JP7550466B2 - Motor-operated valve - Google Patents

Description

The present invention relates to a motor-operated valve.

Conventionally, motorized valves are installed, for example, in the middle of a fluid piping system and are used to open and close the fluid flow path and control the flow rate (see Patent Document 1). In such motorized valves, the valve body is opened and closed by a stepping motor attached to the valve body, achieving precise flow rate control and sealing when the valve is closed.

JP 2019-143704 A

The fluid (refrigerant) flowing through the refrigeration cycle contains relatively hard foreign matter (metal powder, shavings, abrasives, sludge, etc.). Most of the foreign matter is captured by strainers installed in the path, but some of the fine foreign matter enters the motor-operated valve along with the fluid and passes between the valve body and the valve seat when the valve is opened.

If such a foreign object passes between the valve disc and the valve seat while the valve is closing, the foreign object may become trapped between the valve disc and the valve seat (known as foreign object entrapment), causing deformation of the valve seat or valve disc, which may result in fluid leakage even when the valve disc is in a completely closed position.

In particular, in motor-operated valves equipped with a gear-type reduction mechanism with a high reduction ratio, the rotational speed of the stepping motor is reduced and converted into axial movement of the valve disc, which causes excessive surface pressure between the valve disc and the valve seat when the valve is closed. Therefore, if a foreign object becomes caught between the valve disc and the valve seat, it is pressed strongly against the valve disc or the valve seat, which causes scratches, dents, or other depressions on the contact surfaces of the valve seat or valve disc, making fluid leakage even more likely to occur.

The present invention was made in consideration of these problems, and aims to provide an electrically operated valve that is less likely to cause foreign matter to become caught between the valve body and the valve seat.

The motor-operated valve of the present invention comprises:
A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction ,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of contacting the stopper portion after the valve body is seated on the valve seat,
the locking member is a sleeve member that is connected to the intermediate shaft and fits onto an outer periphery of the valve body,
the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
The sleeve member has a communication hole that communicates the intermediate chamber with a valve chamber in the valve body via a gap between the sleeve member and the valve body .
The motor-operated valve of the present invention comprises:
A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of contacting the stopper portion after the valve body is seated on the valve seat,
the locking member is a sleeve member that is connected to the intermediate shaft and fits onto an outer periphery of the valve body,
the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
The intermediate chamber communicates with a valve port of the valve body through a gap between the sleeve member and the valve body.
The motor-operated valve of the present invention comprises:
A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of contacting the stopper portion after the valve body is seated on the valve seat,
The valve seat is coaxially formed within an annular recess of the valve body, and the stopper portion is formed on a periphery of the annular recess.

The present invention provides an electrically operated valve that is less likely to become clogged between the valve body and the valve seat.

FIG. 1 is a vertical sectional view of a motor-operated valve according to a first embodiment. FIG. 2 is an enlarged vertical cross-sectional view showing a lower part of the valve body unit. FIG. 3 is an enlarged vertical cross-sectional view showing a lower part of the valve body unit. FIG. 4 is an enlarged vertical cross-sectional view showing a lower part of a valve body unit according to a modified example. FIG. 5 is a vertical sectional view of a motor-operated valve according to the second embodiment.

Below, an embodiment of the motor-operated valve according to the present invention will be described with reference to the drawings. In this specification, the rotor side will be described as the upper side, and the valve body side will be described as the lower side.

First Embodiment
1 is a vertical cross-sectional view of a motor-operated valve 1 according to a first embodiment. The motor-operated valve 1 of the present embodiment is used, for example, to adjust the flow rate of a refrigerant in a refrigeration cycle. The axis of the motor-operated valve 1 is designated by L.

The motor-operated valve 1 of this embodiment is composed of a valve body 10 having a valve seat 15 formed inside the valve chamber VC, a can 3 of a cylindrical shape with a top fixed to the valve body 10 via a base plate 11, a stepping motor 5 consisting of a stator 55 fitted onto the can 3 and a rotor 57 mounted inside the can 3, a cover 9 covering the periphery of the stator 55, a gear-type reduction mechanism 6 that reduces the speed and transmits the rotational torque of the rotor 57, a valve body 4 that moves toward and away from the valve seat 15 to control the amount of fluid passing through, and a screw drive member (output shaft) 22 that converts the rotational movement of the output gear of the reduction mechanism 6 into linear movement via a screw feed mechanism 27 to drive the valve body 4. The can is a member having a cylindrical portion attached to the valve body side of the motor-operated valve so that the inside is sealed (the can 3 has a cylindrical portion with a bottom).

The stepping motor 5 has a stator 55 consisting of a yoke 51, a bobbin 52, a coil 53, etc., and a rotor 57 that is arranged inside the can 3 and can rotate freely with respect to the can 3, with a rotor support member 56 fixed to its upper inside. The stator 55 is fitted and fixed to the outside of the can 3, and is covered by a resin cover 9.

A valve port 16 that communicates with the internal valve chamber VC is formed at the bottom end of the cylindrical valve body 10, and a first pipe T1 is connected to the valve port 16 side by brazing or the like, and a second pipe T2 is also connected by brazing or the like so as to communicate with an opening 12 formed on the side of the valve chamber VC. The axis of the second pipe T2 is O. The axis O is perpendicular to the axis L. Here, the pressure in the second pipe T2 is higher than the pressure in the first pipe T1.

A threaded bearing member 13 having a female thread portion 13a formed at the central lower end side is inserted into the upper part of the valve chamber VC of the valve body 10 and is fixed to the valve body 10 by press fitting or the like.

The reduction mechanism 6 has a sun gear 61 formed integrally with the rotor support member 56 on the inner periphery side of the rotor 57, a fixed ring gear 62 fixed via a thin-walled cylindrical body 66 fixed to the upper part of the valve body 10, a planetary gear 63 arranged between the sun gear 61 and the fixed ring gear 62 and meshing with them, a carrier 64 that rotatably supports the planetary gear 63, and a cylindrical output gear member 65 with a bottom that has teeth on its inner periphery that mesh with the planetary gear 63, and these constitute a paradox planetary gear reduction mechanism. The number of teeth of the fixed ring gear 62 is set to be different from the number of teeth of the output gear member 65.

The shaft member 8 passes through the rotor support member 56 and the sun gear 61 and holds them rotatably, and the upper end of the shaft member 8 is supported by a support member 81 located inside the top of the can 3.

The upper part of the stepped cylindrical output shaft part 29 formed on the upper part of the screw drive member 22 is press-fitted into the center of the bottom of the output gear member 65, and the lower end of the shaft member 8 is press-fitted into the upper opening of this output shaft part 29.

The female threaded portion 13a of the screw bearing member 13 is screwed into the male threaded portion 22a formed on the lower part of the screw drive member 22. The rotational movement of the output gear member 65 (i.e., the rotor 57) is converted into linear movement along the axis L by the screw feed mechanism (conversion mechanism) 27 consisting of the male threaded portion 22a and the female threaded portion 13a.

The output shaft portion 29 is connected to the screw drive member 22 so that it can rotate together with it. When the output gear member 65 (rotor 57) rotates, the output shaft portion 29 and the screw drive member 22 rotate together and move linearly relative to the valve body 10 along the axis L.

The linear movement of the screw drive member 22 is transmitted to the valve body unit 30 via a ball joint 25 consisting of a ball 23 and a ball seat 24.

2 and 3 are enlarged longitudinal sectional views of the lower part of the valve body unit 30. FIG. 2 shows the state immediately after the valve body 4 is seated on the valve seat 15 by the descent of the intermediate shaft 31 described later, and FIG. 3 shows the state in which the intermediate shaft 31 is further lowered and the sleeve member 33 abuts against the stopper portion 10b. With reference to FIGS. 1 to 3, the valve body unit 30 is composed of the intermediate shaft 31 connected to the ball joint 25, an elastically deformable elastic tubular body (elastic body) 32 formed of resin, rubber (NBR), or the like, a sleeve member (locking member) 33, and the valve body 4. The elastic tubular body 32 is made of, for example, NBR, H-NBR, EPDM, silicone rubber, fluororubber, urethane rubber, or the like, and its Young's modulus is preferably in the range of 0.1 to 10 MPa. In this embodiment, the elastic tubular body 32 is a solid cylindrical shape (i.e., a columnar shape).

The cylindrical intermediate shaft 31 is composed of an intermediate base 31a and an intermediate flange 31b connected to the upper end of the intermediate base 31a. An intermediate recess 31c is formed from the center of the intermediate flange 31b to the intermediate base 31a, into which the lower end of the ball seat 24 is press-fitted. A reduced diameter portion 31d is formed on the outer periphery of the lower end of the intermediate base 31a.

Referring to Figures 2 and 3, the cylindrical sleeve member 33 is made up of a thin-walled portion 33a, which is pressed into the step of the reduced diameter portion 31d of the intermediate shaft 31, and a thick-walled portion 33b, which are coaxially connected. The thin-walled portion 33a and the thick-walled portion 33b have the same outer diameter and are larger than the outer diameter of the annular recess 10a. A sleeve cone portion 33c is formed on the outer periphery of the lower end of the thick-walled portion 33b, and a communication hole 33d is formed near the lower end of the thick-walled portion 33b, penetrating it in the radial direction.

The valve body 4 is composed of a valve body base 4a that is slidably fitted to the inner circumference of the thick-walled portion 33b, and a valve body flange portion 4b that is connected to the upper end of the valve body base 4a. A valve body recess 4d is formed in the center of the valve body flange portion 4b. The valve body cone portion 4c formed at the lower end of the valve body base 4a is positioned to protrude into the valve port 16.

The elastic cylindrical body 32 is placed in the valve body recess 4d, with its upper surface abutting against the lower end flat surface of the intermediate shaft 31; that is, the elastic cylindrical body 32 is sandwiched between the intermediate shaft 31 and the valve body 4 in the vertical direction. The communication hole 33d of the sleeve member 33 communicates at its inner end side with the intermediate chamber MC defined between the lower end flat surface of the intermediate base 31a and the valve body flange 4b of the valve body 4, via the gap between the outer periphery of the valve body 4 and the inner periphery of the sleeve member 33. Therefore, when the motor-operated valve 1 is closed, the pressure in the valve chamber VC is approximately equal to the pressure in the intermediate chamber MC. The elastic cylindrical body 32 is disposed in the intermediate chamber MC.

The valve body 10 has an annular recess 10a formed coaxially with the axis L on the bottom surface of the valve chamber VC. A valve port 16 is formed in the center of the annular recess 10a. A valve seat 15 is formed at the upper end of the valve port 16. The upper end (periphery) of the annular recess 10a constitutes an annular stopper portion 10b. The inner diameter of the valve seat 15 is A, and the inner diameter of the stopper portion 10b is B. As shown in FIG. 2, the distance in the axial direction L between the stopper portion 10b and the sleeve cone portion 33c immediately after the valve body 4 is seated on the valve seat 15 by the descent of the intermediate shaft 31 is C. As shown in FIG. 3, the distance in the axial direction L between the lower surface of the valve body flange portion 4b and the step portion between the thin portion 33a and the thick portion 33b of the sleeve member 33 when the sleeve member 33 is in contact with the stopper portion 10b is D, so C=D.

In FIG. 1, the cylindrical spring case 19 arranged around the valve body unit 30 is made up of a case enlarged diameter portion 19a, a case reduced diameter portion 19b, and an upper end flange portion 19c extending radially outward from the upper end of the case enlarged diameter portion 19a. The upper end flange portion 19c engages with an inner peripheral step portion of the valve body 10 and is fixed and held by the threaded bearing member 13. The case reduced diameter portion 19b slidably holds the outer periphery of the sleeve member 33.

The compression coil spring 26 is arranged in a compressed state with its lower end abutting against the step between the case enlarged diameter portion 19a and the case reduced diameter portion 19b, and its upper end engaging with the intermediate flange portion 31b of the intermediate shaft 31, thereby biasing the valve body 4 in the constantly open valve direction.

(Operation of motor-operated valve)
When a control device (not shown) supplies a valve-closing control signal with a predetermined number of pulses to the stator 55 to rotate the rotor 57 of the stepping motor 5 in one direction, the rotational speed is input from the sun gear 61 to the reduction mechanism 6, and the rotational speed reduced by the reduction mechanism 6 is transmitted to the screw drive member 22 via the output shaft 29. When the screw drive member 22 rotates in one direction, the female threaded portion 13a and the male threaded portion 22a screw relative to each other, and the screw drive member 22 moves downward in the direction of the axis L according to the rotational speed. The thrust of the screw drive member 22 urges the intermediate shaft 31 downward via the ball joint 25, and the intermediate shaft 31 descends against the urging force of the compression coil spring 26.

As the intermediate shaft 31 descends, the sleeve member 33 descends simultaneously while being guided by the spring case 19, and the valve body 4 is urged downward via the elastic cylindrical body 32 pressed by the lower end of the intermediate shaft 31. When the valve body 4 descends while being guided by the sleeve member 33, the valve body cone portion 4c seats on the valve seat 15 and the valve port 16 is closed (see Figure 2). This interrupts the flow of fluid between the pipes T2 and T1 across the valve chamber VC.

The valve-closing control signal input to the stepping motor 5 from a control device (not shown) takes into account backlash in the drive path and the like, and includes a number of pulses for the rotor 57 to rotate a certain angle further after the valve body cone portion 4c seats on the valve seat 15. Therefore, even after the valve body cone portion 4c seats on the valve seat 15, the intermediate shaft 31 receives a driving force in the downward direction.

If the intermediate shaft 31 and the valve body 4 were integral, the valve body cone portion 4c would be urged toward the valve seat 15 in response to the generated driving force, creating a high surface pressure between them. In particular, if the motor-operated valve 1 has a gear-type reduction mechanism 6, the surface pressure between the valve body cone portion 4c and the valve seat 15 would be excessive. In such a situation, if a hard foreign object is present between the valve body cone portion 4c and the valve seat 15, indentations or scratches will be created on at least one of the valve body cone portion 4c and the valve seat 15, which may cause fluid leakage when the valve is closed.

According to this embodiment, even after the valve body cone portion 4c is seated on the valve seat 15, the intermediate shaft 31 receives a driving force in a downward direction, but since the valve body 4 is stationary, the elastic cylindrical body 32 is compressed in the direction of the axis L. Therefore, the elastic cylindrical body 32 exerts a predetermined elastic force by being compressed, and the elastic force urges the valve body 4 downward, but this elastic force is considerably smaller than the driving force received by the intermediate shaft 31. Therefore, the surface pressure between the valve body cone portion 4c and the valve seat 15 is relatively small, and even if a hard foreign object is interposed between the valve body cone portion 4c and the valve seat 15, the occurrence of indentations or scratches is suppressed, and therefore fluid leakage when the valve is closed can be suppressed. In addition, by using the elastic cylindrical body 32, the valve body 4 is not rigidly connected to the intermediate shaft 31, so there is an advantage that the movement of the valve body 4 is less likely to be restricted.

When the rotor 57 of the stepping motor 5 rotates further in one direction after the valve body cone portion 4c is seated on the valve seat 15, the sleeve member 33 descends together with the intermediate shaft 31, and the sleeve cone portion 33c abuts against the stopper portion 10b (see FIG. 3). This abutment locks the sleeve member 33 and the intermediate shaft 31, preventing damage to the valve body unit 30 due to over-rotation of the rotor 57.

The angle by which the rotor 57 rotates after the valve body cone portion 4c seats on the valve seat 15 and before the sleeve cone portion 33c abuts against the stopper portion 10b is an angle equivalent to the distance C in the direction of the axis L. Therefore, a control device (not shown) stores the number of pulses corresponding to this angle as a design value in advance and supplies a control signal including this to the motor-operated valve 1.

However, if distance C differs significantly from the design value due to manufacturing errors, etc., there is a risk that the sleeve cone portion 33c will come into excessive contact with the stopper portion 10b. To prevent this, distance C must be precisely controlled, and to do so, it is necessary to precisely machine the inner diameter A of the valve seat 15, the inner diameter B of the stopper portion 10b, and the distance E in the axial direction L between the valve seat 15 and the stopper portion 10b shown in Figure 2.

According to this embodiment, when processing the material of the valve body 10, a rotary cutting tool (not shown) is inserted from above to machine the annular recess 10a, and the valve orifice 16 can be machined coaxially within the machined annular recess 10a. Therefore, the inner diameter of the valve seat 15 and the inner diameter of the stopper portion 10b can be machined with high precision, and the inner diameter A, inner diameter B, and distance E can be obtained with high precision.

On the other hand, when a valve opening control signal is supplied from a control device (not shown) to the stator 55 to rotate the rotor 57 of the stepping motor 5 in the other direction, the screw drive member 22 moves upward in the direction of the axis L via the reduction mechanism 6 and the screw feed mechanism 27. As a result, the intermediate shaft 31 rises in accordance with the biasing force of the compression coil spring 26.

When the sleeve member 33 rises together with the intermediate shaft 31, as shown in FIG. 3, the lower surface of the valve body flange 4b comes into contact with the inner peripheral step between the thin-walled portion 33a and the thick-walled portion 33b of the sleeve member 33 and is urged upward, causing the valve body 4 to rise. When the valve body 4 rises, the valve body cone portion 4c separates from the valve seat 15 and the valve port 16 opens. This allows fluid to flow from the second pipe T2 through the valve chamber VC to the first pipe T1.

In the above-described embodiment, the sleeve member 33 has a communication hole 33d, which allows communication through the gap between the outer periphery of the valve body 4 and the inner periphery of the sleeve member 33, making the pressures in the intermediate chamber MC and the valve chamber VC approximately equal.

For this reason, if the motor-operated valve 1 is used in an application in which the pressure in the first pipe T1 is higher than the pressure in the second pipe T2, when the valve is closed, the pressure in the valve port 16 and the annular recess 10a will be higher than the pressure in the intermediate chamber MC, and the valve body 4 will be urged upward by the pressure difference across the valve body 4, causing the valve body cone portion 4c to move away from the valve seat 15, which may result in fluid leakage. In response to this, the following modified example can eliminate or mitigate such a problem.

(Modification)
Fig. 4 is an enlarged longitudinal cross-sectional view similar to Fig. 2 showing the lower part of the valve body unit 30A according to the modified example. Unlike the embodiment described above, in the valve body unit 30A of this modified example, the sleeve member 33A does not have a communication hole. The other configurations are the same as those of the embodiment described above, so duplicated explanations will be omitted.

According to this modified example, since the sleeve member 33A does not have a communication hole, the intermediate chamber MC communicates with the annular recess 10a (and the valve port 16) through the gap between the outer periphery of the valve body 4 and the inner periphery of the sleeve member 33A. Therefore, even if the pressure in the first pipe T1 is higher than the pressure in the second pipe T2, when the valve is closed, the pressure in the valve port 16 and the annular recess 10a becomes approximately equal to the pressure in the intermediate chamber MC, no pressure difference occurs across the valve body 4, and the valve body cone portion 4c is prevented from moving away from the valve seat 15. Therefore, continuous leakage of fluid from the gap between the valve body cone portion 4c and the valve seat 15 is prevented when the valve is closed.

Second Embodiment
5 is a vertical cross-sectional view of an electric valve 1B according to a second embodiment. The electric valve 1 of this modification is different from the first embodiment in the configuration of the valve body unit 30B. The valve body unit 30B is composed of an intermediate shaft 31 connected to the ball joint 25, an elastically deformable elastic cylindrical body 32 made of resin, rubber (NBR), or the like, a sleeve member 33B, and a valve body 4B. The configuration other than the sleeve member 33B and the valve body 4B is the same as in the above-mentioned embodiment, so repeated explanations will be omitted.

The cylindrical sleeve member 33B is made up of a thin-walled portion 33Ba, which is pressed into the stepped portion of the reduced diameter portion 31d of the intermediate shaft 31, a thick-walled portion 33Bb, and a large cylindrical portion 33Bd, which are arranged coaxially. The thin-walled portion 33Ba and the thick-walled portion 33Bb have the same outer diameter, but the large cylindrical portion 33Bd has a larger outer diameter. A sleeve cone portion 33Bc that can come into contact with the stopper portion 10b is formed on the outer periphery of the lower end of the large cylindrical portion 33Bd.

The valve body 4B is composed of an upper valve body 41B and a lower valve body 42B, which are separate members. The upper valve body 41B is composed of a valve body base 4Ba that is slidably fitted to the inner circumference of the thick portion 33Bb of the sleeve member 33B, and a valve body flange portion 4Bb that is connected to the upper end of the valve body base 4Ba. A valve body recess 4Bd is formed in the center of the valve body flange portion 4Bb. A blind hole-shaped circular opening 4Be is formed in the lower end of the valve body base 4Ba.

The lower valve body 42B consists of a valve shaft 4Bf that is press-fitted into the circular opening 4Be, and a disk portion 4Bg that is connected to the lower end of the valve shaft 4Bf. The outer diameter of the disk portion 4Bg is larger than the outer diameter of the valve body base portion 4Ba. A valve body cone portion 4Bc is formed on the outer periphery of the lower end of the disk portion 4Bg, and can be seated on the valve seat 15.

In this embodiment, the inner diameter of the valve port 16 can be enlarged compared to the first embodiment, providing an electrically operated valve 1 that can pass a larger amount of fluid.

Reference Signs List 1, 1B Motor-operated valve 10 Valve body 3 Can 4, 4B Valve body 5 Stepping motor 53 Coil 55 Stator 57 Rotor 6 Speed reducing mechanism 8 Shaft member 9 Cover 30, 30A, 30B Valve body unit 31 Intermediate shaft 32 Elastic cylindrical body MC Intermediate chamber VC Valve chamber T1 First pipe T2 Second pipe L Axis

Claims (7)

A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction ,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of contacting the stopper portion after the valve body is seated on the valve seat,
the locking member is a sleeve member that is connected to the intermediate shaft and fits onto an outer periphery of the valve body,
the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
the sleeve member has a communication hole that communicates the intermediate chamber with a valve chamber in the valve body through a gap between the sleeve member and the valve body;
A motor-operated valve. A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of contacting the stopper portion after the valve body is seated on the valve seat,
the locking member is a sleeve member that is connected to the intermediate shaft and fits onto an outer periphery of the valve body,
the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
The intermediate chamber communicates with a valve port of the valve body via a gap between the sleeve member and the valve body.
A motor-operated valve. A valve body having a valve seat;
an output shaft that moves in an axial direction by the driving force of a motor;
A valve body unit,
the valve body unit includes an intermediate shaft connected to the output shaft and movable in an axial direction, a valve body that moves in the axial direction to approach or move away from the valve seat, and an elastic body that is elastically deformable and disposed between the intermediate shaft and the valve body along the axial direction,
The valve body has an annular stopper portion,
The valve body unit has a locking member that moves together with the intermediate shaft,
the engaging member is capable of abutting against the stopper portion after the valve body is seated on the valve seat,
The valve seat is coaxially formed within an annular recess of the valve body, and the stopper portion is formed on a periphery of the annular recess.
A motor-operated valve. The locking member is a sleeve member that is connected to the intermediate shaft and fits onto an outer periphery of the valve body.
4. The motor-operated valve according to claim 3 . the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
the sleeve member has a communication hole that communicates the intermediate chamber with a valve chamber in the valve body through a gap between the sleeve member and the valve body.
5. The motor-operated valve according to claim 4 . the elastic body is disposed in an intermediate chamber formed between the intermediate shaft and the valve body,
The intermediate chamber communicates with a valve port of the valve body via a gap between the sleeve member and the valve body.
5. The motor-operated valve according to claim 4 . The driving force of the motor is transmitted to the output shaft via a gear-type reduction mechanism.
The motor-operated valve according to any one of claims 1 to 6 .

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