JP2008175289A - Motor operated valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor operated valve capable of lessening driving torque in valve opening, simplifying the construction, reducing the number of parts and the device cost, etc. by reducing friction resistance between the components members. <P>SOLUTION: A valve element 61 has a base element 61A for seating in a valve seat 72b and a collar-shaped latch member 66 which is fitted on a small-diameter shaft part 61c of the base element 61A for axial relative movement and relative rotation and is engaged by a tubular engagement part 63 provided on a valve holder 55 to support a lower end part of a compression coil spring 64, wherein when the valve holder 55 is at the lowermost position, a lower surface of the collar-shaped latch member 66 is in pressure contact with an upper end terrace surface of a large-diameter shaft portion 61b of the base element 61A and a gap α is formed between the lower surface of the collar-shaped latch member 66 and an upper end surface of the cylindrical engagement part 63, when a rotor 30 and the valve holder 55 rotate from the lowermost position, the upper end surface of the cylindrical engagement part 63 contacts with the lower surface of the collar-shaped latch member 66 and the collar-shaped latch member 66 separates from the upper end terrace surface of the large-diameter shaft portion 61b and when the rotor 30 and the valve holder 55 further rotate, the collar-shaped latch member 66 pushes up a flange part 61d. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor-operated valve, and more particularly to a stepping motor-driven motor-operated valve that is used as a flow control valve or the like in a refrigeration cycle such as an air conditioner or a refrigerator.

  As an electric valve used by being incorporated in an air conditioner, a refrigerator, or the like, a valve as shown in FIG. 6 is considered by the inventors of the present application.

  The motor-operated valve 10 ′ shown in FIG. 6 includes a valve body 70 having a valve chamber 71. The valve body 70 includes a valve seat member 72 having a valve opening 72a having a circular cross section and a conical valve seat 72b, and a cylindrical valve chamber forming member 74 with a can receiving collar portion 74a. The lower end portion 40b of the bottomed cylindrical can 40 having a lower opening is sealed and joined to the can receiving rod-shaped portion 74a of the forming member 74 by butt welding. The flow rate of the fluid is adjusted.

  A refrigerant inlet / outlet first conduit (joint) 41 is provided on one side of the valve chamber 71 of the valve body 70, and a refrigerant inlet / outlet second conduit (joint) is provided below the valve chamber 71. 42 are connected and fixed by brazing or the like.

  A rotor 30 is arranged on the inner periphery of the can 40 with a predetermined gap. Although not shown on the outer periphery of the can 40 to rotate the rotor 30, a yoke, a bobbin, and A stator composed of a stator coil or the like is disposed, and the rotor 30 and the stator constitute a stepping motor.

  On the inner peripheral side of the rotor 30, there is a valve shaft 60 integrally connected to the rotor 30 via a nut member 62, and a guide stem 80 having a cylindrical portion 81 into which the valve shaft 60 is inserted. Is distributed.

  At the lower end of the cylindrical portion 81 of the guide stem 80, a concave connection holding portion 82 used for positioning for increasing the coaxiality between the valve main body 70 and the can 40 is integrally provided.

  On the other hand, the upper end portion of the cylindrical valve holder 55 is press-fitted and fixed to the lower end portion of the large diameter of the valve shaft 60. The valve holder 55 is held and fixed to the valve shaft 60 and is slidably inserted into the cylindrical portion 81 of the guide stem 80.

  The valve shaft 60, the valve holder 55, the valve body 61 and the like are configured as one assembly (hereinafter referred to as a valve shaft assembly 50), and the valve body 61 is attached to the valve shaft 60 at the lower end portion of the valve holder 55. The shaft is inserted so as to be capable of relative movement and rotation in the axial direction, and is latched and locked by a cylindrical locking portion 63 described later.

  The valve body 61 is locked by a base 61A having a conical valve portion 61a seated on the valve seat 72b, and a cylindrical locking portion 63 that is fixed to the lower end portion of the valve holder 55 by a technique such as press-fitting or welding. The base 61A includes a hook-like hooking member 66 which is a separate part. The base body 61A of the valve body 60 has, in order from the bottom, a conical valve portion 61a, a body portion 61b having a diameter smaller than the outer diameter of the upper portion (bottom surface portion) of the conical valve portion 61a, and a diameter smaller than the outer diameter of the body portion 61b. The outer diameter of the upper portion (bottom surface portion) of the conical valve portion 61a on the upper end surface (the terrace surface formed between the cylindrical portion 61c) of the trunk portion 61b, which has a caulking portion (being a cylindrical portion) 61c. A hook-shaped hooking member 66 having a smaller outer diameter and formed in a ring shape having a rectangular cross section is fixed by caulking the cylindrical portion 61c. The hook-shaped hooking member 66 also serves as a spring receiver that receives the lower end of the coil spring 64.

  A spring receiving ball 65 is disposed on the lower side of the valve shaft 60 in the valve holder 55, and between the spring receiving ball 65 and the valve body 61, a valve cutoff for urging the valve body 61 downward is provided. A compression coil spring 64 for buffering is also mounted.

  In addition to the above, a screw feed mechanism 16 for bringing the valve body 61 into and out of contact with the valve seat 72b is provided. The screw feed mechanism 16 is a female screw that is internally fitted and fixed to the cylindrical portion 81 of the guide stem 80. A fixed screw portion (female screw portion) 28 formed on the inner periphery of the member 85 and a movable screw portion (male screw portion) 29 formed on the outer periphery of the central portion of the valve shaft 60 and screwed into the fixed screw portion 28. It is made up of.

  Therefore, in the motor-operated valve 10 having such a configuration, when the rotor 30 is rotated, the valve shaft 60 (valve shaft assembly 50) is rotated integrally therewith. At this time, the valve shaft 60 is moved by the screw feed mechanism 16 to the valve shaft 60. The body 61 is moved up and down, thereby adjusting the flow rate of the refrigerant.

  Further, a fixed stopper 68 and a movable stopper (slider) 69 constituting a rotation restricting stopper mechanism are fitted on the outer periphery of the guide stem 80. Each of the fixed stopper 68 and the movable stopper 69 is composed of a coil spring (a wire material spirally bent) (details will be described in an embodiment described later).

  In the motor-operated valve 10 ′ having such a configuration, the rotor 30 and the valve shaft assembly 50 are rotated in one direction and fixed by energizing and exciting (pulse supply) the stator in the first mode. By a screw feed mechanism 16 comprising a screw portion (female screw portion) 28 and a movable screw portion (male screw portion) 29, the valve shaft assembly 50 moves downward, the valve body 61 is seated on the valve seat 72b, and the valve port 72a is Closed.

  When the valve port 72a is closed, the end surface contact portion 69b of the movable stopper 69 is not yet in contact with the lower end locking portion (not shown) of the fixed stopper 68, and the valve body 61 closes the valve port 72a. The rotor 30, the valve shaft 60, and the valve holder 55 are further rotated and lowered. At this time, the valve shaft 60 and the valve holder 55 are lowered while integrally rotating with respect to the valve body 61, so that the compression coil spring 64 is further compressed, whereby the lowering force of the valve shaft 60 and the valve holder 55 is reduced. When the valve body 61 is pressed against the valve seat 72b and then the rotor 30 is further rotated, the end surface contact portion 69b of the movable stopper 69 becomes the lower end locking portion (not shown) of the fixed stopper 68. ), The valve shaft 60 and the valve holder 55 reach the lowest lowered position, and even if the pulse supply to the stator is continued, the lowering of the valve shaft 60 and the valve holder 55 is forcibly stopped and the valve is closed (fully closed). State).

  Here, when the valve shaft 60 and the valve holder 55 are in the lowest lowered position (fully closed state) as shown in FIGS. 6 and 7A, the valve element is applied by the biasing force of the compression coil spring 64. 61 is strongly pressed against the valve seat 72b via the hook-shaped hooking member 66. At this time, as shown in FIG. 7A, the lower end surface of the hook-shaped hooking member 66 and the cylindrical locking portion 63 are pressed. A predetermined gap α is formed between the upper end surface.

  On the other hand, when the stator is energized and excited (pulse supply) in the second mode from this fully closed state, the rotor 30 and the valve shaft assembly 50 are rotated in the opposite direction to the above, and the fixed screw portion (female screw portion) 28 and The valve shaft 60 and the valve holder 55 are now moved upward while rotating with respect to the valve body 61 by the screw feed mechanism 16 including the movable screw portion (male screw portion) 29. Here, since there is a predetermined gap α between the lower end surface of the hook-shaped latching member 66 and the upper end surface of the cylindrical locking portion 63, the valve shaft 60 and the valve holder 55 are located from the lowest position. When the fixed amount is rotated, as shown in FIG. 7B, the lower end surface of the hook-shaped hooking member 66 and the upper end surface of the cylindrical locking portion 63 abut. When the valve shaft 60 and the valve holder 55 are further rotated and raised from this contact point, the valve body 61 is pulled up and the valve is opened while the cylindrical locking portion 63 engages the hook-like hooking member 66.

  However, when the valve is opened (immediately before the valve element 61 is pulled up), the valve element 61 is strongly pressed against the valve seat 72b by the urging force of the compression coil spring 64 and is in an immobile state (a large frictional resistance). Since the hook-shaped hooking member 66 integral with the valve body 61 is sandwiched between the lower end portion of the compression coil spring 64 and the upper end portion of the cylindrical locking portion 63, the valve shaft 60 and the valve holder 55 are rotated up. When doing so, a large frictional resistance is generated between the hook-shaped hooking member 66, the compression coil spring 64, and the cylindrical locking portion 63.

  By the way, in this type of electric valve, in order to be able to cope with an increase in capacity and the like under a compact configuration without causing an increase in the size of the entire electric valve including the stepping motor, It is important to reduce the frictional resistance, particularly the frictional resistance from the fully closed state where the largest driving torque is required until the valve is opened, to reduce the driving torque required for valve opening.

  However, in the motor-operated valve 10 ′, a large frictional resistance is generated when the valve that requires the largest driving torque is opened. Therefore, a stepping motor having a large output torque, that is, a large and expensive one is used. In addition, there is a problem that power consumption increases.

  In order to reduce the frictional resistance when the valve is opened as described above, the following Patent Document 1 describes an electric valve having the following configuration. In addition, the code | symbol with the parenthesis in the following explanatory notes is a thing of the said literature 1.

  That is, the valve holder (20) has a lower member (21) having a lower lip piece (21A), an upper member (22) having an upper lip piece (22A), a lower member (21), and an upper member ( 22), and the valve body (30) is provided with a flange portion (30A) corresponding to the hook-shaped hooking member 66, and the valve body (30). When the lower spring retainer member (25) that receives the lower end of the compression coil spring (29) is loosely fitted to the upper portion of the body (30) and the valve holder (20) is rotated by a predetermined amount from the lowest position, the stopper When the body (23) comes into contact with the lower spring retainer member (25) and the valve holder (20) is further rotated and raised from this contact point, the stopper body (23) biases the compression coil spring (29). The lower spring retainer member ( 5) raise.

In this case, since the valve holder (20), the compression coil spring (29), and the lower spring retainer member (25) rotate integrally, there is substantially no frictional resistance between them, and the lower side By pulling up the spring retainer member (25), the valve body (30) is separated from the valve holder (20), and the valve body (30) is substantially seated on the valve seat (13) only by its own weight. . Thereafter, when the valve holder (20) is further rotated and raised, the valve body (30) is pulled up and opened with the lower lip piece (21A) engaging the flange portion (30A).
JP 2006-207852 A

  However, the motor-operated valve described in Patent Document 1 can reduce the frictional resistance between the constituent members when the valve is opened, but the configuration of the valve holder is complicated, the number of parts is large, the manufacturing is troublesome, and the device cost is low. There was a dislike of becoming high.

  In addition, since the flange (ring-shaped hooking member) is provided integrally with the valve body, the outer diameter of the valve holder is relatively large relative to the diameter of the valve port (valve seat). A large frictional resistance is generated between the guide stem and the guide stem. The larger the frictional resistance, the greater the driving force required for opening and closing the valve. Therefore, a stepping motor with a large output torque, that is, a large and expensive one, must be used, and the power consumption is large. Become.

  In this case, the frictional resistance increases as the outer diameter of the valve holder increases. However, in the conventional general electric valve, the diameter of the valve port (valve seat) is the same as that described in Patent Document 1. On the other hand, the outer diameter of the valve holder was relatively large. That is, as shown in FIG. 5B, the upper (bottom) outer diameter Da ′ of the conical valve portion 61a ′ of the valve body 61 ′ is substantially equal to the upper (bottom) diameter of the valve seat 72b of the valve seat member 72. Although having the same diameter, the valve body 61 ′ is outside the upper part (bottom surface) of the conical valve part 61a ′ so as to be retained and locked to a cylindrical locking part 63 ′ provided in the valve holder 55 ′. It is necessary to provide a hook-shaped hook 61e ′ having an outer diameter Db ′ that is considerably larger than the diameter Da ′, and the outer diameter Dc ′ of the valve holder 55 ′ is inevitably increased. Therefore, the frictional resistance between the valve holder and the guide stem is large.

  The present invention has been made in view of such circumstances. The object of the present invention is to reduce the frictional resistance between the constituent members and reduce the driving torque required for opening the valve. Simplification, reduction of the number of parts, etc., and the cost of the apparatus can be kept low, so that the entire motor-operated valve including the stepping motor is not increased in size, and it is large in a compact configuration. An object of the present invention is to provide an electric valve adapted to cope with capacity increase.

  In order to achieve the above object, an electric valve according to the present invention includes a can, a guide stem having a cylindrical portion disposed in the can, a rotor disposed on the inner periphery of the can, and the rotor. A connected and fixed valve shaft; a cylindrical valve holder provided at a lower end portion of the valve shaft and inserted in a cylindrical portion of the guide stem; and the valve holder in an axial direction with respect to the valve shaft. The upper part of the valve holder is inserted in a state where it can be relatively moved and rotated, and is urged downward by a compression coil spring that is compressed between the valve shaft and provided at the lower end of the valve holder. And a valve body having a valve chamber in which fluid is allowed to enter and exit, and a valve seat to which the valve body comes into contact with and separated from the valve body. A screw feed mechanism for making contact with and separating from the valve seat.

  The valve body includes a base provided with a conical valve portion, a large diameter shaft portion, a small diameter shaft portion, and a flange portion that are seated on the valve seat sequentially from below, and a shaft disposed on the small diameter shaft portion of the base body. A hook-shaped hook that is externally fitted so as to be capable of relative movement and rotation in a direction, is locked by a locking portion provided in the valve holder, and receives the lower end of the compression coil spring. And when the valve holder is in the lowest lowered position, the lower surface of the hook-shaped hooking member is in pressure contact with the upper terrace surface of the large-diameter shaft portion of the base, and the hook-shaped hooking member When a predetermined gap is formed between the lower surface and the upper end surface of the locking portion, and the rotor and the valve holder are rotated by a predetermined amount from the lowest position, the upper end surface of the locking portion is hooked. The hook-shaped hooking member is in contact with the lower surface of the stopper member, and the upper-end terrace of the large-diameter shaft portion Spaced from, then, when the rotor and the valve holder is further rotated, the flange-shaped locking member is characterized in that it is as to lift the flange portion.

  Preferably, the base body includes a body portion having the conical valve portion and a large diameter shaft portion, and a flanged pin fixed to the large diameter shaft portion by press-fitting or the like.

  The hook-shaped hooking member is preferably manufactured in a ring shape having an outer diameter smaller than the outer diameter of the upper bottom surface portion of the conical valve portion.

  In the motor-operated valve of the present invention, when the valve holder is in the lowest lowered position (fully closed state), the bottom surface of the hook-shaped hooking member is pressed against the upper terrace surface of the large-diameter shaft portion of the base, and the hook-shaped When a predetermined gap is formed between the lower surface of the latch member and the upper end surface of the locking portion, and the rotor and the valve holder are rotated by a predetermined amount from the lowest position, the upper end surface of the locking portion is When the hook-shaped hooking member comes into contact with the lower surface of the hook-shaped hooking member and is separated from the upper end terrace surface of the large-diameter shaft portion, and then the rotor and the valve holder are further rotated, Since the hook-shaped hooking member pushes up the flange portion, when the valve is opened (when the spring receiving member is pushed up) when the greatest driving torque is required, the hook-shaped hooking member is removed from the valve body. The valve body is substantially seated on the valve seat with its own weight only. The state. At this time, since the valve holder, the compression coil spring, and the hook-shaped latching member rotate integrally, a frictional resistance is not substantially generated between them.

  In other words, in the conventional motor-operated valve, when the valve is opened (when the valve body is pulled up), the valve body is strongly pressed against the valve seat by the urging force of the compression coil spring and is brought into an immobile state (high frictional resistance). Yes, since the hook-shaped latching member integral with the valve body is sandwiched between the lower end portion of the compression coil spring and the upper end portion of the cylindrical locking portion, when rotating the valve shaft and the valve holder, Although a large frictional resistance is generated between the hook-shaped hooking member, the compression coil spring, and the cylindrical locking portion, in the motor-operated valve of the present invention, the valve body (base) is separated from the hook-shaped hooking member and the valve holder. Therefore, there is substantially no frictional resistance between them.

  Therefore, the frictional resistance between the constituent members at the time of opening the valve can be greatly reduced, and the driving torque required at the time of opening the valve can be reduced. As a result, the entire electric valve including the stepping motor is not enlarged. It is possible to cope with an increase in capacity under a compact configuration.

  Moreover, since the hook-shaped hooking member also serves as a spring receiving member that receives the lower end portion of the compression coil spring, the structure can be simplified, the number of parts can be reduced, and the apparatus cost can be kept low. Can do.

  Furthermore, when assembling the valve body, the base body having the conical valve portion constituting the valve body and the hook-shaped hooking member locked by the locking portion provided in the valve holder are separated. For example, the locking portion is extrapolated to a trunk portion (large diameter shaft portion) connected to the conical valve portion so as to be relatively movable and relatively rotatable, and a small diameter shaft portion and a flange portion are configured on the large diameter shaft portion. When the flanged pin is press-fitted and fixed, the conical valve portion 61a of the valve body 61 is formed by fitting the hook-shaped hooking member to the small-diameter shaft portion as illustrated in FIG. The upper (bottom) outer diameter Da is substantially the same as the upper (bottom) diameter of the valve seat 72b of the valve seat member 72, as in the conventional example illustrated in FIG. The outer diameter Db of the hook-shaped hooking member 66 (corresponding to the hook-shaped hooking portion 61e 'of the conventional example) is the same as that of the conventional hook-shaped hooking portion 61e'. Can considerably smaller than db '(upper portion of the conical valve portion 61a of the valve body 61 (which can be equal to or smaller than the bottom) outer diameter Da). Therefore, the outer diameter Dc of the valve holder 55 can be made considerably smaller than the conventional one (Dc ′). As a result, the frictional resistance generated between the valve holder and the guide stem can be greatly reduced, and the operation Noise can also be effectively suppressed.

  As a result, the driving force required for the valve opening / closing operation can be further reduced, and the entire motor-operated valve including the stepping motor can be reduced in size and power can be effectively reduced.

Hereinafter, embodiments of the motor-operated valve of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing an embodiment of an electric valve according to the present invention.
The motor-operated valve 10 shown in FIG. 1 includes a valve body 70 having a valve chamber 71. The valve body 70 includes a valve seat member 72 having a valve opening 72a having a circular cross section and a conical surface valve seat 72b, a cylindrical valve chamber forming member 74 with a can receiving collar portion 74a produced by pressing, The flow rate of a fluid such as a refrigerant is adjusted by a valve body 61 that contacts and separates from the valve seat 72b. The valve seat member 72 has a bottom portion with a window hole of the valve chamber forming member 74 fixed thereto by press fitting, welding or the like. Further, the lower end portion 40b of the bottomed cylindrical can 40 having a lower opening is sealed and joined to the can receiving collar portion 74a of the valve chamber forming member 74 by butt welding.

  A refrigerant inlet / outlet first conduit (joint) 41 is provided on one side of the valve chamber 71 of the valve body 70, and a refrigerant inlet / outlet second conduit (joint) is provided below the valve chamber 71. 42 are connected and fixed by brazing or the like.

  A rotor 30 is arranged on the inner periphery of the can 40 with a predetermined gap. Although not shown on the outer periphery of the can 40 to rotate the rotor 30, a yoke, a bobbin, and A stator composed of a stator coil or the like is disposed, and the rotor 30 and the stator constitute a stepping motor.

  On the inner peripheral side of the rotor 30, there is a valve shaft 60 integrally connected to the rotor 30 via a nut member 62, and a guide stem 80 having a cylindrical portion 81 into which the valve shaft 60 is inserted. Is distributed.

  At the lower end of the cylindrical portion 81 of the guide stem 80, a concave connection holding portion 82 used for positioning for increasing the coaxiality between the valve main body 70 and the can 40 is integrally provided.

  On the other hand, the upper end portion of the cylindrical valve holder 55 is press-fitted and fixed to the lower end portion of the large diameter of the valve shaft 60. The valve holder 55 is held and fixed to the valve shaft 60 and is slidably inserted into the cylindrical portion 81 of the guide stem 80.

  The valve shaft 60, the valve holder 55, the valve body 61 and the like are configured as one assembly (hereinafter referred to as a valve shaft assembly 50), and the valve body 61 is attached to the valve shaft 60 at the lower end portion of the valve holder 55. The shaft is inserted so as to be capable of relative movement and rotation in the axial direction, and is latched and locked by a cylindrical locking portion 63 described later.

  The valve body 61 includes a base 61A provided with a conical valve portion 61a, a large-diameter shaft portion 61b, a small-diameter shaft portion 61c, and a flange portion 61d that are seated on the valve seat 72b sequentially from the bottom, and the small-diameter of the base body 61A. The shaft 61c is externally fitted in a state in which it can be relatively moved and rotated in the axial direction, is locked by a cylindrical locking portion 63 provided in the valve holder 55, and the compression coil spring 64 And a hook-shaped hooking member 66 adapted to serve as a spring receiver for receiving the lower end portion.

  The base 61A is a flanged pin 61B having a trunk portion including a conical valve portion 61a and a large-diameter shaft portion 61b, and a small-diameter shaft portion 61c and a flange portion 61d that are fixed to the large-diameter shaft portion 61b by press-fitting or the like. It consists of and.

  Further, the hook-shaped latching member 66 is formed in a ring shape having an outer diameter smaller than the outer diameter of the upper portion (bottom surface portion) of the conical valve portion 61a, and the upper end terrace surface of the large-diameter shaft portion 61b. It can be moved relative to the flange portion 61d in the axial direction by a predetermined gap β (see FIG. 2A).

  And this hook-shaped latching member 66 is latched and locked by the cylindrical latching part 63 fixed to the lower end part of the valve holder 55 by press-fitting, welding or the like. A spring receiving ball 65 is disposed below the valve shaft 60 in the valve holder 55, and the valve body 61 is urged downward between the spring receiving ball 65 and the hook-shaped hooking member 66. A compression coil spring 64 for valve closing and buffering is mounted.

  In the motor-operated valve 10 according to this embodiment, before the valve body 61 is assembled to the valve holder 55, a locking portion provided in the valve holder 55 in advance to lock the valve body 61 to the body portion 61b. The cylindrical locking portion 63 is extrapolated so as to be capable of relative movement and rotation, and the cylindrical locking portion 63 is welded to the valve holder 55 when the valve body 61 is assembled to the valve holder 55. It is fixed by a method such as caulking or press fitting.

  In addition to the above, a screw feed mechanism 16 for bringing the valve body 61 into and out of contact with the valve seat 72b is provided. The screw feed mechanism 16 is a female screw that is internally fitted and fixed to the cylindrical portion 81 of the guide stem 80. A fixed screw portion (female screw portion) 28 formed on the inner periphery of the member 85, and a movable screw portion (screw threaded on the fixed screw portion 28 formed on the outer periphery of the central portion of the valve shaft 60 of the valve shaft 60). Male threaded portion) 29.

  Therefore, in the motor-operated valve 10 having such a configuration, when the rotor 30 is rotated, the valve shaft 60 (valve shaft assembly 50) is rotated integrally therewith. At this time, the valve shaft 60 is moved by the screw feed mechanism 16 to the valve shaft 60. The body 61 is moved up and down, thereby adjusting the flow rate of the refrigerant.

  Further, a fixed stopper 68 and a movable stopper (slider) 69 constituting a rotation restricting stopper mechanism are fitted on the outer periphery of the guide stem 80. As shown in FIG. 3 (A), the fixed stopper 68 is a coil spring (having a spiral winding of wire) having an effective number of turns of 5.5 (5 and a half turns) and a right winding direction. The portion is an upper locking portion 68a bent upward from the spiral portion, and the lower end thereof is a lower locking portion 68b bent downward from the spiral portion. Further, as shown in FIG. 3 (B), the movable stopper 69 is a coil spring having a valid winding number of 1.5 (one and a half turns) and a winding direction on the right (a spirally wound wire). The upper end portion is a side protruding contact portion 69a bent sideways from the spiral portion, and the lower end (end) of the spiral portion is an end surface contact portion 69b formed on a flat surface.

  The diameter of the wire that is the material of the movable stopper 69 is slightly larger than the diameter of the wire that is the material of the fixed stopper 68, but the pitch of the movable stopper 69 and the pitch of the fixed stopper 68 are the same. The fixed stopper 68 (the lower locking portion 68b) is fixed to the connection holding portion 82 (the bottom portion) of the guide stem 80, and the movable stopper 69 is incorporated in the spiral portion of the fixed stopper 68 as shown in FIG. It can be moved up and down while rotating along the spiral portion.

  The side protrusion contact portion 69a of the movable stopper 69 is pushed by a vertically long push plate portion 39 that protrudes from the inner periphery of the rotor 30 when the rotor 30 rotates (both forward and reverse). It has come to be. Therefore, when the rotor 30 is rotated clockwise in a plan view, the movable stopper 69 is lowered while rotating in the same direction, and finally, the position where it is most lowered in FIG. 4 is indicated by a solid line. The end surface abutting portion 69b is abutted against and locked to the lower locking portion 68b of the fixed stopper 68, whereby the rotation and lowering of the rotor 30 are forcibly stopped. When the rotor is rotated counterclockwise in plan view, the movable stopper 69 rises while rotating in the same direction, and finally, the most elevated position in FIG. The side protrusion contact portion 69a is brought into contact with and locked to the upper locking portion 68a of the fixed stopper 68, whereby the rotation and ascent of the rotor 30 are forcibly stopped.

  In the motor-operated valve 10 according to the present embodiment having such a configuration, the rotor 30 and the valve shaft assembly 50 are rotated in one direction by energizing and exciting the stator in the first mode (pulse supply). The valve shaft assembly 50 is moved downward by the screw feed mechanism 16 including the fixed screw portion (female screw portion) 28 and the movable screw portion (male screw portion) 29, and the valve body 61 is seated on the valve seat 72b. The mouth 72a is closed.

  When the valve port 72a is closed, the movable stopper 69 is not yet in contact with the fixed stopper 68, and the rotor 30, the valve shaft 60, and the valve holder 55 further rotate while the valve body 61 closes the valve port 72a. Descend. At this time, the valve shaft 60 and the valve holder 55 are lowered while integrally rotating with respect to the valve body 61, so that the compression coil spring 64 is further compressed, whereby the lowering force of the valve shaft 60 and the valve holder 55 is reduced. When the valve body 61 is pressed against the valve seat 72b and then the rotor 30 is further rotated, the end surface contact portion 69b of the movable stopper 69 strikes the lower locking portion 68b of the fixed stopper 68. In contact with each other, the valve shaft 60 and the valve holder 55 reach the lowest lowered position, and even if the pulse supply to the stator is continued, the lowering of the valve shaft 60 and the valve holder 55 is forcibly stopped, and the valve is closed (fully closed). Become.

  Here, when the valve shaft 60 and the valve holder 55 are in the lowest lowered position (fully closed state) as shown in FIGS. 1 and 2A, the valve element is urged by the urging force of the compression coil spring 64. 61 is strongly pressed against the valve seat 72b via the hook-shaped hooking member 66. At this time, as shown in FIG. 2 (A), the upper surface of the hook-shaped hooking member 66 and the cylindrical locking portion 63 are A predetermined gap α is formed between the end surface.

  On the other hand, when the stator is energized and excited (pulse supply) in the second mode from this fully closed state, the rotor 30 and the valve shaft assembly 50 are rotated in the opposite direction to the above, and the fixed screw portion (female screw portion) 28 and The valve shaft 60 and the valve holder 55 are now moved upward while rotating with respect to the valve body 61 by the screw feed mechanism 16 including the movable screw portion (male screw portion) 29. Here, since there is a predetermined gap α between the lower surface of the hook-shaped hooking member 66 and the upper end surface of the cylindrical locking portion 63, the valve shaft 60 and the valve holder 55 are moved from the lowest position by a predetermined amount. When rotated, as shown in FIG. 2 (B), the lower surface of the hook-shaped hooking member 66 and the upper end surface of the cylindrical locking portion 63 are in contact with each other. When 55 is further rotated and raised, as shown in FIG. 2 (C), the valve body 61 is pulled up with the cylindrical locking portion 63 hooking the hook-shaped hooking member 66, and the hook-shaped hooking is performed. The member 66 is separated from the upper end terrace surface of the large-diameter shaft portion 61b, and the valve body 61 is separated from the valve seat 72b and opened.

  Here, at the time of valve opening when the largest driving torque is required (when the hook-shaped hooking member 66 is pulled up), the hook-shaped hooking member 66 is separated from the valve body 61, and the valve body 61 is substantially Therefore, it is in a state of being seated on the valve seat 72b only by its own weight. At this time, since the valve holder 55, the compression coil spring 64, and the hook-shaped latching member 66 rotate integrally, frictional resistance is not substantially generated between them.

  That is, in the above-described conventional motor-operated valve 10 ′, when the valve is opened (immediately before the valve body 61 is pulled up), the valve body 61 is strongly pressed against the valve seat 72b by the urging force of the compression coil spring 64 and does not move. In this state (the frictional resistance is large), and the hook-shaped hooking member 66 integral with the valve body 61 is sandwiched between the lower end portion of the compression coil spring 64 and the upper end portion of the cylindrical locking portion 63. When the valve shaft 60 and the valve holder 55 are rotated and raised, a large frictional resistance is generated between the hook-shaped hooking member 66, the compression coil spring 64, and the cylindrical locking portion 63. 10, the valve body 61 (base 61 </ b> A) is separated from the hook-shaped hooking member 66 and the valve holder 55, so that substantially no frictional resistance is generated between them.

  Therefore, the frictional resistance between the constituent members at the time of opening the valve can be greatly reduced, and the driving torque required at the time of opening the valve can be reduced. As a result, the entire electric valve including the stepping motor is not enlarged. It is possible to cope with an increase in capacity under a compact configuration.

  Further, since the hook-shaped hooking member 66 also serves as a spring receiving member that receives the lower end portion of the compression coil spring 64, the structure can be simplified, the number of parts can be reduced, and the apparatus cost can be reduced. Can be suppressed.

  Furthermore, the base 61A having the conical valve portion 61a constituting the valve body 61 and the hook-like hooking member 66 locked by the cylindrical locking portion 63 provided in the valve holder 55 are separated. Thus, when assembling the valve body 61, for example, the cylindrical locking portion 63 is extrapolated to a barrel portion (large diameter shaft portion 61b) connected to the conical valve portion 61a so as to be relatively movable and relatively rotatable. When the flanged pin 61B constituting the small diameter shaft portion 61c and the flange portion 61d is press-fitted and fixed to the diameter shaft portion 61b, the hook-shaped hooking member 66 is externally fitted to the small diameter shaft portion 61c. As illustrated in FIG. 5A, the upper (bottom) outer diameter Da of the conical valve portion 61a of the valve body 61 is similar to that of the conventional example illustrated in FIG. 72 is the same diameter as the upper (bottom) diameter of the valve seat 72b, but is hooked The outer diameter Db of the material 66 (corresponding to the conventional hook-shaped hook 61e ′) can be made considerably smaller than the outer diameter Db ′ of the conventional example (the hook-shaped hook 61e ′) (the conical valve portion of the valve body 61). (It can be equal to or less than the upper (bottom) outer diameter Da of 61a). Therefore, the outer diameter Dc of the valve holder 55 can be made considerably smaller than the conventional one (Dc ′). As a result, the frictional resistance generated between the valve holder 55 and the guide stem 80 can be greatly reduced. The operation noise can also be effectively suppressed.

  As a result, the driving force required for the valve opening / closing operation can be further reduced, and the entire motor-operated valve including the stepping motor can be reduced in size and power can be effectively reduced.

The longitudinal cross-sectional view of the principal part except the stator of one Embodiment of the electrically operated valve which concerns on this invention. The principal part expanded sectional view with which operation | movement description of the motor operated valve shown by FIG. 1 is provided. The figure which shows the fixed stopper (A) and movable stopper (B) which comprise the stopper mechanism for rotation control of the electrically operated valve shown in FIG. The figure which is provided for operation | movement description of the stopper mechanism for rotation control shown by FIG. The valve-shaft assembly part of a motor operated valve is shown, (A) is the thing of embodiment shown by FIG. 1, (B) is a thing of a prior art example. The longitudinal cross-sectional view of the principal part which shows an example of the conventional motor operated valve. The principal part expanded sectional view with which operation | movement description of the motor operated valve shown by FIG. 6 is provided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electric valve 16 Screw feed mechanism 30 Rotor 28 Fixed screw part 29 Movable screw part 40 Can 50 Valve shaft assembly 55 Valve holder 60 Valve shaft 61 Valve body 61A Base 61B Flange pin 61a Conical valve portion 61b Body (Large diameter shaft) Part)
61c Small-diameter shaft portion 61d Flange portion 63 Cylindrical locking portion 64 Buffer coil spring 66 Hook-shaped hooking member 70 Valve body 71 Valve chamber 72 Valve seat member 72a Valve port 72b Valve seat 74 Valve chamber forming member 80 Guide stem 81 Cylinder Part

Claims (3)

A can, a guide stem having a cylindrical portion disposed in the can, a rotor disposed on the inner periphery of the can, a valve shaft connected and fixed to the rotor, and a lower end portion of the valve shaft A cylindrical valve holder inserted into the cylindrical portion of the guide stem, and an upper portion of the valve holder is inserted into the valve holder in a state in which relative movement and relative rotation are possible in the axial direction with respect to the valve shaft, And a valve body that is biased downward by a compression coil spring that is compressed between the valve shaft and that is retained by a retaining portion provided at a lower end portion of the valve holder, and a fluid. A valve body having a valve chamber that allows the valve body to enter and exit, a valve body that contacts and separates the valve body, and a screw feed mechanism that causes the valve body to contact and separate from the valve seat as the rotor rotates. A motorized valve,
The valve body includes a base body provided with a conical valve portion, a large diameter shaft portion, a small diameter shaft portion, and a flange portion that are seated on the valve seat in order from the bottom, and an axial direction on the small diameter shaft portion of the base body. A hook-shaped latching member that is fitted in a state that allows relative movement and relative rotation, is latched by a latching portion provided in the valve holder, and receives a lower end portion of the compression coil spring. And
When the valve holder is in the lowest lowered position, the lower surface of the hook-shaped hooking member is pressed against the upper end terrace surface of the large-diameter shaft portion of the base, and the lower surface of the hook-shaped hooking member and the locking portion are When a predetermined gap is formed between the upper end surface and the rotor and the valve holder are rotated by a predetermined amount from the lowest position, the upper end surface of the locking portion contacts the lower surface of the hook-shaped hooking member. Then, when the hook-shaped hooking member is separated from the upper end terrace surface of the large-diameter shaft portion and then the rotor and the valve holder are further rotated, the hook-shaped hooking member pushes up the flange portion. A motor-operated valve characterized in that   The said base | substrate is comprised by the trunk | drum which has the said conical valve part and a large diameter shaft part, and the pin with a flange fixed to the said large diameter shaft part by press injection etc., The Claim 1 characterized by the above-mentioned. Motorized valve.   The motor-operated valve according to claim 1 or 2, wherein the hook-shaped hooking member is formed in a ring shape having an outer diameter smaller than the outer diameter of the upper bottom surface portion of the conical valve portion.

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