JP2021148182A - Motor-operated valve and refrigeration cycle system - Google Patents

Abstract

To provide a motor-operated valve and a refrigeration cycle system capable of suppressing valve leakage while improving efficiency.SOLUTION: A motor-operated valve 10 includes: a valve body 1 constituting a valve chest 1C and a valve seat portion 13; a valve element 2 changing an opening of a valve port 14 by being kept into contact with and separated from the valve seat portion 13 in an axial direction L; a stepping motor 3 as a driving portion for driving a rotor shaft 32 as a rotating shaft forward and backward; a valve holder 6 disposed over the valve element 2 and the rotor shaft 32; and a valve spring 9 for energizing the valve element 2 in a valve closing direction. The motor-operated valve 10 includes a rolling bearing 8 between the valve element 2 as a shaft portion and the valve holder 6, a radial clearance C1 is formed between the rolling bearing 8 and the valve element 2, and the valve element 2 and the valve holder 6 are connected in a manner of being relatively displaceable in a radial direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electric valve and a refrigeration cycle system used in a refrigeration cycle system or the like.

Conventionally, an electric valve that opens and closes a valve by rotationally driving a rotary shaft such as a rotor shaft by a rotary drive unit such as a stepping motor and converting the rotary motion of the rotary shaft into a linear motion by a screw feed mechanism has been used. For example, see Patent Documents 1, 2, etc.). In this type of electric valve, the valve body and the screw feed mechanism are used to suppress the rotation of the valve body and excessive pressing of the valve body against the valve seat to improve the durability due to the seating of the valve. A valve holder containing a bearing and a valve spring is provided between the two. There are two types of bearings built into such valve holders: rolling bearings and sliding bearings. Rolling bearings have a smaller rotational load and require less output from the rotational drive unit. It becomes an electric valve.

Japanese Patent No. 6472637 China Utility Model Registration No. 208519284

However, in the conventional electric valve as disclosed in Patent Documents 1 and 2, it is necessary to seat the valve body and the valve seat in a state of being coaxially positioned in order to reduce valve leakage. As shown in FIG. 11, the valve body 95 and the valve seat 96 (valve port 97) are misaligned due to variations in dimensional errors due to component dimensional tolerances during component manufacturing, assembly tolerances during assembly, and the like. There was a problem that it was difficult to eliminate the possibility of valve leakage. That is, in the structure of Patent Document 1, as shown in FIG. 11, the tip of the valve shaft 91 and the spring receiver 92 are in contact with each other under the load of the valve spring 93, and the lower end of the valve spring 93 is further positioned. Since it is in direct contact with the valve body 95 fixed to the valve guide 94, the deviation between the axis L'of the valve body 95 and the axis L of the valve port 97 of the valve seat portion 96 when the valve body 95 is seated It is difficult to correct and valve leakage is likely to occur. Further, in the structure of Patent Document 2, the rolling bearing is accommodated in a slight radial gap between the screw shaft and the accommodating groove of the valve body, and there is almost no degree of freedom in the radial direction. Cannot be corrected to match the axis of the valve seat, so valve leakage is likely to occur.

An object of the present invention is to provide an electric valve and a refrigeration cycle system capable of suppressing valve leakage while improving efficiency.

The electric valve of the present invention includes a valve body that constitutes a valve chamber and a valve seat portion, a valve body that changes the opening degree of the valve port by being brought into contact with the valve seat portion in the axial direction, and a drive that drives the rotation shaft forward and backward. An electric valve including a portion, a valve holder extending over the valve body and the rotating shaft, and a valve spring for urging the valve body in the valve closing direction, and at least one of the valve body and the rotating shaft. Has a shaft portion rotatably inserted into the valve holder, includes a rolling bearing between the shaft portion and the valve holder, and the rolling bearing and at least one of the shaft portion and the valve holder. A radial gap is provided between the, and the shaft portion and the valve holder are connected so as to be relatively displaceable in the radial direction.

According to the present invention, since a rolling bearing is used as a bearing for connecting the valve body or the shaft portion of the rotating shaft and the valve holder so as to be relatively rotatable, high efficiency can be achieved. Further, a radial gap is provided between the rolling bearing and at least one of the shaft portion and the valve holder, and the shaft portion and the valve holder are connected so as to be relatively displaceable in the radial direction. Therefore, when the valve body is seated on the valve seat portion, the shaft portion and the valve holder are displaced relative to each other in the radial direction only within the range of the gap, and the valve body can be seated coaxially with the valve seat portion. Valve leakage can be reduced.

At this time, a gap in the axial direction is provided between the rolling bearing and at least one of the shaft portion and the valve holder, and the shaft portion and the valve holder are relative to each other in the axial direction. It is preferably connected in a displaceable manner.

In the above configuration, when the valve is closed, the valve body contracts to give an appropriate pressing load to the valve body, so that the rotating shaft tries to lower the valve body further than the seating position, but the valve body is the valve seat. When seated on the portion, the shaft portion and the valve holder are displaced relative to each other in the axial direction, so that the shaft portion and the valve holder are freed by the gap in the axial direction, so that no force is applied to the valve body. As a result, even if the axis of the rotating shaft and the axis of the valve seat (valve port) are misaligned, the shaft and the valve holder can be displaced relative to each other in the radial and axial directions without a large sliding resistance. Therefore, the valve body can be seated coaxially with the valve seat portion, and valve leakage can be reduced.

Further, the shaft portion is preferably a rod shaft of the valve body. Further, the shaft portion is preferably the tip end portion of the rotating shaft.

The refrigeration cycle system of the present invention is a refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, and any of the above electric valves is used as the expansion valve. It is characterized by.

According to the present invention as described above, since the electric valve of the present invention can suppress valve leakage while improving efficiency, it saves energy during operation and causes a problem. It can be a difficult refrigeration cycle system.

According to the electric valve and the refrigeration cycle system of the present invention, valve leakage can be suppressed while improving efficiency.

It is a vertical sectional view which shows the electric valve which concerns on 1st Embodiment of this invention. It is a vertical cross-sectional view which shows the main part at the time of opening the valve of the electric valve. It is a vertical cross-sectional view which shows the main part at the time of contact with the valve body of the electric valve, and a valve seat. It is a vertical cross-sectional view which shows the main part at the time of seating of the electric valve. It is a vertical sectional view which shows the main part of the electric valve which concerns on 2nd Embodiment of this invention. It is a vertical cross-sectional view which shows the main part at the time of valve opening of the electric valve which concerns on 3rd Embodiment of this invention. It is a vertical cross-sectional view which shows the main part at the time of contact with the valve body and the valve seat of the electric valve of the 3rd Embodiment. It is a vertical cross-sectional view which shows the main part at the time of seating of the electric valve of the 3rd Embodiment. It is a vertical sectional view which shows the main part of the electric valve which concerns on 4th Embodiment of this invention. It is a figure which shows an example of the refrigeration cycle system of this invention. It is a vertical cross-sectional view which shows the main part of the conventional electric valve.

The electric valve according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 4. As shown in FIG. 1, the electric valve 10 of the present embodiment includes a valve body 1, a valve body 2, a valve holder 6, and a stepping motor 3 as a drive unit. The concept of "upper and lower" in the following description corresponds to the upper and lower parts in the drawing of FIG.

The valve body 1 has a cylindrical valve housing member 1A and a support member 5 fixed to the upper end opening of the valve housing member 1A.

A substantially cylindrical valve chamber 1C is formed inside the valve housing member 1A, and a first joint pipe 11 communicating with the valve chamber 1C from the side surface side is attached. Further, a substantially cylindrical valve seat member 15 is inserted into the valve housing member 1A from the bottom surface side, and the valve seat portion 13 is configured by the valve seat member 15 fixed by brazing. A valve port 14, which is a valve opening, is formed in the valve seat portion 13. Further, on the bottom surface side of the valve housing member 1A, a second joint pipe 12 is fixed to the bottom portion of the valve housing member 1A by brazing so as to be gently continuous with the lower end portion of the inner surface of the valve seat member 15. ing. When the refrigerant as a fluid flows in from the first joint pipe 11, the refrigerant that has passed through the valve port 14 via the valve chamber 1C flows out from the second joint pipe 12. Further, when the refrigerant flows in from the second joint pipe 12, the refrigerant that has passed through the valve chamber 1C through the valve port 14 flows out from the first joint pipe 11.

The support member 5 is welded and fixed to the upper end opening of the valve housing member 1A via a fixing bracket 41. A female threaded portion 5a formed coaxially with the axis L of the valve port 14 or the like is provided at the center of the upper side of the support member 5, and a cylindrical guide hole having a diameter larger than the outer circumference of the female threaded portion 5a is provided below. 5c is formed.

The valve body 2 has a rod shaft 22 as a shaft portion provided with a needle portion 21 at the lower tip. The rod shaft 22 is composed of an upper diameter reducing portion 22a and a lower diameter expanding portion 22b, and a flange portion 23 is formed at the upper end portion thereof. A rolling bearing 8 (described later) is arranged on the outer peripheral surface side of the rod shaft 22, and the rolling bearing 8 is prevented from coming off by a flange portion 23 having an enlarged upper end portion of the rod shaft 22.

The stepping motor 3 includes a can 4, a magnet rotor 31 provided in the can 4, a rotor shaft 32, a stator coil (not shown), and a rotation stopper mechanism 7 of the stepping motor 3.

The can 4 is airtightly fixed to the upper end of the valve housing 1A by welding or the like, and houses a support member 5, a magnet rotor 31, which will be described later, and a rotation stopper mechanism 7. The outer peripheral portion of the magnet rotor 31 is magnetized in multiple poles, and the rotor shaft 32 is fixed at the center thereof. The lower end of the rotor shaft 32 is connected to the rod shaft 22 of the valve body 2 via the valve holder 6 and the rolling bearing 8. Further, the rotor shaft 32 has a male screw portion 32a formed on the upper surface of the intermediate portion thereof. The male screw portion 32a is screwed into the female screw portion 5a of the support member 5, and the male screw portion 32a and the female screw portion 5a constitute a screw feed mechanism 16 of the drive portion. The screw feed mechanism 16 converts the rotary motion of the stepping motor 3 into a linear motion of the rotor shaft 32, whereby the valve body 2 is driven forward and backward in the axis L direction. The stator coil is arranged on the outer circumference of the can 4, and when a pulse signal is given to the stator coil, the magnet rotor 31 is rotated according to the number of pulses, and the rotor shaft 32 is rotated. There is.

In the rotation stopper mechanism 7 of the stepping motor 3, the guide support 7A is fixed to the ceiling of the can 4, and the guide support 7A has a cylindrical shape that hangs down from the center of the ceiling of the can 4 along the axis. It includes a guide 76, a spiral guide 77 fixed to the outer periphery of the guide 76, and a movable slider 78 that is guided by the spiral guide 77 and can rotate and move up and down. The movable slider 78 is provided with a claw portion 78a protruding outward in the radial direction, and the magnet rotor 31 is provided with an extension portion 31a extending upward and in contact with the claw portion 78a. When the portion 31a pushes the claw portion 78a, the movable slider 78 rotates and moves up and down following the spiral guide 77. Further, a cylindrical member 7B that guides the upper part of the rotor shaft 32 is fitted inside the cylindrical guide 76.

The spiral guide 77 is formed with an upper end stopper 77a that defines the uppermost end position of the magnet rotor 31 and a lower end stopper 77b that defines the lowermost end position of the magnet rotor 31. When the movable slider 78 lowered with the forward rotation of the magnet rotor 31 comes into contact with the lower end stopper 77b, the movable slider 78 cannot rotate at this contacted position, which restricts the rotation of the magnet rotor 31 and the valve body. The descent of 2 is also stopped. On the other hand, when the movable slider 78 that has risen due to the reverse rotation of the magnet rotor 31 comes into contact with the upper end stopper 77a, the movable slider 78 cannot rotate at this contacted position, which restricts the rotation of the magnet rotor 31. The rise of the valve body 2 is also stopped.

As shown in FIG. 2, the valve holder 6 has an insertion hole 61a through which the lower tip portion of the rotor shaft 32 is inserted in the center of the upper surface portion of the cylindrical holder body 61, and the lower tip portion of the rotor shaft 32. Is rotatably engaged with. Further, a flange portion 32b is provided at the lower tip portion of the rotor shaft 32 so as not to come off from the inside of the holder main body 61. The upper end of the valve spring 9 is in contact with the lower surface of the flange portion 32b of the rotor shaft 32. The rolling bearing 8 is connected to a ring-shaped first member 81 arranged on the outer peripheral surface side of the reduced diameter portion 22a of the rod shaft 22 of the valve body 2 via steel balls 8a as a plurality of rolling members. It is composed of a ring-shaped second member 82 and a bearing having the ring-shaped second member 82. In the rolling bearing 8, the second member 82 is urged by a valve spring 9, and the lower end of the second member 82 comes into contact with the lower end (press-fit member 63) of the holder body 61. The valve holder 6 has an insertion hole 61b in the center of the lower surface of the holder body 61, and the enlarged diameter portion 22b of the rod shaft 22 of the valve body 2 is inserted into the insertion hole 61b. Further, as shown in FIG. 1, a ring-shaped press-fitting member 63 is press-fitted into the insertion hole 61b, and the press-fitting member 63 prevents the valve body 2 and the rolling bearing 8 from coming off from the valve holder 6. Here, the lower end of the holder body 61 is press-fitted with the press-fitting member 63, but instead, a ring-shaped member (retaining ring or the like) is welded or crimped to the lower end of the holder body 61. It may be fixed, and is not limited to these as long as it has a structure capable of preventing the rolling bearing 8 from coming off.

Further, a radial gap C1 of the rod shaft 22 is provided between the first member 81 inside the rolling bearing 8 and the reduced diameter portion 22a of the rod shaft 22 in the valve body 2. Further, a gap C2 in the axial direction L is provided between the lower side surface of the rolling bearing 8 and the enlarged diameter portion 22b of the rod shaft 22 in the valve body 2.

As shown in FIG. 2, when the valve is opened, the position of the axis L'of the valve body 2 is shifted to the left side from the position of the axis L of the valve seat portion 13, for example. In order to bring the seated state, the valve body 2 is lowered by the drive of the stepping motor 3, and as shown in FIG. 3, when the needle portion 21 comes into contact with the valve seat portion 13, the axis L'of the valve body 2 is still present. Is offset to the left side of the position of the axis L of the valve seat portion 13 (valve port 14), and the left side of the needle portion 21 is in contact with the left side of the valve seat portion 13. At this time, a force as shown by an arrow (a force in the right direction in the radial direction and an upward force in the axis L direction) acts on the contact portion of the valve body 2 with the valve seat 13. When the rotor shaft 32 is further lowered, the valve body 2 is displaced upward so as to shrink the gap C2 in the axis L direction relative to the valve holder 6, and the radial gap C1 is corrected so as to correct the radial deviation. When seated with the rotary stopper mechanism 7 working, the valve body 2 moves to the upper right relative to the valve holder 6 as compared with when the valve is opened. Then, since the valve body 2 and the valve port 14 are positioned coaxially, the needle portion 21 is seated on the entire circumference of the upper end opening (valve seat portion 13) of the valve port 14.

According to the above embodiment, since the rolling bearing 8 is used as the bearing that connects the rod shaft 22 of the valve body 2 and the valve holder 6 so as to be relatively rotatable, it is possible to suppress the rotation of the valve body 2 when the valve is closed. Since the rotational load due to the sliding resistance between the valve body 2 and the valve seat 13 is reduced, highly efficient operation can be achieved. Further, a radial gap C1 is provided between the rolling bearing 8 and the rod shaft 22 of the valve body 2, and the rod shaft 22 and the valve holder 6 are connected so as to be relatively displaceable in the radial direction. Therefore, when the valve body 2 is seated on the valve seat portion 13, the rod shaft 22 and the holder body 61 of the valve holder 6 are displaced relative to each other in the radial direction only within the range of the gap C1 with respect to the valve seat portion 13. The valve body 2 can be seated coaxially, and valve leakage can be reduced.

Further, since a gap C2 is provided between the rolling bearing 8 and the rod shaft 22 of the valve body 2 in the axis L direction, the rotor shaft 32 further lowers after the valve body 2 comes into contact with the valve seat. When the valve body 2 is seated on the seating portion 13, the rod shaft 22 and the valve holder 6 are displaced relative to each other in the axis L direction, so that the lower surface of the flange portion 23 of the rod shaft 22 and the rolling bearing 8 are the first. Since the upper surface of the member 81 is separated and the valve body 2 is freed by the gap in the axis L direction, even if the axis L'of the rotor shaft 32 and the axis L of the valve port 14 are deviated from each other, the rod shaft 22 and the rod shaft 22 When the valve holder 6 is displaced relative to the radial direction and the axis L direction, the valve body 2 can be seated coaxially with the valve seat portion 13, and valve leakage can be reduced. When the axis L'is inclined to the right side opposite to the drawing with respect to the axis L, the valve body 2 has a gap C1 and C2 on the upper left when the valve body 2 is seated on the seating portion 13. Displace to the position of.

Next, the electric valve according to the second embodiment of the present invention will be described with reference to FIG. The electric valve of the present embodiment includes a valve main body 1, a valve body 2, a valve holder 6, and a stepping motor 3 as a driving unit, similarly to the electric valve 10 of the first embodiment. In the electric valve of the present embodiment, a part of the valve holder 6 is different from the electric valve 10 of the first embodiment. The differences will be described in detail below.

In the electric valve of the present embodiment, there is no flange 32b at the lower end of the rotor shaft 32, there is no insertion hole 61a above the holder body 61 of the valve holder 6, and there is no lower end of the rotor shaft 32 and the upper surface of the holder body 61. The electric valve 10 of the first embodiment is different from the electric valve 10 of the first embodiment in that the central portion of the valve spring 9 is integrally connected to the ceiling surface inside the cylinder of the holder body 61 and the upper end of the valve spring 9 is in contact with the ceiling surface. The rotor shaft 32 and the holder body 61 are not limited to those integrally connected, but may be formed separately and attached by an appropriate attachment means.

In the electric valve of the present embodiment as described above, the same effect as that of the first embodiment can be obtained with respect to the correction for the deviation between the axis of the valve body 2 and the axis of the valve seat portion 13. In addition to this, in the valve holder 6, since the lower end portion of the rotor shaft 32 and the holder body 61 of the valve holder 6 are integrally formed, the configuration is simplified as compared with the electric valve 10 of the first embodiment. Can be planned.

Next, the electric valve according to the third embodiment of the present invention will be described with reference to FIGS. 6 to 8. The electric valve of the present embodiment includes a valve main body 1, a valve body 2, a valve holder 6, and a stepping motor 3 as a driving unit, similarly to the electric valve 10 of the first embodiment. In the electric valve of the present embodiment, the configurations of the valve body 2, the valve holder 6, and the rotor shaft 32 are different from those of the electric valve 10 of the first embodiment. The differences will be described in detail below.

In the electric valve of the present embodiment, as shown in FIG. 6, the rolling bearing 8 has a lower flange portion 32b and an upper flange portion 32d at the lower tip portion of the rotor shaft 32 as a shaft portion in the holder body 61. The first member 81 is attached to the outer peripheral portion of the reduced diameter portion 32c between the two. Further, a radial gap C1 of the rotor shaft 32 is provided between the second member 82 of the rolling bearing 8 and the inner surface of the holder body 61. Further, a ring-shaped protrusion 64 is provided in the middle portion of the inner surface of the holder body 61, and a gap C2 in the axis L direction is provided between the protrusion 64 and the lower surface of the rolling bearing 8. ing. Further, the upper end of the valve spring 9 is in contact with the lower surface of the protruding portion 64.

As shown in FIG. 6, when the valve is opened, the position of the axis L'of the rotor shaft 32 is shifted to the left side from the position of the axis L of the valve seat portion 13, for example. In order to bring the seated state, the valve body 2 is lowered by the drive of the stepping motor 3, and as shown in FIG. 7, when the needle portion 21 comes into contact with the valve seat portion 13, the axis L'of the valve body 2 is still present. Is offset to the left side of the position of the axis L of the valve seat portion 13 (valve port 14), and the left side of the needle portion 21 is in contact with the left side of the valve seat portion 13. At this time, a force as shown by an arrow (a force in the right direction in the radial direction and an upward force in the axis L direction) acts on the contact portion of the valve body 2 with the valve seat 13, and also acts on the valve holder 6. The force on the right side acts in the radial direction as shown by the arrow. When the rotor shaft 32 is further lowered, the ceiling surface of the holder body 61 supported by the valve body 2 and the valve spring 9 in the axis L direction and the upper end surface of the second member 82 of the rolling bearing 8 are separated from each other, and the rotor shaft 32 and the rolling bearing 8 are rolled. By moving the valve body 2 and the valve holder 6 to the right in the radial direction and upward in the axis L direction relative to the bearing 8, the holder body 61 is moved upward so as to reduce the gap C2 in the axis L direction. When seated, the axis L'of the valve body 2 and the axis L of the valve seat 13 are displaced to the right side where there is a radial gap C2 so that there is no radial deviation, and the rotation stopper mechanism 7 works. In, as shown in FIG. 8, the lower end portion of the rotor shaft 32 moves to the lower left relative to the valve holder 6 as compared with when the valve is opened, and the valve body 2 and the valve port 14 are coaxially above each other. Is located in.

According to the above embodiment, since the rolling bearing 8 is used as the bearing that connects the rotor shaft 32 and the valve holder 6 so as to be relatively rotatable, it is possible to suppress the rotation of the valve body 2 when the valve is closed, and the valve body 2 can be suppressed. Since the rotational load due to the sliding resistance between the valve seat 13 and the valve seat 13 is reduced, highly efficient operation can be achieved. Further, a radial gap C1 is provided between the rolling bearing 8 and the reduced diameter portion 32c of the rotor shaft 32, so that the rotor shaft 32 and the valve holder 6 can be displaced relative to each other in the radial direction. Since they are connected, when the valve body 2 is seated on the seating portion 13, the rotor shaft 32 and the holder body 61 of the valve holder 6 are displaced relative to each other in the radial direction only within the range of the gap C1 with respect to the valve seat portion 13. The valve body 2 can be seated coaxially, and valve leakage can be reduced.

Further, after the valve body 2 and the valve seat portion 13 come into contact with each other, the rotor shaft 32 further lowers, and when the valve body 2 is seated on the valve seat portion 13, the axis L'of the rotor shaft 32 and the valve port 14 Even if the axis L is deviated, the rotor shaft 32 and the valve holder 6 are displaced relative to each other in the radial direction and the axis L direction so that the valve body 2 can be seated coaxially with the valve seat portion 13. The needle portion 21 can come into contact with the entire circumference of the upper open end (valve seat portion 13) of the valve port 14 to reduce valve leakage. When the axis L'is displaced to the right side opposite to the drawing with respect to the axis L, the rotor shaft 32 has a gap C1 and C2 at the lower right when the valve body 2 is seated on the seating portion 13. Displace to the position of. In the embodiment of FIGS. 6 to 8, the first member 81 of the rolling bearing 8 and the rotor shaft 32 are attached to the lower flange portion 32b and the upper flange portion 32d of the first member 81 and the rotor shaft 32. In the example, a gap is provided in the direction of the axis L'of the rotor shaft 32, but between the first member 81 of the rolling bearing 8 and the lower flange portion 32b and the upper flange portion 32d of the rotor shaft 32. Even if there is no gap in the axis L'direction, the above effect can be obtained because the gap in the axis L direction is provided between the protruding portion 64 of the holder body 61 and the lower surface of the rolling bearing 8. It is self-evident.

Next, the electric valve according to the third embodiment of the present invention will be described with reference to FIG. The electric valve of the present embodiment includes a valve main body 1, a valve body 2, a valve holder 6, and a stepping motor 3 as a driving unit, similarly to the electric valve 10 of the first embodiment. In the electric valve of the present embodiment, a part of the valve holder 6 is different from the electric valve 10 of the first embodiment. The differences will be described in detail below.

In the electric valve of the present embodiment, there is no flange 32b at the lower end of the rotor shaft 32, there is no insertion hole 61a above the holder body 61 of the valve holder 6, and there is no lower end of the rotor shaft 32 and the upper surface of the holder body 61. The central portion of the valve body 2 is integrally formed, and most of the lower side of the rod shaft 22 of the valve body 2 is provided so as to be located outside the holder body 61. The second member 82 of the rolling bearing 8 is fixed to the inside of the holder body 61. The valve spring 9 is provided in a compressed state between the needle portion 21 of the valve body 2 and the ring-shaped spring receiving member 2a inserted in the middle of the rod shaft 22, and the valve body 2 faces downward with respect to the spring receiving member 2a. Being urged. The rod shaft 22 of the valve body 2 is inserted into the first member 81 of the rolling bearing 8, and the valve body 2 is supported so as to be displaceable along the axial direction L. Further, a radial gap C1 of the rod shaft 22 is provided between the rod shaft 22 and the first member 81 of the rolling bearing 8. Further, a gap C2 in the axis L direction of the rod shaft 22 is provided between the lower surface of the rolling bearing 8 and the upper surface of the spring receiver 2a. The spring receiving member 2a may be integrally formed with the valve body 2 without being a separate member.

In the electric valve of the present embodiment as described above, the same effect as that of the first embodiment can be obtained with respect to the correction for the deviation between the axial center of the valve body 2 and the axial line of the valve seat portion 13. In addition to this, in the valve holder 6, as in the electric valve of the second embodiment, the lower end portion of the rotor shaft 32 and the holder body 61 of the valve holder 6 are integrally formed, so that the first embodiment It is possible to simplify the configuration of this portion as compared with the electric valve 10 of the above.

Next, the refrigeration cycle system of the present invention will be described with reference to FIG. FIG. 8 is a diagram showing an example of the refrigeration cycle system of the present invention. In FIG. 8, reference numeral 100 is an expansion valve using the electric valve 10 of each of the above embodiments, 200 is an outdoor heat exchanger mounted on the outdoor unit, 300 is an indoor heat exchanger mounted on the indoor unit, 400. Is a flow path switching valve constituting a four-way valve, and 500 is a compressor. The electric valve 100, the outdoor heat exchanger 200, the indoor heat exchanger 300, the flow path switching valve 400, and the compressor 500 are each connected as shown by a conduit to form a heat pump type refrigeration cycle. The accumulator, pressure sensor, temperature sensor, etc. are not shown.

The flow path of the refrigeration cycle is switched between the flow path during the cooling operation and the flow path during the heating operation by the flow path switching valve 400. During the cooling operation, as shown by the solid line arrow in FIG. 8, the refrigerant compressed by the compressor 500 flows into the outdoor heat exchanger 200 from the flow path switching valve 400, and the outdoor heat exchanger 200 serves as a condenser. The liquid refrigerant that functions and flows out of the outdoor heat exchanger 200 flows into the indoor heat exchanger 300 via the expansion valve 100, and the indoor heat exchanger 300 functions as an evaporator.

On the other hand, during the heating operation, as shown by the broken arrow in FIG. 8, the refrigerant compressed by the compressor 500 flows from the flow path switching valve 400 to the indoor heat exchanger 300, the expansion valve 100, the outdoor heat exchanger 200, and the flow. The path switching valve 400 and the compressor 500 are circulated in this order, the indoor heat exchanger 300 functions as a condenser, and the outdoor heat exchanger 200 functions as an evaporator. The expansion valve 100 decompresses and expands the liquid refrigerant flowing from the outdoor heat exchanger 200 during the cooling operation and the liquid refrigerant flowing from the indoor heat exchanger 300 during the heating operation, and further controls the flow rate of the refrigerant. In FIG. 7, the liquid refrigerant flows from the outdoor heat exchanger 200 into the first joint pipe 101 of the expansion valve 100 during the cooling operation, and the liquid refrigerant from the indoor heat exchanger 300 flows into the expansion valve 100 during the heating operation. The expansion valve 100 is provided in the refrigeration cycle so as to flow into the second joint pipe 102 of the above, but the present invention is not limited to this, and the liquid refrigerant from the outdoor heat exchanger 200 during the cooling operation is the second joint of the expansion valve 100. The expansion valve 100 may be provided in the refrigeration cycle so that the liquid refrigerant flows into the pipe 102 and the liquid refrigerant from the indoor heat exchanger 300 flows into the first joint pipe 101 of the expansion valve 100 during the heating operation.

According to the above-mentioned refrigeration cycle system of the present invention, as described above, the electric valve 10 of the present embodiment can suppress valve leakage while improving efficiency, so that it saves energy during operation. Moreover, it is possible to provide a refrigeration cycle system in which defects are unlikely to occur.

As described above, the embodiments for carrying out the present invention have been described in detail with reference to the drawings based on the first to third embodiments, but the specific configuration is not limited to these embodiments and the gist of the present invention. Design changes that do not deviate from the above are included in the present invention.

For example, in the first to third embodiments described above, the electric valve 10 is used as an expansion valve of a refrigeration cycle system, but the present invention is not limited to this, and for example, a throttle device on the indoor unit side such as a multi air conditioner for a building or the like. , Can be applied to other systems.

10 Electric valve C1, C2 Gap 1 Valve body 1A Valve housing member 1C Valve chamber 2 Valve body 2a Spring receiving member 21 Needle part 22 Rod shaft (shaft part)
3 Stepping motor (drive unit)
6 Valve holder 61 Holder body 62 Spring receiver 8 Rolling bearing 81 1st member 82 2nd member 8a Steel ball (rolling member)
9 Valve spring 13 Valve seat 14 Valve port 32 Rotor shaft (rotary shaft, shaft)
100 Expansion valve 200 Outdoor heat exchanger (condenser, evaporator)
300 Indoor heat exchanger (condenser, evaporator)
400 Flow switching valve 500 Compressor

Claims (5)

The valve body constituting the valve chamber and the valve seat, the valve body that changes the opening degree of the valve port by contacting and separating from the valve seat in the axial direction, the drive unit that drives the rotating shaft to move forward and backward, and the valve body. An electric valve including a valve holder extending over the rotating shaft and a valve spring for urging the valve body in the valve closing direction.
At least one of the valve body and the rotating shaft has a shaft portion rotatably inserted into the valve holder, and a rolling bearing is provided between the shaft portion and the valve holder.
A radial gap is provided between the rolling bearing and at least one of the shaft portion and the valve holder, and the shaft portion and the valve holder can be displaced relative to each other in the radial direction. An electric valve characterized by being connected. A gap in the axial direction is provided between the rolling bearing and at least one of the shaft portion and the valve holder, and the shaft portion and the valve holder can be displaced relative to each other in the axial direction. The electric valve according to claim 1, wherein the electric valve is connected. The electric valve according to claim 1 or 2, wherein the shaft portion is a rod shaft of the valve body. The electric valve according to claim 1 or 2, wherein the shaft portion is a tip end portion of the rotating shaft. A refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the electric valve according to any one of claims 1 to 4 is used as the expansion valve. A refrigeration cycle system characterized by that.

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