JP5087150B2 - Motorized valve - Google Patents

Description

  The present invention relates to an electric valve used by being incorporated in an air conditioner, a refrigerator, or the like, and in particular, high coaxiality can be ensured for rotating system components (rotor, valve body, can, valve shaft, guide member, etc.). In addition, the present invention relates to a motor-operated valve that can reduce frictional resistance generated between them as much as possible.

  As an electric valve used by being incorporated in an air conditioner, a refrigerator, or the like, for example, as seen in the following Patent Document 1 or the like, a valve shaft having a valve body and a valve having a valve seat on which the valve body contacts and separates A main body, a can joined to the valve main body, a rotor disposed on the inner periphery of the can, a stator disposed on the outer periphery of the can for rotationally driving the rotor, and held and fixed to the valve main body. A guide member having a cylindrical portion that guides the valve shaft, and a screw feed mechanism that is disposed between the rotor and the valve body and contacts and separates the valve body from the valve seat using the rotation of the rotor. Is known.

  In this electric valve, the screw feed mechanism includes a fixed screw portion formed on the outer periphery of the guide member, and a movable screw portion formed on the inner periphery of the valve shaft holder disposed on the outer periphery of the valve shaft and the guide member. It is configured.

  In addition, as another electric valve, a valve shaft is connected to a rotor so as to be integrally rotatable and integrally movable, and the valve shaft and the valve body are separated from each other, for example, as shown in Patent Document 2 below. Known to. In this type of electric valve, for example, a cylindrical valve holder is attached to the lower part of the valve shaft, and a separate valve body (upper part) is moved relative to the valve shaft in the axial direction and relative to the valve shaft. A screw feed mechanism that is inserted in a rotatable state and locked to prevent the valve body from contacting and separating from the valve seat is formed, for example, on the inner periphery of a female screw member attached to the guide member. And a movable screw portion formed on the outer periphery of the valve shaft.

JP 2001-50415 A JP 2003-329158 A

  In the conventional motorized valve as described above, the rotor, the valve body, the can, the valve shaft, the guide member, the valve holder, etc., which are rotating system components, ensure high coaxiality, that is, their rotational axis or central axis. If there is a need to make sure that each axis does not coincide with a common axis, and if sufficient coaxiality cannot be obtained, the can and rotor rub against each other, or the valve shaft and guide The frictional resistance of the sliding contact portion between the member or the valve holder and the guide member is increased, and the operation performance, durability performance, and the like are lowered.

  The present invention has been made in view of such circumstances. The object of the present invention is to provide a rotor, a valve body, a can, a valve shaft, a guide member, a valve holder, and a rotation regulating member that are rotating system components. It is an object of the present invention to provide a motor-operated valve capable of ensuring high coaxiality in a stopper or the like and reducing frictional resistance generated between them as much as possible.

  In order to achieve the above object, an electric valve according to the present invention is basically held and fixed to a valve shaft, a guide stem having a cylindrical portion into which the valve shaft is inserted, and a lower end portion of the valve shaft. A cylindrical valve holder inserted into the guide stem, and a valve that is inserted into the valve holder in a state in which it can be relatively moved and rotated in the axial direction with respect to the valve shaft, and that is prevented from coming off. Body, a valve main body having a valve seat to which the valve body contacts and separates, a can joined to the valve main body, a rotor disposed on the inner periphery of the can, and the can to rotate the rotor The valve body comprising: a stator disposed on an outer periphery of the valve; a fixed screw portion formed on an inner periphery of a female screw member attached to the guide stem; and a movable screw portion formed on an outer periphery of the valve shaft. A screw feed mechanism for contacting and separating the valve seat.

  The valve shaft is provided with a flange-shaped guide portion having an outer diameter smaller than the inner diameter of the cylindrical portion of the guide stem, and the outer diameter of the valve holder is made smaller than the outer diameter of the flange-shaped guide portion. It is characterized by being.

  In a preferred embodiment, the upper end of the valve holder is caulked and fixed to the lower end of the valve shaft.

  In the motor-operated valve according to the present invention, the required concentricity can be obtained for the rotor, the valve body, the can, the valve shaft, the guide stem, the valve holder, the rotation regulating stopper and the like constituting the rotating system.

  In addition, a guide stem having an outer diameter smaller than the inner diameter of the cylindrical portion of the guide stem is provided on the valve shaft, and the outer diameter of the valve holder is made smaller than the outer diameter of the guide guide portion. And the valve holder are prevented from interfering with each other, and even if the assembly accuracy of the valve holder to the valve shaft and the coaxiality thereof are low, the operation performance, durability performance, etc. can be prevented from being adversely affected.

The longitudinal cross-sectional view which shows the reference example relevant to the motor operated valve which concerns on this invention. The elements on larger scale of the valve main body periphery shown by FIG. 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. 1, FIG. The enlarged view (B) of the same part of an enlarged view (A) of one Embodiment which concerns on this invention which shows the connection part of the valve shaft shown in FIG. 1 and a valve holder, and a comparative example. The figure used for description of the jig | tool used for the welding joining of the upper collar part of a guide stem, and the can receiving collar part of a valve chamber formation member. The figure used for description of the welding joining of an upper hook-shaped part and a can receiving hook-shaped part in the case of forming an annular protrusion on the lower surface of the upper hook-shaped part of the guide stem. The figure used for description of the welding joining of an upper side hook-shaped part and a can receiving hook-shaped part at the time of forming a convex protrusion in some places on the lower surface of the upper side hook-shaped part of a guide stem. The figure which is provided to description of the welding joining of an upper side hook-shaped part and a can receiving hook-shaped part in the case where convex protrusion is formed in some places on the upper surface of the can receiving hook-shaped part of a valve chamber forming member.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a reference example related to the electric valve according to the present invention. The motor-operated valve 10 related to the present invention includes a valve body 70 having a valve chamber 71 and a valve seat member 72 (valve port 72a). The valve body 70 is composed of a valve seat member 72 having a valve opening 72a made by cutting, and a cylindrical valve chamber forming member 74 with a can receiving collar portion 74a made by pressing, The valve body 61 that contacts and separates from the valve seat 72 adjusts the flow rate of fluid such as refrigerant. A cylindrical lower end portion of the valve chamber forming member 74 is fixed to the valve seat member 72 by press fitting, welding, or the like. Thereby, high coaxiality is obtained between the valve seat member 72 and the valve chamber forming member 74. And the lower end part 40b of the bottomed cylindrical can 40 having a lower opening is sealed and joined to the can receiving collar part 74a of the valve chamber forming member 74 by butt welding (welded part K) (detailed later). ).

  A first conduit 41 for refrigerant entry / exit is provided on one side of the valve chamber 71 of the valve body 70, and a second conduit 42 for refrigerant entry / exit is brazed on the lower side of the valve chamber 71. It is connected and fixed by.

  A rotor 30 is disposed on the inner periphery of the can 40 with a predetermined gap. A yoke 51, a bobbin 52, and stator coils 53, 53 are disposed on the outer periphery of the can 40 so as to rotationally drive the rotor 30. The rotor 50 and the stator 50 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, 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 connection holding portion 82 used for positioning for increasing the coaxiality between the valve main body 70 and the can 40 is integrally provided. As shown in an enlarged view in FIG. 2, the connection holding portion 82 is placed on a cylindrical portion 82b and a can receiving hook-shaped portion 74a that are fitted into the inner periphery of the valve chamber forming member 74 of the valve body 70. A bottomed cylindrical shape with a hook-shaped portion is formed of an upper flange-shaped portion 82 a welded and a bottom portion 82 c connected to the cylindrical portion 81.

  On the lower surface of the upper hook-shaped portion 82a of the connection holding portion 82 (or the upper surface of the can-receiving hook-shaped portion 74a), protrusions 82e are formed at several locations for convenience of welding. In joining the connection holding portion 82 to the valve chamber forming member 74, the cylindrical portion 82b of the connection holding portion 82 is fitted (press-fitted) into the inner periphery of the valve chamber forming member 74, and on the can receiving collar 74a. The upper hook-like portion 82a of the connection holding portion 82 is placed and pressed (the protrusion 82e is bitten), and welding, for example, projection welding, is performed in a pressurized state. As a result, the valve chamber forming member 74 (valve body 70) and the connection holding portion 82 (guide stem 80) are joined with high coaxiality.

  Furthermore, in the motor-operated valve related to the present invention, the outer diameter of the upper hook-like portion 82a of the connection holding portion 82 is smaller than the outer diameter of the can-receiving hook-like portion 74a of the valve chamber forming member 74. The lower end portion 40b of the can 40 is hermetically joined by butt welding (welded portion K) to the stepped portion 73 formed by the flange portion 74a and the upper flange portion 82a. Thereby, not only between the center axis of the can 40 and the center axis of the valve seat member 72, the valve chamber forming member 74, and the connection holding portion 82 constituting the valve body 70, but also between the center axis of the guide stem 80. There is almost no deviation, and there is almost no deviation between the valve shaft 60 inserted in the guide member 80 and the axis of the rotor 30, and all the members constituting the rotating system have high coaxiality (common) Axis A).

  On the other hand, in the motor operated valve of the present embodiment, as shown in FIG. 5A, the lower end portion of the valve shaft 60 is used for holding and fixing for caulking and fixing the upper end portion 90a of the cylindrical valve holder 90. A hook-shaped portion 63b and an annular groove 63c are provided, and a hook-shaped guide portion 63a having an outer diameter larger than that of the holding and fixing hook-shaped portion 63b is provided thereon (details will be described later). The valve holder 90 is held and fixed to the valve shaft 60 and is inserted into the cylindrical portion 81 of the guide stem 80, and the valve body 61 (the hook-shaped latching portion 61 c) is attached to the valve shaft 60. On the other hand, it is inserted so as to be capable of relative movement and relative rotation in the axial direction. The valve body 61 includes a truncated cone portion 61b seated on the valve seat member 72 and a short shaft valve stem portion 61a integrally connected to the truncated cone portion 61b, and is provided on the upper portion of the valve stem portion 61a. The hook-shaped hooking portion 61c is locked to the lower end bent portion 90b of the valve holder 90 to prevent it from coming off. In the valve holder 90, a buffer coil spring 64 for biasing the valve body 61 downward via the ball 65 is mounted.

  Further, a screw feed mechanism 16 for bringing the valve body 61 into and out of contact with the valve seat member 72 is provided, and the screw feed mechanism 16 is fitted and fixed to an upper portion of a guide stem 80 made of a cylindrical tube. The fixed screw portion 28 is formed on the inner periphery of the female screw member 85, and the movable screw portion 29 is formed on the outer periphery of the central portion of the valve shaft 60 and is screwed to the fixed screw portion 28.

  Therefore, in the motor-operated valve 10 of the present embodiment, when the rotor 30 is rotated, the valve shaft 60 is rotated integrally therewith. At this time, the valve shaft 60 is moved up and down with the valve body 61 by the screw feed mechanism 16. Thus, the flow rate of the refrigerant is adjusted.

  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. 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 82c) of the guide stem 80, and the movable stopper 69 is attached to the spiral portion of the fixed stopper 68 as shown in FIG. It is built in and can move up and down while rotating along its spiral portion.

  The side protrusion contact portion 69a of the movable stopper 69 is pushed by a vertically long push plate 39 projecting from the inner periphery of the rotor 30 when the rotor 30 rotates (both forward and reverse). It has become so. 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 of the present embodiment configured as described above, the guide stem 80 is integrally provided with a connection holding portion 82 that is used for positioning to increase the coaxiality of the valve main body 70 and the can 40. Therefore, the required concentricity can be obtained for the rotor 30, the valve main body 70, the can 40, the valve shaft 60, the guide stem 80, the valve holder 90, the rotation restricting stoppers 68 and 69, etc. constituting the rotating system.

  In particular, the valve body 70 has a bottomed cylindrical shape with a can receiving collar portion 74a, the connection holding portion 82 of the guide stem 80 is a cylindrical portion 82b that is inserted into the inner periphery of the valve body, and the valve body 70 has a can receiving collar shape. A cylindrical shape with a hook-like portion comprising an upper hook-like portion 82a that is placed on the portion 74a and is welded and a bottom portion 82c that is connected to the cylindrical portion 81, and is further connected to the can receiving hook-like portion 74a. By connecting the lower end portion 40b of the can 40 to the stepped portion 73 formed by the holding member 82 by butt welding, the rotation axis lines of all the members forming the rotation system and the guide stem 80 are used as a reference. The center axis can be hardly displaced, and high coaxiality (common axis O) can be secured to them, thereby reducing the frictional resistance generated at the sliding contact portion of the rotating system component. Is, as a result, to improve the operating performance and durability performance and the like.

  In the present embodiment, as shown in FIG. 5A, a flange-shaped guide portion 63a having an outer diameter Da smaller than the inner diameter Dc of the cylindrical portion 81 of the guide stem 80 is provided at the lower end portion of the valve shaft 60. The outer diameter Db of the valve holder 90 is made smaller than the outer diameter Da of the hook-shaped guide portion 63a, and the valve holder 90 and the valve holder 90 are separated from the gap α formed between the hook-shaped guide portion 63a and the guide stem 80. The gap β formed between the guide stem 80 and the guide stem 80 is made larger. In this case, as shown in FIG. 5B, the outer diameter Da of the hook-shaped portion 63a ′ corresponding to the hook-shaped guide portion 63a is made smaller than the outer diameter Db of the valve holder 90, and the hook-shaped guide portion 63a If the gap β formed between the valve holder 90 and the guide stem 80 is made smaller than the gap α ′ formed between the guide stem 80 and the guide stem 80, the guide stem 80 and the valve holder 90 are likely to interfere with each other. However, by making it like this embodiment (FIG. 5 (A)), interference with the guide stem 80 and the valve holder 90 is prevented, the assembly | attachment precision of the valve holder 90 to the valve shaft 60, and those coaxiality Even if it is low, it is possible to prevent adverse effects on the operating performance and durability.

  By the way, in the above embodiment, the connection holding portion 82 is integrally provided at the lower end portion of the cylindrical portion 81 of the guide stem 80, and the upper hook-like portion 82 a of the connection holding portion 82 is formed on the valve chamber forming member 74 of the valve body 70. It is placed on the can receiving collar 74a and welded.

  When welding the upper hook-like portion 82a of the connection holding portion 82 and the can-receiving hook-like portion 74a of the valve chamber forming member 74, the first conduit 41 is provided on one side of the valve chamber forming member 74, A jig 110 as shown in FIG. 6 is used because the second conduits 42 are connected and fixed to the lower part thereof.

  The upper surface 110a of the illustrated jig 110 is a flat receiving surface, and the valve chamber forming member 74 (the body) is dropped into the upper surface 110a from the upper side and is inserted and held. A holding hole 111 is formed, and the can receiving collar 74a is placed on a portion of the upper surface portion 110a around the insertion holding hole 111. Further, on the side portion of the jig 110, when the can receiving trough-shaped portion 74a is placed on a portion around the fitting insertion holding hole 111 in the upper surface portion 110a, a first conduit protruding laterally is provided. In order to allow the 41 portion to pass from the top to the bottom, a notch opening 112 having a U-shaped upper surface opening is formed.

  When the upper hook-shaped portion 82a of the connection holding portion 82 and the can-receiving hook-shaped portion 74a of the valve chamber forming member 74 are welded and joined using such a jig 110, it is shown in FIGS. As shown, the valve chamber forming member 74 (the body part) is dropped into the insertion holding hole 111 from above, and the can receiving collar 74a is placed on the portion around the insertion insertion holding hole 111 in the upper surface part 110a. Thereafter, the cylindrical portion 82b of the connection holding portion 82 is fitted (press-fitted) into the inner periphery of the valve chamber forming member 74, and the upper hook-like portion 82a of the connection holding portion 82 is placed on the can receiving hook-like portion 74a. Then, welding is performed under pressure (see also FIG. 2).

  Here, as described above, on the lower surface side of the upper hook-like portion 82a of the connection holding portion 82, as can be understood by referring to FIG. 7 in addition to FIG. The protrusion 82e bites into the can receiving collar 74a when the upper collar 82a is put on the can receiving collar 74a and pressed (see FIG. 7D). The joint strength of welding (projection welding) is improved.

  However, when the annular protrusion 82a as described above is provided, the following problem may occur. That is, since the notch opening 112 for allowing the first conduit 41 to pass through is formed in the jig 110 as described above, the can receiving trough-shaped portion 74a is inserted into the fitting insertion holding hole 111 in the upper surface portion 110a. Even if it is placed on the surrounding part, a part of the can receiving collar 74a (the part located on the notch opening 112) is not received by the upper surface part 110a. Therefore, even if the upper hook-shaped portion 82a is put on the can-receiving hook-shaped portion 74a and pressed, a uniform force cannot be applied to the entire circumference of the can-receiving hook-shaped portion 74a and the upper hook-shaped portion 82a. Of the protrusion 82e, the portion of the protrusion 82e located on the notch opening 112 has a smaller amount of bite into the can-receiving hook-shaped portion 74a than the other portions. The guide stem 80 is tilted, the required coaxiality is not obtained, and this is a factor that deteriorates the performance of the product.

  On the other hand, instead of the annular projection 82e, as shown in FIG. 8, convex projections having a circular cross section, for example, are provided at several locations on the lower surface of the upper flange portion 82a (here, three locations at intervals of 120 °). In the case where 82e ′ is provided, if the convex protrusion 82e ′ is received by the upper surface portion 110a via the can receiving collar 74a, it is possible to apply a force uniformly to each protrusion 82e ′. However, since the guide stem 80 must be positioned with respect to the valve chamber forming member 74 so that the projections 82e ′ are not located on the notch opening 112, it is troublesome and troublesome. is there.

  On the other hand, as shown in FIG. 9, on the upper surface of the can receiving rod-shaped portion 74a, there are some portions (in this case, three at intervals of 120 °) that are out of the first conduit 41 in plan view. In addition, for example, when the convex protrusion 74e having a circular cross section is provided, the convex protrusion 74e portion is always received by the upper surface portion 110a portion other than the notch opening 112, and therefore, a uniform force is applied to each protrusion 74e. You can hang it. As a result, the amount of biting of each protrusion 74e into the upper bowl-shaped portion 82a becomes equal, and the problem that the guide stem 80 tilts with respect to the valve chamber forming member 74 does not occur, and the required coaxiality can be obtained. Thus, the performance of the product can be improved.

DESCRIPTION OF SYMBOLS 10 Motorized valve 16 Screw feed mechanism 30 Rotor 28 Fixed screw part 29 Movable screw part 40 Can 41, 42 Conduit 50 Stator 60 Valve shaft 63a Gutter-shaped guide part 61 Valve body 68 Fixed stopper 69 Movable stopper 70 Valve main body 71 Valve chamber 72 Valve Seat member 72a Valve port 74 Valve chamber forming member 74a Can receiving hook-shaped portion 74e Projection 80 Guide stem 82 Connection holding portion 82a Upper hook-shaped portions 82e, 82e 'Projection 90 Valve holder

Claims (2)

  A valve stem, a guide stem having a cylindrical portion into which the valve shaft is inserted, a cylindrical valve holder which is held and fixed to a lower end portion of the valve shaft and is inserted into the guide stem, and the valve holder, A valve body that is inserted in a state in which relative movement and relative rotation in the axial direction with respect to the valve shaft are possible, and that is prevented from coming off; a valve body that has a valve seat that contacts and separates the valve body; and the valve A can that is joined to the main body, a rotor that is disposed on the inner periphery of the can, a stator that is disposed on the outer periphery of the can for rotationally driving the rotor, and an internal thread member attached to the guide stem. A screw feed mechanism for bringing the valve body into and out of contact with the valve seat, comprising a fixed screw portion formed on the periphery and a movable screw portion formed on the outer periphery of the valve shaft; An eaves-shaped guide portion having an outer diameter smaller than the inner diameter of the cylindrical portion of the guide stem With kicked, electric valve, characterized in that towards the outer diameter of the valve holder than the outer diameter of the collar-like guide portion is small.   The motor operated valve according to claim 1, wherein an upper end portion of the valve holder is caulked and fixed to a lower end portion of the valve shaft.

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