JP6730751B2 - Motorized valve - Google Patents

Description

The present invention relates to a motor-operated valve that is used as a flow control valve or the like incorporated in a refrigeration cycle of an air conditioner, a refrigerator, etc., and in particular, a valve body is at a lowest position (normally in a fully closed state). At times, 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 valveless valve.

As this type of electrically operated valve, for example, a valve shaft, a guide stem having a cylindrical portion into which the valve shaft is inserted, and a cylindrical shape that is retained and fixed to the lower end portion of the valve shaft and inserted into the guide stem. A valve holder and a coil spring that is inserted into the valve holder so as to be relatively movable and relatively rotatable in the axial direction with respect to the valve shaft, and is attached downward by a coil spring that is compressed between the valve holder and the valve shaft. A valve body that is energized and that is retained and locked by the valve holder, a valve body that has a valve seat portion that contacts and separates the valve body, and that has the guide stem attached and fixed to the valve body; A can, a rotor disposed on the inner circumference of the can, a rotor holder that connects the rotor and the valve shaft via a coupling member that is externally fitted and fixed to the upper end of the valve shaft, and the rotor. A concave portion formed in the rotor holder so that the engaging portion provided in the can fits therein, a stator arranged on the outer periphery of the can for rotating the rotor, and a stator arranged on the inner periphery of the cylindrical portion of the guide stem. A screw for connecting and disconnecting the valve element to and from the valve seat portion, which comprises a female screw member, a fixed screw portion formed on the inner circumference of the female screw member, and a movable screw portion formed on the outer circumference of the valve shaft. The guide mechanism includes a feed mechanism and a stopper mechanism that is disposed on the outer periphery of the cylindrical portion of the guide stem to regulate the vertical movement of the rotor. The stopper mechanism has an upper locking portion and a lower locking portion. A spiral fixed stopper, a first abutment portion that abuts and is engaged with the upper engagement portion, and a second abutment portion that abuts and is engaged with the lower engagement portion are provided. And a slider having a ring shape or a spiral shape incorporated in a spiral portion of the fixed stopper, the slider being configured such that when the rotor rotates, the first contact portion is moved by a pushing portion provided on the rotor. When pushed, the first abutment portion is moved up and down while rotating until the first abutment portion abuts on the upper engagement portion and the second abutment portion abuts on the lower engagement portion. At the origin position where the second contact portion of the slider is brought into contact with the lower locking portion and stopped, a gap of a predetermined size is formed between the valve body and the valve seat portion. The thing is known (for example, refer patent document 1).

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

Japanese Patent No. 5164579

By the way, in the conventional valve-less type motor-operated valve as described above, finally, the rotor fixedly connected to the valve shaft is rotated in the valve-closing direction until the slider is set to the origin position, and the valve body is closed. A gap having 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 origin position depends on the component accuracy of components having a complicated shape such as the valve body and the valve body (the valve seat portion thereof). There is a possibility that the dimensional variation of the gap may become large.

The present invention has been made in view of the above problems, and its object 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. It is to provide a motorized valve that can be suppressed.

In order to solve the problems described above, a motor-operated valve according to the present invention is a valve shaft having a valve body provided at a lower end portion thereof, and the valve shaft is inserted in a state in which the valve shaft is relatively movable and relatively rotatable in an axial direction. A guide bush having a cylindrical portion, a valve body having a valve seat portion for contacting and separating the valve body and having the guide bush attached and fixed, a can joined to the valve body, the inside of the can and the guide A rotor arranged outside the bush, a stator arranged outside the can to rotate and drive the rotor, a cylindrical portion into which the guide bush is inserted, and an insertion portion through which an upper end portion of the valve shaft is inserted. A valve shaft holder that has a ceiling portion having a hole formed therethrough and is rotated integrally with the rotor while supporting the rotor in the can, and separates the valve shaft and the valve shaft holder in the vertical direction. Urging member interposed between the valve shaft and the valve shaft holder to urge the valve shaft and the valve shaft holder to prevent relative movement of the valve shaft holder and the rotor in the up-and-down direction, and It is composed of a fixing member externally fitted and fixed to the upper end portion of the valve shaft so as to connect with the valve shaft holder, and a rotor retainer made of a flat plate member interposed between the fixing member and the rotor. A retaining lock member, a fixing screw portion formed on the guide bush, and a movable screw portion formed on the valve shaft holder, and connected to the valve shaft holder in accordance with rotational driving of the rotor. The valve shaft holder includes a screw feed mechanism for moving the valve body of the valve shaft up and down with respect to the valve seat portion, and a lower stopper mechanism for restricting the downward movement of the valve shaft holder. An electrically operated valve having a gap formed between the valve body and the valve seat portion when in the position, the valve being interposed between the rotor retainer and the fixing member, and in the up-and-down direction of the gap. It is characterized by having a positioning portion having a thickness corresponding to the dimension.

In a preferred form, the rotor retainer and the positioning portion are integrally formed, and the upper end portion of the valve shaft is slidable on the rotor retainer with the positioning portion so as to cross a step formed by the positioning portion. An elongated hole is formed to be inserted into.

In another preferred mode, 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.

According to the motor-operated valve of the present invention, the gap formed between the rotor retainer and the fixed member between the valve body and the valve seat portion when the valve body is at the lowest position corresponds to the vertical dimension. By interposing the positioning portion having a thickness of 5 mm, 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, a complicated valve body or 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, it is possible to suppress the dimensional variation of the gap, thereby improving the controllability of the fluid (refrigerant) flow rate in the low flow rate range. Can be made.

Further, the rotor retainer and the positioning portion are integrally formed, and the rotor retainer with the positioning portion is provided with a long hole through which the upper end of the valve shaft is slidably inserted so as to cross the step formed by the positioning portion. By being formed, it is possible to prevent an increase in the number of parts.

Further, the rotor retainer and the positioning portion are formed separately, and the positioning portion is provided with a notch into which the upper end portion of the valve shaft is slidably inserted. Since the height is further increased, the dimensional variation of the gap can be suppressed more effectively.

1 is a vertical sectional view showing a first embodiment of a motor-operated valve according to the present 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 the sectional view on the AA arrow of (A). It is a figure which shows the valve-shaft holder of the electrically operated valve shown in FIG. 1, (A) is a perspective view, (B) is a front view, (C) is a left side view, (D) is a right side view, (E). Is a top view, (F) is a bottom view, and (G) is a sectional view taken along the line BB of (D). It is a figure where it is used for description of the process of assembling the rotor and the valve shaft holder in the assembly process of the motor-operated valve shown in FIG. 1, and (A) immediately before the valve shaft holder is inserted into the inner cylinder of the rotor. Is a longitudinal cross-sectional view showing the state of FIG. 6 and a cross-sectional view taken along the line C-C of the vertical cross-sectional view. (C) is a vertical cross-sectional view showing a state in which the flat surface portion of the valve shaft holder is inserted into the inner cylinder of the rotor, and a cross-sectional view taken along the line CC of the vertical cross-sectional view. , (D) is a vertical cross-sectional view showing a state in which the protrusion of the valve shaft holder is inserted into the inner cylinder of the rotor, and a cross-sectional view taken along the line C-C of the vertical cross-sectional view. It is a figure which shows the rotor holding|maintenance with a positioning part of the motor-operated valve shown by FIG. 1, (A) is a top view, (B) is the 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 with which the origin position (lowermost position) setting process of a valve body is demonstrated, (A) is a top view and a longitudinal cross-sectional view showing a seated state, B) is a top view and a vertical 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 a sectional view taken on the line EE of (A). FIG. 9A is a diagram which is used for explaining a step of setting the origin position (lowermost position) of the valve body in the assembly process of the motor-operated valve shown in FIG. 8, where (A) is a top view and a vertical sectional view showing a seated state, B) is a top view and a vertical 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, the gaps formed between the members and the distances between the members may be exaggerated for easier understanding of the invention and for convenience of drawing. is there. Further, in the present specification, the description indicating the position and direction such as up and down, left and right is based on the direction arrow display in FIGS. 1 and 8, and does not indicate the position and direction in the actual use state.

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

The electrically 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, a stepping motor 50 including a rotor 51 and a stator 52, The compression coil spring (biasing member) 60, the retaining locking member 70, the screw feed mechanism 28, and the 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 the upper side, and a stepped inverted conical valve body 14 is provided at a 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 such that (the intermediate large diameter portion 12 of) the valve shaft 10 is relatively movable (sliding) in the axis O direction and is relatively rotatable around the axis O. It extends upward from the upper end of the cylindrical portion 21 and has an inner diameter larger than that of the cylindrical portion 21, and 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 are inserted therein. And an installation portion 22. On the outer circumference 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 body 40 in accordance with the rotational driving of the rotor 51. A fixing screw portion (male screw portion) 23 is formed, and at the lower end of the fixing screw portion 23, a fixed stopper body 24 that constitutes one of the lower stopper mechanisms 29 that regulates the downward rotation of the valve shaft holder 30. Is screwed on.

The valve shaft holder 30 includes a cylindrical portion 31 into which the guide bush 20 is inserted, and a ceiling portion 32 having an insertion hole 32a through which an upper end portion of (the upper small diameter portion 11 of) the valve shaft 10 is inserted. Have A movable screw portion (female screw portion) 33 that is screwed with the fixing screw portion 23 of the guide bush 20 to form the screw feeding mechanism 28 is formed on the inner periphery of the cylindrical portion 31 of the valve shaft holder 30. A movable stopper body 34, which constitutes the other side of the lower stopper mechanism 29, is integrally provided on the lower end of the outer periphery of the cylindrical portion 31 so as to project.

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 portion of the valve shaft 10 is provided. The valve shaft 10 and the valve shaft holder 30 are urged in a direction in which the valve shaft 10 and the valve shaft holder 30 are separated from each other 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 (urging member) 60 that urges to is compressed.

The valve body 40 is composed of a metal cylindrical body such as brass or SUS. The valve body 40 has a valve chamber 40a inside, and a first conduit 41a is connected and fixed by brazing or the like to a first lateral opening 41 provided at a side portion of the valve chamber 40a. The insertion hole 43 and the guide bush 20 through which the valve shaft 10 (the intermediate large-diameter portion 12 of the valve shaft 10) is inserted so as to be relatively movable (sliding) in the direction of the axis O and relatively rotatable around the axis O. A fitting hole 44 for fitting and fixing the lower end of the (cylindrical portion 21) is formed, and the second conduit 42a is provided in the vertically oriented second opening 42 provided in the lower portion of the valve chamber 40a. A valve port orifice 46 having a valve seat portion 46a for contacting and separating the valve body 14 is formed on the bottom wall 45 between the valve chamber 40a and the second opening 42 while being connected and fixed by attachment or the like. ..

A flanged plate 47 is fixed to the upper end of the valve body 40 by caulking, 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 flanged plate 47. Has been done.

A rotor 51 is rotatably arranged 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 to rotate the rotor 51. A stator 52 including a bobbin 52b, a stator coil 52c, and a resin mold cover 52d is arranged. 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 a substrate 52f. The existing rotor 51 is adapted to rotate around the axis O.

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

In detail, the rotor 51 is a double pipe including an inner cylinder 51a, an outer cylinder 51b, and a connecting portion 51c connecting the inner cylinder 51a and the outer cylinder 51b, as will be understood well 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 housed inside the outer cylinder 51b. Further, a receiving surface (D-cut surface) 51d formed of a flat surface (at an angular interval of 120 degrees around the axis O) and an inner periphery of the inner cylinder 51a are formed in the center of the receiving surface 51d 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, on the outer periphery of the valve shaft holder 30, a tapered surface 30a made of a truncated cone surface is provided at the upper end thereof (as well understood with reference to FIG. 3) (at 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 circumference of the valve shaft holder 30) 30b is continuously provided downward from the tapered surface 30a, and the flat surface 30b is located farther than the upper edge of the flat surface 30b. A projecting ridge 30c extending downward from the lower position is provided so as to extend downward, and a quadrangular truncated pyramid-shaped tapered portion 30d is provided at an upper end of the projecting ridge 30c. .. Here, the flat surface 30b of the valve shaft holder 30 has a shape complementary to the receiving surface 51d of the rotor 51, and the protrusion 30c of the valve shaft holder 30 is fitted into the vertical groove 51e of the rotor 51. It has a shape that Further, the flat surface 30b (and the ridge 30c formed in the center of the flat surface 30b in the up-down direction) is extended to the middle abdomen of the valve shaft holder 30, and at the lower end of the flat surface 30b. On both sides of the lower portion of the protrusion 30c, locking surfaces 30e for supporting the rotor 51 are formed.

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. 4(A)), 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. 4(B)). Then, a portion (flat surface portion) including the flat surface 30b continuous with the tapered surface 30a is inserted into the inner cylinder 51a (see FIG. 4(C)), and the flat surface 30b of the valve shaft holder 30 is formed. The receiving surface 51d of the rotor 51 is engaged, and the central axis of the valve shaft holder 30 and the rotor 51 and the angular position around the central axis are roughly 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 taper portion 30d provided at the upper end thereof (FIG. 4). (See (D)), the protrusions 30c of the valve shaft holder 30 and the vertical grooves 51e of the rotor 51 are engaged with each other, and the central axis line of the valve shaft holder 30 and the rotor 51 and the angular position around the central axis line are precise. Is aligned with. 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. ..

In this way, 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 flat surface 30b of the valve shaft holder 30, the receiving surface 51d of the rotor 51, the ridge 30c of the valve shaft holder 30, and the rotor 51. By engaging the vertical groove 51e of the above, the valve shaft holder 30 is rotated together with the rotor 51 while supporting the rotor 51 in the can 55.

Above the rotor 51 and the valve shaft holder 30, as shown in FIG. 1, relative movement of the valve shaft holder 30 and the rotor 51 in the vertical direction is prevented (in other words, the rotor 51 with respect to the valve shaft holder 30). (To press downward) and to connect the valve shaft 10 and the valve shaft holder 30, a push nut (fixing member) externally fitted and fixed to the upper end of the valve shaft 10 (the upper small diameter portion 11 thereof) by press fitting, welding or the like. ) 71 and a rotor retainer 72 made of a flat plate member interposed between the push nut 71 and the rotor 51, a retaining locking member 70 is provided. That is, the rotor 51 is sandwiched between the valve shaft holder 30 and the rotor retainer 72, which are biased upward by the biasing force of the compression coil spring 60. The height (vertical direction) from the upper end of the valve shaft holder 30 to the locking surface 30e is the same as the (vertical direction) height 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, as well understood by referring to FIG. 5, a positioning portion 73 having a predetermined thickness H is formed integrally with the rotor retainer 72 (upper left half portion thereof), and The rotor holder 72 with the positioning portion 73 has a long hole 74 through which the upper end 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. Has been formed. In the rotor retainer 72 with the positioning portion 73, as shown in FIG. 1, the positioning portion 73 is 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. The valve body 14 and the valve seat portion 46a are separated by the thickness H of the positioning portion 73 when the valve body 14 is at the lowest position (origin position). A gap is formed in.

The process of setting the origin position (lowermost position) of the valve body 14 by the rotor retainer 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 body 40, etc. assembled, the screw feed 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 rotated and lowered. Then, the valve body 14 provided at the lower end 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 contacts and the valve shaft holder 30 is arranged at the lowest position, the rotor retainer 72 is fitted into the upper end portion of the valve shaft 10 and the push nut 71 is attached. External fitting is fixed by press fitting, welding, etc. At this time, the push nut 71 is fixed while being mounted on a portion of the rotor retainer 72 other than the positioning portion 73 (seated state, see FIG. 6(A)).

Next, with the valve shaft holder 30 still in the lowest position, the valve shaft 10 is pulled up against the biasing force of the compression coil spring 60, and the upper end of the valve shaft 10 is inserted into the slot 74 for positioning. When the rotor retainer 72 with the portion 73 is slid laterally (to the right in the drawing), the positioning portion 73 is interposed between the rotor retainer 72 and the push nut 71, and the pulling force on the valve shaft 10 is released, the push is performed. The nut 71 is arranged on the positioning portion 73 of the rotor retainer 72, and the valve shaft 10 is pulled up 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 the gap 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 retainer 72 may be fixed to each other by welding or the like.

Thus, when the valve body 14 is at the lowest position (origin position), a gap is formed between the valve body 14 and the valve seat portion 46a, the dimension of which in the up-and-down direction corresponds to the thickness H of the positioning portion 73. Will be done.

In addition, the push nut 71 fixed to the upper end of the valve shaft 10 moves the valve shaft holder 30 excessively upward with respect to the guide bush 20 during operation, so that the fixing screw portion 23 of the guide bush 20 and the valve are not moved. In order to prevent the shaft holder 30 from being unscrewed from the movable screw portion 33, a return spring 75, which is a coil spring for urging 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 of (the stator coil 52c of) the stator 52, the valve shaft holder 30 and the valve shaft 10 are rotated integrally with the rotor 51. At this time, the valve feed shaft 28 is moved up and down together with the valve disc 14 by the screw feed mechanism 28 including the fixing screw portion 23 of the guide bush 20 and the movable screw portion 33 of the valve shaft holder 30. The clearance (lift amount) between the valve seat portion 46a and the valve seat portion 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 and the fixed stopper body 24 fixed to the guide bush 20 come into contact with each other and the valve body 14 is at the lowest position, the valve body 14 and the valve seat portion 46a are separated from each other. Since a gap (a required lift amount when closing the valve) 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 rotor retainer 72 and the push nut 71, between the valve body 14 and the valve seat portion 46a when the valve body 14 is at the lowest position. The positioning portion 73 having a thickness corresponding to the dimension of the gap formed in the up-and-down direction is interposed, and the push nut 71 is pressed by the lower stopper mechanism 29 when the valve shaft holder 30 is at the lowest position. When the valve element 14 is disposed on the valve seat 72, the valve element 14 is in contact with the valve seat portion 46a, and the valve shaft 10 is pulled up against the biasing force of the compression coil spring 60, so that the rotor retainer 72 and the push nut 71 are removed. When the positioning portion 73 is interposed between the valve body 10 and the valve body 40, the valve shaft 10 is pulled up by the thickness of the positioning portion 73 with respect to the valve body 40, and the gap is formed between the valve body 14 and the valve seat portion 46a. The respective parts are designed so that they can be separated from each other when they are formed, and the positioning part 73 is interposed between the rotor retainer 72 and the push nut 71, so that the lowest position of the valve body 14, In other words, 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 element 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 is caused. Therefore, the controllability of the flow rate of the fluid (refrigerant) in the low flow rate range can be improved.

Further, since the rotor retainer 72 and the positioning portion 73 are integrally formed, it is possible to prevent an increase in the number of parts.

[Second Embodiment]
FIG. 8 is a vertical sectional view showing a second embodiment of the motor-operated valve according to the present invention.

The difference between the motor-operated valve 1A of the second embodiment and the motor-operated valve 1 of the first embodiment is only the configuration of the rotor retainer and the positioning portion. Therefore, only the configurations of the rotor retainer and the positioning portion will be described in detail, and the same configurations as those of the motor-operated valve 1 shown in FIG. 1 will be denoted by the same reference numerals and detailed description thereof will be omitted. The operation of the motor-operated valve 1A of the present embodiment is also 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 retainer 72A and the positioning portion 73A are separately formed, and the rotor retainer 72A has a round shape into which the upper end of the valve shaft 10A (the upper small diameter portion 11A thereof) is inserted. A hole 74A is bored, and a notch (a notch whose one end is open) 76A is formed in the positioning portion 73A into which the upper end 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 composed of a flat plate-shaped member having a substantially C shape in a plan view, and as shown in FIG. 8, it is provided between the rotor retainer 72A and the push nut 71A. The positioning portion 73A is interposed, so that when the valve body 14A is at the lowest position (origin position), the thickness HA of the positioning portion 73A is between the valve body 14A and the valve seat portion 46aA. A gap is formed.

The step of setting 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, and the rotor. 51A, the fixed stopper body 24A, the valve body 40A, and the like are assembled, the valve feed shaft 28A is formed by using the screw feed mechanism 28A that serves as 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 rotated and lowered. 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. With the fixed stopper body 24A fixed to the bush 20A in contact with the valve shaft holder 30A in the lowest position, the rotor retainer 72A is fitted on the upper end of the valve shaft 10A and the push nut 71A is attached. External fitting is fixed by press fitting, welding, etc. At this time, the push nut 71A is fixed while being placed on the rotor retainer 72A (seated state, see FIG. 10A).

Next, with the valve shaft holder 30A still in the lowest position, the valve shaft 10A is pulled up against the biasing force of the compression coil spring 60A, and the notch 76A is positioned so that the upper end of the valve shaft 10A is inserted. When the portion 73A is slid laterally (to the left in the drawing) and is interposed between the rotor retainer 72A and the push nut 71A and the pulling force for the valve shaft 10A is released, the push nut 71A is placed on the positioning portion 73A. And the valve shaft 10A is pulled up by the thickness HA of the positioning portion 73A with respect to the valve body 40A, whereby the thickness of the positioning portion 73A is increased between the valve body 14A and the valve seat portion 46aA. A gap corresponding to HA (a gap in which the dimension in the vertical direction is HA) is formed (separated state, see FIG. 10B).

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

As a result, when the valve body 14A is at the lowest position (origin position), a gap is formed between the valve body 14A and the valve seat portion 46aA whose vertical dimension corresponds to the thickness HA of the positioning portion 73A. Will be done.

As described above, in the motor-operated valve 1A of the second embodiment, the rotor retainer 72A and the positioning portion 73A are separately formed, and the positioning portion 73A is formed of the flat plate-shaped member, so that the positioning portion 73A. Since the precision of the parts can be further improved, the dimensional variation of the gap can be suppressed more effectively.

1 Motorized valve 10 Valve shaft 14 Valve body 20 Guide bush 21 Cylindrical part 23 Fixing screw part (male screw part)
24 Fixed Stopper 28 Screw Feeding Mechanism 29 Lower Stopper Mechanism 30 Valve Shaft Holder 30a Tapered Surface 30b Flat Surface 30c Protrusion 30d Tapered Part 30e Locking Surface 31 Cylindrical Part 32 Ceiling Part 33 Movable Screw Part (Female Screw Part)
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 mouth orifice 46a Valve seat part 47 Collar 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 lock member 71 push nut (fixing member)
72 Rotor holder 73 Positioning part 74 Slot O O axis

Claims (3)

A valve shaft provided with a valve body at the lower end,
A guide bush having a cylindrical portion in which the valve shaft is inserted so as to be relatively movable and relatively rotatable in the axial direction;
A valve main body having a valve seat portion in which the valve element comes in and out of contact with the guide bush;
A can joined to the valve body,
A rotor disposed inside the can and outside the guide bush,
A stator arranged outside the can for driving the rotor to rotate;
It has a cylindrical portion into which the guide bush is inserted and a ceiling portion in which an insertion hole through which the upper end portion of the valve shaft is inserted is provided, and rotates integrally with the rotor while supporting the rotor in the can Valve shaft holder,
An urging member interposed between the valve shaft and the valve shaft holder so as to urge the valve shaft and the valve shaft holder in a direction away from each other in a vertical direction,
A fixing member externally fitted and fixed to the upper end portion of the valve shaft to prevent relative movement of the valve shaft holder and the rotor in a vertical direction and to connect the valve shaft and the valve shaft holder; A retainer locking member composed of a fixed member and a rotor retainer formed of a flat plate-shaped member interposed between the rotor, and
The valve element 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 which is connected to the valve shaft holder in accordance with rotational driving of the rotor. A screw feed mechanism for moving up and down with respect to the valve seat portion,
A lower stopper mechanism for restricting the downward movement of the valve shaft holder,
An electric valve in which a gap is formed between the valve body and the valve seat portion when the valve shaft holder is at the lowest position,
An electrically operated valve, which is provided between the rotor retainer and the fixing member, and has a positioning portion having a thickness corresponding to a dimension of the gap in a vertical 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 provided with a notch into which the upper end portion of the valve shaft is slidably inserted. The electric valve according to 1.

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