JP2019124315A - Motor-operated valve - Google Patents

Abstract

To provide a motor-operated valve that can reliably reduce slide resistance at the time of rotor rotation without making any significant change for conventional motor-operated valves.SOLUTION: In a motor-operated valve, a support member 61 for supporting a rotor 50 so as to be rotatable inside a can 30 is press-fitted into the can 30 and fixed to the can. The support member 61 is arranged while having a clearance to a sun gear member 52 of the rotor 50.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor-operated valve, for example, to a motor-operated valve that controls the flow rate of fluid (refrigerant) in an air conditioning system or the like.

  A conventional example of this type of motor-operated valve is shown in FIG. The motor-operated valve 1 'of the illustrated conventional example basically includes a valve body 10 having a valve chamber 14 and a valve seat 15 formed therein, and a cylinder with a ceiling fixed to the valve body 10 via a base plate 31. A stepping motor 63 comprising a can 30 having a shape, a stator 40 provided outside the can 30 and a rotor 50 provided inside the can 30, a planetary gear reduction mechanism 60 for reducing the rotational speed of the rotor 50; The rotational movement of the valve body 21 for controlling the passing amount of fluid by contacting and separating the valve seat 15 and the output gear 57 of the planetary gear reduction mechanism 60 is converted to linear movement via the screw feed mechanism 27 to drive the valve body 21 And a screw drive member 22.

  The valve body 10 is formed with a valve port 16 communicating with the valve chamber 14, and the pipe 11 is connected to the valve port 16 side, and the pipe 12 is communicated with an opening formed on the side surface of the valve chamber 14. Is connected. Further, a screw bearing member 13 having a female screw portion 13a formed in the lower half of the central portion is inserted into the upper portion of the valve chamber 14 of the valve main body 10 and fixed to the valve main body 10 by caulking (crimped portion 17) .

  The stator 40 fitted to the outer peripheral portion of the can 30 comprises a yoke 41, a bobbin 42, a coil 43, a resin mold 44 and the like, and is rotatably supported within the can 30 (without moving up and down). A cylindrical rotor member 51 made of a magnetic material and a sun gear member (also called a pinion gear) 52 made of a resin material are integrally connected. A shaft 62 is inserted into the central portion of the sun gear member 52, and the upper portion of the shaft 62 is supported by a support member 61 disposed inside the top of the can 30.

  The sun gear 53 of the sun gear member 52 meshes with a plurality of planet gears 55 rotatably supported by a shaft 56 provided on a carrier 54 mounted on the bottom surface of the output gear 57. The upper half of the planetary gear 55 meshes with an annular ring gear (internal gear fixed gear) 58 attached by caulking to the upper portion of the cylindrical member 18 fixed to the upper portion of the valve body 10, and the lower half of the planetary gear 55 is annular The internal gear 57a of the output gear 57 of FIG. The number of teeth of the ring gear 58 and the number of teeth of the internal gear 57a of the output gear 57 are slightly different, whereby the rotational speed of the sun gear 53 is reduced at a large reduction ratio and transmitted to the output gear 57. (A gear arrangement such as this is called a so-called strange planetary gear reduction mechanism 60).

  The output gear 57 is in sliding contact with the upper surface of the screw bearing member 13. The upper portion of the stepped cylindrical output shaft 59 is press-fitted in the center of the bottom of the output gear 57, and the lower portion of the output shaft 59 is a screw bearing. It is rotatably inserted into the insertion hole 13 b formed in the upper half of the central portion of the member 13. The lower portion of the shaft 62 is fitted to the upper portion of the output shaft 59.

  An external thread 22a of a screw drive member (also referred to as a driver) 22 is screwed into the internal thread 13a of the screw bearing member 13. The screw drive member 22 is used to rotate the output gear 57 (that is, the rotor 50). Is converted into linear movement (raising and lowering movement) in the direction of the axis O (raising and lowering direction) by the screw feed mechanism 27 including the male screw 22a and the female screw 13a. Here, the output gear 57 is rotating without moving up and down at a fixed position in the direction of the axis O, and is screwed into a slit-like fitting groove 59b provided at the lower end of the output shaft 59 connected to the output gear 57. A flat driver-shaped plate-like portion 22b provided at the upper end of the drive member 22 is inserted to transmit the rotational movement of the output gear 57 to the screw drive member 22 side. When the plate-like portion 22b provided on the screw drive member 22 slides in the direction of the axis O within the fitting groove 59b of the output shaft 59, if the output gear 57 (rotor 50) rotates, the output gear 57 rotates The screw drive member 22 linearly moves in the direction of the axis O by the screw feed mechanism 27 despite the fact that it does not move in the axial direction. The linear motion of the screw drive member 22 is transmitted to the shaft-like valve body 21 through the ball-like joint 25 consisting of the ball 23 and the ball receiving seat 24, and the valve body 21 is fixed to the inside of the valve body 10 It is guided by the cylindrical cylindrical spring case 19 and moved in the direction of the axis O. Further, a compression coil spring 26 is compressed between the spring case 19 and the valve body 21 to normally bias the valve body 21 in the valve opening direction.

  With this configuration, the flow passage area (valve opening degree) between the valve body 21 and the valve seat 15 changes, and the flow rate of the refrigerant passing through the valve port 16 can be controlled (for example, Patent Document 1 below) reference).

  Further, as the motor-operated valve of this type, the output gear 57 is integrally connected to the screw drive member (driver) 22, and the output gear 57 and the screw drive member 22 integrally rotate and move in the direction of the axis O (lifting). At the same time, the carrier 53 and the planetary gear 55 mounted on the bottom surface of the output gear 57 are also raised and lowered according to the elevation of the output gear 57, while the ring gear 58 is a ring between the ring gear 58 and the sun gear member 52. It is already known that a disc spring is supported by 58 to constantly push the sun gear member 52 toward the support member 61 side of the shaft 62 and abut against the support member 61 (for example, the following patent documents) 2).

JP, 2017-009025, A JP, 2016-106205, A

  By the way, in the conventional motor-operated valve as described above, the support member for supporting the upper portion of the shaft inserted into the rotor is formed to have the same diameter as the inner diameter of the can, and is extrapolated to the upper portion of the shaft. It is placed on the upper surface of the gear member and disposed inside the can, thereby positioning (in the radial direction) the rotor (a shaft inserted into the rotor).

  Therefore, in the conventional motor-operated valve as described above, when the rotor rotates, (the upper surface of) the sun gear member of the rotor and (the lower surface of) the support member relatively rotate (slide) and the rotor rotates There is a concern that the sliding resistance of the

  The present invention has been made in view of the above circumstances, and an object thereof is to reliably reduce the sliding resistance at the time of rotor rotation without making a major change to the conventional motorized valve. Providing a motorized valve that can

  In order to solve the above problems, the motor-operated valve according to the present invention basically includes a valve body having a valve chamber and a valve seat, a valve body disposed so as to be able to move up and down in the valve chamber, and the valve body. A motor having a fixed can, a stator mounted outside the can, and a rotor rotatably mounted inside the can, and a support member rotatably supporting the rotor inside the can And a screw feed mechanism for converting the rotational movement of the rotor to the vertical movement of the valve body, wherein the support member is press-fitted and fixed to the can.

  In a preferred embodiment, the support member is located on the upper side of the rotor and supports the upper portion of a shaft inserted in the center of the rotor.

  In a further preferred aspect, the lower portion of the shaft is supported by a screw bearing member fixed to the valve body and formed with an internal thread forming one of the screw feed mechanisms.

  In another preferred embodiment, the support member is disposed with a gap from the rotor.

  In another preferred embodiment, the support member is made of resin.

In another preferred embodiment, the fitting margin between the support member and the can is 0.1 mm or less, and the linear expansion coefficient of the support member is 60 × 10 ⁻⁶ / ° C. or less.

  In another preferred aspect, the rotor is adapted to rotate without moving up and down.

  According to the present invention, since the support member that rotatably supports the rotor inside the can is press-fit and fixed to the can, sliding between the rotor and the support member can be suppressed. As compared with the conventional one placed on the sun gear member and disposed inside the can, the sliding resistance at the time of the rotor rotation can be reliably reduced, so that the rotation (that is, the raising and lowering of the valve body) The required driving torque can be reduced, and the physique can be miniaturized.

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows one Embodiment of the motor operated valve which concerns on this invention. The principal part expansion longitudinal cross-sectional view explaining the attachment method of the supporting member with respect to a can. The figure which shows the relationship between ambient temperature and a fitting margin by material difference. The longitudinal cross-sectional view which shows the conventional motor operated valve.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a motor-operated valve according to the present invention. Moreover, FIG. 2 is a principal part enlarged longitudinal cross-sectional view explaining the attachment method of the supporting member with respect to a can.

  In each drawing, the gap formed between the members, the separation distance between the members, and the like may be drawn in an exaggerated manner for easy understanding of the invention and for convenience of drawing. is there.

  In the motor-operated valve of the present embodiment shown below, the parts corresponding to the respective parts of the motor-operated valve 1 'of the conventional example shown in FIG. In the following, differences will be mainly described.

  The basic configuration of the motor-operated valve 1 of this embodiment is substantially the same as that of the motor-driven valve 1 'of the prior art shown in FIG. 4, but mainly the valve body 10 having the valve chamber 14 and the valve seat 15; A valve body 21 disposed so as to be movable up and down 14; a cylindrical can 30 with a ceiling fixed to the valve body 10 via a base plate 31; and a stator 40 and a can 30 provided outside the can 30. The rotational movement of the output gear 57 of the planetary gear reduction mechanism 60, the stepping motor 63 comprising the rotor 50 rotatably mounted therein, the planetary gear reduction mechanism 60 for reducing the rotational speed of the rotor 50, and the straight line of the valve 21 And a screw feed mechanism 27 for converting the movement (lifting movement).

  The screw feed mechanism 27 is formed on the outer periphery of the screw drive member 22 and the female screw portion 13a formed on the inner periphery of the screw bearing member 13 fixed to the upper portion of the valve chamber 14 of the valve main body 10 as described above. And an externally threaded portion 22a.

  In the motor-operated valve 1 ′ of the conventional example described above, the support member 61 for supporting the upper portion of the shaft 62 inserted in the central portion of the sun gear member 52 constituting the rotor 50 is extrapolated to the upper portion of the shaft 62. The sun gear member 52 is placed on the upper surface of the sun gear member 52 and disposed inside the can 30.

  On the other hand, in the motor-operated valve 1 of the present embodiment, the support member 61 is press-fitted inside the top of the can 30 and fixed (relative movement impossible and relative rotation impossible).

  Specifically, the support member 61 is formed of, for example, a thick-walled disk made of a resin material, and is set to be slightly larger than the inner diameter of the can 30 in the state before assembly. It is press-fitted inside the top of a sheet metal can 30 so as to slightly squeeze the press-fit margin) and fixed in place (see FIG. 2). The rotor 50 is disposed below the support member 61 by inserting (rotatably) the upper portion of the shaft 62 in a through hole 61 a provided in the central portion of the support member 61. At that time, the support member 61 is arranged and fixed on the upper side of the rotor 50 with a predetermined gap G (floating) from (the sun gear member 52 of) the rotor 50. In order to facilitate positioning of the support member 61, the support member 61 may be disposed in contact with the ceiling of the can 30.

  Further, the lower portion of the shaft 62 inserted in the rotor 50 is press-fit into the center of the bottom portion of the output gear 57 by the screw bearing member 13 fixed to the valve body 10, and the lower portion is the valve body 10 The screw bearing member 13 is supported by being fitted into the upper portion of the output shaft 59 rotatably inserted into the insertion hole 13b formed in the upper half of the central portion of the screw bearing member 13 fixed to the shaft.

  The output shaft 59 and the screw drive member 22 can be made of metal such as SUS, ceramic, glass or the like. Further, in this example, the output shaft 59 is press-fit into the output gear 57, but the output gear 57 and the output shaft 59 may be configured as one component by insert molding.

  With this configuration, the rotor 50 is rotatably supported inside the can 30 without the upper surface of the sun gear member 52 sliding on the lower surface of the support member 61.

As described above, when the support member 61 made of resin is press-fitted and fixed to the inside of the can 30 made of sheet metal, in order to prevent abrasion of the support member 61 at the time of assembly and deformation of the can 30, etc. For example, the ambient temperature is about 20 ° C.) The fitting margin is preferably 0.1 mm or less (see FIGS. 2 and 3). At the same time, in consideration of the use conditions (at least -30 ° C) in the refrigeration cycle, in order to secure the fitting margin at the lowest temperature (-30 ° C) including the general interference fit tolerance width, the support member 61 It is further preferable to use a material having a linear expansion coefficient (linear expansion coefficient) of 60 × 10 ⁻⁶ / ° C. or less (see FIG. 3). In addition, as illustrated in FIG. 3, when a material having a linear expansion coefficient (linear expansion coefficient) of 100 × 10 ⁻⁶ / ° C. is used, the minimum temperature (−30 ° C.) in consideration of a general interference fit tolerance width It will not be possible to secure the fitting allowance at As a resin material that can satisfy such conditions, for example, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), etc. can be adopted.

  Also in the motor-operated valve 1 of this embodiment having such a configuration, the flow passage area (valve opening degree) between the valve body 21 and the valve seat 15 changes as in the motor-operated valve 1 'of the conventional example described above. The flow rate of the refrigerant passing through the port 16 can be controlled.

  As described above, in the motor-operated valve 1 according to the present embodiment, the support member 61 rotatably supporting the rotor 50 in the can 30 is press-fitted and fixed to the can 30, so that the slide between the rotor 50 and the support member 61 Since the movement can be suppressed, for example, the sliding resistance at the time of rotor rotation can be reliably reduced as compared with the conventional one in which the support member is placed on the sun gear member of the rotor and disposed inside the can. As a result, the drive torque required for rotation (that is, raising and lowering of the valve body) can be reduced, and downsizing of the physique can be achieved.

  The present invention is not limited to a type in which the poppet-type or piston-type valve body is seated at the valve seat and the flow of fluid is blocked when the poppet-type or piston-type valve body is at the lowest position. It goes without saying that it can be adopted for various types of motorized valves. For example, when the valve body is at the highest position, the valve body is seated on a valve seat provided on the back side of the valve port to shut off the flow of fluid (in this case, the valve shaft and A compression coil spring may be interposed between the valve body and the valve body to bias the valve in the valve closing direction. In addition, even if the valve body is seated on the valve seat, the motor-operated valve of a type in which the passing flow rate of the predetermined amount is secured via the communication hole provided in the valve body or the bleed groove provided in the valve seat. When the valve body is in the fully lowered position (usually fully closed), a gap of a predetermined size is formed between the valve body and the valve seat to ensure a predetermined amount of passing flow rate. It may be a closed valveless type motorized valve.

  Further, in the above embodiment, at the time of driving, the rotor 50 (the output shaft 59) rotates without moving up and down, and the plate-like portion 22b protrudingly provided on the screw drive member 22 is an axis in the fitting groove 59b of the output shaft 59. By sliding in the O direction (raising and lowering direction), the screw drive member 22 (valve body 21) linearly moves in the raising and lowering direction with respect to the valve main body 10 and the like. It is needless to say that it can be adopted for the motor-operated valve of the type that moves up and down while rotating. In the above embodiment, the fitting groove 59b is provided on the output shaft 59 connected to the output gear 57, and the plate-like portion 22b is provided on the screw drive member 22. Conversely, the plate-like portion on the output shaft 59 Of course, the screw drive member 22 may be provided with a fitting groove.

DESCRIPTION OF SYMBOLS 1 motor-operated valve 10 valve main body 13 screw bearing member 13a female screw part 14 valve chamber 15 valve seat 16 valve port 18 cylindrical member 19 spring case 21 valve body 22 screw drive member 22a male screw 22b plate-like part 26 compression coil spring 27 screw feeding mechanism Reference Signs List 30 can 31 base plate 40 stator 50 rotor 51 rotor member 52 sun gear member 57 output gear 59 output shaft 59 b fitting groove 60 wonder planetary gear reduction mechanism 61 support member 62 shaft 63 stepping motor

Claims (7)

A valve body having a valve chamber and a valve seat;
A valve body disposed movably up and down in the valve chamber;
A can fixed to the valve body,
A motor having a stator mounted on the exterior of the can and a rotor rotatably mounted on the interior of the can;
A support member rotatably supporting the rotor inside the can;
A screw feed mechanism for converting the rotational movement of the rotor to the vertical movement of the valve body,
The motor-operated valve, wherein the support member is press-fitted and fixed to the can.   The motor-operated valve according to claim 1, wherein the support member is positioned above the rotor and supports an upper portion of a shaft inserted in a central portion of the rotor.   The motor-operated valve according to claim 2, wherein a lower portion of the shaft is supported by a screw bearing member fixed to the valve main body and having an internal thread portion forming one of the screw feed mechanisms.   The motor-operated valve according to any one of claims 1 to 3, wherein the support member is disposed with a gap from the rotor.   The motor-operated valve according to any one of claims 1 to 4, wherein the support member is made of resin. The fitting margin of the said supporting member and the said can is 0.1 mm or less, The linear expansion coefficient of the said supporting member is 60 * 10 < ^-6 > / degrees C or less, Any one of Claim 1 to 5 characterized by the above-mentioned. The motor operated valve according to one item.   The motor-operated valve according to any one of claims 1 to 6, wherein the rotor is configured to rotate without moving up and down.

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