JP2007255573A - Motor operated valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensively manufacturable motor operated valve capable of shortening the whole length of a can, miniaturizing a valve main body, stabilizing rotation of a rotor, and eliminating stress in the direction of rotation applied on a seat face of a valve seat by a valve element. <P>SOLUTION: Rotation of an insert metal 36 integrated with the rotor 30 is guided by fitting a cylindrical part 38 with bottom into a guide bush 26 to transmit stable rotation to a valve shaft holder 32. The insert metal 36 and the valve shaft holder 32 are mutually engaged so as to prevent their relative rotation due to different-shaped shaft parts fitted into different-shaped holes but so as to allow their relative rotation in the direction of axial line. The valve shaft holder 32 is moved in the direction of axial line by a screw feeding mechanism provided between the guide bush 26 and it when rotating. Moving of the valve shaft holder 32 in the direction of axial line is transmitted to the valve element 23 provided in a tip part of a valve shaft 24, and the valve element 23 comes into contact with the valve seat 22 or leaves the valve seat 22 to adjust flow rate of passing fluid. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor-operated valve used by being incorporated in an air conditioner, a refrigerator, or the like, and relates to a motor-operated valve that can achieve downsizing and noise reduction with a simple configuration.

  Conventionally, an electric valve used by being incorporated in this type of air conditioner, refrigerator, etc. is a device that adjusts the flow rate of a fluid such as a refrigerant, and usually includes a valve body having a valve chamber and a valve seat, A cylindrical can with a bottom fixed to the upper part of the valve body through a hook-shaped portion, and a rotor is built inside the can, and an insertion hole is formed in the center portion outside the can. The stator which has is externally fitted. One example of such an electric valve is disclosed in Patent Document 1.

  FIG. 4 is a longitudinal sectional view of the conventional motor-operated valve 1 as described above. The valve body 2 includes a valve chamber 2c, a guide bush fixing portion 2d, and a can fixing portion 2e. A fluid inflow pipe 2a and a fluid outflow pipe 2b through which a fluid such as a refrigerant enters and exits are provided, and a valve seat 2f to which a needle valve, which is a valve body 3a formed at the tip of the valve shaft 3, contacts and separates is disposed. It is installed.

  The guide bush fixing portion 2d is located above the valve chamber and fixes the valve body 2 and the guide bush 4 to each other. A male screw portion 4a is formed on the outer periphery of the guide bush 4, and a female screw portion 5a formed on the inner periphery of the valve shaft holder 5 is screwed to the male screw portion 4a. Is configured. And in the valve-shaft holder 5, the valve shaft 3 which forms the valve body 3a in the lower end part is inserted so that sliding is possible, and the valve shaft 3 is compression compressed by the valve-shaft holder 5 inside. The coil spring 3b is always biased downward.

  The can fixing portion 2e is located at the upper end of the valve body 2, and is composed of a ring-shaped metal plate whose inner peripheral surface is caulked and fixed, and whose lower end surface is joined by welding. The can 1 is fixed to the valve body 2 by being welded to the hook-shaped portion. The valve shaft 3 and the rotor 7 are coupled via a support ring 6. The support ring 6 is composed of a brass metal ring inserted when the rotor 7 is molded. The upper protrusion of the valve shaft holder 5 is fitted into the inner peripheral hole of the support ring 6, and the protrusion 7 is caulked and fixed to couple the rotor 7, the support piece 6 and the valve shaft holder 5. A push nut 3 c is press-fitted and fixed to the upper end of the valve shaft 3, and a cylindrical compression coil spring 3 d is attached to the outer periphery of the push nut 3 c so as to be loosely fitted or elastically contacted with the outer periphery of the guide bush 4. When the threaded engagement between the male threaded portion 4a and the female threaded portion 5a of the valve shaft holder 5 is disengaged, a force for returning to the threaded engagement can be applied. Further, the upper limit of the upward movement of the valve shaft 3 and the rotor 7 is given by the contact between the spring 3 d provided on the upper portion of the rotor 7 and the inner surface of the can 1. The upper stopper body 8 fixed to the valve shaft holder 5 and the lower stopper body 9 fixed to the guide bush 4 constitute a stopper mechanism for limiting the vertical stroke of the valve shaft 3.

  A rotor 7 is built in the can 1, and a stator (not shown) is fitted outside the can 1. A stator coil and a yoke are housed in the upper and lower portions inside the stator, and the stator coil is energized through a lead wire and a connector provided on the outer periphery of the stator. The yoke is excited by energizing the stator coil to rotate the rotor 7, and the valve shaft holder 5 and the valve shaft 3 are moved relative to each other by the screw feed mechanism, thereby opening and closing the valve body 3a to adjust the flow rate of the refrigerant. Is called.

  The structure related to the stator and the like is a structure well known in the technical field of the electric valve conventionally. For example, although not shown in detail, a metal ring-shaped mounting plate is fixed below the stator, and this mounting is performed. An anti-rotation piece formed integrally with the plate is engaged with a fluid inflow pipe 2a projecting horizontally from the valve body 2, and an engagement hole is formed on one side of the ring-shaped welded portion between the valve body 2 and the can 1. It is possible to employ a structure in which the stator is fixed by pressing the pressing piece formed integrally with the mounting plate on the other side of the ring-shaped welded portion.

  By the way, in the electric valve described above, the axial position of the valve shaft arranged inside the guide bush is changed by the action of the screw feed mechanism arranged outside the guide bush as the rotor rotates. As a result, the following phenomenon occurs. That is, since the axial position of the rotor changes with the opening and closing of the valve, the rotational force of the rotor applied by the electromagnetic action from the stator changes depending on the valve position and is not constant. Since the axial movement of the rotor must be allowed, the axial dimension of the motor-operated valve tends to be large, and the screw feed mechanism between the guide bush and the valve shaft holder is located below the rotor. The outer diameter of the valve body increases and becomes larger. Since the screw feed mechanism is positioned below the rotor and the rotor is rotationally driven by the screw feed mechanism arranged in such a manner, the rotor is likely to swing during rotation.

The above-described motor operated valve also has the following problem. That is, a collar or a spring is used for connection between the rotor and the valve shaft holder, which causes an increase in the number of parts. Further, the movement of the rotor in the axial direction is restricted by a stopper, but an impact sound is generated when the stopper comes into contact. Since the stopper mechanism for restricting the rotation of the rotor is similarly located below the rotor, a space is formed in the outer peripheral portions of 8 and 9 in FIG.
JP 2001-50415 A (paragraphs [0034] to [0038], FIG. 1)

  Therefore, by devising the insert metal that connects the rotor and guide bush, the rotation of the rotor is transmitted to the valve body via the valve shaft and drive mechanism arranged inside the guide bush, and the valve is opened and closed. At this time, there is a problem to be solved in terms of solving the above problems by adopting a structure in which the rotor does not move in the axial direction inside the can.

  The present invention has been made in consideration of such problems, and the object thereof is to reduce the overall length of the can and the valve body, stabilize the rotation of the rotor, and allow the valve body to be seated on the seat surface of the valve seat. Another object of the present invention is to provide a motor-operated valve that can eliminate the stress in the rotating direction and that can be manufactured at low cost without a stopper impact sound.

  In order to solve the above-described problems, the motor-operated valve according to the present invention includes a valve body that adjusts a passing flow rate by bringing a valve body provided at a distal end portion of a valve shaft into and out of contact with a valve seat in a valve chamber, and the valve A rotor built in the can attached to the main body and driven to rotate from the outside in order to bring the valve body into and out of contact with the valve seat, and a drive for converting the rotation of the rotor into a contact and separation operation of the valve shaft A drive bushing that extends from the valve main body side in the can in the can direction and is fixed to the rotor, and is integrated with the rotor and rotates to the guide bush. An insert metal to be guided, a valve shaft holder that is disposed in the guide bush and is non-rotatable relative to the insert metal, but is engaged so as to be relatively movable in the axial direction; It consists to have a screw feeding mechanism which converts the rotation from the rotor is provided between the id bushing and the valve shaft holder to move in the axial direction of the valve shaft holder.

  According to this motor-operated valve, when the valve is opened and closed, the rotor rotates without changing the axial position in the can due to the electromagnetic action from the stator. The rotation of the rotor is transmitted to the insert metal integrated with the rotor, and the rotation of the insert metal is engaged in the guide bush so as not to be relatively rotatable but to be relatively movable in the axial direction. It is transmitted to the holder. Since rotation of the insert metal is guided by the guide bush, stable rotation is transmitted to the valve shaft holder. When the valve shaft holder rotates, the valve shaft holder moves in the axial direction by a screw feed mechanism provided between the valve bush and the guide bush. At this time, since the valve shaft holder cannot rotate relative to the insert metal, the valve shaft holder rotates together with the insert metal but is engaged so as to be relatively movable in the axial direction, so that the position relative to the insert metal can be changed. The movement of the valve shaft holder in the axial direction is transmitted to the valve body provided at the tip of the valve shaft, and the valve body can be brought into contact with and separated from the valve seat in the room to adjust the passing flow rate.

  In the motor-operated valve, the insert metal is formed into a hat shape having a peripheral portion integrated with the rotor and a bottomed cylindrical portion connected to the peripheral portion, and the insert metal of the insert metal is formed in the bottomed cylindrical portion. The rotation can be guided by the guide bush. The insert metal is easily integrated with the rotor by casting the peripheral edge of the insert metal when the rotor is formed. Since the bottomed cylinder part of the insert metal is formed in a hat shape, the insert metal is rotated by a guide between the cylinder surfaces between the guide bush and the guide bush by fitting the cylinder surface to the cylinder surface of the guide bush. Guided stably.

  In the motor-operated valve, the valve shaft holder is configured such that a deformed shaft portion provided in the valve shaft holder is fitted into a deformed hole formed in the bottomed tube portion of the insert metal with respect to the insert metal. Can do. The deformed shaft portion of the valve shaft holder is fitted into the deformed hole formed in the bottomed tube portion of the insert metal, so that the insert metal and the bearing holder cannot be rotated relative to each other. It is transmitted to the shaft holder without idling. Further, since the valve shaft holder is engaged with the insert metal so as to be relatively movable, relative movement in the axial direction of the valve shaft holder with respect to the insert metal is allowed.

  In the above motor-operated valve, the insert metal can be disposed so as to be able to rotate and guide in a state where the cylindrical portion with the bottom is fitted into the guide bush. With such an arrangement, the outer peripheral surface of the bottomed cylindrical portion of the insert metal is guided to the inner peripheral surface of the guide bush.

  In the above motor-operated valve, the insert metal may be arranged so as to be able to rotate and guide in a state where the bottomed cylinder portion covers the outside of the guide bush. With such an arrangement, the inner peripheral surface of the bottomed cylindrical portion of the insert metal is guided to the outer peripheral surface of the guide bush.

  In the motor-operated valve described above, the valve shaft holder and the valve shaft are connected to each other via a guide coupling mechanism that guides within a range of a predetermined play stroke in the axial direction while being unconstrained in the rotational direction around the axial line. Can be connected. By connecting the valve shaft holder and the valve shaft via a guide connection mechanism that is not constrained in the rotational direction around the axis, the valve shaft holder is rotated when the valve shaft holder is rotated during opening / closing of the valve, particularly during the valve closing operation. The force is not transmitted to the valve shaft, and the stress generated between the valve body and the valve seat is reduced. Further, since this guide coupling mechanism guides the valve shaft holder and the valve shaft within the range of a predetermined play stroke in the axial direction, the axial direction is caused by the feeding action by the screw feeding mechanism when the valve shaft holder rotates. In the case of moving to, the stress generated between the valve seat and the valve seat is reduced within the range of the play stroke.

  In the motor-operated valve provided with the guide coupling mechanism, the guide coupling mechanism is provided in the valve shaft holder, and a spring that applies a biasing force that pushes the valve shaft toward the valve seat direction with respect to the valve shaft holder; A stopper for restricting the pushing out of the valve shaft, and a movement of the valve shaft in the direction of compressing the spring with respect to the valve shaft holder, and a smooth relative rotation of the valve shaft with respect to the valve shaft holder is permitted. And a ball. By providing this guide coupling mechanism, the valve shaft is always urged by a spring in a direction in which the valve element abuts on the valve seat, and movement is restricted by abutting on the valve seat. Even if the valve shaft holder is further pushed out after the valve body comes into contact with the valve seat, the valve shaft does not move, and only the valve shaft holder can advance while compressing the spring within the range of the play stroke. The movement of the valve shaft in the direction of retreating relative to the valve shaft holder while compressing the spring is limited by the ball. Since the ball is in contact with the valve shaft holder and the valve shaft, the friction acting between them is low friction, and the rotational force transmitted to the valve shaft can be substantially eliminated.

  In the motor-operated valve provided with the guide coupling mechanism, the guide coupling mechanism can be disposed below the valve shaft holder. In this case, the length of the valve shaft holder can be reduced by adopting a form in which the bottom portion of the insert metal is fitted into the guide bush from above, and as a result, contributes to miniaturization of the motor-operated valve. it can.

  In the motor-operated valve provided with the guide coupling mechanism, the guide coupling mechanism can be disposed on the valve shaft holder. In this case, the valve shaft holder needs to be long enough to accommodate the guide coupling mechanism. A combination of such an arrangement of the guide coupling mechanism and a form in which the bottom portion of the insert metal is turned up and the guide bush is covered with the insert metal from above is preferable because the axial length can be prevented from becoming too long. In this case, the valve shaft holder can secure the length of the guide portion that guides the valve shaft at the lower portion thereof.

  In each of the above motor-operated valves, the screw feeding mechanism includes a female screw portion formed in the guide bush and a male screw portion formed in the valve shaft holder and screwed into the female screw portion. It is preferable. The guide bush fixed to the valve body has a female threaded portion, and the valve shaft holder having a male threaded portion that engages with the female threaded portion moves in the axial direction while rotating by a screw feed action in the guide bush. Is possible.

  The drive mechanism for converting the rotation of the rotor to the movement of the valve body in the valve axis direction in order to perform the opening / closing operation of the valve is arranged in the can from the valve body side in the can. Guide bush extending in the direction and fixed, an insert metal integrated with the rotor and rotated and guided by the guide bush, and disposed in the guide bush and not rotatable relative to the insert metal, but of the valve shaft A valve shaft holder that is engaged so as to be relatively movable in the axial direction, and a screw feed mechanism that is provided between the guide bush and the valve shaft holder and converts rotation from the rotor into movement in the valve shaft direction of the valve shaft holder Therefore, there is no movement of the rotor in the axial direction as compared with a conventional electric valve having a structure in which the valve shaft holder is arranged outside the guide bush, and the insert metal. Rotation is guided by the guide bush, as a result, it is possible to stabilize the rotation of the rotor is possible reduce the size of the scan length and the valve body. In addition, since the stopper mechanism that allows the movement of the rotor in the axial direction but does not directly restrict the movement amount is not provided in the can, it is necessary to operate the stopper mechanism for setting the reference point for the pulse control of the rotor rotation. This eliminates the noise and eliminates the need for a space for providing the stopper mechanism, thereby reducing the size of the motor-operated valve. Furthermore, since the engagement between the insert metal and the guide bush is simplified and the number of parts is reduced, it is possible to provide an electric valve that can be manufactured at a low cost.

  Hereinafter, an embodiment of a motor-operated valve according to the present invention will be described in detail with reference to the accompanying drawings. 1A and 1B are views showing an embodiment of a motor-operated valve according to the present invention, in which FIG. 1A is a longitudinal sectional view thereof, and FIG. 1B is an end face showing one form of fitting between an insert metal and a valve shaft holder. FIG. The motor-operated valve 10 includes a valve body 20 that adjusts the flow rate of refrigerant through a valve body 23 that contacts and separates from a valve seat 22 in the valve chamber 21, and a rotor 30 that is fixed to the valve body 20 and contacts and separates the valve body 23. The can 40 is provided. Although not shown, the can 40 is fitted with a known stator that rotationally drives the rotor 30. The stator is composed of a yoke made of a magnetic material and upper and lower stator coils wound around the yoke via a bobbin, and is fitted on the can 40. The rotor 30 and the stator constitute a stepping motor as a drive source for performing the valve opening / closing operation of the electric valve 10. Further, a vertical fluid outflow pipe 20 a and a horizontal fluid inflow pipe 20 b are extended from the valve body 20.

  The can 40 has a bottomed cylindrical shape made of a non-magnetic metal such as stainless steel, and is fixed to a stainless steel flange 41 fixed to the upper part of the valve body 20 by welding or the like, and the inside is airtight. It is kept in. The valve body 23 has a needle valve structure at the lower end of a brass valve shaft 24. A driving mechanism for bringing the valve body 23 into contact with and separating from the valve seat 22 extends from the valve body 20 toward the rotor 30 and is fixed, and a cylindrical guide bush 26 in which a fixing screw portion 25 is formed, and a guide bush 26 It is a screw feed mechanism comprised from the valve-shaft holder 32 which has the moving screw part 31 screwed together to this fixed screw part 25.

  The fixing screw portion 25 is formed as a female screw portion on the lower inner periphery of the guide bush 26. Further, the moving screw portion 31 is formed as a male screw portion on the lower outer periphery of the valve shaft holder 32. The guide bush 26 and the valve shaft holder 32 are both formed from a brass cylindrical material.

  The rotor 30 and the valve shaft holder 32 are connected via an insert metal 36. In this embodiment, the insert metal 36 is formed from a single brass metal ring, and is inserted when the rotor 30 is formed. The insert metal 36 is formed into a hat shape having a ring-shaped peripheral edge portion 37 and a bottomed cylindrical portion 38 continuous with the peripheral edge portion 37. The insert metal 36 is integrated with the rotor 30 by casting the peripheral edge 37 of the insert metal 36 when the rotor 30 is formed. In the insert metal 36, the bottomed cylinder portion 38 is fitted to the upper portion of the guide bush 26, so that the rotation of the insert metal 36 is stably guided by the guide bush 26 when the rotor 30 rotates. In this example, the cylindrical outer surface of the bottomed cylindrical portion 38 is fitted from the upper end of the guide bush 26 and is fitted to the cylindrical inner surface.

  A non-circular shaped hole 39 is formed in the bottom portion 38 a of the bottomed tube portion 38 of the insert metal 36. The upper portion 33 of the valve shaft holder 32 is a deformed shaft portion that just fits into the deformed hole 39 of the insert metal 36. In this example, as shown in FIG. 1B, the upper portion 33 and the deformed hole 39, which are deformed shaft portions, are formed on flat surfaces 33a, 33a and 39a, 39a. When the insert metal 36 rotates due to the fitting engagement of the deformed shaft portion (upper portion 33) and the deformed hole 39, the valve shaft holder 32 also rotates together with the valve shaft holder 32 in the axial direction with respect to the insert metal 36. Can be moved relative to each other. Therefore, the rotation of the insert metal 36 is transmitted to the valve shaft holder 32 without idling, and the valve shaft holder 32 moves relative to the insert metal 36 in the direction along the valve axis while rotating by the screw feed mechanism. Can do.

  The valve main body 20, the valve shaft 24, the guide bush 26, the valve shaft holder 32, and the insert metal 36 are all made of brass as described above, and are configured in consideration of recycling. Furthermore, since the parts are inserted and screwed together except for the insert metal 36, each part can be reused by releasing the fitting between the valve shaft holder 32 and the guide bush 26, for example. . Of course, metals other than brass, such as stainless steel, can be used. Of course, metals other than brass, such as stainless steel, can be used only for the valve shaft 24.

  In the motor-operated valve 10, a guide coupling mechanism 50 that guides the valve shaft 24 and the valve shaft holder 32 within a range of a predetermined play stroke in the axial direction while being unconstrained in the rotational direction around the axial line. It is connected through. In this example, the guide coupling mechanism 50 is disposed in the lower portion 34 of the valve shaft holder 32. The lower portion 34 of the valve shaft holder 32 is a cylindrical cavity opened downward, and the upper portion of the valve shaft 24 and the guide coupling mechanism 50 are accommodated in the cavity. The moving screw portion 31 is formed on the outer peripheral surface of the lower portion 34 as described above. The valve shaft 24 having the valve body 23 formed at the lower end is made of brass, and is inserted into the center of the valve shaft holder 32 so as to be movable up and down.

  The guide coupling mechanism 50 is provided on the valve shaft holder 32 and a compression coil spring 51 that applies a biasing force that pushes the valve shaft 24 downward with respect to the valve shaft holder 32, that is, toward the valve seat 22. A stopper 52 for restricting the downward movement of the valve shaft 24 and a compression coil spring 51 for restricting the movement in the compression direction with respect to the valve shaft holder 32 of the valve shaft 24 and smoothing the valve shaft 24 with respect to the valve shaft holder 32 And a ball 53 that allows relative rotation. The stopper 52 is formed by caulking the cylindrical lower end edge of the valve shaft holder 32. The stopper 52 also serves to prevent the valve shaft 24 from coming off from the valve shaft holder 32. By providing the guide coupling mechanism 50, the valve shaft 24 is always urged in the valve closing direction by the compression coil spring 51, and the intermediate flange portion of the valve shaft 24 abuts against the stopper 52 so that the valve The amount of movement of the shaft 24 in the valve closing direction is limited. After the valve element 23 comes into contact with the valve seat 22, the valve shaft 24 can be retracted relative to the valve shaft holder 32 while compressing the spring 51 within the range of the idle stroke. This backward movement of the valve shaft 24 is limited by the ball 53 coming into contact with the valve shaft holder 32 and the valve shaft 24. Since the contact of the ball 53 with the valve shaft holder 32 and the valve shaft 24 is rolling, the friction acting between them is low friction, and when the valve shaft holder 32 is rotated by the rotor 30, the valve shaft 24 is rotated. The force in the rotational direction transmitted to the can be substantially eliminated.

  By connecting the valve shaft 24 and the valve shaft holder 32 via the guide connection mechanism 50, the valve shaft 24 and the valve shaft holder 32 are unconstrained in the rotational direction around the axis, and the valve is opened and closed, particularly the valve is closed. When the valve shaft holder 32 is rotated during operation, the rotational force is hardly transmitted to the valve shaft 24, and the stress generated between the valve body 23 and the valve seat 22 is reduced or eliminated. Further, the guide coupling mechanism 50 guides the valve shaft holder 32 and the valve shaft 24 within the range of a predetermined play stroke in the axial direction. Accordingly, when the valve shaft holder 32 rotates in the axial direction due to the feeding action by the screw feeding mechanism, the stress generated between the valve body 23 and the valve seat 22 is only in a range limited as an idle stroke. Acts and avoids any excessive stress.

  The valve body 20 is made of a metal such as brass, and is joined to the can 40 by butt welding the end of the can 40 to the stepped portion of the bowl-like plate 41 fixed to the valve body 20 by welding or the like. Yes. Not only butt welding, but also the end of the can 40 may be bent flat on the outer periphery to form a bowl-like part, and the bowl-like part and the bowl-like plate 41 may be fixed by so-called worship welding.

  The operation of the motor-operated valve 10 configured as described above will be described. In the valve open state in which the valve body 23 is separated from the valve seat 22, in the guide coupling mechanism 50, the valve shaft 24 abuts against the stopper 52 by the action of the compression coil spring 51 and the position of the ball 53 is restricted. The valve shaft 24 and the valve shaft holder 32 are not in contact with each other at the same time. When a stator coil (not shown) is energized and excited in one direction, the rotor 30, the insert metal 36, and the valve shaft holder 32 are rotated with respect to the guide bush 26 fixed to the valve body 20, and the fixing screw portion 25 of the guide bush 26. For example, the valve shaft holder 32 is moved downward by the screw feed mechanism between the moving screw portion 31 of the valve shaft holder 32 and the valve body 23 formed at the tip of the valve shaft 24 via the guide coupling mechanism 50 is a valve. The valve opening is closed by being pressed against the seat 22.

  When the rotor 30 continues to rotate while the valve body 23 remains closed, the valve shaft holder 32 further rotates and descends. Since the valve shaft holder 32 is lowered with respect to the valve shaft 24 in contact with the valve seat 22, the downward movement of the valve shaft holder 32 is absorbed by the compression coil spring 51 being compressed. As the rotation of the rotor 30 progresses, the ball 53 simultaneously contacts both the valve shaft 24 and the valve shaft holder 32, so that the lowering of the valve shaft holder 32 is forcibly stopped even when energization of the stator is continued. . Note that the rotation amount of the rotor 30 that determines the movement amount limit of the valve shaft holder 32 is controlled by the pulse number control of the stepping motor.

  The ball 53 performs a stopper function by simultaneously contacting both the valve shaft 24 and the valve shaft holder 32. The ball 53 is disposed within the entire cavity in the axial direction of the rotor 30 as an element of the guide coupling mechanism 50 in the cavity in the valve shaft holder 32, but the insert metal 36 is fitted to the guide bush 26. In addition, since the valve shaft holder 32 is guided to the guide bush 26 at the upper part even during its rotation, the rotor 30 and the valve shaft holder 32 are less likely to be greatly inclined, and the valve opening / closing operation is stabilized.

  When the stator coil is energized in the other direction and excited, the rotor 30, the insert metal 36 and the valve shaft holder 32 are rotated in the opposite direction to the guide bush 26 fixed to the valve body 20, and the fixing screw of the guide bush 26 is fixed. The valve shaft holder 32 moves upward by a screw feed mechanism between the portion 25 and the moving screw portion 31 of the valve shaft holder 32. By this movement of the valve shaft holder 32, the valve body 23 at the lower end of the valve shaft 24 is separated from the valve seat 22, the valve port is opened, and the refrigerant can pass through the valve port. And the passage amount of a refrigerant | coolant can be adjusted with the rotation amount of the rotor 30, and since the rotation amount of the rotor 30 is regulated by the number of pulses, an exact adjustment can be performed.

  Thus, the rotor 30 rotates, and the rotor 30, the insert metal 36, the valve shaft holder 32, and the valve shaft 24 are moved by the screw feed mechanism of the fixed screw portion 25 of the guide bush 26 and the moving screw portion 31 of the valve shaft holder 32. Although it slides in the axial direction, the rotor 30 rotates, but does not move in the axial direction. Therefore, the rotational force of the pulse motor is stably constant by the electromagnetic action from the stator. Further, since the insert metal 36 is fitted to the guide bush 26 so as to be able to rotate and guide, the rotor 30 does not swing during rotation and can be stably rotated.

  FIG. 2 shows another example of the fitting structure between the deformed hole formed in the bottom portion 38 a of the insert metal 36 and the deformed shaft portion formed in the upper portion 33 of the valve shaft holder 32. . In the example shown in FIG. 2A, a rectangular hole 59a is formed as a deformed hole in the bottom portion 38a. In this case, the deformed shaft portion formed on the upper portion 33 of the valve shaft holder 32 is a shaft portion having a rectangular cross section that fits into the rectangular hole 59a. In the example shown in FIG. 2B, a D-shaped hole 59b is formed as a deformed hole in the bottom portion 38a. Also in this case, the deformed shaft portion of the valve shaft holder 32 is a D-shaped shaft that fits into the D-shaped hole 59b. Further, in the example shown in FIG. 2 (c), an uneven hole 59c is formed as a deformed hole in the bottom portion 38a. The deformed shaft portion of the valve shaft holder 32 is a concave / convex shaft in which the concave / convex hole 59c fits.

  Next, another embodiment of the present invention will be described. FIG. 3 is a longitudinal sectional view of another embodiment of the electric valve according to the present invention. This embodiment is different from the above-described embodiment with respect to the arrangement of the insert metal and the guide coupling mechanism 50, so this point will be described in detail, and other substantially equivalent configurations will be denoted by the same reference numerals. Detailed description will be omitted.

  In the motor-operated valve 60 shown in FIG. 3, the insert metal 76 is in a state in which the bottomed cylinder part 78 faces upward and the bottomed cylinder part 78 covers the outside of the guide bush 66. Therefore, the inner peripheral surface of the insert metal 76 is rotationally guided by the outer peripheral surface of the guide bush 66. Since the space inside the upper portion of the guide bush 66 is vacated by this arrangement of the insert metal 76, the guide coupling mechanism 80 provided in the valve shaft holder 32 is arranged using this space. That is, the guide coupling mechanism 80 is disposed above the position where the screw feeding mechanism is provided. The structure of the guide coupling mechanism 80 itself is, as compared with the guide coupling mechanism 50, a collar 81 that is mounted in a groove formed around the valve shaft 24 as a member that supports the spring force of the compression coil spring 51. There is no change except.

  In the valve shaft holder 32, a moving screw portion 31 that is screwed with the fixing screw portion 25 of the guide bush 66 is formed, but the distal end side cylinder portion 82 in which the moving screw portion 31 is formed as a male screw portion is cylindrical. The valve shaft 24 is guided by the inner surface. With this structure, the axial movement of the valve shaft 24 is guided by the insert metal 76 in the upper portion and the distal end side cylindrical portion 82 of the guide bush 66 in the middle portion, so that the inclination of the valve shaft 24 is prevented. And smooth valve opening / closing operation. As described above, the axial length and the outer diameter of the valve body 20 can be greatly reduced as compared with the conventional motor-operated valve in which the screw feed mechanism is located below the rotor. 60 can be downsized.

It is a figure which shows one Embodiment of the motor operated valve which concerns on this invention. In the electric valve which concerns on this invention, it is an end elevation which shows another form of a fitting with an insert metal and a valve stem holder. It is a figure which shows another embodiment of the motor operated valve which concerns on this invention. It is a longitudinal cross-sectional view which shows an example of the conventional motor operated valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Motorized valve 20 Valve body 20a Fluid outflow pipe 20b Fluid inflow pipe 21 Valve chamber 22 Valve seat 23 Valve body 24 Valve shaft 25 Fixing screw part 26 Guide bush 30 Rotor 31 Moving screw part 32 Valve shaft holder 33 Upper part 34 Lower part 33a, 33a Flat surface 36 Insert metal 37 Peripheral part 38 Bottomed cylindrical part
38a Bottom part 39 Profile hole
39a, 39a Flat surface 40 Can 41 Gutter-shaped plate 50 Guide connection mechanism 51 Compression coil spring 52 Stopper 53 Ball 59a Rectangular hole 59b D-shaped hole 59c Uneven hole 60 Motorized valve 66 Guide bush 76 Insert metal 78 Bottom cylinder part 80 Guide connection Mechanism 81 Collar 82 Tip side cylinder

Claims (10)

  A valve body that adjusts a passing flow rate by bringing a valve body provided at a tip portion of the valve shaft into and out of contact with a valve seat in the valve chamber; and a valve body that is built in a can attached to the valve body and the valve A rotor that is rotationally driven from the outside to bring the body into and out of contact with the valve seat; and a drive mechanism that converts the rotation of the rotor into a contact and separation operation of the valve shaft. A guide bush extending from the valve body side in the rotor arrangement direction and fixed; an insert metal integrated with the rotor and rotatably guided by the guide bush; and disposed in the guide bush. A valve shaft holder engaged with the insert metal so as not to rotate relative to the insert metal but relatively movable in the axial direction; and provided between the guide bush and the valve shaft holder. Electric valve consists of and a feed screw mechanism for converting rotation from over data on the movement of the axial direction of the valve shaft holder.   The insert metal is formed into a hat shape having a peripheral portion integrated with the rotor and a bottomed cylindrical portion continuous to the peripheral portion, and the rotation of the insert metal in the bottomed cylindrical portion is the guide bush. The motor-operated valve according to claim 1, wherein the motor-operated valve is guided by the valve.   The valve shaft holder is engaged with the insert metal by fitting a deformed shaft portion provided in the valve shaft holder into a deformed hole formed in the bottomed tube portion of the insert metal. The motor-operated valve according to claim 2, comprising:   4. The motor-operated valve according to claim 2, wherein the insert metal is disposed so as to be able to rotate and guide in a state in which the bottomed cylindrical portion is fitted into the guide bush.   4. The motor-operated valve according to claim 2, wherein the insert metal is rotationally guided on an outer peripheral surface in a state in which the bottomed cylinder portion covers an outer side of the guide bush.   The valve shaft holder and the valve shaft are coupled via a guide coupling mechanism that guides within a range of a predetermined play stroke in the axial direction without restriction in the rotational direction around the axis. The motor operated valve according to any one of claims 1 to 5.   The guide coupling mechanism includes a spring that applies an urging force that pushes the valve shaft toward the valve seat holder in the valve seat direction, and a stopper that is provided on the valve shaft holder and restricts the pushing of the valve shaft. And a ball that restricts movement of the valve shaft in the direction of compressing the spring with respect to the valve shaft holder and allows smooth relative rotation of the valve shaft with respect to the valve shaft holder. 6. The motor operated valve according to 6.   The motor-operated valve according to claim 6 or 7, wherein the guide coupling mechanism is disposed at a lower portion of the valve shaft holder.   The motor-operated valve according to claim 6 or 7, wherein the guide coupling mechanism is disposed on an upper portion of the valve shaft holder.   The said screw feed mechanism is comprised from the internal thread part currently formed in the said guide bush, and the external thread part currently formed in the said valve shaft holder and screwing together with the said internal thread part. The motor operated valve according to any one of 9.

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