction perpendicular to the valve seat 24A and rotating around an axial center offset from the first opening 24A1, a valve body 24D having a sealing material 50 and attached to the drive shaft 22, which rotates along the valve seat 24A as the drive shaft 22 rotates, thereby opening and closing the first opening 24A1 with the sealing material 50, a spring member 26 which urges the valve body 24D toward the valve seat 24A, and a conversion mechanism 60 which converts at least the rotational movement of the valve body 24D from a state in which the sealing material 50 closes the first opening 24A1 to a state in which the sealing material 50 opens it, into linear movement of the valve body 24D in a direction in which the sealing material 50 moves away from the valve seat 24A. In the motor-operated valve 10, when the valve element 24D rotates from a state in which the first opening 24A1 is closed to the opening side, the conversion mechanism 60 converts the rotational motion of the valve element 24D into linear motion, causing the sealing material 50 to act in a direction away from the valve seat 24A. As a result, in the motor-operated valve 10, wear of the sealing material 50 is suppressed compared to a configuration in which the sealing material 50 of the valve element 24D is constantly pressed against the valve seat 24A.

[0078] Furthermore, in the motor-operated valve 10 according to this embodiment, the conversion mechanism 60 includes a pin 62 disposed on the side wall 24B and projecting away from the valve seat 24A, and a second circular plate 64 disposed on the side of the valve element 24D facing the pin 62 and having a first inclined surface 66A inclined relative to the valve seat 24A, the pin 62 moving along the first inclined surface 66A as the drive shaft 22 rotates. In the motor-operated valve 10, the pin 62 on the side of the side wall 24B contacts the second circular plate 64 on the side of the valve element 24D due to the biasing force of the spring member 26. When the first inclined surface 66A moves along the pin 62 as the valve element 24D rotates, the rotational motion of the valve element 24D is converted into linear motion. In this electric valve 10, the second disc portion 64 has a first inclined surface 66A with a complex shape, so the direction of movement of the valve body 24D changes with a simpler configuration than a configuration in which an inclined surface is arranged on the side wall 24B or the base 34 of the valve body 24D.

[0079] Furthermore, in the motor-operated valve 10 according to this embodiment, the pin 62 and the first inclined surface 66A of the second circular plate portion 64 are both positioned outward from the valve body 24D when viewed in the direction along the axial center C. In this motor-operated valve 10, the sealing material 50 moves away from the valve seat 24A with a smaller load than in a configuration in which the pin 62 and the first inclined surface 66A of the second circular plate portion 64 are positioned between the axial center C of the drive shaft 22 and the outer edge of the valve body 24D.

[0080] Furthermore, in the motor-operated valve 10 according to this embodiment, the second circular plate portion 64 has a flat seat surface 66B that continues from the first inclined surface 66A in the direction opposite to the rotational direction of the drive shaft 22. In the motor-operated valve 10, the sealing material 50 of the valve body 24D is maintained at a distance away from the valve seat 24A while the seat surface 66B passes the pin 62, so the power resisting the biasing force of the spring member 26 is reduced compared to a configuration in which the second circular plate portion 64 has only an inclined surface.

[0081] Furthermore, in the motor-operated valve 10 according to this embodiment, the second circular plate portion 64 is formed adjacent to the seating surface 66B in a direction away from the valve seat 24A and in the opposite direction to the rotational direction of the drive shaft 22, and has a reference surface 66C along which the pin 62 moves when the sealing material 50 changes from a state in which it opens the first opening 24A1 to a state in which it closes it. In the motor-operated valve 10, when the contact surface of the pin 62 on the second circular plate portion 64 moves from the seating surface 66B to the reference surface 66C as the drive shaft 22 rotates, the sealing material 50 comes into contact with the valve seat 24A. Furthermore, when the reference surface 66C moves along the pin 62 as the drive shaft 22 rotates, the sealing material 50 changes from a state in which it opens the first opening 24A1 to a state in which it closes it. As a result, in this electric valve 10, cracking or chipping of the sealing material 50 due to the edge of the first opening 24A1 is suppressed compared to a configuration in which the first opening 24A1 is closed when the contact surface of the pin 62 extends from the base surface 66B to the reference surface 66C while the sealing material 50 overlaps the first opening 24A1.

[0082] In the motor-operated valve 10 according to this embodiment, a pair of conversion mechanisms 60 are arranged symmetrically with respect to the axial center of the drive shaft 22. In this motor-operated valve 10, compared to when there is only one conversion mechanism 60, tilt that occurs in the second circular plate portion 64 of the conversion mechanism 60 when the rotational motion of the valve element 24D is converted into linear motion of the valve element 24D in the direction away from the seal material 50 valve seat 24A is suppressed.

[0083] Although the present disclosure has been described using the above disclosed embodiments, the descriptions and drawings that form part of this disclosure should not be understood to limit the present disclosure. For example, the present disclosure can also be configured by partially combining the configurations shown in Figures 1 to 7. The present disclosure includes various embodiments not described above, and the technical scope of the present disclosure is defined only by the invention-specifying matters in the claims that are appropriate from the above description.

[0084] <Modification> (motor-operated valve) This modified example differs from the above embodiment in that the second circular plate portion 64 and the output gear 20E are integrated, but all other configurations are the same. As shown in Fig. 6, in this modified example, unevenness is formed on one surface of the output gear 120E on the valve seat 24A side. In this modified example, the shape of the output gear 120E is changed without adding the second circular plate portion 64 in the above embodiment, so the number of parts is reduced compared to the configuration in which the second circular plate portion 64 is added.

[0085] In the above embodiment, the drive shaft 22 rotates in a fixed direction, but this is not limiting. For example, the drive shaft 22 may be rotated in the opposite direction. In this case, an initialization operation (returning to the origin) becomes possible by abutting the side surface of the pin 62 against the adjustment surface 66E of the second circular plate portion 64.

[0086] (Transmission shaft) One end of the transmission shaft 18 is loosely fitted into the cylindrical pressing portion 16B to a degree that allows rotation, but this is not limited to this. For example, one end of the transmission shaft 18 may be fixed to the inside of the cylindrical pressing portion 16B. Furthermore, the shape of the other end of the transmission shaft 18 is hemispherical, but this is not limited to this. For example, the other end of the transmission shaft 18 may be appropriately modified to have a conical shape that tapers toward the drive shaft 22.

[0087] (Decelerator) Although the reduction gear 21 is a paradox planetary gear mechanism, this is not limiting. For example, the reduction gear 21 may be a reduction gear having a gear configuration other than a paradox planetary gear mechanism, such as a 2K-H multi-stage reduction gear having two sun gears and one output gear. Furthermore, although a planetary gear mechanism is employed as the rotor 20 in the above embodiment, this is not limiting. As long as it can rotate the drive shaft 22, a rotation transmission structure other than a planetary gear mechanism may be employed.

[0088] (drive shaft) In the above embodiment, the shape of the support hole 22A in the drive shaft 22 is a hemispherical recess corresponding to the shape of the other end of the hemispherical transmission shaft 18, but this is not limiting. For example, the shape of the support hole 22A may be conical or the like as long as it is formed corresponding to the shape of the other end of the transmission shaft 18. Furthermore, although the drive shaft 22 and the valve body 24D are integrally formed from the same member, this is not limiting. For example, the drive shaft 22 and the valve body 24 may be manufactured as separate members and then integrated by being connected to each other.

[0089] (Valve body) Although the first opening 24A1 and the second opening 24B1 have been described as forming a flow path for a fluid to be subjected to flow rate control between the first pipe 30 and the second pipe 32, this is not limiting. For example, at least one of the first pipe 30 and the second pipe 32 may be included in the flow path. Furthermore, although the first opening 24A1 has been described as being circular, this is not limiting.

[0090] In the present embodiment, the sealing material 50 is separated from the valve seat 24A, but this is not limiting. Even when the sealing material 50 is biased against the valve seat 24A, by varying the biasing force of the spring member 26 to an extent that the sealing material 50 is elastically deformed, wear of the sealing material 50 is suppressed compared to a configuration in which the biasing force does not vary.

[0091] (Spring material) Although the spring member 26 is a metal coil spring, it is not limited to this. For example, the spring member 26 may be a leaf spring or other spring member. Furthermore, the number of turns of the spring member of the coil spring is about several times, but it is not limited to this. For example, the number of turns can be set appropriately depending on the magnitude of the desired load.

[0092] (Conversion mechanism) Although the pin 62 is described as a rod-shaped member, the present invention is not limited to this. For example, the pin 62 may be an elliptical cylinder, a rectangular cylinder, or other columnar member, or a hemisphere, a cone, a pyramid, a frustum, or other convex member formed integrally or separately on the side wall 24B.

[0093] Although the second circular plate portion 64 is described as having the reference surface 66C, the first inclined surface 66A, the seat surface 66B, the second inclined surface 66D, and the adjustment surface 66E arranged thereon, the present invention is not limited to this. For example, the second circular plate portion 64 may be provided with only the single first inclined surface 66A arranged thereon.

[0094] In addition, the second circular plate portion 64 has the reference surface 66C, the first inclined surface 66A, the seat surface 66B, the second inclined surface 66D, and the adjustment surface 66E arranged in this order for two periods in the direction opposite to the rotational direction of the drive shaft 22. However, this is not limited to this. For example, each of these surfaces may be arranged for one period or three or more periods on the second circular plate portion 64.

[0095] Furthermore, although the second circular plate portion 64 has been described as having each surface disposed within a certain range W continuously from the outer edge of the second circular plate portion 64, this is not limited to this. For example, each surface may be disposed within a certain range from a position away from the outer edge of the second circular plate portion 64 toward the axial center C, or a chamfered portion may be provided on the outer edge of the second circular plate portion 64, and each surface may be disposed on that portion. When these exemplary configurations are employed, the pins 62 are configured at positions corresponding to each surface of the second circular plate portion 64.

[0096] Furthermore, the second disk portion 64 is not limited to this, as long as it converts the rotational motion of the valve element 24D into linear motion of the valve element 24D together with the pin 62 as part of the conversion mechanism 60. For example, the second disk portion 64 may be an elastic body that elastically deforms at least in the direction along the axial center C, such as a leaf spring.

[0097] Furthermore, although the multiple first inclined surfaces 66A are arranged at 180° intervals within a predetermined range from the outer edge of the second circular plate portion, this is not limited to this. The first inclined surfaces 66A may be arranged to be offset from one another in the radial direction of the second circular plate portion 64, or a single first inclined surface 66A may be arranged on each of the multiple second circular plate portions 64, and the second circular plate portions 64 may be stacked in the axial direction with the phases of the second circular plate portions 64 offset. When these exemplary configurations are adopted, the pins 62 are arranged at positions corresponding to the respective surfaces of the second circular plate portion 64.

[0098] Although the first inclined surface 66A is an inclined surface having a constant gradient, the present invention is not limited to this. For example, the first inclined surface 66A may be an inclined surface whose gradient changes depending on the position. [Explanation of symbols]

[0099] 10 Motor-operated valve 12 Can 14 Stator 16 Support member 18 Transmission shaft 20 rotors 21 Reducer 22 Drive shaft (example of shaft) 24 Valve body 24A1 First opening (an example of an opening) 24A Valve seat (example of housing and forming surface) 24B Side wall (example of enclosure) 24C Valve chamber 24D valve body 26 Spring member (an example of a biasing portion) 50 Sealing material 60 Conversion Mechanism 62 Pin (example of convex part) 64 Second disc portion (an example of a disc portion) 64D Valve body 66A, 66A1 First inclined surface (an example of an inclined surface) 66B, 66B1 base surface 66C, 66C1, 66C2 reference plane

Claims

1. a housing having an opening; a shaft extending in a direction perpendicular to a surface where the opening is formed and rotating around an axis center offset from the opening; a valve body having a sealing material, the valve body being provided on the shaft body and rotating along the forming surface by rotation of the shaft body to open and close the opening by the sealing material; a biasing portion that biases the valve body toward the forming surface; a conversion mechanism that converts at least the rotational movement of the valve body from a state in which the sealing material closes the opening to a state in which the sealing material opens the opening into a linear movement of the valve body in a direction away from the forming surface of the sealing material; Equipped with The conversion mechanism is a protrusion disposed on the housing and protruding in a direction away from a surface where the opening is formed; a plate portion disposed on a side of the valve body facing the protrusion, the plate portion having an inclined surface inclined with respect to a surface on which the opening is formed, the protrusion portion moving along the inclined surface as the shaft body rotates; An electric valve having

2. The protrusion and the inclined surface of the plate are both positioned outward from the valve body when viewed in a direction along the axis center. The motor-operated valve according to claim 1.

3. The plate portion continues from the inclined surface in the direction opposite to the rotation direction of the shaft body and has a flat base surface. The motor-operated valve according to claim 2.

4. The plate portion is formed adjacent to the base surface in a direction away from the opening formation surface than the base surface and in a direction opposite to the rotation direction of the shaft body, and has a reference surface along which the convex portion moves when the sealing material changes from a state in which the opening is opened to a state in which the opening is closed. The motor-operated valve according to claim 3.

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