JP6552835B2 - Motorized valve - Google Patents

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). The present invention also relates to a valve-less type motor-operated valve in which a gap of a predetermined size is formed between the valve seat and the valve seat.

  As a motorized valve of this type, for example, a guide stem having a valve stem, a cylindrical portion into which the valve stem is inserted, and a cylindrical stem held and fixed at the lower end of the valve stem and inserted in the guide stem The valve holder is inserted into the valve holder so as to be capable of axial relative movement and relative rotation with respect to the valve shaft, and is attached downward by a coil spring compressed 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 in order to engage , A stator disposed on the outer periphery of the can for rotationally driving the rotor, a female screw member disposed on the inner periphery of the cylindrical portion of the guide stem, and a stationary member formed on the inner periphery of the female screw member A screw feed mechanism for contacting and separating the valve body from the valve seat portion, which comprises a screw portion and a movable screw portion formed on the outer periphery of the valve shaft, and is disposed on the outer periphery of the cylindrical portion of the guide stem A stopper mechanism for restricting rotational movement of the rotor, the stopper mechanism being in contact with the spiral fixing stopper having an upper locking portion and a lower locking portion, and the upper locking portion Ring-shaped or spiral-shaped, provided with a first contact portion to be locked and a second contact portion to be locked in contact with the lower locking portion, and incorporated into the spiral portion of the fixed stopper The slider, and the slider When the rotor rotates, the first contact portion is pushed by the pressing portion provided on the rotor, and the first contact portion is in contact with 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 of 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, there is a gap of a predetermined size between the valve seat and the valve seat even when the valve body is at the lowest position (usually fully closed). 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.

Patent No. 5164579 gazette

  By the way, in the conventional valve-less type motor-operated 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 to the home position, A gap of the predetermined size is formed between the valve seat portion and the valve seat portion. Therefore, the dimensional accuracy of the gap between the valve body and the valve seat portion at the home position depends on the component accuracy of the component having a complicated shape such as the valve body and (the valve seat portion of) the valve body. There is a possibility that the dimensional variation of the gap becomes large.

  The present invention has been made in view of the above problems, and the object of the present invention is, with a simple configuration, the dimensional variation of the gap formed between the valve body and the valve seat portion at the origin position. It is providing the motor-operated valve which can be restrained.

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 inside 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. It comprises a stop member, a fixed screw portion formed on the outer periphery of the guide bush, and a movable screw portion formed on the inner periphery of the valve shaft holder, and is connected to the valve shaft holder according to the rotational drive of the rotor. A screw feed mechanism for raising and lowering the valve body of the valve shaft with respect to the valve seat portion, and a lower stopper mechanism for restricting the downward movement of the valve shaft holder. When in the lowered position A motor-operated valve in which a gap is formed between a body and the valve seat portion, and a positioning portion having a thickness corresponding to a dimension in the elevation direction of the gap is provided between the rotor presser and the fixing member. When the valve shaft holder is in the lowest lowered position by the lower stopper mechanism and the fixing member is disposed on the rotor presser, the valve body contacts the valve seat portion. When the seating state and the valve shaft is pulled up against the urging force of the urging member and the positioning portion is interposed between the rotor presser and the fixing member, the valve shaft becomes the valve body. The dimension and shape of each part are designed so that the gap is formed between the valve body and the valve seat part by being raised by the thickness of the positioning part. It is characterized by that.

  In a preferred embodiment, the rotor presser and the positioning unit are integrally formed, and the upper end of the valve stem is slidable across the step formed by the positioning unit on the rotor presser with the positioning unit. A long hole is formed to be inserted into the

  In another preferred embodiment, the rotor press and the positioning portion are separately formed, and the positioning portion is formed with a notch into which the upper end portion of the valve stem is slidably inserted.

  According to the motor-operated valve of the present invention, the dimension of the gap formed between the valve body and the valve seat portion when the valve body is at the lowest position is equivalent to the dimension in the elevating direction between the rotor presser and the fixing member. By positioning the positioning portion having the appropriate thickness, the gap between the valve body and the valve seat portion when the valve body is at the lowest position, in other words, when the valve body is at the lowest 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, the valve body and the valve body are complicated. As compared with the case where the dimensional accuracy of the gap is determined by the component accuracy of the component having the shape, the dimensional variation of the gap can be suppressed, thereby improving the controllability of the fluid (refrigerant) flow rate in the low flow rate region Can be made.

  Further, the rotor presser and the positioning unit are integrally formed, and the rotor presser with the positioning unit has an elongated hole through which the upper end portion of the valve shaft is slidably inserted so as to cross the step formed by the positioning unit. The formation can also prevent an increase in the number of parts.

  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 enhanced, dimensional variation of the gap can be suppressed more effectively.

BRIEF DESCRIPTION OF THE DRAWINGS 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 an upper side figure, (B) is an AA arrow sectional view 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, (G) is a B-B arrow sectional view of (D). FIG. 7 is a view provided to explain a process of assembling the rotor and the valve shaft holder in the assembly process of the motor-operated valve shown in FIG. 1, in which (A) is a state immediately before the valve shaft holder is inserted into the inner cylinder And a longitudinal sectional view taken along the line C-C of the longitudinal sectional view showing the state of the valve, (B) is a longitudinal sectional view showing the state where the tapered surface portion of the valve stem holder is inserted into the inner cylinder of the rotor C—C arrow sectional view of the plan view, (C) is a longitudinal sectional view showing a state in which the flat surface portion of the valve stem holder is inserted into the inner cylinder of the rotor and C—C arrow sectional view of the longitudinal 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). FIG. 7 is a view provided for explaining a process for bringing out the origin position (the most lowered position) of the valve body in the assembly process of the motor-operated valve shown in FIG. 1; (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 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 an EE arrow sectional view of (A). FIG. 9 is a view provided for explaining a process of bringing out the origin position (the most lowered position) of the valve body in the assembly process of the motor-operated valve shown in FIG. 8; (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 of the drawings, the gaps formed between the members, the separation distance between the members, etc. may be drawn in an exaggerated manner in order to facilitate 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-operated valve 1 of the illustrated embodiment mainly includes a valve shaft 10, a guide bush 20, a valve shaft holder 30, a valve body 40, a can 55, and a stepping motor 50 including a rotor 51 and a stator 52; A compression coil spring (biasing member) 60, a retaining member 70, a screw feed mechanism 28, and a lower stopper mechanism 29 are provided.

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

  The guide bush 20 is inserted in such a cylindrical portion 21 that (the intermediate large diameter portion 12 of the valve shaft 10 is capable of relative movement (sliding) in the direction of the axis O and relative rotation around the axis O; Extending upward from the upper end of the cylindrical portion 21, the inner diameter is larger than that of the cylindrical portion 21, and the upper end side of the middle large diameter portion 12 of the valve shaft 10 and the lower end side of the upper small diameter portion 11 are inserted. And an installation part 22. On the outer periphery of the cylindrical portion 21 of the guide bush 20, one of the screw feed mechanisms 28 for raising and lowering the valve body 14 of the valve shaft 10 with respect to the valve seat portion 46a of the valve main body 40 A fixed screw portion (male screw portion) 23 to be configured is formed, and at the lower end of the fixed screw portion 23, a fixed stopper body 24 which constitutes one of the lower stopper mechanisms 29 for restricting the rotational movement of the valve shaft holder 30. Is screwed.

  The valve shaft holder 30 has 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 upper small diameter portion 11 of) the valve shaft 10 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 urged away from each other in the raising and lowering direction (axial line 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 is biased to be biased.

  The valve body 40 is made of, for example, a metal cylinder such as brass or SUS. The valve main body 40 has a valve chamber 40a inside, and the first conduit 41a is connected and fixed to the first transverse opening 41 provided on the side of the valve chamber 40a by brazing or the like, and the valve chamber 40a (The intermediate large diameter portion 12 of the valve shaft 10 is relatively movable (slidable) in the direction of the axis O and is rotatable relative to the axis O in the ceiling portion of the valve hole 10 and the guide bush 20 A lower end portion of the (cylindrical portion 21) is fitted to form a fitting hole 44 to be fixedly attached, and the second conduit 42a is soldered to the vertically oriented second opening 42 provided at 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 wedge-shaped plate 47 is fixed to the upper end of the valve body 40 by caulking or the like, and the lower end of a cylindrical can 55 with a ceiling is butt-welded to a step provided on the outer periphery of the wedge-shaped 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, and a yoke 52a is provided outside the can 55 so as to rotationally drive the rotor 51. A stator 52 including a bobbin 52b, a stator coil 52c, and a resin mold cover 52d 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 the lead terminals 52e via the substrate 52f, and distributed in the can 55 by energization excitation to the stator coil 52c. The existing rotor 51 is designed to rotate around the axis O.

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

  In detail, the rotor 51 is a double pipe consisting of an inner cylinder 51a, an outer cylinder 51b, and a connecting portion 51c connecting the inner cylinder 51a and the outer cylinder 51b, as is well 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. Also, a receiving surface (D-cut surface) 51d consisting of a flat surface (at an angular interval of 120 degrees around the axis O) and an inner surface of the inner cylinder 51a are formed along the vertical direction at the center of the receiving surface 51d. 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, on the outer periphery of the valve shaft holder 30, as is well understood with reference to FIG. 3, a tapered surface 30a consisting of a truncated cone surface is provided at the upper end thereof (with an angular interval of 120 degrees around the axis O). A flat surface (a D-cut surface formed by cutting a part of the outer periphery of the valve shaft holder 30) 30b is connected in a row from the tapered surface 30a downward, and the upper surface of the flat surface 30b is smaller than the upper edge A protrusion 30c extending vertically in a downward direction from a lower position is provided so as to protrude downward, and a tapered portion 30d in the shape of a quadrangular frustum, which becomes thinner toward the top, is provided at the upper end of the protrusion 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 in the vertical groove 51 e of the rotor 51. It has a shape. Further, the flat surface 30b (and a protrusion 30c formed along the vertical direction at the center of the flat surface 30b) is extended to the middle portion of the valve stem holder 30, and the lower surface of the flat surface 30b is 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. As it gets closer (see FIG. 4A), first, a portion (a tapered surface portion) including a tapered surface 30a provided at the upper end of the valve shaft holder 30 is inserted into the inner cylinder 51a (FIG. 4B) Then, a portion (flat surface portion) including the flat surface 30b continuously provided to the tapered surface 30a is inserted into the inner cylinder 51a (see FIG. 4C), and the flat surface 30b of the valve stem holder 30 and 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 ridge 30c of the valve shaft holder 30 engages with the vertical groove 51e of the rotor 51 so that the central axis of the valve shaft holder 30 and the rotor 51 and the angular position around the central axis are precise To be aligned. Then, when the valve shaft holder 30 is further inserted into the inner cylinder 51a, the locking surface 30e of the valve shaft holder 30 abuts on the lower surface of the rotor 51, 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 abuts on the lower surface of the rotor 51, and the flat surface 30b of the valve shaft holder 30, the receiving surface 51d of the rotor 51, and the projections 30c of the valve shaft holder 30 and the rotor 51. The valve shaft holder 30 is rotated together with the rotor 51 while supporting the rotor 51 in the can 55 by the engagement of the vertical groove 51e.

  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). Of the valve shaft 10 and the valve shaft holder 30 together with a push nut (fixing member (fixed member) externally fitted and fixed to the upper end of (the upper small diameter portion 11 of) the valve shaft 10 A retaining locking member 70 is disposed, which is composed of a 71 and a rotor presser 72 made of a flat plate interposed between the push nut 71 and the rotor 51. 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 (in the vertical direction) from the upper end of the valve shaft holder 30 to the locking surface 30e is the same as the height (in the vertical direction) of the inner cylinder 51a of the rotor 51. The upper surface of 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 upper left half of the upper surface of) the rotor presser 72, as is well understood with reference to FIG. The rotor presser 72 with the positioning portion 73 has a long 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 (step of height H) formed by the positioning portion 73 Is formed. In the rotor presser 72 with the positioning unit 73, as shown in FIG. 1, the positioning unit 73 is interposed between the rotor presser 72 and the push nut 71. In other words, the push nut 71 is placed on the positioning unit 73. The valve body 14 is disposed between the valve body 14 and the valve seat portion 46 a by the thickness H of the positioning portion 73 when the valve body 14 is at the lowest position (home position). A gap is formed.

  Describing the origin position (highest position) of the valve 14 by the rotor holding member 72 having the positioning portion 73 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 being rotated. Then, the valve body 14 provided at the lower end portion of the valve shaft 10 contacts (seats) the valve seat portion 46a, the compression coil spring 60 is slightly compressed, and the movable stopper body 34 of the valve shaft holder 30 and the guide In a state where the fixed stopper body 24 fixed to the bush 20 abuts and the valve shaft holder 30 is disposed at the lowermost position, the rotor presser 72 is fitted to the upper end portion of the valve shaft 10 and the push nut 71 is Fix it by press fit, welding etc. 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).

  Then, with the valve shaft holder 30 disposed at the lowest position, the valve shaft 10 is pulled up against the biasing force of the compression coil spring 60, and positioning is performed with the upper end of the valve shaft 10 inserted in the long hole 74 The rotor retainer 72 with the part 73 is slid in the lateral direction (rightward in the figure), and the positioning part 73 is interposed between the rotor retainer 72 and the push nut 71 to release the pulling force on the valve shaft 10. The nut 71 is disposed on the positioning portion 73 of the rotor presser 72, and the valve shaft 10 is pulled up by the thickness H of the positioning portion 73 with respect to the valve main body 40, 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 lower end portion of) the push nut 71 and the positioning portion 73 of the rotor presser 72 may be fixed by welding or the like.

  Thus, when the valve body 14 is at the lowest position (home position), a gap corresponding to the thickness H of the positioning portion 73 is formed between the valve body 14 and the valve seat portion 46a. Will be.

  Further, in the push nut 71 fixed to the upper end portion of the valve shaft 10, the valve shaft holder 30 is moved upward too much with respect to the guide bush 20 at the time of 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 energization and energization of the stator 52 (the stator coil 52c thereof), 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. The clearance (lift amount) between the valve seat 46a and the valve seat 46a is 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 abuts against the fixed stopper body 24 fixed to the guide bush 20 and the valve body 14 is at the lowest position, the valve body 14 and the valve seat portion 46a Since a gap (valve closing required lift amount) is formed between them, a predetermined amount of passing flow rate is secured (see FIG. 7).

  As described above, in the motor operated valve 1 of the first embodiment, between the valve body 14 and the valve seat portion 46 a when the valve body 14 is at the lowest position, between the rotor presser 72 and the push nut 71. When the valve shaft holder 30 is at the lowermost position by the lower stopper mechanism 29, the push nut 71 presses the rotor When the valve body 14 is placed on the valve seat portion 46 a, the valve shaft 10 is pulled up against the biasing 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 achieved, and the positioning portion 73 is interposed between the rotor presser 72 and the push nut 71, so that the lowermost position of the valve body 14, in other words, For example, the gap between the valve body 14 and the valve seat portion 46a when the valve body 14 is at the lowest 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 Thus, the controllability of the fluid (refrigerant) flow rate in the low flow rate region can be improved.

  Further, by integrally forming the rotor presser 72 and the positioning portion 73, it is possible to prevent an increase in the number of parts.

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 this embodiment is the same as that of the motor-operated valve 1 of the first embodiment.

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

  Describing the origin position (highest descent position) step of the valve body 14A by the positioning portion 73A in detail with reference to FIG. 10, first, the valve shaft 10A, guide bush 20A, compression coil spring 60A, valve shaft holder 30A, rotor In a state where 51A, fixed stopper body 24A, valve main body 40A and the like are assembled, the valve shaft is utilized by using a screw feed mechanism 28A consisting of 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 being rotated. Then, the valve body 14A provided at the lower end of the valve stem 10A contacts (seats) the valve seat portion 46aA, the compression coil spring 60A is slightly compressed, and the movable stopper 34A of the valve stem 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 it by press fit, welding etc. 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 stem 10A is pulled up with respect to the valve main body 40A by the thickness HA of the positioning portion 73A, 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 of HA in the up-and-down 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.

  Thus, when the valve body 14A is at the lowest position (home 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.

  As described above, in the motor-operated valve 1A of the second embodiment, the rotor pressing portion 72A and the positioning portion 73A are separately formed, and the positioning portion 73A is formed of a flat plate-like member, thereby the positioning portion 73A. In the above, the dimensional accuracy 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 comprising a rotor presser comprising a flat plate-like member interposed between a fixing member and the rotor;
The valve shaft comprising a fixed screw portion formed on the outer periphery of the guide bush and a movable screw portion formed on the inner periphery of the valve shaft holder, and connected to the valve shaft holder according to the rotational drive of the rotor A screw feed mechanism for raising and lowering the valve body of the valve seat part,
A lower stopper mechanism for restricting the rotational movement of the valve shaft holder, and
A motor-operated valve in which a gap is formed between the valve body and the valve seat portion when the valve shaft holder is in the lowest position.
A positioning portion having a thickness corresponding to the dimension in the vertical direction of the gap is interposed between the rotor press and the fixing member.
When the valve shaft holder is in the lowest lowered position by the lower stopper mechanism, when the fixing member is disposed on the rotor presser, the seating state in which the valve body contacts the valve seat portion, and the valve When the shaft is pulled up against the urging force of the urging member and the positioning portion is interposed between the rotor presser and the fixing member, the valve shaft is positioned relative to the valve body. The size and shape of each part are designed so that the gap is formed between the valve body and the valve seat part. valve.   The rotor press and the positioning portion are integrally formed, and the upper end portion of the valve shaft is slidably inserted into the rotor press with the positioning portion so as to cross a step formed by the positioning portion. The motor operated valve according to claim 1, wherein an elongated hole is formed.   The rotor press and the positioning portion are separately formed, and the positioning portion is formed with a notch into which the upper end portion of the valve stem is slidably inserted. The motor-operated valve according to 1.

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