JP2024015519A - Motor valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor valve capable of downsizing itself in a simple structure while suppressing pressure loss or others if possible.

SOLUTION: The motor valve includes a motor, a driven part including a flange portion so to be rotationally driven by the motor, and a casing including an inflow path on the high pressure side of fluid and a discharge path on the low pressure side, for storing the driven part, the flange portion having plural through-openings and shield walls, and circular ribs formed on the peripheries of the plural through-openings and shield walls, respectively. According to the rotational position of the driven part, any one of the plural through-openings and shield walls is selectively arranged between the inflow path and the discharge path. The plural through-openings includes mutually different number of openings and cross section areas, and the number of openings is greater as the cross section area is smaller.

SELECTED DRAWING: Figure 3

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to an electric valve.

2. Description of the Related Art Conventionally, electric valves have been used, for example, as devices that are placed in the middle of a fluid piping system to open and close a fluid flow path and control the flow rate. In such an electric valve, in order to accurately control the flow rate, the valve body is driven by a driving source such as a stepping motor attached to the valve body.

Patent Document 1 discloses that by driving the valve body with a stepping motor and separating it from the valve seat, fluid such as refrigerant is allowed to flow between the first port and the second port, and the valve body is moved away from the valve seat. A motor-operated valve is disclosed that prevents fluid flow between a first port and a second port by being seated on the motor-operated valve.

Japanese Patent Application Publication No. 2019-173877

In the electric valve of Patent Document 1, a conversion mechanism using a screw is used to convert the rotational movement of the stepping motor into linear movement of the valve body. Therefore, in addition to the complicated structure, the sliding resistance of the screw is relatively large, so it is necessary to increase the capacity of the stepping motor, leading to an increase in the size and cost of the electric valve.

Further, in the electric valve of Patent Document 1, since the valve shaft connected to the valve body extends along the central axis of the valve seat, the first port and the second port are connected to each other in order to avoid interference with the valve shaft. It is necessary to arrange one of them in a direction intersecting the axis of the valve seat. Therefore, the fluid flow between the first port and the second port is forced to change direction, resulting in problems such as pressure loss. Further, in the electric valve of Patent Document 1, it is difficult to realize bidirectional flow due to its structure.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electric valve that has a simple structure, can be downsized, and can suppress pressure loss as much as possible.

The electric valve according to the present invention includes:
motor and
a driven part including a flange part and rotationally driven by the motor;
a casing that includes a fluid inflow path on a high pressure side and a fluid discharge path on a low pressure side, and houses the driven part;
The flange portion has a plurality of through openings, a shielding wall, and a circular rib formed around each of the plurality of through openings and the shielding wall, and the flange portion has a plurality of through openings, a shielding wall, and a circular rib formed around each of the through openings and the shielding wall. , any one of the plurality of through openings and the shielding wall is selectively disposed between the inlet channel and the outlet channel,
The plurality of through openings have different numerical apertures and cross-sectional areas, and the smaller the cross-sectional area, the larger the numerical aperture.

According to the present invention, it is possible to provide an electric valve that has a simple structure, can be downsized, and can suppress pressure loss as much as possible.

FIG. 1 is a perspective view of the electric valve of this embodiment, viewed from the motor section side. FIG. 2 is a perspective view of the electric valve of this embodiment as viewed from the gear part side, with a part of the gear case removed. FIG. 3 is a cross-sectional view of the gear section taken along a plane passing through the axis of the gear, and a part of the motor section is omitted. FIG. 4 is a perspective view of the second gear part of this embodiment. FIG. 5 is a perspective view of a second gear section of a modified example.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an electric valve according to the present invention will be described with reference to the drawings. The electric valve 1 of this embodiment can be connected to, for example, piping of a refrigeration cycle and used to control the flow of refrigerant.

(Structure of electric valve)
FIG. 1 is a perspective view of the electric valve 1 of this embodiment, viewed from the motor section side. FIG. 2 is a perspective view of the electric valve 1 of this embodiment viewed from the gear part 3 side, with a part of the gear case removed. FIG. 3 is a cross-sectional view of the gear section cut along a plane passing through the axes of the driving gear and the driven gear, and a part of the motor section 2 is omitted.

The electric valve 1 has a motor section 2 and a gear section 3. The motor section 2 includes a motor base 21 made of a metal plate, and a cover 22 made of resin and having a cylindrical shape with a bottom and connected to the motor base 21. A stepping motor (not shown) is housed in an internal space formed by the motor base 21 and the cover 22.

A part of the outer periphery of the cover 22 extends radially outward and is connected to a hollow box 23, and a board connected to a terminal pin 24 passing through the box 23 is disposed inside the box 23. There is. The stepping motor receives power from an external control device via the board and terminal pins 24.

The gear part 3 includes a case base 31 connected to the motor base 21 via a screw SC (FIG. 1), a gear case 32 connected to the case base 31, and a gear formed between the case base 31 and the gear case 32. It has a first gear part 33 and a second gear part 34 arranged in the chamber GC. The case base 31 and the gear case 32 constitute a housing.

The case base 31 has a shaft hole 311 penetrating in the thickness direction, a first recess 312 formed on the surface facing the gear chamber GC, and a first recess 312 formed on the surface opposite to the surface facing the gear chamber GC. A first piping connection portion 313 is provided. The first bottom surface 314 of the first recess 312 is spherical. A first flow path 315 having a circular cross section is formed inside a first pipe connecting portion 313 connected to a pipe (not shown). The inner diameter of the first flow path 315 is equal to the inner diameter of circular ribs 34A to 34F, which will be described later. A first annular portion 316 is formed on the surface of the case base 31 facing the gear chamber GC so as to protrude around the first flow path 315 .

The gear case 32 has a plate-shaped part 321 extending parallel to the case base 31 and a cylindrical part 322 extending from the outer periphery of the plate-shaped part 321 toward the case base 31. By abutting and fixing the end of the cylindrical portion 322 against the case base 31, a sealed gear chamber GC is formed inside the cylindrical portion 322.

On the surface of the plate-shaped portion 321 facing the gear chamber GC of the gear case 32, a second recess 323 is formed opposite to the shaft hole 311, and a third recess 324 is formed opposite to the first recess 312. There is. The second bottom surface 325 of the second recess 323 and the third bottom surface 326 of the third recess 324 are each spherical.

A second pipe connection portion 327 is formed on a surface of the plate portion 321 opposite to the surface facing the gear chamber GC so as to face the first pipe connection portion 313 . A second flow path 328 having a circular cross section is formed inside a second pipe connecting portion 327 connected to a pipe (not shown). The inner diameter of the second flow path 328 is equal to the inner diameter of circular ribs 34A to 34F, which will be described later. A second annular portion 329 is formed on the surface of the plate-shaped portion 321 facing the gear chamber GC so as to protrude around the second flow path 328 . The second annular portion 329 faces the first annular portion 316 with an interval therebetween.

The first gear section 33 is formed by connecting a first shaft 331 that is integrated with the output shaft of a stepping motor and a drive gear 332 coaxially formed around the first shaft 331. The tip 333 of the first shaft 331 has a spherical shape corresponding to the second bottom surface 325 of the second recess 323 of the plate-shaped portion 321 . The first shaft 331 is fitted into the shaft hole 311 and the second recess 323 so as to be relatively rotatable, and the second bottom surface 325 serves as a bearing portion for the first shaft 331.

The second gear part 34, which is a driven part, includes a cylindrical second shaft 341, a disc-shaped flange part 342 coaxially formed around the second shaft 341, and a disc-shaped flange part 342 formed on the outer periphery of the flange part 342. A driven gear 343 is provided in series. The driven gear 343 meshes with the drive gear 332.

One end 344 of the second shaft 341 has a spherical shape corresponding to the first bottom surface 314 of the first recess 312 of the case base 31 , and the other end 345 has a third Corresponding to the bottom surface 326, it has a spherical shape. The second shaft 341 is fitted into the first recess 312 and the third recess 324 so as to be relatively rotatable, and the first bottom surface 314 or the third bottom surface 326 serves as a bearing section for the second shaft 341.

FIG. 4 is a perspective view of the second gear section 34. In the figure, on both sides of the flange portion 342, a small diameter rib 3421 and a large diameter rib 3422 (only one shown) are arranged concentrically with respect to the second axis 341 at the same height (distance from the surface of the flange portion 342). It is formed in

On both sides of the flange portion 342, between the small diameter rib 3421 and the large diameter rib 3422, six circular ribs 34A to 34F (only one shown) are arranged at equal intervals in the circumferential direction at opposing positions with the flange portion 342 in between. It is formed. The six circular ribs 34A to 34F have the same diameter and the same height (distance from the surface of the flange portion 342) as the small diameter rib 3421 and the large diameter rib 3422. A portion of the circular ribs 34A to 34F are fused with the small diameter rib 3421 and the large diameter rib 3422.

The inner sides of the circular ribs 34A-34F have different shapes. Specifically, an opening 34A1 is formed inside the circular rib 34A. The inner diameter of the opening 34A1 is equal to the inner diameter of the circular rib 34A.

The inner side of the circular rib 34B adjacent to the circular rib 34A is shielded by a shielding wall 34B1.

A wall 34C1 and five first circular openings 34C2 passing through the wall 34C1 are formed inside the circular rib 34C adjacent to the circular rib 34B. The total cross-sectional area of the first circular openings 34C2 is smaller than the cross-sectional area of the openings 34A1.

A wall 34D1 and thirteen second circular openings 34D2 passing through the wall 34D1 are formed inside the circular rib 34D adjacent to the circular rib 34C. The inner diameter of the second circular opening 34D2 is smaller than the inner diameter of the first circular opening 34C2.

A wall 34E1 and a third circular opening 34E2 passing through the wall 34E1 are formed inside the circular rib 34E adjacent to the circular rib 34D. The inner diameter of the third circular opening 34E2 is smaller than the inner diameter of the second circular opening 34D2, and the number of third circular openings 34E2 is greater than the number of second circular openings 34D2.

A wall 34F1 and a fourth circular opening 34F2 passing through the wall 34F1 are formed inside the circular rib 34F adjacent to the circular rib 34E. The inner diameter of the fourth circular opening 34F2 is smaller than the inner diameter of the third circular opening 34E2, and the number of fourth circular openings 34F2 is greater than the number of third circular openings 34E2. The total cross-sectional area of the first to fourth circular openings 34C2 to 34F2 is preferably different from each other. The opening 34A1 and the first circular opening 34C2 to the fourth circular opening 34F2 constitute a through opening.

When the electric valve 1 is assembled, the circular ribs 34A to 34F formed on both sides of the flange portion 342 are attached to the first annular portion 316 and the second annular portion 329 depending on the rotational position of the second gear portion 34. opposite. The gap between the first annular portion 316 and the second annular portion 329 is slightly larger than the distance between the axial ends of the opposing circular ribs 34A to 34F.

(Operation of electric valve)
Here, the stepping motor of the motor section 2 has a built-in encoder that detects the rotation angle of the output shaft, that is, the first gear section 33, and the rotation angle of the first gear section 33 is determined in a closed loop based on the signal from the encoder. However, the stepping motor may be controlled by open loop control.

By transmitting a control signal from a control device (not shown) to the stepping motor of the motor section 2 via the terminal pin 24, the first The second gear section 34 rotates.

Note that the control device takes into account the gear ratio of the first gear portion 33 and the second gear portion 34 and determines the angular position at which one of the circular ribs 34A to 34F faces the first annular portion 316 and the second annular portion 329. It is assumed that the angular position of the first gear section 33, which can be moved up to 1, is stored in advance. The position where the circular ribs 34A, 34C to 34F face the first annular part 316 and the second annular part 329 is the valve open position, and the position where the circular rib 34B faces the first annular part 316 and the second annular part 329 is the valve open position. The valve is in the closed position.

The first flow path (inflow path here) 315 side is defined as the refrigerant inflow side (high pressure side), and the second flow path (here outflow path) 328 side is defined as the refrigerant outflow side (low pressure side). When it is desired to cut off the flow of the refrigerant between the first flow path 315 and the second flow path 328, the control device drives the stepping motor to move the circular rib 34B to the first annular portion 316 and the second annular portion 329. The second gear section 34 is rotated to the opposing position.

Since the inside of the circular rib 34B is closed by the shielding wall 34B1, the flow of the refrigerant from the first flow path 315 toward the second flow path 328 can be blocked.

At this time, the second gear portion 34 is displaced in the axial direction due to the pressure difference between the high pressure side and the low pressure side, and the circular rib 34B on the low pressure side abuts the second annular portion 329 around the entire circumference. Thereby, a seal is established between the circular rib 34B and the second annular portion 329, and no refrigerant leakage occurs.

On the other hand, since a gap is created between the high-pressure side circular rib 34B and the first annular portion 316, the refrigerant flows into the gear chamber GC through the gap. This refrigerant can be used to lubricate the first gear section 33, the second gear section 34, the first shaft 331, and the second shaft 341. Even if the inside of the gear chamber GC is filled with refrigerant, the refrigerant will not flow out into the second flow path 328 because the low-pressure side circular rib 34B and the second annular portion 329 are in contact with each other around the entire circumference.

On the other hand, when it is desired to flow the refrigerant at the maximum flow rate between the first flow path 315 and the second flow path 328, the control device drives the stepping motor so that the circular rib 34A The second gear portion 34 is rotated to a position facing the second annular portion 329.

As a result, the opening 34A1, which is formed inside the circular rib 34A and has the largest cross-sectional area, is connected to the first flow path 315 and the second flow path 328 without creating a step difference. The maximum flow rate of the refrigerant from the flow path 315 toward the second flow path 328 can be ensured. Further, since the refrigerant flowing from the first flow path 315 to the second flow path 328 passes straight through the opening 34A1 without stagnation, pressure loss can be suppressed, and the generation of abnormal noise can be suppressed.

Furthermore, if it is desired to flow the refrigerant at a flow rate lower than the maximum flow rate between the first flow path 315 and the second flow path 328, the control device drives the stepping motor so that any one of the circular ribs 34C to 34F The second gear part 34 is rotated to a position opposite the first annular part 316 and the second annular part 329.

Since openings 34C2 to 34F2 with different cross-sectional areas are formed inside the circular ribs 34C to 34F, the maximum width from the first flow path 315 to the second flow path 328 depends on the selected openings 34C2 to 34F2. The flow rate of the refrigerant can be restricted.

The circular ribs 34C to 34F can be selected to be suitable for ensuring a necessary flow rate of refrigerant depending on the mode in the refrigeration cycle. Further, the circular ribs 34C to 34F have different refrigerant rectifying effects. Therefore, if an abnormal sound occurs when any of the circular ribs 34C to 34F is opposed to the first annular part 316 and the second annular part 329, another circular rib is moved to the first annular part 316 and the second annular part 329. The second gear part 34 can also be rotated so as to face the part 329.

According to the present embodiment, the second flow path 328 side can be set as the refrigerant inflow side (high pressure side), and the first flow path 315 side can be set as the refrigerant outflow side (low pressure side). In this case, in the valve closed position, the circular rib 34B on the low pressure side abuts the first annular portion 316 around the entire circumference. As a result, no refrigerant leakage occurs between the circular rib 34B and the first annular portion 316 even without providing a packing or the like, so that the number of parts can be reduced.

Further, according to the present embodiment, a conversion mechanism for converting rotational motion into linear motion is not provided, and by simply rotating the second gear section 34, the movement between the first channel 315 and the second channel 328 is Since the passage and shutoff of refrigerant can be controlled, it is possible to realize a low-cost electric valve that has a simple and low-profile structure with a small number of parts.

Furthermore, since less driving torque is required, the capacity of the stepping motor can be reduced, thereby saving energy.

(Modified example)
FIG. 5 is a perspective view of the second gear part 44 according to a modification, and the relative position with respect to the second flow path is shown by a dotted line or a chain line. The second gear section 44 can be used in place of the second gear section 34 in the electric valve 1 of the above embodiment. Since the structure other than the second gear part 34 is the same as that of the above embodiment, repeated explanation will be omitted.

The second gear part 44, which is a driven part, includes a cylindrical second shaft 441, a disc-shaped flange part 442 coaxially formed around the second shaft 441, and a disc-shaped flange part 442 formed on the outer periphery of the flange part 442. A driven gear 443 is provided in series. Driven gear 443 meshes with drive gear 332 .

A long hole (through opening) 44A passing through the flange portion 442 is formed to extend in an arc shape around the second axis 441 over an angle of approximately 300 degrees. One end of the elongated hole 44A has a semicircular shape equal to the inner diameter of the second flow path 328, and the width becomes narrower as the distance from the one end increases in the circumferential direction.

As the second gear portion 44 rotates, the elongated hole 44A is displaced relative to the second flow path 328. When the elongated hole 44A is displaced so as to be in a position relative to the second flow path 328 shown by the dotted line, the entire circumference of the second annular portion 329 (see FIG. 3) is attached to the flange portion (here, the shielding wall) 442. By making contact, the flow of refrigerant toward the second flow path 328 is blocked.

On the other hand, when the elongated hole 44A is displaced to a position relative to the second flow path 328 shown by the dashed line, a part of the second flow path 328 is blocked by the flange portion 442, and the cross-sectional area of the flow path is reduced. The flow of refrigerant toward the second flow path 328 is accordingly restricted.

Note that the present invention is not limited to the above-described embodiments. Variations in any of the components of the embodiments described above are possible within the scope of the invention. Moreover, any component can be added or omitted in the embodiments described above.

1 Electric valve 2 Motor part 3 Gear part 31 Case base 315 First flow path 316 First annular part 32 Gear case 328 Second flow path 329 Second annular part 33 First gear part 331 First shaft 332 Drive gear 34, 44 2 gear part 341, 441 2nd shaft 343, 443 Driven gear 342, 442 Flange part 34A to 34F Circular rib 34A1 Opening 34B1 Shielding wall 34C2 First circular opening 34D2 Second circular opening 34E2 Third circular opening 34F2 Fourth circular opening GC gear room

Claims (3)

motor and
a driven part including a flange part and rotationally driven by the motor;
a casing that includes a fluid inflow path on a high pressure side and a fluid discharge path on a low pressure side, and houses the driven part;
The flange portion has a plurality of through openings, a shielding wall, and a circular rib formed around each of the plurality of through openings and the shielding wall, and the flange portion has a plurality of through openings, a shielding wall, and a circular rib formed around each of the through openings and the shielding wall. , any one of the plurality of through openings and the shielding wall is selectively disposed between the inlet channel and the outlet channel,
The plurality of through openings have mutually different numerical apertures and cross-sectional areas, and the smaller the cross-sectional area, the larger the numerical aperture,
An electric valve characterized by: A drive gear is formed on the output shaft of the motor, and the driven part includes a driven gear formed on the outer periphery of the flange and meshed with the drive gear, and a shaft that supports the flange.
The electric valve according to claim 1, characterized in that: A pair of the circular ribs are formed facing each other on both side surfaces of the flange portion, and a pair of annular ribs of the housing are formed facing each other with the flange portion sandwiched therebetween,
When one of the circular ribs contacts the entire circumference of one of the annular portions, a gap is formed between the other of the circular ribs and the other of the annular portions, and the fluid on the inflow path side flows through the gap. supplied to the space accommodating the driven part through the
The electric valve according to claim 1 or 2, characterized in that:

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