JP6618977B2 - 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, rotates a motor by a screw feed mechanism including a male screw part and a female screw part. The present invention relates to a motor-driven valve of a type that moves up and down by converting into linear motion.

  For example, a motor-driven electric valve converts a rotary motion of a motor into a linear motion by a screw feed mechanism composed of a male screw portion and a female screw portion, thereby raising and lowering the valve body relative to a valve seat. Opening and closing (that is, flow control of the fluid (refrigerant) passing through the valve port) is performed.

  As this type of electric valve, for example, a valve shaft provided with a valve body at the lower end, and 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 portion (valve seat) to which the valve body comes in contact with and separating from the valve body, and the guide bush is attached and fixed; a cylindrical portion in which the guide bush is inserted; and an upper end portion of the valve shaft are inserted. A valve shaft holder connected to and fixed to the valve shaft, and between the valve shaft and the valve shaft holder to urge the valve body in a valve closing direction. An urging member interposed in the motor, a motor having a rotor and a stator for rotating the valve shaft holder with respect to the guide bush, and a fixing screw portion (male screw portion) formed on the outer periphery of the guide bush. Formed on the inner circumference of the valve shaft holder A screw feed mechanism for raising and lowering the valve body of the valve shaft with respect to the valve seat portion (valve seat) in accordance with rotational driving of the rotor, and the valve A fixed stopper body provided on a lower stopper having a female screw portion screwed to the fixed screw portion of the guide bush, and a movable stopper body provided on the valve shaft holder, in order to restrict the rotational movement of the shaft holder. And when the valve body is in the lowest lowered position, a gap of a predetermined size is formed between the valve body and the valve seat portion (valve seat). Those are known (for example, see Patent Document 1).

  In the air conditioner using the valveless type motorized valve as described above, even when the valve body is in the lowest lowered position (normally in a fully closed state), a gap of a predetermined size is provided between the valve seat and the valve seat. For example, when the dehumidifying operation is performed at midnight, it can be operated with the amount of refrigerant reduced without fully closing the motor-operated valve, and the generation of operating noise due to on / off of the motor-operated valve is suppressed. be able to. In addition, the motor-operated valve as described above has an advantage that the bite of the valve body to the valve seat can be surely prevented as compared with a normal valve-closed motor-operated valve.

  Further, as a screw feed mechanism for raising and lowering the valve body with respect to the valve seat, a mechanism using a male screw portion formed on the outer periphery of the valve shaft and a female screw portion formed on the inner periphery of the guide bush is already known. (For example, refer to Patent Document 2).

JP, 2006-217451, A JP 2006-089870 A

  By the way, in this type of electric valve, if a foreign object is caught between the male screw part and the female screw part (between the screw surfaces) constituting the screw feed mechanism, the sliding resistance increases, and the valve shaft becomes difficult to move. Defects may occur.

  In recent years, cases of using a resin material such as PPS for parts having a male screw part and a female screw part constituting a screw feeding mechanism are increasing with a reduction in cost and weight. In this case, it is conceivable to produce a part having the male screw part and the female screw part by molding with a split mold having good molding efficiency. However, when molding with a split mold is adopted, the parting line and weld line (the place where it occurs depending on the gate position differs on the sliding surface (thread surface) of the male thread part and female thread part, but the materials collide with each other during molding. Or a short circuit where the material does not reach sufficiently occurs), which may interfere with sliding and cause problems such as reduced operability.

  This invention is made | formed in view of the said subject, The place made into the objective is to provide the motor operated valve which can suppress the fall of operativity.

In order to solve the above-described problems, the motor-operated valve according to the present invention basically includes a valve shaft provided with a valve body, and a guide in which the valve shaft is relatively movable and relatively rotatable in the axial direction. A valve main body having a valve opening with a valve seat with which the valve body comes in contact with and separating from the bush and provided with the guide bush; a valve shaft holder connected to the valve shaft; and a can fixed to the valve main body; A motor having a rotor and a stator connected to the valve shaft holder for rotating the valve shaft holder with respect to the guide bush, and the valve body of the valve shaft in response to rotational driving of the rotor. A screw feed mechanism having a male screw part and a female screw part provided between the guide bush and the valve shaft holder for moving up and down relative to the valve seat of the valve body, and the valve shaft side moves too much upward When said In order to prevent screwing the screw portion and the female screw portion that deviates, and a return spring provided on the upper end of the valve shaft, at least one of the external thread portion or the internal thread portion, over the elevation direction entire length A longitudinal groove is provided , and the refrigerant is configured to flow through the longitudinal groove .

  In a preferred aspect, the longitudinal groove extends over the entire length of the wall surface of the guide bush or the valve shaft holder in which the male screw portion or the female screw portion is provided.

  In another preferred aspect, the longitudinal groove is formed by a concave surface provided in the female screw portion.

  In another preferred embodiment, the longitudinal groove is constituted by a concave surface or a D-cut surface provided in the male screw portion.

  In another preferred embodiment, the longitudinal groove is formed along a parting line or a weld line of the male screw portion or the female screw portion.

The motor-operated valve according to the present invention basically has a valve shaft provided with a valve body, a guide bush into which the valve shaft is inserted, and a valve opening with a valve seat to which the valve body comes in contact with and separates from the valve shaft. A valve body provided with the guide bush, a can provided in the valve body, a motor having a rotor and a stator for rotating the valve shaft with respect to the guide bush, and a rotational drive of the rotor A screw feed mechanism having a male screw part and a female screw part for raising and lowering the valve body of the valve shaft with respect to the valve seat of the valve body, and the male screw when the valve shaft side moves too far upward And a return spring provided on the upper end side of the valve shaft in order to prevent the threaded portion and the female threaded portion from being disengaged, and at least one of the male threaded portion or the female threaded portion extends vertically through the entire length in the ascending and descending direction groove is provided, before The running through groove is characterized in that it is configured to flow the refrigerant.

  According to the present invention, since the longitudinal groove extending over the entire length in the up-and-down direction is provided in at least one of the male screw portion and the female screw portion constituting the screw feed mechanism, the male screw portion and the female screw portion are not engaged with each other over the entire length in the up-and-down direction. The fluid (refrigerant) flows smoothly through the longitudinal groove, which is a portion (the portion where the screw surfaces are not in contact with each other), and foreign matter that enters between the male screw portion and the female screw portion (between the screw surfaces) Since it can be positively discharged through the longitudinal groove, it is possible to reduce the risk of biting and suppress deterioration in operability.

  Even if a foreign object is caught between the male screw part and the female screw part (between the screw surfaces), the foreign substance is moved by the relative rotation of the male screw part and the female screw part, and the male screw part and the female screw part are engaged with each other. Since the foreign matter is discharged from the non-longitudinal groove, it is possible to reliably suppress a decrease in operability.

  In addition, a longitudinal groove composed of a concave surface or a D-cut surface is formed along the parting line or weld line of the male screw portion or the female screw portion, so that sliding is not hindered by these, and the operability is reduced. It can suppress more reliably.

The longitudinal cross-sectional view which shows 1st Embodiment of the motor operated valve which concerns on this invention. The valve shaft holder shown by FIG. 1 is shown, (A) is a perspective view, (B) is a top view. FIG. 3 is a cross-sectional view taken along the line U-U in FIG. 1. Sectional drawing which follows the VV arrow line of FIG. 3 which shows the valve-shaft holder shown by FIG. The longitudinal cross-sectional view which shows 2nd Embodiment of the motor operated valve which concerns on this invention. FIG. 6 is a cross-sectional view taken along the line U-U in FIG. 5. Sectional drawing which follows the VV arrow line of FIG. 6 which shows the valve-shaft holder shown by FIG. The longitudinal cross-sectional view which shows 3rd Embodiment of the motor operated valve which concerns on this invention. FIG. 9 is a cross-sectional view taken along the line U-U in FIG. 8. The left view which shows the guide bush shown by FIG. The longitudinal cross-sectional view which shows 4th Embodiment of the motor operated valve which concerns on this invention. FIG. 12 is a cross-sectional view taken along the line U-U in FIG. 11. The left view which shows the guide bush shown by FIG.

  Embodiments of the present invention will be described below 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, left and right, etc. are based on the direction arrow display in FIG. 1 and the like, and do not indicate 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 in the illustrated embodiment is used as a flow control valve or the like in a refrigeration cycle such as an air conditioner or a refrigerator, and mainly includes a valve shaft 10 provided with a valve body 14 and a guide. A bushing 20, a valve shaft holder 30, a valve body 40, a can 55, a stepping motor 50 comprising a rotor 51 and a stator 52, a compression coil spring (biasing member) 60, and a fixing member 70 as a stopper 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 above, and a fluid (refrigerant) that flows through the valve port 46 at the lower end portion of the lower small diameter portion 13. A stepped inverted conical valve body 14 for controlling the passage flow rate is integrally formed.

  The guide bush 20 is made of, for example, resin, and 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 cylindrical portion 21 extends upward from the upper end portion of the cylindrical portion 21, has an inner diameter larger than that of the cylindrical portion 21, and is an upper end side of the intermediate large diameter portion 12 and a lower end side of the upper small diameter portion 11 of the valve shaft 10. And an extending portion 22 into which the and are inserted. On the outer periphery of the cylindrical portion 21 of the guide bush 20, one side of a screw feeding mechanism 28 that raises and lowers the valve body 14 of the valve shaft 10 with respect to the valve seat 46 a of the valve body 40 in accordance with the rotational drive of the rotor 51 is configured. A fixing screw portion (male screw portion) 23 is formed. Further, the lower portion of the cylindrical portion 21 (the portion below the fixing screw portion 23) has a large diameter and serves as a fitting portion 27 to the fitting hole 44 of the valve body 40. A lower stopper 25 is screwed to the fixing screw portion 23 (below the valve shaft holder 30), and a lower stopper that restricts the rotational downward movement of the valve shaft holder 30 on the outer periphery of the lower stopper 25. A fixed stopper body 24 constituting one side of the mechanism 29 is integrally projected. In this example, the upper surface 27a of the fitting portion 27 is a stopper portion that regulates the downward movement of the lower stopper 25 (in other words, defines the position of the lower stopper 25 in a seated state described later).

  Further, in this example, a stopper presser 48 is externally attached to the lower stopper 25 attached to the guide bush 20 (the fixing screw portion 23), and the lower stopper 25 is attached to the guide bush 20 (of the guide bush 20). It is non-rotatably connected to the fixing screw portion 23) (detailed later).

  The valve shaft holder 30 is made of, for example, resin (preferably made of resin reinforced with high wear resistance SUS, carbon fiber, or the like in consideration of contact with the fixing member 70), and the guide bush 20 is An insertion hole 32a is inserted through which the cylindrical portion 31 to be inserted and the upper end portion of the valve shaft 10 (the upper small diameter portion 11 thereof) are inserted (with relative movement in the direction of the axis O and relative rotation about the axis O). And a ceiling part 32 provided. A movable screw portion (female screw portion) 33 that forms the screw feed mechanism 28 by screwing with the fixed screw portion 23 of the guide bush 20 is formed at the inner peripheral lower portion of the cylindrical portion 31 of the valve shaft holder 30. Yes. Further, the inner peripheral upper portion of the cylindrical portion 31 is brought into contact (sliding contact) with the outer periphery of the cylindrical extending portion 22 of the guide bush 20, whereby the valve shaft holder 30 is connected to the guide bush 20 (the outer periphery of the guide bush 20). ) Is guided up and down in the direction of the axis O (vertical direction). 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, the top surface of the ceiling portion 32 of the valve shaft holder 30 (the surface facing the flange portion 72 of the fixing member 70 described later) can be seen in a plan view (axis line) as can be understood by referring to FIG. 2 together with FIG. Two convex portions 35 having a substantially fan shape (here, a fan shape having a central angle of about 90 degrees) are integrally formed as viewed in the O direction. Specifically, the two convex portions 35 are disposed around the insertion hole 32a on the upper surface of the ceiling portion 32 (in other words, around the rotation axis O of the valve shaft holder 30) on the opposite side to the axis O (in other words, the valve shaft). While projecting upward (at a position symmetrical with respect to the rotation axis O of the holder 30), in the meantime (in this example, the upper portion of the circumferential end surface 34a of the movable stopper body 34, that is, the direction of the axis O) (The portion including the same position as the one end surface 34a in the circumferential direction of the movable stopper body 34) is cut out (substantially fan-shaped in plan view (here, the central angle is about 90 ° fan-shaped) notch 36).

  Since the contact area of the valve shaft holder 30 with respect to the fixed member 70 is reduced by the convex portion 35, for example, the contact resistance (rotational sliding resistance) when the valve shaft holder 30 contacts the fixed member 70 is reduced.

  Further, for example, when the valve shaft holder 30 is made of a molded product such as resin, the position of the weld line or parting line formed at the time of molding is aligned with the position of the notch 36, that is, the weld line is molded at the time of molding. By providing the notch 36 at a location where a line or parting line is formed, the contact resistance (rotational sliding resistance) can be further reduced, and the flatness of the sliding surface of the valve shaft holder 30 is increased. The axial displacement of the valve shaft 10 can be further suppressed.

  For example, when a gate for injecting molding resin is provided on the opposite side of the movable stopper body 34 in the valve shaft holder 30, as described above, above the movable stopper body 34 (more specifically, the movable stopper body 34). By providing the notch 36 in the upper part of the circumferential end surface 34a of the body 34, the weld 35 and the parting line formed at the time of molding do not exist in the convex portion 35 of the valve shaft holder 30. The contact resistance (rotational sliding resistance) can be further reduced, the flatness of the sliding surface of the valve shaft holder 30 can be increased, and the axial displacement of the valve shaft 10 can be further suppressed.

  In addition, by disposing the convex portion 35 symmetrically with respect to the rotation axis O of the valve shaft holder 30 on the upper surface of the ceiling portion 32 of the valve shaft holder 30, the axial deviation of the valve shaft 10 can be more effectively suppressed. The contact area of the valve shaft holder 30 (the convex portion 35) with respect to the fixed member 70 is further reduced by disposing the convex portions 35 at a plurality of locations around the rotation axis O of the valve shaft holder 30. Is possible.

  It should be noted that the shape, number, position, and the like of the convex portions 35 provided on the upper surface of the ceiling portion 32 of the valve shaft holder 30 are not limited to the illustrated examples, and the convex portions 35 may be omitted. Good.

  Further, between the terrace surface (step part) 15 formed between the upper small diameter part 11 and the intermediate large diameter part 12 of the valve shaft 10 and the lower surface of the ceiling part 32 of the valve shaft holder 30, The valve shaft 10 and the valve shaft 10 are inserted into the upper small-diameter portion 11 of the valve shaft 10 with a disc-shaped pressing plate (washer) 61 disposed on the lower surface side of the ceiling portion 32 of the valve shaft holder 30 interposed therebetween. A cylindrical compression coil spring that biases the valve shaft holder 30 in a direction away from the valve shaft holder 30 in the up-and-down direction (axis O direction), in other words, constantly biases the valve shaft 10 (valve element 14) downward (valve closing direction). (Biasing member) 60 is shrunk.

  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 into which fluid is introduced and led, and a first conduit 41a is connected and fixed to a first lateral opening 41 provided on a side portion of the valve chamber 40a by brazing or the like. An insertion hole through which the valve shaft 10 (the intermediate large-diameter portion 12) can be relatively moved (slided) in the direction of the axis O and is relatively rotatable about the axis O is inserted into the ceiling of the valve chamber 40a. 43 and a lower portion (fitting portion 27) of the guide bush 20 are fitted and fixedly fitted, and a fitting hole 44 is formed, and a second vertical opening 42 provided in the lower portion of the valve chamber 40a Two conduits 42a are connected and fixed by brazing or the like. Further, a stepped valve port 46 having a valve seat 46a with which the valve body 14 contacts and separates is formed in the bottom wall 45 between the valve chamber 40a and the second opening 42.

  An annular bowl-shaped plate 47 is caulked and fixed to the outer periphery of the upper end of the valve body 40 by brazing or the like, and a cylindrical cantilever with a ceiling is formed on a step provided on the outer periphery of the bowl-shaped plate 47. The lower end portion of 55 is hermetically joined by butt welding or the like.

  Further, in this example, a stopper presser 48 that engages with the lower stopper 25 and prevents relative rotation of the lower stopper 25 with respect to the guide bush 20 is disposed on the upper surface (surface on the can 55 side) of the bowl-shaped plate 47. It is fixed.

  The stopper presser 48 is made of a disk-like member made of, for example, a metal member such as brass or SUS by pressing or the like, and has an insertion hole through which the lower stopper 25 is inserted. A plurality of support claws 49 (two of which are shown in FIG. 1) that stand between the holes (in other words, on the outer periphery of the insertion hole) sandwich the lower stopper 25 (two of which are shown). (For the detailed structure, see, for example, Patent Document 1 above).

  The outer peripheral portion of the stopper presser 48 is brought into contact with the flange plate 47 (the upper surface thereof) and joined and fixed by welding, welding, adhesion, or the like, whereby the lower stopper 25 is fixed to the guide bush 20 (fixing screw portion thereof). 23) is connected in a relatively non-rotatable manner.

  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 has a double pipe configuration including an inner cylinder 51a, an outer cylinder 51b, and a connection portion 51c that connects the inner cylinder 51a and the outer cylinder 51b at a predetermined angular position around the axis O. A longitudinal groove 51d extending in the direction of the axis O (vertical direction) is formed on the inner periphery of the inner cylinder 51a (for example, at an angular interval of 120 degrees around the axis O).

  On the other hand, the outer periphery (upper half portion) of the valve shaft holder 30 is provided with a tapered surface portion 30c made of a truncated cone surface at the upper end thereof, as can be understood with reference to FIG. 2, and the lower side of the tapered surface portion 30c. In addition, protrusions 30a extending in the vertical direction are provided (for example, at an angular interval of 120 degrees around the axis O), and upward locking surfaces 30b for supporting the rotor 51 are provided on both lower sides of the protrusions 30a. Is formed.

  In this way, the vertical groove 51d of the inner cylinder 51a of the rotor 51 and the protrusion 30a of the valve shaft holder 30 are engaged, and the lower surface of the inner cylinder 51a of the rotor 51 and the locking surface 30b of the valve shaft holder 30 are engaged. By abutting, the rotor 51 is supported and fixed on the outer periphery of the rotor 51 while being aligned with the valve shaft holder 30, and the valve shaft holder 30 supports the rotor 51 in the can 55 while supporting the rotor 51. Rotated with.

  In this example, the rotor 51 is engaged and supported by the valve shaft holder 30 so that the upper surface of the valve shaft holder 30 is positioned flush with or slightly above the upper surface of the inner cylinder 51a of the rotor 51. Yes.

  On the upper side of the rotor 51 and the valve shaft holder 30, relative movement in the ascending / descending direction of the valve shaft holder 30 and the rotor 51 is prevented (in other words, the rotor 51 is pressed downward against the valve shaft holder 30 to prevent it from coming off). In order to connect the valve shaft 10 and the valve shaft holder 30 together, a fixing member 70 that is externally fitted and fixed to the upper end portion of the valve shaft 10 (the upper small diameter portion 11 thereof) is disposed.

  The fixing member 70 is made of, for example, a metal member such as brass or SUS by pressing, cutting, or the like, and is externally fitted to the upper end portion of the valve shaft 10 (the upper small-diameter portion 11 thereof) to press-fit, weld, and weld. , A stepped cylindrical fixing portion 71 composed of a small-diameter upper portion 71a and a large-diameter lower portion 71b that are bonded and fixed together by bonding or the like, and an inner cylinder 51a of the rotor 51 from the lower end portion of the fixing portion 71 (large-diameter lower portion 71b) And a disk-like flange portion 72 extending outward to the vicinity.

  The lower surface of the flange portion 72 is opposed to the upper surface of the valve shaft holder 30 and the upper surface of the rotor 51 (the inner cylinder 51a), and the convex portion 35 (the upper surface thereof) provided on the upper surface of the valve shaft holder 30. And the rotor 51 (the upper surface of the inner cylinder 51a).

  As described above, the rotor 51 is clamped between the valve shaft holder 30 urged upward by the urging force of the compression coil spring 60 and the fixing member 70 (the outer peripheral portion of the flange portion 72 thereof) to prevent the rotor 51 from coming off. Locked.

  In addition, the valve shaft holder 30 moves too much upward with respect to the guide bush 20 during the operation of the fixing member 70 (the large diameter lower portion 71b of the fixing portion 71) fixed to the upper end portion of the valve shaft 10. In order to prevent the fixed screw portion 23 of the guide bush 20 and the movable screw portion 33 of the valve shaft holder 30 from being disengaged, a return spring comprising a coil spring that biases the valve shaft holder 30 toward the guide bush 20 side. 75 is packaged.

  In the motor-operated valve 1, for example, the valve body 14 is at the lowest lowered position (origin position) in order to prevent the valve body 14 from biting into the valve seat 46a and to ensure controllability in a low flow rate region. Sometimes, a gap of a predetermined size is formed between the valve body 14 and the valve seat 46a.

  The assembly process of the motor-operated valve 1, particularly the origin position (lowermost position) of the valve body 14, will be described in detail. First, the valve shaft 10, guide bush 20, lower stopper 25, compression coil spring 60, valve shaft holder 30. Then, the rotor 51, the valve main body 40, the bowl-shaped plate 47, and the like are assembled. For example, the flange 47 is brazed to the valve body 40, the guide bush 20 is press-fitted and fixed to the valve body 40, and then the lower stopper 25 is screwed to the guide bush 20 (the fixing screw portion 23). Assemble. At this time, the lower stopper 25 is screwed to the guide bush 20 so as to be relatively rotatable. At this stage, the lower stopper 25 may be disposed in contact with the stopper portion 27a of the guide bush 20 or may be disposed at a distance from the stopper portion 27a. Next, the valve body 14 provided at the lower end of the valve shaft 10 contacts (seats) the valve seat 46a, the compression coil spring 60 is slightly compressed, and the movable stopper body 34 and the lower stopper 25 of the valve shaft holder 30 are compressed. The fixed screw portion 23 of the guide bush 20 and the movable screw portion 33 of the valve shaft holder 30 are in contact with the fixed stopper body 24 and until the lower stopper 25 (the lower surface thereof) is in contact with the stopper portion 27a of the guide bush 20. The valve shaft holder 30, the rotor 51, and the valve shaft 10 are lowered while rotating using the screw feed mechanism 28 composed of Then, with the valve shaft holder 30 placed in the lowest position as described above, the fixing member 70 is fitted and fixed to the upper end portion of the valve shaft 10 by press fitting, welding, welding, adhesion, or the like (sitting state).

  Next, from the seated state, an assembly in which the valve shaft 10, the valve shaft holder 30, the rotor 51, the fixing member 70, etc. are integrated is lifted while being rotated using the screw feed mechanism 28 to guide the bushing. After removing from the stopper 20, the stopper holder 48 is placed on the valve body 40 and the bowl-like plate 47 while being covered with the lower stopper 25 so as to drop from above, and the lower stopper 25 is mounted on the guide bush 20 together with the stopper holder 48. The valve is rotated by a predetermined rotation angle in the valve opening direction (for example, counterclockwise in plan view). Then, the stopper presser 48 is joined and fixed to the flange plate 47 of the valve body 40 by welding, welding, adhesion, or the like, and the lower stopper 25 is connected and fixed to the guide bush 20 (the fixing screw portion 23 thereof) so as not to be relatively rotatable. Thereafter, the assembly is assembled to the guide bush 20 using the screw feed mechanism 28 again. As a result, the position of the lower stopper 25 relative to the guide bush 20 of the fixed stopper body 24 changes, so that the movable stopper body 34 of the valve shaft holder 30 and the fixed stopper body 24 of the lower stopper 25 come into contact with each other. Even when in the lowest position, a gap of a predetermined size is formed between the valve body 14 and the valve seat 46a.

  Before attaching the stopper presser 48 to the lower stopper 25, the lower stopper 25 is rotated by a predetermined rotation angle in the valve opening direction with respect to the guide bush 20, and then the stopper presser 48 is externally attached to the lower stopper 25 to provide a valve. It may be bonded and fixed to the bowl-shaped plate 47 of the main body 40.

  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. Between the valve seat 46a and the valve seat 46a is increased or decreased to adjust the passage flow rate of the fluid such as the refrigerant. Even when the movable stopper body 34 of the valve shaft holder 30 and the fixed stopper body 24 of the lower stopper 25 fixed to the guide bush 20 are in contact with each other and the valve body 14 is in the lowest position, the valve body 14 and the valve seat Since a gap is formed with respect to 46a, a predetermined amount of passage flow rate is secured.

  In addition to the above configuration, the following measures are taken in the motor-operated valve 1 of the present embodiment in order to ensure operability.

  That is, as can be understood by referring to FIG. 3 and FIG. 4 together with FIG. 1, the movable screw portion (female screw portion) 33 formed on the inner periphery of the cylindrical portion 31 of the valve shaft holder 30 has an axis O direction (lifting direction). ) A longitudinal groove 33t composed of a concave surface extending over the entire length is formed. In the present example, the two longitudinal grooves 33t are provided on the side opposite to the axis O (in other words, at a position symmetric with respect to the rotation axis O of the valve shaft holder 30).

  As described above, in the motor-operated valve 1 according to the present embodiment, the internal thread portion 33 of the valve shaft holder 30 constituting the screw feed mechanism 28 is provided with the longitudinal groove 33t extending in the up-and-down direction (axis O direction). (Axis O direction) Through the longitudinal groove 33t, which is a portion where the male screw portion 23 of the guide bush 20 and the female screw portion 33 of the valve shaft holder 30 are not engaged with each other over the entire length (a portion where the screw surfaces are not in contact with each other). Fluid (refrigerant) (in the can 55) flows smoothly, and foreign matter that enters between the male screw portion 23 and the female screw portion 33 (between the screw surfaces) can be positively discharged through the longitudinal groove 33t. Therefore, it is possible to reduce the risk of biting and suppress deterioration in operability.

  Even if foreign matter is caught between the male screw portion 23 of the guide bush 20 and the female screw portion 33 of the valve shaft holder 30 (between the screw surfaces), the foreign matter is caused by the relative rotation of the male screw portion 23 and the female screw portion 33. Since the foreign matter is discharged from the longitudinal groove 33t that is moved and the male screw portion 23 and the female screw portion 33 are not meshed with each other, it is possible to surely suppress a decrease in operability.

  Further, for example, when the valve shaft holder 30 is made of a molded product such as resin, the position of the weld line or parting line formed at the time of molding is aligned with the position of the longitudinal groove 33t. By forming the longitudinal groove 33t along the weld line or parting line formed in the female thread portion 33 of the shaft holder 30, sliding is not hindered by the weld line or parting line, and the operability is more reliably lowered. Can be suppressed.

  For example, when a gate for injecting molding resin is provided on the opposite side of the movable stopper body 34 in the valve shaft holder 30, as described above, the inner side of the movable stopper body 34 (more specifically, the movable stopper body 34). By providing the longitudinal groove 33t on the inner end surface 34a in the circumferential direction of the body 34, there is no weld line or parting line formed in the female thread portion 33 of the valve shaft holder 30. As described above, it is possible to more reliably suppress a decrease in operability.

[Second Embodiment]
FIG. 5 is a longitudinal sectional view showing a second embodiment of the motor-operated valve according to the present invention.

  The motor-operated valve 2 of the second embodiment is mainly different from the motor-operated valve 1 of the first embodiment in the shape of the longitudinal groove 33t, and the other configurations are substantially the same. Accordingly, portions corresponding to the respective portions of the first embodiment are denoted by common reference numerals, and redundant description is omitted, and hereinafter, differences will be mainly described.

  In the motor-operated valve 2 of the present embodiment, as can be understood by referring to FIGS. 6 and 7 together with FIG. 5, the longitudinal groove 33t (in other words, a concave surface) extends to the upper side of the female screw portion 33, and the valve It is formed over the entire length of the inner periphery (inner wall surface) of the cylindrical portion 31 of the shaft holder 30 in the direction of the axis O (up and down direction).

  Thus, in the motor-operated valve 2 of the present embodiment, the longitudinal groove 33t extends over the entire length of the inner periphery (inner wall surface) of the cylindrical portion 31 of the valve shaft holder 30 in the direction of the axis O (in the up-and-down direction). Since it extends up to the portion that contacts (slidably contacts) the outer periphery of the extended portion 22 of the guide bush 20 on the upper side of the female screw portion 33, in addition to between the male screw portion 23 and the female screw portion 33 (between the screw surfaces) Foreign matter that enters between the cylindrical portion 31 of the valve shaft holder 30 and the extended portion 22 of the guide bush 20 (between the sliding surfaces) can be easily discharged from the longitudinal groove 33t, and the deterioration in operability is further reliably suppressed. can do.

  Further, for example, when the valve shaft holder 30 is made of a molded product such as resin, a longitudinal groove along a weld line or parting line formed on the inner periphery (inner wall surface) of the valve shaft holder 30 at the time of molding. By forming 33t, sliding is not hindered by the weld line or the parting line, and the deterioration in operability can be more reliably suppressed.

  For example, when a gate for injecting molding resin is provided on the opposite side of the movable stopper body 34 in the valve shaft holder 30, as described above, the inner side of the movable stopper body 34 (more specifically, the movable stopper body 34). By providing a longitudinal groove 33t (over the entire length in the direction of the axis O) on the inner end surface 34a in the circumferential direction of the body 34, the inner periphery (inner wall surface) of the valve shaft holder 30 (internal thread portion 33 and guide bush) Since the weld line and the parting line formed at the time of molding do not exist in the portion (abutting on the outer periphery of the 20 extending portions 22), as described above, it is possible to more reliably suppress the deterioration in operability. it can.

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

  The electrically operated valve 3 of the third embodiment is mainly different from the electrically operated valve 1 of the first embodiment in the formation position of the longitudinal groove 33t, and the other configurations are substantially the same. Accordingly, portions corresponding to the respective portions of the first embodiment are denoted by common reference numerals, and redundant description is omitted, and hereinafter, differences will be mainly described.

  In the motor-operated valve 3 of the present embodiment, the cylindrical portion of the guide bush 20 can be understood by referring to FIGS. 9 and 10 together with FIG. 8 instead of the longitudinal groove 33t formed in the female thread portion 33 of the valve shaft holder 30. A fixed thread part (male thread part) 23 formed on the outer periphery of 21 is formed with a longitudinal through groove 23t formed of a concave surface extending over the entire length in the axis O direction (up and down direction).

  Thus, in the motor-operated valve 3 of the present embodiment, the male thread portion 23 of the guide bush 20 constituting the screw feed mechanism 28 is provided with the longitudinal through-groove 23t extending over the entire length in the up-and-down direction (axis O direction). Similar to the embodiment, the male screw part 23 of the guide bush 20 and the female screw part 33 of the valve shaft holder 30 are not engaged with each other over the entire length in the ascending / descending direction (axis O direction) (the part where the screw surfaces are not in contact with each other). The fluid (refrigerant) flows smoothly (in the can 55) through the longitudinal groove 23t, and foreign matter that enters between the male screw portion 23 and the female screw portion 33 (between the screw surfaces) passes through the longitudinal groove 23t. Therefore, the risk of biting can be reduced, and the deterioration of operability can be suppressed.

  Even if foreign matter is caught between the male screw portion 23 of the guide bush 20 and the female screw portion 33 of the valve shaft holder 30 (between the screw surfaces), the foreign matter is caused by the relative rotation of the male screw portion 23 and the female screw portion 33. Since the foreign matter is discharged from the longitudinal groove 23t that is moved and the male screw portion 23 and the female screw portion 33 are not meshed with each other, it is possible to surely suppress a decrease in operability.

  For example, when the guide bush 20 is made of a molded product such as a resin, the position of the weld line or parting line formed at the time of molding and the position of the longitudinal groove 23t are matched, that is, the guide bush at the time of molding. By forming the longitudinal groove 23t along the weld line or parting line formed in the male screw portion 23, the weld line or parting line formed during molding is formed in the male screw portion 23 of the guide bush 20. Since it does not exist, sliding is not hindered by the weld line or the parting line, and a decrease in operability can be more reliably suppressed.

[Fourth Embodiment]
FIG. 11 is a longitudinal sectional view showing a second embodiment of the electric valve according to the present invention.

  The motor-operated valve 4 of the fourth embodiment is mainly different from the motor-operated valve 3 of the third embodiment in the shape of the longitudinal groove 23t, and the other configurations are substantially the same. Therefore, portions corresponding to the respective portions of the third embodiment are denoted by common reference numerals and redundant description is omitted, and the differences will be described below with emphasis.

  In the motor-operated valve 4 of the present embodiment, as can be understood by referring to FIGS. 12 and 13 together with FIG. 11, the longitudinal groove 23t is a D-cut provided in a male screw portion 23 formed on the outer periphery of the guide bush 20. The longitudinal groove 23t (in other words, the D-cut surface) is extended to the upper side (extension part 22 side) of the male screw part 23, and the cylindrical part 21 and the extension part 22 of the guide bush 20 are formed. Is formed over the entire length of the outer periphery (outer wall surface) of the axis O direction (lifting direction). In the present example, the two longitudinal grooves 23t are provided on the opposite side with respect to the axis O (in other words, at positions symmetrical with respect to the axis O of the guide bush 20).

  Thus, in the motor-operated valve 4 of the present embodiment, the longitudinal groove 23t extends over the entire length of the cylindrical portion 21 of the guide bush 20 and the outer circumference (outer wall surface) of the extending portion 22 in the axis O direction (lifting direction). Since it is provided and extends up to a portion that abuts (slidably contacts) with the inner periphery of the cylindrical portion 31 of the valve shaft holder 30 on the upper side of the male screw portion 23, the second embodiment and the third embodiment are the same as the third embodiment. Of course, the same effect can be obtained.

  In the above embodiment, the male screw part (fixed screw part) 23 formed on the guide bush 20 (the outer periphery) and the female screw part (movable screw part) 33 formed on the valve shaft holder 30 (the inner periphery). The screw feed mechanism 28 for raising and lowering the valve body 14 with respect to the valve seat 46a is configured, but it goes without saying that the fixed screw portion side may be a female screw portion and the movable screw portion side may be a male screw portion ( For example, see Patent Document 2 above).

  In the first and second embodiments, the longitudinal thread 33t is formed in the female screw portion (movable screw portion) 32 formed in the valve shaft holder 30 (inner periphery thereof). In the third embodiment, the guide bush 20 The vertical thread 23t is formed in the male screw part (fixed screw part) 23 formed on the outer periphery of the male screw part. However, if the vertical movement of the valve shaft 10 is not hindered, the female screw part (movable screw part) and the male screw part ( Needless to say, longitudinal grooves may be formed on both of the fixing screw portions.

  Moreover, in the said embodiment, although the guide bush 20 and the valve shaft holder 30 which have the external thread part 23 and the internal thread part 33 which comprise the screw feed mechanism 28 are made from resin, such as PPS, they are made from metal, such as SUS and brass, for example. Of course, it is also good.

  Further, in the above-described embodiment, when the valve body 14 is in the lowest lowered position (normally in a fully closed state), a gap of a predetermined size is formed between the valve body 14 and the valve seat 46a ( In other words, the valve-less motorized valve in which the valve body 14 is not seated on the valve seat 46a has been described. However, for example, an electric valve of the type in which the valve body is seated on the valve seat has the same effect as described above. There is no need to elaborate.

1 Motorized valve (first embodiment)
2 Motorized valve (second embodiment)
3 Motorized valve (third embodiment)
4 Motorized valve (fourth embodiment)
DESCRIPTION OF SYMBOLS 10 Valve shaft 14 Valve body 20 Guide bush 21 Cylindrical part 22 Extension part 23 Fixing screw part (male thread part)
23t longitudinal groove (third and fourth embodiments)
24 fixed stopper body 25 lower stopper 28 screw feed mechanism 29 lower stopper mechanism 30 valve shaft holder 31 cylindrical portion 32 ceiling portion 33 movable screw portion (female screw portion)
33t longitudinal groove (first and second embodiments)
34 movable stopper body 35 convex portion 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 port 46a valve seat 47 bowl-shaped plate 48 Stopper presser 50 Stepping motor 51 Rotor 52 Stator 55 Can 60 Compression coil spring 70 Fixing member 71 Fixing part 72 Flange part O Axis line

Claims (6)

A valve shaft provided with a valve body;
A guide bush in which the valve shaft is inserted so as to be relatively movable and relatively rotatable in the axial direction;
A valve body having a valve opening with a valve seat to which the valve body comes into contact with and separated from the valve body, and the guide bush is provided;
A valve shaft holder coupled to the valve shaft;
A can fixed to the valve body;
A motor having a rotor and a stator coupled to the valve shaft holder for rotating the valve shaft holder relative to the guide bush;
A male screw portion and a female screw provided between the guide bush and the valve shaft holder for raising and lowering the valve body of the valve shaft relative to the valve seat of the valve body in accordance with the rotational drive of the rotor A screw feed mechanism having a portion;
An electric motor for a refrigeration cycle , comprising: a return spring provided on an upper end side of the valve shaft so as to prevent the male screw portion and the female screw portion from being unscrewed when the valve shaft side moves too much upward. A valve,
At least one of the male screw part or the female screw part is provided with a longitudinal groove over the entire length in the ascending / descending direction ,
A motor-operated valve configured to allow a coolant to flow through the longitudinal groove .   2. The electric motor according to claim 1, wherein the longitudinal groove extends over the entire length of the guide bush provided with the male screw portion or the female screw portion or the wall surface of the valve shaft holder in the vertical direction. valve.   The motor-operated valve according to claim 1, wherein the longitudinal groove is configured by a concave surface provided in the female screw portion.   The motor-operated valve according to any one of claims 1 to 3, wherein the longitudinal groove is configured by a concave surface or a D-cut surface provided in the male screw portion.   The motor-operated valve according to any one of claims 1 to 4, wherein the longitudinal groove is formed along a parting line or a weld line of the male screw portion or the female screw portion. A valve shaft provided with a valve body;
A guide bush into which the valve shaft is inserted;
A valve body having a valve opening with a valve seat to which the valve body comes into contact with and separated from the valve body, and the guide bush is provided;
A can provided in the valve body;
A motor having a rotor and a stator for rotating the valve shaft relative to the guide bush;
A screw feed mechanism having a male screw part and a female screw part for raising and lowering the valve body of the valve shaft with respect to the valve seat of the valve body in accordance with the rotational drive of the rotor;
An electric motor for a refrigeration cycle , comprising: a return spring provided on an upper end side of the valve shaft so as to prevent the male screw portion and the female screw portion from being unscrewed when the valve shaft side moves too much upward. A valve,
At least one of the male screw part or the female screw part is provided with a longitudinal groove over the entire length in the ascending / descending direction ,
A motor-operated valve configured to allow a coolant to flow through the longitudinal groove .

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