JP2019163863A - Electric valve - Google Patents

Abstract

To provide an electric valve capable of restricting, by means of simple configuration, dimensional variation in a clearance formed between a valve body and valve seat part at an origin position.SOLUTION: Between a rotor press 72 and a push nut 71, a positioning part 73 is interposed which has a thickness corresponding to a dimension in a lift direction of a clearance formed between a valve body 14 and valve seat part 46a when the valve body 14 is located at a lowest position. The rotor press 72 and the positioning part 73 are formed integrally or separately.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric valve that is used as a flow control valve or the like in a refrigeration cycle such as an air conditioner or a refrigerator, and in particular, a valve body is in a lowest lowered position (normally in a fully closed state). In some cases, the present invention relates to a valveless type electric valve in which a gap of a predetermined size is formed between the valve seat portion and the valve seat portion.

  As this type of electric valve, for example, a valve stem, a guide stem having a cylindrical portion into which the valve shaft is inserted, and a cylindrical shape inserted into the guide stem that is held and fixed to the lower end portion of the valve shaft. A valve holder and a coil spring that is inserted in the valve holder in an axially movable and relatively rotatable state with respect to the valve shaft, and is attached downward by a coil spring that is retracted between the valve shaft and the valve shaft. And a valve body that is prevented from coming off and locked by the valve holder, a valve seat part to which the valve body comes into contact with and separated from, and a valve body to which the guide stem is attached and fixed, and a joint to the valve body A can, a rotor disposed on the inner periphery of the can, a rotor holder that connects the rotor and the valve shaft via a coupling member that is externally fitted to the upper end of the valve shaft, and the rotor Formed on the rotor holder so that the engaging part provided in A recessed portion, a stator disposed on the outer periphery of the can to rotationally drive the rotor, a female screw member disposed on the inner periphery of the cylindrical portion of the guide stem, and a fixing formed on the inner periphery of the female screw member A screw feed mechanism for bringing the valve body into and out of contact with the valve seat portion, which is composed of a screw portion and a movable screw portion formed on the outer periphery of the valve shaft, and is arranged on the outer periphery of the cylindrical portion of the guide stem. A stopper mechanism for restricting the rotational up and down movement of the rotor, and the stopper mechanism is in contact with a spiral fixed stopper having an upper locking portion and a lower locking portion, and the upper locking portion. A first contact portion that is locked in this manner and a second contact portion that is contacted and locked to the lower side lock portion, and are incorporated in the spiral portion of the fixed stopper. The slider is formed of the slider. When the rotor rotates, the first contact portion is pushed by the pushing portion provided on the rotor, and the first contact portion becomes the upper locking portion, and the second contact portion. In the origin position where the second contact portion of the slider is brought into contact with the lower locking portion and stopped until it comes into contact with the lower locking portion. It is known that a gap having a predetermined size is formed between the valve body and the valve seat portion (see, for example, Patent Document 1).

  In the air conditioner using the motor-operated valve having the configuration as described above, even when the valve body is in the lowest lowered position (normally in a fully closed state), there is a gap of a predetermined size between the valve seat portion. Therefore, for example, when dehumidifying operation is performed at midnight, it can be operated with the amount of refrigerant reduced without fully closing the motorized valve, and the generation of operating noise due to the on / off of the motorized valve can be suppressed. Can do.

Japanese Patent No. 5164579

  By the way, in the conventional valve-less type motorized valve as described above, the rotor connected and fixed to the valve shaft is finally rotated in the valve-closing direction until the slider is set at the origin position, and the valve body and The gap of the predetermined size is formed between the valve seat portion. Therefore, the dimensional accuracy of the gap between the valve body and the valve seat portion at the origin position depends on the component accuracy of components having complicated shapes such as the valve body and the valve body (valve seat portion thereof). There is a possibility that the dimensional variation of the gap becomes large.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to reduce the dimensional variation of the gap formed between the valve body and the valve seat portion at the origin position with a simple configuration. The object is to provide an electric valve that can be suppressed.

  In order to solve the above-described problems, a motor-operated valve according to the present invention is inserted in a state in which a valve shaft having a valve body at a lower end portion and the valve shaft is relatively movable and relatively rotatable in the axial direction. A guide bushing having a cylindrical part; a valve body having a valve seat part to which the valve body contacts and separates; and a guide body to which the guide bushing is attached and fixed; a can joined to the valve body; an inner side of the can and the guide A rotor disposed outside the bush, a stator disposed outside the can for rotationally driving the rotor, a cylindrical portion into which the guide bush is inserted, and an insertion through which the upper end portion of the valve shaft is inserted A valve shaft holder that rotates integrally with the rotor while supporting the rotor in the can, and the valve shaft and the valve shaft holder are separated in the up-down direction. With direction The biasing member interposed between the valve shaft and the valve shaft holder, the valve shaft holder and the rotor to prevent relative movement in the ascending / descending direction, and the valve shaft and the valve shaft holder, A locking member comprising a fixing member that is externally fitted and fixed to the upper end portion of the valve shaft, and a rotor presser that is a flat plate member interposed between the fixing member and the rotor. The valve shaft connected to the valve shaft holder according to the rotational drive of the rotor, comprising a stop member, a fixed screw portion formed on the guide bush, and a movable screw portion formed on the valve shaft holder. A screw feed mechanism for raising and lowering the valve body with respect to the valve seat part, and a lower stopper mechanism for restricting the downward movement of the valve shaft holder, when the valve shaft holder is in the lowest lowered position. And the valve body and the valve A motor-operated valve having a gap between the rotor portion and the fixing member, and a positioning portion having a thickness corresponding to a dimension of the gap in the ascending / descending direction. It is characterized by that.

  In a preferred embodiment, the rotor retainer and the positioning portion are integrally formed, and the upper end portion of the valve shaft is slidable in the rotor retainer with the positioning portion so as to cross a step formed by the positioning portion. A long hole that is inserted through is formed.

  In another preferred embodiment, the rotor retainer and the positioning portion are formed separately, and a notch into which the upper end portion of the valve shaft is slidably fitted is formed in the positioning portion.

  According to the motor-operated valve of the present invention, the gap in the ascending / descending direction of the gap formed between the valve body and the valve seat portion when the valve body is at the lowest lowered position between the rotor presser and the fixing member is equivalent. By interposing the positioning portion having the thickness to be determined, a gap between the valve body and the valve seat portion when the valve body is at the lowest lowered position, in other words, when the valve body is at the lowest lowered position is defined. That is, since the dimensional accuracy of the gap between the valve body and the valve seat portion at the origin position depends on the component accuracy of the positioning portion formed with a constant thickness, for example, a complicated structure such as a valve body or a valve body. Compared with the case where the dimensional accuracy of the gap is determined by the component accuracy of the component having a shape, the dimensional variation of the gap can be suppressed, and the controllability of the fluid (refrigerant) flow rate in the low flow rate region is improved. Can be made.

  In addition, the rotor retainer and the positioning portion are integrally formed, and the rotor retainer with the positioning portion has a long hole through which the upper end portion of the valve shaft is slidably inserted so as to cross the step formed by the positioning portion. By forming, an increase in the number of parts can be prevented.

  In addition, the rotor retainer and the positioning portion are formed separately, and a notch into which the upper end portion of the valve shaft is slidably inserted is formed in the positioning portion, thereby improving the component accuracy of the positioning portion. Since the height is further increased, the dimensional variation of the gap can be more effectively suppressed.

The longitudinal cross-sectional view which shows 1st Embodiment of the motor operated valve which concerns on this invention. It is a figure which shows the rotor of the motor operated valve shown by FIG. 1, (A) is a top view, (B) is AA arrow sectional drawing of (A). It is a figure which shows the valve stem holder of the motor operated valve shown by FIG. 1, (A) is a perspective view, (B) is a front view, (C) is a left view, (D) is a right view, (E) Is a top view, (F) is a bottom view, and (G) is a cross-sectional view taken along line BB in (D). FIG. 2 is a diagram for explaining a process of assembling a rotor and a valve shaft holder in the motor-driven valve assembly process shown in FIG. 1, and (A) is just before the valve shaft holder is inserted into the inner cylinder of the rotor. The longitudinal cross-sectional view which shows the state of this, and CC sectional drawing of the longitudinal cross-sectional view, (B) is the longitudinal cross-sectional view which shows the state in which the taper surface part of the valve-shaft holder was inserted in the inner cylinder of a rotor, and its longitudinal cross-section CC sectional drawing of a surface view, (C) is a longitudinal cross-sectional view which shows the state by which the flat surface part of the valve-shaft holder was inserted in the inner cylinder of a rotor, and CC arrow sectional drawing of the longitudinal cross-sectional view (D) is the longitudinal cross-sectional view which shows the state by which the protrusion of the valve-shaft holder was inserted in the inner cylinder of a rotor, and CC sectional view taken on the line of the longitudinal cross-sectional view. It is a figure which shows the rotor holding | suppressing part with the positioning part of the motor operated valve shown by FIG. 1, (A) is a top view, (B) is DD sectional view taken on the line of (A). In the assembly process of the motor-operated valve shown in FIG. 1, it is a figure used for description of the origin position (the lowest lowered position) of the valve body, (A) is a top view and a longitudinal sectional view showing a seating state, B is a top view and a longitudinal sectional view showing a separated state. The figure which shows the flow volume characteristic of the motor operated valve shown by FIG. The longitudinal cross-sectional view which shows 2nd Embodiment of the motor operated valve which concerns on this invention. It is a figure which shows the positioning part of the motor operated valve shown by FIG. 8, (A) is a top view, (B) is EE arrow sectional drawing of (A). FIG. 9 is a diagram used for explaining the origin position (lowermost position) of the valve body in the assembly process of the electric valve shown in FIG. 8, and (A) is a top view and a longitudinal sectional view showing a seating state; B is a top view and a longitudinal sectional view showing a separated state.

  Hereinafter, embodiments of a motor-operated valve according to the present invention will be described with reference to the drawings. In each drawing, gaps formed between members, separation distances between members, etc. may be exaggerated for easy understanding of the invention and for convenience of drawing. is there. Further, in this specification, descriptions representing positions and directions such as up and down and left and right are based on the direction arrow indications of FIGS. 1 and 8 and do not indicate the positions and directions in the actual use state.

[First Embodiment]
FIG. 1 is a longitudinal sectional view showing a first embodiment of a motor-operated valve according to the present invention.

  The motor-driven valve 1 of the illustrated embodiment mainly includes a stepping motor 50 including a valve shaft 10, a guide bush 20, a valve shaft holder 30, a valve body 40, a can 55, a rotor 51 and a stator 52, A compression coil spring (biasing member) 60, a retaining stopper 70, a screw feed mechanism 28, and a lower stopper mechanism 29 are provided.

  The valve shaft 10 has an upper small-diameter portion 11, an intermediate large-diameter portion 12, and a lower small-diameter portion 13 from above, and a stepped inverted conical valve body 14 at the lower end portion of the lower small-diameter portion 13. Are integrally formed.

  The guide bush 20 includes a cylindrical portion 21 that is inserted in a state in which the valve shaft 10 (the intermediate large-diameter portion 12) is relatively movable (slidable) in the direction of the axis O and is relatively rotatable about the axis O, and The cylinder portion 21 extends upward from the upper end portion, has an inner diameter larger than that of the cylinder portion 21, and is inserted into the upper end side of the intermediate large diameter portion 12 and the lower end side of the upper small diameter portion 11 of the valve shaft 10. And an installation part 22. On the outer periphery of the cylindrical portion 21 of the guide bush 20, one of the screw feeding mechanisms 28 that raises and lowers the valve body 14 of the valve shaft 10 with respect to the valve seat portion 46 a of the valve main body 40 according to the rotational drive of the rotor 51. A fixed screw portion (male screw portion) 23 is formed, and a fixed stopper body 24 that constitutes one of the lower stopper mechanisms 29 for restricting the downward movement of the valve shaft holder 30 is formed at the lower end of the fixed screw portion 23. Is screwed.

  The valve shaft holder 30 includes a cylindrical portion 31 into which the guide bush 20 is inserted and a ceiling portion 32 through which an insertion hole 32a through which the upper end portion of the valve shaft 10 (the upper small diameter portion 11 thereof) is inserted. Have. On the inner periphery of the cylindrical portion 31 of the valve shaft holder 30, a movable screw portion (female screw portion) 33 that is screwed with the fixed screw portion 23 of the guide bush 20 and constitutes the screw feeding mechanism 28 is formed. A movable stopper body 34 constituting the other of the lower stopper mechanism 29 is integrally projected at the lower end of the outer periphery of the cylindrical portion 31.

  Further, between the terrace surface formed between the upper small diameter portion 11 and the intermediate large diameter portion 12 of the valve shaft 10 and the lower surface of the ceiling portion 32 of the valve shaft holder 30, the upper small diameter of the valve shaft 10 is provided. The valve shaft 10 and the valve shaft holder 30 are energized in a direction away from each other in the ascending / descending direction (axis O direction) so as to be extrapolated to the portion 11, in other words, the valve shaft 10 is always downward (valve closing direction). A compression coil spring (biasing member) 60 that urges the coil spring is deflated.

  The said valve main body 40 is comprised from metal cylinders, such as brass and SUS, for example. The valve body 40 has a valve chamber 40a inside, and a first conduit 41a is connected and fixed to a lateral first opening 41 provided on a side portion of the valve chamber 40a by brazing or the like. The guide bush 20 and the insertion hole 43 through which the valve shaft 10 (the intermediate large-diameter portion 12) is inserted in a state in which the valve shaft 10 (the intermediate large-diameter portion 12) is relatively movable (slidable) in the direction of the axis O and relatively rotatable about the axis O. A fitting hole 44 to which the lower end portion of (cylindrical portion 21) is fitted and fixed is formed, and the second conduit 42a is inserted into the vertical second opening 42 provided in the lower portion of the valve chamber 40a. A valve orifice 46 having a valve seat portion 46a with which the valve body 14 contacts and separates is formed on the bottom wall 45 between the valve chamber 40a and the second opening 42. .

  A flange plate 47 is fixed to the upper end portion of the valve body 40 by caulking or the like, and a lower end portion of a cylindrical can 55 with a ceiling is butt welded to a step portion provided on the outer periphery of the flange plate 47. Has been.

  A rotor 51 is rotatably disposed inside the can 55 and outside the guide bush 20 and the valve shaft holder 30. A yoke 52a, A stator 52 including a bobbin 52b, a stator coil 52c, a resin mold cover 52d, and the like is disposed. A plurality of lead terminals 52e are connected to the stator coil 52c, and a plurality of lead wires 52g are connected to these lead terminals 52e via a substrate 52f, and are arranged in the can 55 by energization excitation to the stator coil 52c. The existing rotor 51 rotates about the axis O.

  The rotor 51 disposed in the can 55 is engaged and supported by the valve shaft holder 30, and the valve shaft holder 30 rotates together with the rotor 51 (integrally).

  Specifically, the rotor 51 is a double pipe comprising an inner cylinder 51a, an outer cylinder 51b, and a connecting portion 51c that connects the inner cylinder 51a and the outer cylinder 51b, as can be understood with reference to FIG. The height of the inner cylinder 51a in the vertical direction is smaller than the height of the outer cylinder 51b in the vertical direction, and the inner cylinder 51a is accommodated inside the outer cylinder 51b. Further, a receiving surface (D cut surface) 51d formed of a plane (at an angular interval of 120 degrees around the axis O) is formed on the inner periphery of the inner cylinder 51a, and the center of the receiving surface 51d is formed along the vertical direction. A vertical groove 51e is provided. The connecting portion 51c is provided at the same position as the receiving surface 51d and the vertical groove 51e (at an angular interval of 120 degrees around the axis O).

  On the other hand, the outer periphery of the valve shaft holder 30 is provided with a tapered surface 30a formed of a truncated cone surface at the upper end thereof, as can be understood with reference to FIG. 3 (at an angular interval of 120 degrees around the axis O). ) A flat surface (D-cut surface formed by cutting a part of the outer periphery of the valve shaft holder 30) 30b is provided continuously from the tapered surface 30a, and more than the upper end edge of the flat surface 30b. A ridge 30c extending in the vertical direction downward from the lower position is projected, and a quadrangular frustum-shaped taper portion 30d that becomes thinner as it goes upward is provided at the upper end of the ridge 30c. . Here, the flat surface 30 b of the valve shaft holder 30 has a shape complementary to the receiving surface 51 d of the rotor 51, and the protrusion 30 c of the valve shaft holder 30 is fitted into the vertical groove 51 e of the rotor 51. It has a shape. Further, the flat surface 30b (and the protrusion 30c formed in the center of the flat surface 30b along the vertical direction) extends to the middle part of the valve shaft holder 30, and at the lower end of the flat surface 30b. A locking surface 30e for supporting the rotor 51 is formed on both sides of the lower portion of the protrusion 30c.

  The step of assembling the rotor 51 and the valve shaft holder 30 will be described in detail with reference to FIG. 4. The valve shaft holder 30 is attached to the inner cylinder 51a of the rotor 51 through the lower opening of the outer cylinder 51b of the rotor 51. When approaching (see FIG. 4A), first, a portion (tapered surface portion) including the tapered surface 30a provided at the upper end of the valve shaft holder 30 is inserted into the inner cylinder 51a (FIG. 4B). Next, a portion (flat surface portion) including the flat surface 30b continuously provided on the tapered surface 30a is inserted into the inner cylinder 51a (see FIG. 4C), and the flat surface 30b of the valve shaft holder 30 is The receiving surface 51d of the rotor 51 is engaged, so that the center axis of the valve shaft holder 30 and the rotor 51 and the angular position around the center axis are approximately aligned. When the valve shaft holder 30 is further inserted into the inner cylinder 51a, the protrusion 30c protruding from the flat surface 30b is inserted into the inner cylinder 51a from the tapered portion 30d provided at the upper end thereof (FIG. 4). (See (D)), the protrusion 30c of the valve shaft holder 30 and the vertical groove 51e of the rotor 51 are engaged, and the center axis of the valve shaft holder 30 and the rotor 51 and the angular position around the center axis are precise. To be aligned. When the valve shaft holder 30 is further inserted into the inner cylinder 51a, the locking surface 30e of the valve shaft holder 30 and the lower surface of the rotor 51 come into contact with each other, and the rotor 51 is supported and fixed by the valve shaft holder 30. .

  Thus, the locking surface 30e of the valve shaft holder 30 and the lower surface of the rotor 51 abut, the flat surface 30b of the valve shaft holder 30, the receiving surface 51d of the rotor 51, the protrusion 30c of the valve shaft holder 30, and the rotor 51. When the vertical groove 51 e is engaged, the valve shaft holder 30 is rotated together with the rotor 51 while supporting the rotor 51 in the can 55.

  As shown in FIG. 1, relative movement of the valve shaft holder 30 and the rotor 51 in the ascending / descending direction is prevented on the upper side of the rotor 51 and the valve shaft holder 30 (in other words, the rotor 51 with respect to the valve shaft holder 30). Push nut (fixing member) that is externally fitted and fixed to the upper end portion of the valve shaft 10 (the upper small-diameter portion 11 thereof) by press-fitting, welding, or the like to connect the valve shaft 10 and the valve shaft holder 30 together. ) 71 and a rotor retaining member 70 composed of a flat plate-like member interposed between the push nut 71 and the rotor 51 are disposed. That is, the rotor 51 is sandwiched between the valve shaft holder 30 biased upward by the biasing force of the compression coil spring 60 and the rotor presser 72. The height (vertical direction) from the upper end of the valve shaft holder 30 to the locking surface 30e is the same as the height (vertical direction) of the inner cylinder 51a of the rotor 51, and the ceiling of the valve shaft holder 30 32) is in contact with the lower surface (flat surface) of the rotor retainer 72.

  Further, in the present embodiment, a positioning portion 73 having a predetermined thickness H is integrally formed on the rotor presser 72 (the upper left half portion thereof), as can be understood with reference to FIG. An elongated hole 74 through which the upper end portion of the valve shaft 10 is slidably inserted in the lateral direction so as to cross the step formed by the positioning portion 73 (a step having a height H) is formed in the rotor retainer 72 with the positioning portion 73. Is formed. As shown in FIG. 1, the rotor retainer 72 with the positioning portion 73 has a positioning portion 73 interposed between the rotor retainer 72 and the push nut 71, in other words, the push nut 71 is mounted on the positioning portion 73. Thus, when the valve body 14 is at the lowest lowered position (origin position), the valve body 14 and the valve seat portion 46a are spaced by the thickness H of the positioning portion 73. A gap is formed.

  The origin position (lowermost position) of the valve body 14 by the rotor presser 72 with the positioning portion 73 will be described in detail with reference to FIG. 6. First, the valve shaft 10, the guide bush 20, the compression coil spring 60, the valve shaft. With the holder 30, the rotor 51, the fixed stopper body 24, the valve main body 40, and the like assembled, the screw feeding mechanism 28 including the fixed screw portion 23 of the guide bush 20 and the movable screw portion 33 of the valve shaft holder 30 is used. The valve shaft holder 30, the rotor 51, and the valve shaft 10 are lowered while rotating. The valve body 14 provided at the lower end portion of the valve shaft 10 contacts (sits) the valve seat portion 46a, the compression coil spring 60 is slightly compressed, and the movable stopper body 34 and the guide of the valve shaft holder 30 are also compressed. In a state where the fixed stopper body 24 fixed to the bush 20 comes into contact with the valve shaft holder 30 at the lowest position, the rotor presser 72 is fitted to the upper end portion of the valve shaft 10 and the push nut 71 is installed. Fix by external fitting by press-fitting or welding. At this time, the push nut 71 is fixed in a state where it is placed on a portion other than the positioning portion 73 of the rotor presser 72 (sitting state, see FIG. 6A).

  Next, with the valve shaft holder 30 in the lowest position, the valve shaft 10 is lifted against the urging force of the compression coil spring 60 and positioned with the upper end of the valve shaft 10 inserted through the elongated hole 74. When the rotor presser 72 with the portion 73 is slid in the lateral direction (rightward in the figure), the positioning portion 73 is interposed between the rotor presser 72 and the push nut 71, and the lifting force on the valve shaft 10 is released, the push The nut 71 is disposed on the positioning portion 73 of the rotor retainer 72, and the valve shaft 10 is lifted with respect to the valve main body 40 by the thickness H of the positioning portion 73, whereby the valve body 14 and the valve seat portion. A gap corresponding to the thickness H of the positioning portion 73 (a gap having a dimension H in the ascending / descending direction) is formed between 46a and 46a (separated state, see FIG. 6B).

  Finally, the push nut 71 (the lower end portion thereof) and the positioning portion 73 of the rotor presser 72 may be fixed by welding or the like.

  Thereby, when the valve body 14 is at the lowest lowered position (origin position), a gap is formed between the valve body 14 and the valve seat portion 46a so that the dimension in the elevation direction corresponds to the thickness H of the positioning portion 73. Will be.

  Also, the push nut 71 fixed to the upper end portion of the valve shaft 10 moves the valve shaft holder 30 excessively upward relative to the guide bush 20 during operation, and the fixing screw portion 23 of the guide bush 20 and the valve In order to prevent the threaded engagement with the movable screw portion 33 of the shaft holder 30, a return spring 75 made of a coil spring that biases the valve shaft holder 30 toward the guide bush 20 is provided.

  In the motor-operated valve 1 having such a configuration, when the rotor 51 is rotated by energizing and exciting the stator 52 (the stator coil 52c), the valve shaft holder 30 and the valve shaft 10 are rotated integrally therewith. At this time, the valve shaft 10 is moved up and down with the valve body 14 by the screw feeding mechanism 28 composed of the fixed screw portion 23 of the guide bush 20 and the movable screw portion 33 of the valve shaft holder 30, thereby the valve body 14. And the valve seat part 46a are increased or decreased to adjust the flow rate of the fluid such as the refrigerant. Further, even when the movable stopper body 34 of the valve shaft holder 30 and the fixed stopper body 24 fixed to the guide bush 20 are in contact with each other and the valve body 14 is in the lowest lowered position, the valve body 14 and the valve seat portion 46a Since a gap (required lift amount when the valve is closed) is formed between them, a predetermined amount of passage flow rate is secured (see FIG. 7).

  Thus, in the motor-operated valve 1 of the first embodiment, between the rotor presser 72 and the push nut 71, between the valve body 14 and the valve seat portion 46a when the valve body 14 is in the lowest lowered position. A positioning portion 73 having a thickness corresponding to the dimension of the gap formed in the ascending / descending direction is interposed, and when the valve shaft holder 30 is in the lowest lowered position by the lower stopper mechanism 29, the push nut 71 is pressed against the rotor. 72, when the valve body 14 is in contact with the valve seat portion 46a, the valve shaft 10 is lifted against the urging force of the compression coil spring 60, and the rotor presser 72 and the push nut 71 When the positioning portion 73 is interposed between the valve body 10 and the valve body 40, the valve shaft 10 is lifted by the thickness of the positioning portion 73, and the gap is formed between the valve body 14 and the valve seat portion 46a. form Each part is designed so that the separated state can be taken, and when the positioning part 73 is interposed between the rotor presser 72 and the push nut 71, the lowermost position of the valve body 14, in other words, For example, a gap between the valve body 14 and the valve seat portion 46a when the valve body 14 is at the lowest lowered position is defined. That is, since the dimensional accuracy of the gap between the valve body 14 and the valve seat portion 46a at the origin position depends on the component accuracy of the positioning portion 73 formed with a constant thickness, the dimensional variation of the gap Therefore, the controllability of the fluid (refrigerant) flow rate in the low flow rate region can be improved.

  Further, since the rotor presser 72 and the positioning portion 73 are integrally formed, an increase in the number of parts can be prevented.

[Second Embodiment]
FIG. 8 is a longitudinal sectional view showing a second embodiment of the electric valve according to the present invention.

  The only difference between the motor-operated valve 1A of the second embodiment and the motor-operated valve 1 of the first embodiment is the configuration of the rotor presser and the positioning portion. Therefore, only the configuration of the rotor retainer and the positioning portion will be described in detail, and the same configuration as the motor-operated valve 1 shown in FIG. The operation of the motor-operated valve 1A of the present embodiment is the same as that of the motor-operated valve 1 in the first embodiment.

  In the motor-operated valve 1A of the illustrated embodiment, the rotor retainer 72A and the positioning portion 73A are formed separately, and the upper end of the valve shaft 10A (the upper small diameter portion 11A) is inserted into the rotor retainer 72A. A hole 74A is formed, and a notch (notch with one end opened) 76A into which the upper end portion of the valve shaft 10A (the upper small diameter portion 11A thereof) is slidably inserted in the lateral direction is formed in the positioning portion 73A. (See FIG. 9 in particular). That is, in the present embodiment, the positioning portion 73A is configured by a flat plate-like member having a substantially C shape in plan view, and as shown in FIG. 8, the positioning portion 73A is interposed between the rotor presser 72A and the push nut 71A. Positioning portion 73A is interposed, so that when valve body 14A is at the lowest lowered position (origin position), it is between valve body 14A and valve seat portion 46aA by the thickness HA of positioning portion 73A. A gap is formed.

  The origin position (lowermost position) of the valve body 14A by the positioning portion 73A will be described in detail with reference to FIG. 10. First, the valve shaft 10A, the guide bush 20A, the compression coil spring 60A, the valve shaft holder 30A, the rotor 51A, the fixed stopper body 24A, the valve main body 40A, etc. are assembled, and the valve shaft is utilized by using the screw feed mechanism 28A that becomes the fixed screw portion 23A of the guide bush 20A and the movable screw portion 33A of the valve shaft holder 30A. The holder 30A, the rotor 51A, and the valve shaft 10A are lowered while rotating. Then, the valve body 14A provided at the lower end of the valve shaft 10A contacts (seats) the valve seat portion 46aA, the compression coil spring 60A is slightly compressed, and the movable stopper body 34A of the valve shaft holder 30A and the guide In a state where the fixed stopper body 24A fixed to the bush 20A contacts and the valve shaft holder 30A is disposed at the lowest position, the rotor presser 72A is fitted into the upper end portion of the valve shaft 10A and the push nut 71A is fitted. Fix by external fitting by press-fitting or welding. At this time, the push nut 71A is fixed in a state where it is placed on the rotor presser 72A (sitting state, see FIG. 10A).

  Next, the valve shaft 10A is lifted against the urging force of the compression coil spring 60A while the valve shaft holder 30A is disposed at the lowest position, and the upper end of the valve shaft 10A is inserted into the notch 76A. When the portion 73A is slid in the lateral direction (leftward in the figure) while being interposed between the rotor retainer 72A and the push nut 71A and the lifting force with respect to the valve shaft 10A is released, the push nut 71A is placed on the positioning portion 73A. The valve shaft 10A is lifted by the thickness HA of the positioning portion 73A with respect to the valve main body 40A, whereby the thickness of the positioning portion 73A is between the valve body 14A and the valve seat portion 46aA. A gap corresponding to HA (a gap having a dimension HA in the ascending / descending direction) is formed (separated state, see FIG. 10B).

  Finally, the rotor presser 72A, the positioning portion 73A, the push nut 71A (the lower end portion thereof), and the positioning portion 73A may be fixed by welding or the like.

  Thereby, when the valve body 14A is at the lowest lowered position (origin position), a gap corresponding to the thickness HA of the positioning portion 73A is formed between the valve body 14A and the valve seat portion 46aA. Will be.

  Thus, in the motor operated valve 1A according to the second embodiment, the rotor retainer 72A and the positioning portion 73A are formed separately, and the positioning portion 73A is formed of a flat plate member, whereby the positioning portion 73A. Therefore, the dimensional variation of the gap can be more effectively suppressed.

DESCRIPTION OF SYMBOLS 1 Motorized valve 10 Valve stem 14 Valve body 20 Guide bush 21 Cylindrical part 23 Fixing screw part (male screw part)
24 fixed stopper body 28 screw feeding mechanism 29 lower stopper mechanism 30 valve shaft holder 30a taper surface 30b flat surface 30c protrusion 30d taper portion 30e locking surface 31 cylindrical portion 32 ceiling portion 33 movable screw portion (female screw portion)
34 movable stopper body 40 valve body 40a valve chamber 41 first opening 41a first conduit 42 second opening 42a second conduit 43 insertion hole 44 fitting hole 45 bottom wall 46 valve orifice 46a valve seat portion 47 bowl-shaped plate 50 stepping Motor 51 Rotor 51a Inner cylinder 51b Outer cylinder 51d Receiving surface 51e Vertical groove 52 Stator 55 Can 60 Compression coil spring (biasing member)
70 Retaining stop member 71 Push nut (fixing member)
72 Rotor retainer 73 Positioning part 74 Slot O O Axis

Claims (3)

A valve stem provided with a valve body at its lower end,
A guide bush having a cylindrical portion inserted in a state in which the valve shaft is relatively movable and relatively rotatable in the axial direction;
A valve body having a valve seat part to which the valve body comes into contact with and separated from and attached to the guide bush; and
A can joined to the valve body;
A rotor disposed inside the can and outside the guide bush;
A stator disposed outside the can to rotationally drive the rotor;
It has a cylindrical part into which the guide bush is inserted and a ceiling part through which an upper end of the valve shaft is inserted, and rotates integrally with the rotor while supporting the rotor in the can. A valve shaft holder,
An urging member interposed between the valve shaft and the valve shaft holder to urge the valve shaft and the valve shaft holder in a direction away from each other in the up-and-down direction;
A fixing member that is externally fitted and fixed to the upper end of the valve shaft to prevent relative movement of the valve shaft holder and the rotor in the up-and-down direction and to connect the valve shaft and the valve shaft holder; A retaining locking member constituted by a rotor presser composed of a flat plate member interposed between a fixing member and the rotor,
The valve body of the valve shaft, which comprises a fixed screw portion formed on the guide bush and a movable screw portion formed on the valve shaft holder, and is connected to the valve shaft holder in accordance with the rotational drive of the rotor. A screw feed mechanism for raising and lowering the valve seat part;
A lower stopper mechanism for restricting the rotational movement of the valve shaft holder, and
When the valve shaft holder is in the lowest lowered position, a motor-operated valve in which a gap is formed between the valve body and the valve seat portion,
A motor-operated valve comprising a positioning portion interposed between the rotor presser and the fixing member and having a thickness corresponding to a dimension of the gap in the ascending / descending direction.   The rotor retainer and the positioning portion are integrally formed, and the upper end portion of the valve shaft is slidably inserted into the rotor retainer with the positioning portion so as to cross the step formed by the positioning portion. The motor-operated valve according to claim 1, wherein an elongated hole is formed.   The rotor retainer and the positioning portion are formed separately, and the positioning portion is formed with a notch into which the upper end portion of the valve shaft is slidably inserted. The motor-operated valve according to 1.

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