Motor-operated valve

Abstract

To prevent increase of hysteresis by preventing wear of a feed screw member.SOLUTION: A motor-operated valve is provided, comprising: a valve body 13 which has inside the same, a valve chest 14 communicating with an inflow channel 15 and an outflow channel 16; a valve element 17 which moves forward and backward relative to a valve seat 23; an electric motor 41 which has a rotor 43 and a stator 42; a speed reduction mechanism 51 which reduces the speed of rotation of the rotor; an output shaft 61 which outputs the rotation reduced by the speed reduction mechanism; and a transmission mechanism 31 which converts the rotational motion of the output shaft into linear motion and transmits it to the valve element. The transmission mechanism includes a feed screw member 33 which has a plate-shaped portion 33b fitted into a slit-shaped fitting groove 61a formed in the output shaft and a male thread portion 33a which constitutes the feed screw, and moves up and down by rotating in response to the rotation of the output shaft, the motor-operated valve further includes rotating bodies (e.g., a pair of round bar members arranged in the fitting groove) 24-27 which are interposed between the fitting groove and the plate-shaped portion and prevent the plate-shaped portion from contacting the inner surface of the fitting groove, rotate as the plate-shaped portion moves up and down, and transmit the rotation of the output shaft to the plate-shaped portion.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a motor-operated valve, and more particularly to a motor-operated valve for controlling the flow rate of a refrigerant in a heating and cooling system or the like. [Background technology]

[0002] Electric valves, which use an electric motor such as a stepping motor to adjust the valve opening and control the flow rate of refrigerant, have traditionally been used in refrigeration cycle equipment equipped with refrigerant circuits, such as air conditioners and refrigeration / freezing equipment.

[0003] An example of such a motor-operated valve is shown in Fig. 6. As shown in the figure, the motor-operated valve includes a valve body 13 having an internal valve chamber 14 communicating with an inflow passage 15 and an outflow passage 16, a valve element 17 that moves toward and away from a valve seat 23 formed in the valve chamber 13, an electric motor 41 having a rotor 43 and a stator 42 that drive the valve element 17, a speed reduction mechanism (paradise planetary gear reduction mechanism) 51 that reduces the speed of rotation of the rotor 43, an output shaft 61 that outputs the rotation reduced by the speed reduction mechanism 51, and a transmission mechanism (feed screw) 31 that converts the rotational motion of the output shaft 61 into linear motion and transmits it to the valve element 17.

[0004] The transmission mechanism 31 includes a feed screw member 33 having a plate-like portion 33b fitted into a slit-like fitting groove 61a formed in an output shaft 61 so as to be movable up and down, and a female screw portion 32a formed on the lower inner surface of the center hole of a bearing member 32. The feed screw member 33 has a male screw portion 33a on its outer circumferential surface that screws into the female screw portion 32a of the bearing member 32, and the female screw portion 32a and the male screw portion 33a form a feed screw 31. Therefore, when the rotation of the output shaft 61 is transmitted to the feed screw member 33 via the plate-like portion 33b, the feed screw member 33 moves up and down while rotating. The vertical movement of the feed screw member 33 is transmitted to the valve body 17 via a ball joint 34.

[0005] Moreover, the following Patent Document 1 is a document disclosing such a motor-operated valve. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2017-9025 A Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, in a conventional motor-operated valve, the rotor 43 (the output shaft 61 connected to the output gear of the reduction mechanism 51) rotates in both directions to control the axial position of the valve body 17 via the feed screw member 33. Also, to enable smooth linear motion of the feed screw member 33, a certain degree of clearance is required between the fitting groove 61a of the output shaft 61 and the plate-shaped portion 33b of the feed screw member 33. For this reason, hysteresis inevitably occurs in the rotation of the output shaft 61 and the rotation of the feed screw member 33 when the rotation direction changes.

[0008] On the other hand, the conventional motor-operated valve is structured such that when the valve is opened and closed, the plate-shaped portion 33b of the feed screw member 33 slides in the fitting groove 61a of the output shaft 61. For this reason, the corners of the plate-shaped portion 33b may wear over time, and this wear increases the hysteresis.

[0009] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to prevent the increase in hysteresis by preventing wear of the feed screw member. [Means for solving the problem]

[0010] In order to solve the above problems and achieve the object, the motor-operated valve according to the present invention includes a valve body having an internal valve chamber communicating with an inflow passage and an outflow passage, a valve element that moves forward and backward relative to a valve seat formed in the valve chamber, an electric motor having a rotor and a stator that drive the valve element, a speed reduction mechanism that reduces the rotation of the rotor and outputs it to an output shaft, and a transmission mechanism that converts the rotational motion of the output shaft into linear motion and transmits it to the valve element. The transmission mechanism also includes a feed screw member that has a male threaded portion that constitutes a feed screw and moves up and down by rotating in response to the rotation of the output shaft. The feed screw member also includes either a plate-shaped portion that is fitted into a slit-shaped fitting groove formed in the output shaft so as to be movable up and down, or a fitting groove into which the plate-shaped portion formed in the output shaft is fitted so as to be movable up and down relative to the plate-shaped portion.

[0011] Furthermore, the electric valve is provided with a rotor that is interposed between the engagement groove and the plate-shaped portion to prevent the plate-shaped portion from contacting the inner surface of the engagement groove, and that rotates on its own axis in response to the relative movement in the upward and downward directions that occurs between the plate-shaped portion and the engagement groove, and transmits the rotation of the output shaft to the feed screw member.

[0012] In the motor-operated valve of the present invention, a rotor is interposed between the plate-shaped portion, which moves relatively in the vertical direction, and the fitting groove, so that the plate-shaped portion does not come into contact with the inner surface of the fitting groove. Therefore, in the motor-operated valve of the present invention, the plate-shaped portion does not slide (moves up and down while contacting the inner surface of the fitting groove) as in the conventional case, so that the plate-shaped portion can be prevented from wearing out and an increase in hysteresis can be avoided. Note that, in the embodiment described later as a typical example of the present invention, the plate-shaped portion is provided on the feed screw member side and the fitting groove is provided on the output shaft side, but in the present invention, the plate-shaped portion may be provided on the output shaft side and the fitting groove may be provided on the feed screw member side.

[0013] Furthermore, the rotating body rotates (spins) in accordance with the up and down movement of the feed screw member (responding to the up and down movement of the plate-like portion or the fitting groove), so that the plate-like portion can be moved up and down smoothly within the fitting groove.

[0014] As a specific structure of the rotating body, there is a first embodiment in which a round bar-shaped member (a bar-shaped member having a circular cross-sectional shape) is used, and a second embodiment in which a spherical member (sphere) is used.

[0015] [First aspect] In a first aspect, the rotating body includes a pair of round bar-shaped members that are disposed in the fitting groove and sandwich the plate-shaped portion so as to enable relative movement in the up-down direction.

[0016] The pair of round bar-like members may include a first member and a second member. In this case, the first member is held in a first retaining hole formed in an inner surface of the fitting groove so as to extend horizontally along one inner surface of the fitting groove, so that the first member is rotatable about its axis and its outer peripheral surface protrudes from the first retaining hole into the fitting groove, and the outer peripheral surface protruding into the fitting groove contacts one side surface of the plate-like member. The second member is held in a second retaining hole formed in an inner surface of the fitting groove so as to extend horizontally along the other inner surface of the fitting groove, so that the second member is rotatable about its axis and its outer peripheral surface protrudes from the second retaining hole into the fitting groove, and the outer peripheral surface protruding into the fitting groove contacts the other side surface of the plate-like member.

[0017] Furthermore, in this first aspect, the pair of round bar-like members may include a third member and a fourth member in addition to the first member and the second member. In this case, the third member is held in a third holding hole formed in an inner surface of the fitting groove so as to extend horizontally along one inner surface of the fitting groove at a position below the first holding hole, so that the third member is rotatable and has an outer circumferential surface protruding from the third holding hole into the fitting groove, and the outer circumferential surface protruding into the fitting groove contacts one side surface of the plate-like portion. The fourth member is held in a fourth holding hole formed in an inner surface of the fitting groove so as to extend horizontally along the other inner surface of the fitting groove at a position below the second holding hole, so that the fourth member is rotatable and has an outer circumferential surface protruding from the fourth holding hole into the fitting groove, and the outer circumferential surface protruding into the fitting groove contacts the other side surface of the plate-like portion.

[0018] In this application, the axial direction of the motor-operated valve and the valve body (in other words, the direction in which the rotary shaft of the rotor or the feed screw member extends, or the direction in which the valve body moves) is referred to as the "vertical direction", one of the vertical directions (the direction from the valve body toward the motor or the rotor) is referred to as the "upper" direction, and the other of the vertical directions (the direction from the motor or the rotor toward the valve body) is referred to as the "lower" direction. Based on the concept of "upper" and "lower", terms related to the upper and lower directions, such as "upper", "lower", "upper" and "lower" are used in this application. However, since the motor-operated valve according to the present invention and the embodiments described below can be used in various orientations (for example, it may be used on its side, i.e., in a position in which the axial direction of the motor-operated valve is perpendicular to the vertical direction (gravity direction)), "lower" does not necessarily mean the direction of gravity and "upper" does not necessarily mean the direction opposite to gravity. Furthermore, the terms "vertical" and "horizontal" are sometimes used, but the vertical direction coincides with the axial direction and the vertical direction, and the direction perpendicular to the vertical direction is the horizontal direction, including the left and right directions.

[0019] [Second aspect] In a second aspect, the rotating body comprises two or more spherical members arranged horizontally and each rotatably held in a retaining hole formed in the plate-shaped portion, and these spherical members are clamped between the opposing inner surfaces of the mating groove so as to be able to rotate on their own axes and move up and down. Effect of the Invention

[0020] According to the present invention, wear of the feed screw member can be prevented, and an increase in hysteresis can be avoided.

[0021] Other objects, features, and advantages of the present invention will become apparent from the following description of the embodiments of the present invention based on the drawings. Note that the present invention is not limited to the following embodiments, and it is obvious to those skilled in the art that various modifications can be made within the scope of the claims. In addition, the same reference numerals in each drawing indicate the same or corresponding parts. [Brief description of the drawings]

[0022] [Figure 1]FIG. 1 is a vertical sectional view showing a motor-operated valve (closed state) according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged view of a main part (part B in FIG. 1) of the motor-operated valve according to the first embodiment. [Diagram 3] FIG. 3 is a vertical sectional view showing the motor-operated valve (in an open state) according to the first embodiment. [Figure 4] FIG. 4 is a view similar to FIG. 2, showing a main part of a motor-operated valve according to a second embodiment of the present invention. [Diagram 5] FIG. 5 is a side view showing a plate-like portion and a rotor in the motor-operated valve according to the second embodiment. [Figure 6] FIG. 6 is a vertical cross-sectional view showing an example of a conventional motor-operated valve (in a closed state). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [First embodiment] As shown in Figures 1 to 3, the motor-operated valve 11 according to the first embodiment of the present invention is an motor-operated valve suitable for use in adjusting the flow rate of refrigerant in a refrigeration cycle device such as a heat pump type heating and cooling system, and has a valve section 12 that controls the flow of refrigerant, an electric motor 41 that drives the valve section 12, a speed reduction mechanism 51 that reduces the rotation of the electric motor 41, and a transmission mechanism (feed screw mechanism) 31 that converts the rotation reduced by the speed reduction mechanism 51 into linear motion and transmits it to the valve section 12 (valve body 17).

[0024] The valve portion 12 comprises: a valve body 13 having a valve chamber 14 therein and formed of a cylindrical member with an open top and bottom (having a top opening and a bottom opening); an inlet pipe (inlet path) 15 joined to the valve body 13 so as to penetrate the side wall of the valve body 13 and communicate with the valve chamber 14; a valve seat member 21 having a central hole 22 passing vertically through the center and having a valve seat 23 on the upper surface of the central hole 22 and joined to the bottom portion of the valve body 13 so as to close the bottom opening of the valve body 13; a valve body 17 supported by a valve body support member 19 and disposed in the valve chamber 14 so as to be movable forward and backward (up and down) relative to the valve seat 23; an outlet pipe (outlet path) 16 fixed to the valve seat member 21 so as to communicate with the valve chamber 14 via the central hole 22 of the valve seat member 21; and a connecting member 18 joined to the top portion of the valve body 13 so as to close the top opening of the valve body 13, in order to install an electric motor 41 in the valve portion 12.

[0025] In this embodiment, a stepping motor is used as the electric motor 41 that drives the valve body 17. This stepping motor 41 is composed of a stator 42 installed on the outside (outer periphery) of a cylindrical can (sealed container) 39 with no bottom and a lid (the bottom is open and the top is closed) that is fixed to the connecting member 18 so as to cover the upper surface of the connecting member 18, and a rotor 43 installed inside (inner periphery) of the can 39 so as to be rotatable.

[0026] The stator 42 includes a yoke 44, a coil 46 formed by winding a wire around a bobbin 45, and a resin molded cover 47 that covers the yoke 44 and the coil 46. On the other hand, the rotor 43 is configured by integrally connecting a cylindrical rotor member 48 made of a magnetic material and a sun gear member 52 made of a resin material. A shaft 50 is inserted into the center of the sun gear member 52, and the upper part of the shaft 50 is supported by a support member 49 arranged inside the top of the can 39.

[0027] The sun gear 53 of the sun gear member 52 meshes with a plurality of planetary gears 54 rotatably supported on a shaft 55 provided on a carrier 56 placed on the bottom surface of the output gear 59. The upper part of the planetary gear 54 meshes with an annular ring gear (internal tooth fixed gear) 58 attached to the upper part of a cylindrical member 40 fixed to the upper part of the valve body support member 19, and the lower part of the planetary gear 54 meshes with an internal tooth gear 57 of an annular output gear 59. The number of teeth of the ring gear 58 and the number of teeth of the internal tooth gear 57 of the output gear 59 are slightly different, so that the rotation speed of the sun gear 53 is reduced at a large reduction ratio and transmitted to the output gear 59. These gear mechanisms (sun gear 53, planetary gear 54, ring gear 58 and output gear 59) constitute a reduction mechanism (paradise planetary gear reduction mechanism) 51 that reduces the rotation speed of the electric motor 41 described above.

[0028] The connecting member 18 joined to the upper surface of the valve body 13 is a ring-shaped member with a through hole in the center, into which a valve body support member 19 that supports the valve body 17 is fitted. The valve body support member 19 has a valve body support member main body 19a in the shape of a cylindrical container with a bottom and no lid, and a cylindrical cylinder portion 19c that hangs down vertically downward from the underside of a bottom plate portion 19b of the valve body support member main body 19a. The valve body support member main body 19a supports the valve body upper portion 17b that penetrates the bottom plate portion 19b so that it can slide in the vertical direction. The cylinder portion 19c supports the valve body lower portion 17a (the upper portion of the valve body lower portion 17a) so that it can slide in the vertical direction.

[0029] A cylindrical bearing member 32 is fitted into the upper part of the valve body support member 19, and the upper surface of the valve body support member 19 is crimped to fix the bearing member 32. An output gear 59 is in slidable contact with the upper surface of the bearing member 32. The upper part of a stepped cylindrical output shaft 61 is press-fitted into the center of the bottom of the output gear 59, and the lower part of the output shaft 61 is rotatably inserted into a fitting hole 32b formed in the center of the upper surface of the bearing member 32. The lower end of the shaft 50 is rotatably fitted into the upper part of the output shaft 61.

[0030] A female threaded portion 32a is formed at the lower center portion of the bearing member 32, and a male threaded portion 33a formed on the outer circumferential surface of the feed screw member 33 is screwed into this female threaded portion 32a. The feed screw mechanism 31 consisting of the bearing member 32 (female threaded portion 32a) and the feed screw member 33 (male threaded portion 33a) constitutes a transmission mechanism that converts the rotational motion supplied from the stepping motor 41 via the reduction gear mechanism 51 into linear motion in the vertical direction and transmits it to the valve body 17.

[0031] Here, the output gear 59 rotates at a constant position in the vertical direction without moving up and down, and a flat plate-like portion 33b provided at the upper end of the feed screw member 33 is inserted into a slit-like fitting groove 61a provided at the lower end of the output shaft 61 connected to the output gear 59, thereby transmitting the rotational motion of the output gear 59 to the feed screw member 33. That is, when the plate-like portion 33b provided on the feed screw member 33 moves up and down within the fitting groove 61a of the output shaft 61, the output gear 59 (rotor 43) rotates, and thus the feed screw member 33 moves linearly up and down by the feed screw mechanism 31, even though the output gear 59 and the output shaft 61 do not move up and down.

[0032] In this embodiment, the fitting groove 61a is provided with round bar members (rod-shaped members with a circular cross section) 24, 25; 26, 27 as the rotating body referred to in the present invention. More specifically, two pairs of round bar members (an upper pair of round bar members 24, 25 and a lower pair of round bar members 26, 27) are provided vertically so as to sandwich the plate-shaped portion 33b of the feed screw member 33 inserted into the fitting groove 61a, totaling four round bar members 24-27. Each of the round bar members 24-27 extends horizontally in the front-rear direction (direction perpendicular to the paper surface of FIGS. 1-3) in the rotation position (rotation state) of the output shaft 61 shown in FIGS. 1-3, and is rotatably (rotatably) inserted into a holding hole 28 drilled in the inner surface of the fitting groove 61a so as to extend horizontally in the same manner.

[0033] Each retaining hole 28 is formed so that a slit-like opening communicating with the inside of the fitting groove 61a is formed on the inside (the side closer to the center of the fitting groove 61a), and the outer circumferential surface of each round bar member 24-27 protrudes inward (the side closer to the center of the fitting groove 61a) from the inner surface of the fitting groove 61a through the slit-like opening, thereby contacting the surface of the plate-like portion 33b. Note that the thickness of the plate-like portion 33b is smaller than the width of the fitting groove 61a (the distance between the inner surfaces of the opposing fitting grooves 61a), and both the left and right surfaces of the plate-like portion 33b are not in contact with the inner surface of the fitting groove 61a (i.e., a certain gap S is formed between the inner surface of the fitting groove 61a).

[0034] Furthermore, when the plate-shaped portion 33b moves up and down, each of the round bar members 24-27 rotates (spins) within each holding hole 28. As a result, the plate-shaped portion 33b moves smoothly up and down within the fitting groove 61a while being sandwiched between the round bar members 24-27 without coming into contact with the inner surface of the fitting groove 61a. Furthermore, the rotation of the output shaft 61 is transmitted to the feed screw member 33 (plate-shaped portion 33b) via the round bar members 24-27, and at the same time, it is possible to prevent the plate-shaped portion 33b from rubbing against the inner surface of the fitting groove 61a and becoming worn, and it is possible to avoid an increase in hysteresis due to long-term use.

[0035] In this embodiment, two pairs of round bar members 24-27 are provided, but only one pair (upper pair of round bar members 24, 25 or lower pair of round bar members 26, 27) may be provided. The advantage of providing two pairs as in this embodiment is that the plate-shaped portion 33b is guided by the two pairs of round bar members 24-27 arranged at a certain interval in the vertical direction, so that the feed screw member 33 can be stably moved vertically in a straight line. On the other hand, the advantage of providing one pair of round bar members (upper round bar members 24, 25 or lower round bar members 26, 27) as described above is that the relative axial wobble (rocking of the plate-shaped portion 33b) of the feed screw member 33 with respect to the output shaft 61 can be absorbed. That is, as described later, the feed screw member 33 is connected to the valve body 17 by the ball joint 34 (ball 35) so as to be rotatable relative to the valve body 17, but since the connection is via the ball 35 of the ball joint 34, the feed screw member 33 can also rock. Here, if the pair of round bar members 24-27 that clamps the plate-shaped portion 33b as described above is either the upper round bar members 24, 25 or the lower round bar members 26, 27, any oscillation of the feed screw member 33 can be absorbed.

[0036] The linear motion of the feed screw member 33 is transmitted to the valve element 17 via a ball joint 34 consisting of a ball 35 and a ball seat 36 fitted into a fitting hole 17d provided in the center of the upper surface of the valve element upper part 17b. The valve element 17 is composed of a valve element upper part 17b penetrating the bottom plate part 19b of the valve element support member main body 19a, and a valve element lower part 17a arranged in the cylinder part 19c and the valve chamber 14. The valve element upper part 17b penetrates the bottom plate part 19b of the valve element support member main body 19a and also penetrates the bottom plate part 37a of the spring receiving member 37 arranged on the inner bottom surface of the valve element support member main body 19a, and has a head part 17c with an expanded diameter like a flange at its upper end.

[0037] The spring receiving member 37 has a bottom plate portion 37a that allows the valve body upper portion 17b to penetrate and abuts against the lower peripheral edge portion of the head portion 17c from below, a cylindrical peripheral wall portion 37c that forms a ring-shaped gap between the inner peripheral surface of the valve body support member main body 19a, and a flange portion 37b that horizontally spreads outward from the upper end of the peripheral wall portion 37c. A compression coil spring 38 is provided between the flange portion 37b of the spring receiving member 37 and the bottom plate portion 19b of the valve body support member main body 19a. This compression coil spring 38 constantly urges the valve body 17 (the head portion 17c of the valve body upper portion 17b) upward via the bottom plate portion 37a of the spring receiving member 37. As a result, even when the feed screw member 33 moves upward, the feed screw member 33 and the valve body 17 that are in contact with each other via the ball joint 34 do not separate, and the feed screw member 33 and the valve body 17 are integrated in the vertical direction.

[0038] The feed screw member 33 on the drive section side rotates and slides about the central axis A relative to the valve disc 17 via balls 35, and the rotation of the feed screw member 33 is not transmitted to the valve disc 17. In the motor-operated valve 11 of this embodiment, the valve body 13, valve seat member 21, valve seat 23, valve disc 17, valve disc support member 19, feed screw member 33, output shaft 61, shaft 50, rotor 43, and other members are coaxially arranged, and the central axis A of these members coincides with the rotation axis of the rotor 43.

[0039] The operation of the motor-operated valve 11 according to this embodiment will be described as follows.

[0040] When a current is supplied to the stator 42 (coil 46) so that the rotor 43 rotates in one direction from the closed valve state shown in Fig. 1, the rotation of the rotor 43 is converted into linear motion by the feed screw mechanism 31, and the feed screw member 33 is pulled upward. As a result, the valve body 17 (head part 17c of the valve body upper part 17b) pressed against the lower surface of the feed screw member 33 via the ball joint 34 by the urging force of the compression coil spring 38 is pulled upward, and the valve body 17 (valve body lower part 17a) is separated from the valve seat 23, and the refrigerant that has flowed in from the inlet pipe 15 flows through the valve chamber 14 and the through hole 22 and flows out from the outlet pipe 16 (see Fig. 3). The amount of refrigerant passing through in this open valve state (refrigerant flow rate) can be adjusted by the amount of rotation of the rotor 43 (the distance between the valve seat 23 and the valve body 17).

[0041] On the other hand, when a current is supplied to the stator 42 (coil 46) so that the rotor 43 rotates in the opposite direction from the open valve state, the rotation of the rotor 43 is converted into linear motion by the feed screw mechanism 31, and the feed screw member 33 moves downward. With this downward movement, the valve body 17 moves downward, and when the valve body 17 (valve body lower part 17a) abuts against the valve seat 23, the flow path between the inlet pipe 15 and the outlet pipe 16 is blocked, and the valve is closed (see FIG. 1).

[0042] In the above operation description, the refrigerant flows in through the inlet pipe 15 and flows out through the outlet pipe 16. However, it is also possible to use the motor-operated valve 11 in the opposite manner, so that the refrigerant flows in through the outlet pipe 16 and flows out through the inlet pipe 15.

[0043] Second Embodiment A motor-operated valve according to a second embodiment of the present invention will be described with reference to Figures 4 and 5. Note that the same components as those in the motor-operated valve of the first embodiment will be denoted by the same reference numerals, and duplicated descriptions will be omitted, with differences being mainly described.

[0044] As shown in Figures 4 and 5, the motor-operated valve according to the second embodiment of the present invention has a spherical member 29 as the rotating body referred to in the present invention instead of the round bar member of the first embodiment, and the other configurations are similar to those of the first embodiment.

[0045] Specifically, in this embodiment, through holes are drilled horizontally through the plate-like portion 33b of the feed screw member 33 in the thickness direction, and these serve as holding holes 30 for holding the spherical members 29. A plurality of holding holes 30 (for example, two) are formed so as to be arranged in the width direction of the plate-like portion 33b (see FIG. 5), and the spherical members 29 are disposed in each holding hole 30 so as to be rotatable (rotatable on their own axis). Each spherical member 29 is sandwiched between the opposing inner surfaces of the fitting groove 61a so as to be movable up and down together with the plate-like portion 33b.

[0046] This connection structure between the output shaft 61 (engagement groove 61a) and the feed screw member 33 (plate-shaped portion 33b) via the spherical member 29 also makes it possible to transmit the rotation of the output shaft 61 to the feed screw member 33 while preventing wear associated with the up and down movement of the plate-shaped portion 33b. [Explanation of symbols]

[0047] A center axis S Gap 11 Motor-operated valve 12 Valve section 13 Valve body 14 Valve chamber 15 Inflow pipe 16 Outflow pipe 17 Valve body 17a Lower part of valve body 17b Upper part of valve body 17c Head 17d Mating hole 18 Connecting members 19 Valve body support member 19a Valve body support member body 19b Bottom plate part 19c Cylinder section 21 Valve seat material 22 Central hole of valve seat member 23 Valve seat 24, 25, 26, 27 Round bar members 28,30 retaining hole 29 Spherical Members 31 Transmission mechanism (feed screw mechanism) 32 Bearing materials 32a Female thread 32b insertion hole 33 Lead screw member 33a Male thread 33b Plate-shaped part 34 Ball joint 35 Ball 36 Ball seat 37 Spring support member 37a Bottom plate part 37b Flange part 37c Peripheral wall part 38 Compression coil spring 39 Can 40 Cylindrical member 41 Electric motor 42 Stator 43 Rotor 44 York 45 Bobbin 46 Coil 47 Resin molded cover 48 Rotor parts 49 Support member 50 Shaft 51 Reduction mechanism 52 Sun gear parts 53 Sun Gear 54 Planetary Gear 55 Shaft 56 Career 57 Internal gear 58 Ring gear 59 Output gear 61 Output shaft 61a Fitting groove

Claims

1. a valve body having an internal valve chamber communicating with an inlet passage and an outlet passage; a valve body that moves toward and away from a valve seat formed in the valve chamber; an electric motor having a rotor and a stator for driving the valve body; a reduction mechanism that reduces the rotation speed of the rotor and outputs the reduced speed to an output shaft; a transmission mechanism that converts the rotational motion of the output shaft into a linear motion and transmits the linear motion to the valve body; Equipped with The transmission mechanism includes: A feed screw member having a male threaded portion that constitutes a feed screw and that moves up and down by rotating in response to the rotation of the output shaft. having The feed screw member further has either a plate-shaped portion fitted into a slit-shaped fitting groove formed in the output shaft so as to be movable up and down, or a fitting groove into which the plate-shaped portion formed in the output shaft is fitted so as to be movable relative to the output shaft in the up and down direction. A motor-operated valve, a rotor that is interposed between the fitting groove and the plate-shaped portion to prevent the plate-shaped portion from contacting the inner surface of the fitting groove, and that rotates in response to a relative movement in the up-down direction between the plate-shaped portion and the fitting groove, and transmits the rotation of the output shaft to the feed screw member; A motor-operated valve comprising:

2. The rotating body includes a pair of round bar-shaped members that are arranged in the fitting groove and sandwich the plate-shaped portion so as to be capable of relative movement in the vertical direction. The motor-operated valve according to claim 1.

3. The pair of round bar-shaped members includes a first member and a second member, the first member is held in a first retaining hole formed in an inner surface portion of the fitting groove so as to extend horizontally along one inner surface of the fitting groove, so as to be rotatable about its axis and so as to have an outer peripheral surface protruding from the first retaining hole into the fitting groove, and the outer peripheral surface protruding into the fitting groove contacts one side surface of the plate-shaped portion; The second member is held in a second holding hole formed on the inner surface of the fitting groove so as to extend horizontally along the other inner surface of the fitting groove, so as to be rotatable about its axis and so as to have an outer peripheral surface protruding from the second holding hole into the fitting groove, and the outer peripheral surface protruding into the fitting groove is in contact with the other side surface of the plate-shaped portion. The motor-operated valve according to claim 2.

4. The pair of round bar-shaped members further includes a third member and a fourth member, the third member is held in a third retaining hole formed in an inner surface portion of the fitting groove so as to extend horizontally along one inner surface of the fitting groove at a position below the first retaining hole, so that the third member is rotatable about its axis and has an outer peripheral surface protruding from the third retaining hole into the fitting groove, and the outer peripheral surface protruding into the fitting groove contacts one side surface of the plate-shaped portion; The fourth member is held in a fourth retaining hole formed in the inner surface of the fitting groove so as to extend horizontally along the other inner surface of the fitting groove at a position lower than the second retaining hole, so that the fourth member can rotate about its own axis and has an outer circumferential surface protruding from the fourth retaining hole into the fitting groove, and the outer circumferential surface protruding into the fitting groove is in contact with the other side surface of the plate-shaped portion. The motor-operated valve according to claim 3.

5. The rotating body includes two or more spherical members arranged in a horizontal direction and rotatably held in holding holes formed in the plate-like portion, These spherical members are sandwiched between the opposing inner surfaces of the fitting groove so as to be capable of rotation and relative movement in the up-down direction. The motor-operated valve according to claim 1.

Images