JP2019100394A - Motor valve - Google Patents

Abstract

To provide a motor valve capable of stabilizing operability without inviting enlargement, weight increase, etc.SOLUTION: Oil reservoir grooves 21h, 15h forming a clearance for storing oil between a guide stem 15 and a valve shaft 21 are provided adjacently to (a lower male screw part 21g) of a male screw part 21e in (an intermediate shaft-like part 21a) of the valve shaft 21, or to a female screw part 15i in (a small diameter upper part 15b) of the guide stem 15, wherein the valve shaft constitutes a screw feeding mechanism.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motorized valve used as a flow control valve or the like in a refrigeration cycle of an air conditioner, a refrigerator, etc., and in particular, the rotational movement of the motor is performed by a screw feed mechanism consisting of an external thread and an internal thread. The present invention relates to a motor-operated valve of a type which converts it into a linear motion and raises and lowers the valve body.

  For example, a motor drive type motorized valve moves a valve body up and down with respect to a valve seat by converting a rotational movement of the motor into a linear movement by a screw feed mechanism including an external thread and an internal thread. Opening and closing (that is, flow control of fluid (refrigerant) passing through the valve port) is performed.

  As a motorized valve of this type, a valve body is provided, a valve shaft having an externally threaded portion formed, a guide stem formed with an internally threaded portion on which the externally threaded portion of the valve shaft is screwed, the valve body contacts and separates A motor having a valve body having a valve seat with a valve seat and provided with the guide stem, a can fixed to the valve body, a rotor for moving the valve shaft up and down with respect to the guide stem, and a stator The screw feed mechanism for raising and lowering the valve body relative to the valve seat is constituted by the female screw portion formed on the guide stem and the male screw portion formed on the valve shaft. It is known (for example, refer to the following patent documents 1 grade).

JP, 2016-089870, A

  By the way, in the conventional motor-operated valve as described above, when the valve is opened and closed, the female screw (fixed screw) of the guide stem constituting the screw feed mechanism (the screw surface) and the male screw (movable screw) of the valve shaft The sliding resistance between the internal thread and the external thread (between the thread surfaces) increases due to aged deterioration, foreign matter biting, etc., and the valve shaft becomes difficult to move. There is a risk of defects. In addition, if the driving torque of the motor is increased to cope with the increase in the sliding resistance described above, there is a concern that the enlargement and the weight increase may occur.

  This invention is made in view of the said subject, Comprising: The place made into the objective is providing the electrically operated valve which can stabilize operativity, without causing enlargement, a weight increase, etc. .

  In order to solve the problems described above, the motor-operated valve according to the present invention basically includes a valve body, and a female screw part in which a male screw part of the valve shaft and a valve shaft having a male screw part formed And a valve body provided with the guide stem, and a can fixed to the valve body, and the valve shaft with the guide shaft. And a motor having a rotor and a stator connected to the valve shaft for rotating with respect to the stem, the valve body being constituted by the female screw portion of the guide stem and the male screw portion of the valve shaft. A screw feed mechanism for raising and lowering with respect to the valve seat is configured, and adjacent to at least one of the male screw portion of the valve stem or the female screw portion of the guide stem, the guide stem and the valve stem Oil reservoir groove to form a gap for storing the oil is characterized by being provided.

  In a preferred aspect, the oil reservoir groove is provided at a position corresponding to the upper end portion of the female screw portion in at least one of the lowest position and the highest position of the valve shaft among the valve shafts.

  In a further preferred aspect, the oil reservoir groove is formed at a position corresponding to the upper end of the female screw at the lowermost position of the valve shaft in the valve shaft from the position corresponding to the upper end of the female screw at the upper end of the female screw at the highest position. It is provided across corresponding positions.

  In another preferred aspect, the oil reservoir groove is provided adjacent to the upper side of the female screw in the guide stem.

  In a further preferred aspect, the bottom surface of the oil reservoir groove has a flat surface perpendicular to the axis or an inclined surface which is lowered toward the central axis.

  In a further preferable aspect, a valve closing direction fixed stopper that defines the most lowered position of the valve stem is provided outside the oil reservoir groove in the guide stem.

  In another preferred embodiment, the oil reservoir groove is provided around or partially around the axis.

  In another preferred aspect, the valve stem is slidably inserted into the guide stem in a lower portion of the screw feed mechanism.

  In a further preferred aspect, the valve shaft is slidably inserted in a bearing hole having a lower portion of the screw feed mechanism larger in diameter than the female screw portion.

  According to the present invention, since the oil reservoir groove is provided adjacent to at least one of the male screw portion of the valve shaft constituting the screw feed mechanism or the female screw portion of the guide stem, the can is filled (for example, filled in a spray). Then, oil (refrigerator oil in the refrigeration cycle) contained in the refrigerant adhering to the valve stem and the guide stem is accumulated in the oil accumulation groove. The oil accumulated in the oil reservoir groove intrudes between the female screw portion and the male screw portion (between the screw surfaces) from the oil reservoir groove due to relative rotation between the female screw portion and the male screw portion, gravity or the like, and the female screw portion and the male screw portion Since it becomes a lubricant (oil) when sliding contact with each other and an increase in sliding resistance between the female screw and the male screw (between screw surfaces) is suppressed, the operability can be stabilized.

  Further, even when foreign matter is caught between the female screw portion and the male screw portion (between screw surfaces), for example, when the female screw portion and the male screw portion are in sliding contact, the foreign material is between the female screw portion and the male screw portion (screw It is discharged together with the oil that has entered the surface, and the increase in sliding resistance between the internal thread and the external thread (between the thread surfaces) due to foreign matter biting is suppressed, which also stabilizes the operability. it can.

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows the fully-closed state of 1st Embodiment of the motor operated valve which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows the fully open state of 1st Embodiment of the electrically operated valve which concerns on this invention. The longitudinal cross-sectional view which shows the fully closed state of the other example (the 1) of the motor operated valve of 1st Embodiment. The longitudinal cross-sectional view which shows the fully open state of the other example (the 1) of the motor operated valve of 1st Embodiment. The longitudinal cross-sectional view which shows the fully closed state of the other example (the 2) of the motor operated valve of 1st Embodiment. The longitudinal cross-sectional view which shows the fully open state of the other example (the 2) of the motor operated valve of 1st Embodiment. The longitudinal cross-sectional view which shows the fully closed state of 2nd Embodiment of the motor operated valve which concerns on this invention. The longitudinal cross-sectional view which shows the fully open state of 2nd Embodiment of the motor operated valve which concerns on this invention. FIG. 8 is a cross-sectional view taken along the line U-U in FIG. 7. (A) is a principal part enlarged longitudinal cross-sectional view of the other example (the 1) of motor-operated valve of 2nd Embodiment, (B) is sectional drawing according to the UU arrow line of FIG. 10 (A). (A) is a principal part enlarged longitudinal cross-sectional view of the other example (the 2) of the motor-operated valve of 2nd Embodiment, (B) is sectional drawing according to the UU arrow line of FIG. 11 (A).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First Embodiment
1 and 2 are longitudinal sectional views showing a first embodiment of the motor-operated valve according to the present invention, wherein FIG. 1 is a fully closed state and FIG. 2 is a fully open state.

  In the present specification, descriptions representing positions, directions such as top, bottom, left, right, front, back, etc. are provided for convenience according to the drawings in order to avoid complicated explanation, and the positions, directions in the actual use state Does not necessarily mean

  Further, in each drawing, the gap formed between the members, the separation distance between the members, and the like are large in comparison with the dimensions of the respective constituent members in order to facilitate understanding of the invention and for convenience in drawing. Or it may be drawn small.

  The motor-operated valve 1 of the illustrated embodiment includes a bottomed cylindrical valve body 10 having an open upper surface, a can 45 whose lower end is hermetically joined to the outer peripheral side of the upper end surface of the valve body 10 by welding or the like, A guide stem 15 with a wedge-shaped disc 18 fixed by welding or the like on the upper end surface inner periphery side, and a female screw 15i formed on the inner periphery (upper half) of the small diameter upper portion 15b of the guide stem 15 The valve shaft 21 has a male screw portion 21e (a lower male screw portion 21g thereof) formed on the outer periphery of the shaft portion 21a screwed together, a rotor 30 integrally fixed to the valve shaft 21 rotatably fixed thereto, and the rotor 30 And a stator 50 fitted on the outer periphery of the can 45 to rotationally drive the motor.

  Here, a stepping motor is constituted by the rotor 30 and the stator 50, and a screw feed mechanism is constituted by the female screw portion (fixed screw portion) 15i of the guide stem 15 and the male screw portion (movable screw portion) 21e of the valve shaft 21. The stepping motor and the screw feed mechanism constitute an elevation drive for raising and lowering the valve shaft 21 (and the valve holder 23 described later) while rotating.

  The valve main body 10 is manufactured by, for example, pressing a metal plate material as a raw material, and a valve seat member 11 having a valve port 11b with a valve seat 11a is fixed to the bottom 10b by brazing or the like The lower part of the guide stem 15 is inserted in the upper part.

  A first inlet / outlet 6 consisting of a pipe joint is joined by brazing or the like to one side of the valve chamber 12 defined in the valve main body 10 (that is, the side wall 10a of the valve main body 10). A second inlet / outlet 7 consisting of a pipe joint is joined to (the lower part of) the member 11 by brazing or the like.

  The valve shaft 21 has an upper small diameter portion 21b on which the connecting member 32 of the rotor 30 is fitted, an intermediate shaft 21a having an external thread 21e, and a lower side than the intermediate shaft 21a (external thread 21e). It has a lower large diameter portion 21c with a crimped portion 21d.

  Specifically, an upper male screw 21f is formed on the upper outer periphery of the intermediate shaft 21a, and a lower male screw 21g is formed on the outer periphery of the lower half thereof. The upper male screw 21f has a valve closing direction described later. The lower male screw portion 21 g is screwed into a female screw portion 15 i formed on the inner peripheral upper half of the small diameter upper portion 15 b of the guide stem 15. Further, between the upper male screw 21f and the lower male screw 21g in the intermediate shaft 21a, an annular and concave oil reservoir is formed to form a gap for storing oil between the guide stem 15 and the valve shaft 21. The groove 21h is used.

  In the present embodiment, the oil reservoir groove 21 h is set to about 1⁄4 of the length of the intermediate shaft portion 21 a in the vertical direction (axis O direction), and the upper end thereof is the valve shaft 21 (valve body 25) or the like. Is at a position corresponding to the upper end portion of (the internal thread portion 15i of the guide stem 15) when in the fully lowered position (the fully closed state shown in FIG. 1). 25) is at a position corresponding to the upper end of (the internal thread 15i of the guide stem 15) in the highest position (the fully open state shown in FIG. 2).

  Further, in this example, since the oil retaining groove 21h is formed after forming the external thread in the intermediate shaft-like portion 21a, the external thread (upper external thread portion 21f) in the upper portion of the oil retaining groove 21h and the external thread (lower portion in the oil retaining groove 21h) The male screw portion 21g) is configured with the same screw phase. Thus, the number of steps for forming the screw can be reduced. Of course, an external thread may be formed after the oil reservoir groove 21h is formed in the intermediate shaft portion 21a. Of course, the upper male screw portion 21 f and the lower male screw portion 21 g may have different screw phases.

  The lower large diameter portion 21c provided on the lower side (that is, the lower side of the screw feed mechanism) of the intermediate shaft portion 21a is set to be slightly shorter than the length in the vertical direction (axis O direction) of the intermediate shaft portion 21a. . The upper portion of the lower large diameter portion 21c is provided at a relatively large diameter (specifically, immediately above the lower circumferential portion of the small diameter upper portion 15b of the guide stem 15 (that is, the lower side of the female screw portion 15i) The valve shaft 21 is moved up and down while being guided by the guide stem 15 by being slidably inserted (in the raising and lowering direction and the rotating direction) into the bearing hole 15c of a larger diameter than the female screw 15i. It has become.

  The ceiling hole portion is connected and fixed to the crimped portion 21d provided on the lower end surface of the lower large diameter portion 21c at the lower end portion of the valve stem 21, and can slide on the large diameter cylindrical body portion 15a of the guide stem 15. The cylindrical valve holder 23 with the ceiling portion 23b inserted therein is held. The upper portion of the valve body 25 is slidably inserted (interpolated) in the vertical direction (up and down direction) and held in the lower portion of the cylindrical portion 23a of the valve holder 23.

  In the present example, the valve body 25 is made of, for example, a metal and used as a raw material of a stepped axial solid member disposed along the vertical direction (direction of the axis O), and the valve seat 11a having an inverted truncated conical surface portion (Inverted frusto-conical valve body portion 25a with its lower portion inserted and seated in the valve port 11b), a short cylindrical portion 25b continuous with the upper portion of the valve body portion 25a, and a cylindrical shape continuous with the upper portion of the short cylindrical portion 25b And a slip-preventing sleeve 25d having a thick and recessed outer periphery fixed by press-fitting, welding or the like on an upper portion of the small-diameter body 25c, and a predetermined portion of the short cylindrical portion 25b A bowl-shaped portion 29 is provided (outwardly) on the. The small diameter body portion 25 c is inserted (through a slight gap) in the through hole 27 a of the bottom plate portion 27 fixed to the lower end portion of the valve holder 23 (the cylindrical portion 23 a thereof). The outer diameter of the small diameter body portion 25c inserted into the through hole 27a is smaller than the diameter of the valve seat 11a (valve port 11b).

  At the lower end portion of (the cylindrical portion 23a of) the valve holder 23, (the retaining sleeve 25d of) the valve body 25 is retained and held with the washer 28 formed of a thin annular disc interposed therebetween, The bottom plate portion 27 formed of a thick plate provided with the holes 27a is held and fixed by caulking, welding or the like.

  On the other hand, a spring receiving member 26 having a hat-shaped cross-sectional outer shape is placed on the upper surface of (the small diameter body 25c of) the valve body 25. The flange 26a of the spring receiving member 26 The valve body biasing spring 24 consisting of a cylindrical compression coil spring for pressing and buffering the valve body is compressed between them, and the valve body 25 is always directed downward by (the biasing force of) the valve body biasing spring 24. It is biased to (valve closing direction).

  The valve shaft 21, the valve holder 23, the valve body 25, and the valve body urging spring 24 substantially integrally rotate in a state (valve open state) in which the valve body 25 is separated from the valve seat 11 a It is raised and lowered while

  The flange portion 29 provided on the valve body 25 and the bottom plate portion 27 constituting the bottom portion of the valve holder 23 provided on the valve holder 23 are provided for the convenience of assembly (the reference position for assembly). And the movable stopper of the stopper mechanism for assembly.

  In this case, in the open state as shown in FIG. 2, the retaining sleeve 25 d of the valve body 25 is in contact with the bottom plate portion 27 with the washer 28 interposed therebetween. The upper surface of the collar portion 29, in other words, the movable stopper (bottom plate portion) 27 and the fixed stopper (ridge portion) 29 of the assembling stopper mechanism are separated by a predetermined distance.

  In addition, in order to set the origin position of the rotor 30 and the valve shaft 21, (the outer peripheral portion of) the upper surface of the small diameter upper portion 15b of the guide stem 15 has a predetermined width, height and depth for the valve closing direction The fixed stopper 55 is provided so as to protrude upward, and the upper portion of the large diameter cylindrical body portion 15a of the guide stem 15 (in other words, around the lower end of the bearing hole 15c) is an open rectangular cross-section having a predetermined width, height and depth. The valve direction fixing stopper 56 is provided so as to protrude downward.

  The valve closing direction movable stopper 35 is screwed onto the upper end portion (that is, the upper male screw portion 21f) of the male screw portion 21e of the valve shaft 21 and is retained and locked to the discoid ceiling portion of the rotor 30. . The valve closing direction movable stopper 35 has a nut portion 35a having a hexagonal outer shape in plan view and which is screwed with the upper male screw portion 21f, and a predetermined portion protruding downward from the nut portion 35a. It consists of a stopper 35s having a rectangular cross section having a width, a height, and a depth.

  In addition, the valve holder 23 is a valve opening contact-locked to the valve opening direction fixing stopper 56 so as to cover the lower portion of the lower large diameter portion 21 c of the valve shaft 21 at the upper portion of (the ceiling portion 32 b thereof). The direction movable stopper 36 is integrally formed. The valve-opening direction movable stopper 36 has a thick-walled cylindrical portion 36a which is mounted on the lower part of the lower large-diameter portion 21c of the valve stem 21, and a predetermined width and height projecting upward from the thick-walled cylindrical portion 36a. , And a stopper portion 36s having a rectangular cross section with a depth.

  The rotor 30 is composed of a cylindrical magnet 31 with a ceiling and a connector 32 integrally coupled to the ceiling. The connector 32 is externally fitted to the upper small diameter portion 21 b of the valve shaft 21 and is closed. It is placed on the valve direction movable stopper 35 and welded and fixed to the upper small diameter portion 21b.

  Here, on the lower surface side of the ceiling portion of the rotor 30, a recessed portion 33 provided with a D cut portion whose both ends are formed in a D shape in plan view is provided, and the D cut portion formed in the recessed portion 33 The arc-shaped side of the nut portion 35a of the movable valve closing direction stopper 35 is fitted into a portion other than the arc-shaped portion, and the other two sides of the nut portion 35a are inserted into the D-cut portion. Are fitted in contact with each other, whereby the rotor 30, the valve closing direction movable stopper 35, and the valve shaft 21 are raised and lowered while integrally rotating.

  On the other hand, on the outer periphery of the can 45, a stator 50 composed of a yoke 51, a bobbin 52, a coil 53, a resin mold 54 and the like is externally fitted. The stator 50 is positioned and fixed at a predetermined position with respect to the valve main body 10 by a positioning fixture (not shown) provided at the bottom of the stator 50.

  Thus, when the rotor 30 is rotated, the valve shaft 21 is rotated integrally with it. At this time, the valve holder 23 is moved up and down with the valve body 25 together with the valve shaft 21 by the screw feed mechanism. , And the passing flow rate of the refrigerant is adjusted.

  The operation of the motor operated valve 1 configured as described above will be described more specifically.

  That is, by supplying a pulse serving as a valve closing direction drive pattern to the stator 50, the rotor 30 and the valve shaft 21 are rotated in one direction (for example, clockwise in plan view), and the female screw 15i and the male screw 21e ( The valve shaft 21 and the valve closing direction movable stopper 35 are rotated (and the valve shaft 21 is guided by the bearing hole 15c of the guide stem 15) by the screw feed mechanism including the lower male screw portion 21g). The valve body 25 (the valve body portion 25a thereof) is seated on the valve seat 11a, and the valve port 11b is closed.

  At this time, the valve closing direction movable stopper 35 is not yet in contact with the valve closing direction fixed stopper 55, the rotation and descent of the rotor 30 and the valve shaft 21 are not stopped, and the valve body biasing spring 24 is located. The pulse supply is continued until the constant compression is performed, whereby the rotor 30, the valve shaft 21, the valve holder 23, and the like are further rotated and lowered while the valve body 25 is seated on the valve seat 11a.

  At this time, since the valve shaft 21 and the valve holder 23 are lowered with respect to the valve body 25, the valve body urging spring 24 is compressed, and thereafter, the compression amount of the valve body urging spring 24 becomes a predetermined amount. When the valve closing direction movable stopper 35 contacts the valve closing direction fixed stopper 55 and is locked, the rotor 30 and the valve shaft 21 reach the lowest position, and the stator 50 has a valve closing direction driving pattern. The lowering of the rotor 30 and the valve shaft 21 is forcibly stopped even if the pulse supply is continued.

  As described above, even after the valve body 25 is seated on the valve seat 11 a and the valve port 11 b is closed, the valve closing direction movable stopper 35 contacts and is locked to the valve closing direction fixed stopper 55. By continuing the rotation and lowering of the rotor 30, the valve shaft 21, and the valve holder 23 until the home position is reached, the valve body urging spring 24 is compressed, so (the valve body 25a of the valve body 25). Is strongly pressed against the valve seat 11a (this state is referred to as a pressure closed state or a fully closed state), so that valve leakage and the like can be reliably prevented.

  On the other hand, when the pulse serving as the valve opening direction drive pattern is supplied to the stator 50 from the home position (pressure closed state or fully closed state shown in FIG. 1) (that is, the lowest position of the valve body 25 etc.) The rotor 30 and the valve shaft 21 are rotated in the opposite direction (for example, counterclockwise in plan view) from the above, and the rotor 30 is rotated by a screw feed mechanism including an internal thread 15i and an external thread 21e (a lower external thread 21g). The valve shaft 21, the valve holder 23, and the valve opening direction movable stopper 36 rotate (and the valve shaft 21 is guided by the bearing hole 15c of the guide stem 15), and accordingly, the valve body 25 is pushed The pressure is reduced, and the valve body biasing spring 24 is expanded by a predetermined amount to return to the original set state, and thereafter (the valve body 25a of the valve body 25) is separated from the valve seat 11a and the valve port 11b is opened. In this case, the lift amount (valve opening degree = flow rate) of the valve 25 is determined in accordance with the number of pulses supplied to the stator 50, and when the pulse supply is further continued, the valve finally becomes fully open (see FIG. 2). The movable valve stopper 36 is brought into contact with and held by the fixed valve opening stopper 56, whereby the rotor 30, the valve shaft 21, and the valve holder 23 are forced to rotate and rise. It is stopped.

  Here, in the motor-operated valve 1 of the present embodiment, the oil reservoir groove 21h is provided adjacent to (the lower male screw portion 21g of) the male screw portion 21e in (the intermediate shaft portion 21a of) the valve shaft 21 that constitutes the screw feed mechanism. Therefore, when operating the motor-operated valve 1 described above, the valve shaft 21 (valve body 25) etc. is fully lowered as shown in FIG. 1 and fully open as shown in FIG. And the oil contained in the refrigerant attached to the valve stem 21 and the guide stem 15 (refrigerator oil in the refrigeration cycle) is contained in the can 45 (for example, filled in the form of a spray). It is stored in the oil reservoir groove 21h. The oil collected in the oil reservoir groove 21h penetrates between the female screw portion 15i and the male screw portion 21e (between the screw surfaces) from the oil reservoir groove 21h due to relative rotation between the female screw portion 15i and the male screw portion 21e or gravity. Since the increase in the sliding resistance between the female screw portion 15i and the male screw portion 21e (between the screw surfaces) is suppressed as a lubricant (oil) when the female screw portion 15i and the male screw portion 21e are in sliding contact with each other. It is possible to stabilize the sex.

  In addition, even when foreign matter is caught between the female screw portion 15i and (the lower male screw portion 21g of (the lower male screw portion 21g) of the female screw portion 15e, when the female screw portion 15i and the male screw portion 21e are in sliding contact, for example Is discharged together with the oil that has entered between the internal thread 15i and the external thread 21e (between the thread surfaces), and there is an increase in the sliding resistance between the internal thread 15i and the external thread 21e (between the thread surfaces) Since it is suppressed, this can also stabilize the operability.

  In the above embodiment, in (the intermediate shaft-like portion 21a of) the valve shaft 21, the oil reservoir groove 21h is at the lowermost position of the valve shaft 21 (the valve body 25) etc. It is provided from the position corresponding to the upper end to the position corresponding to the upper end of (the internal thread portion 15i of the guide stem 15) at the highest position of the valve shaft 21 (valve body 25) etc. And, as shown in FIG. 4, it is provided only in the vicinity of the position corresponding to the upper end of the guide stem 15 (female screw portion 15i) at the lowest position (fully closed state) of the valve shaft 21 (valve body 25) etc. Alternatively, as shown in FIG. 5 and FIG. 6, the valve stem 21 (valve body 25) etc. is at a position corresponding to the upper end of the guide stem 15 (female screw portion 15i) in the fully raised position (fully open state). It may be provided only in the vicinity.

  In the example shown in FIGS. 3 and 4, the vertical length of the oil reservoir groove 21 h is shortened (to the upper side), whereby the vertical length of the lower external thread 21 g screwed to the female thread 15 i of the guide stem 15. In particular, the amount of meshing (screwing length) between the internal thread 15i and the external thread 21e (the lower external thread 21g of the external thread 21e) even in the fully lowered position (fully closed state) of the valve shaft 21 (valve body 25) etc. Can be secured. Further, in the example shown in FIGS. 5 and 6, by shortening the vertical length of the oil reservoir groove 21h (to the lower side), the vertical length of the upper male screw portion 21f can be set longer, and the upper male screw portion 21f is screwed to the female screw 15i of the guide stem 15, the female screw 15i and the male screw 21e (the lower male screw 21g of the male screw 21e) even in the fully lowered position (fully closed state) of the valve shaft 21 (valve body 25) It is possible to secure the amount of engagement (screw length) with the

  In the above embodiment, the oil reservoir groove 21h is formed in an annular shape (that is, around the entire axis O of the valve shaft 21), but it may be formed in a part of the valve axis 21 around the axis O Of course it is good.

Second Embodiment
7 and 8 are longitudinal sectional views showing a second embodiment of the motor-operated valve according to the present invention, FIG. 7 showing a fully closed state, and FIG. 8 showing a fully open state. 9 is a cross-sectional view taken along the line U-U in FIG.

  The shape of the upper end portion of the guide stem 15 is mainly different from that of the motor operated valve 1 of the first embodiment, and the other configuration is substantially the same as that of the motor operated valve 2 of the second embodiment. Therefore, the parts corresponding to the respective parts of the first embodiment are given the same reference numerals, and the redundant description will be omitted, and in the following, the differences will be mainly described.

  In the present embodiment, in order to form a gap for storing oil between the guide stem 15 and the valve shaft 21, the upper end portion of (the small diameter upper portion 15b of the guide stem 15), that is, the female screw constituting the screw feed mechanism An oil reservoir groove 15h having a concaved cross section, the bottom surface of which is a flat surface perpendicular to the axis O, is provided adjacent to the upper side of 15i.

  In this case, for example, the valve closing direction fixing that defines the home position (the most lowered position of the valve shaft 21 (valve body 25 or the like) outside the oil reservoir groove 15h on the upper surface of the small diameter upper portion 15b of the guide stem 15 A stopper 55 is provided.

  Also in the motor-operated valve 2 of the present embodiment, since the oil reservoir groove 15 h is provided adjacent to the female screw portion 15 i in (the small diameter upper portion 15 b of) the guide stem 15 constituting the screw feed mechanism, the motored valve 1 of the first embodiment Similarly to the above, the oil (refrigerant oil in the refrigeration cycle) contained in the refrigerant that fills the can 45 (for example, fills in a spray) and adheres to the valve shaft 21 and the guide stem 15 is the oil reservoir groove 15h (and It is stored in the oil reservoir groove 21 h) on the valve shaft 21 side. The oil collected in the oil storage groove 15h (and the oil storage groove 21h on the valve shaft 21 side) is caused by the relative rotation between the female screw 15i and the male screw 21e, gravity, or the like. Enters into between the female screw part 15i and the male screw part 21e (between the screw surfaces) from the oil reservoir groove 21h on the side, and becomes a lubricant (oil) when the female screw part 15i and the male screw part 21e come in sliding contact Since the increase in sliding resistance between the portion 15i and the male screw portion 21e (between the screw surfaces) can be suppressed, the operability can be stabilized.

  In addition, even when foreign matter is caught between the female screw portion 15i and (the lower male screw portion 21g of (the lower male screw portion 21g) of the female screw portion 15e, when the female screw portion 15i and the male screw portion 21e are in sliding contact, for example Is discharged together with the oil that has entered between the internal thread 15i and the external thread 21e (between the thread surfaces), and there is an increase in the sliding resistance between the internal thread 15i and the external thread 21e (between the thread surfaces) Since it is suppressed, this can also stabilize the operability.

  In the above embodiment, the oil reservoir groove 15 h has a concaved cross section in which the bottom surface is a flat surface perpendicular to the axis O. For example, the oil reservoir groove 15 h is illustrated in FIGS. As described above, the oil reservoir groove 15 h may be formed in a funnel shape including an inclined surface whose bottom surface is lowered toward the central axis O (central portion).

  Further, in the above embodiment, the oil reservoir groove 15h is formed annularly (that is, all around the axis O of the guide stem 15) (see FIG. 9), for example, as shown in FIGS. As a matter of course, the guide stem 15 may be formed in a part around the axis O (in the example shown in FIG. 11, a symmetrical position apart from the axis O of the guide stem 15 by 180 °). is there.

  Further, in the first embodiment, the oil reservoir groove 21h is provided on the side of (the lower male screw portion 21g) of the male screw portion 21e of the valve shaft 21 that constitutes the screw feed mechanism, and in the second embodiment An oil reservoir groove 21h and an oil reservoir groove 15h are provided on both the side of (the lower external thread portion 21g) of the male screw portion 21e of the valve stem 21 and the female screw portion 15i side of the guide stem 15. Naturally, the oil reservoir groove 15h may be provided only on the side of the portion 15i.

  Further, in the above embodiment, the motor-operated valve of the type in which the valve body is seated on the valve seat has been described, but for example, when the valve body is in the fully lowered position (normally fully closed) The same action and effect as described above can be obtained even in a closed valve-less motorized valve in which a gap of a predetermined size is formed between the seat (that is, the valve body is not seated on the valve seat). It is not necessary to do it.

1 Motor-operated valve (first embodiment)
2 Motor-operated valve (second embodiment)
6 first inlet / outlet 7 second inlet / outlet 10 valve body 11 valve seat member 11a valve seat 11b valve port 12 valve chamber 15 guide stem 15h oil reservoir groove 15i female thread 21 valve shaft 21e male thread 21f upper male thread 21g lower male thread 21h Oil sump groove 23 Valve holder 24 Valve body biasing spring 25 Valve body 27 Bottom plate 30 Rotor 35 Moveable stopper 36 for valve closing direction Moveable stopper 45 for valve opening direction Can 50 Stator 55 Fixed stopper 56 for valve closing direction 56 Valve opening direction Fixed stopper

Claims (9)

A valve shaft provided with a valve body and having an external thread formed thereon;
A guide stem formed with an internal thread portion into which the external thread portion of the valve stem is screwed;
A valve body having a valve port with a valve seat to which the valve body contacts and separates, and provided with the guide stem;
A can fixed to the valve body,
A motor having a rotor and a stator coupled to the valve stem for rotating the valve stem relative to the guide stem;
It is a motor-operated valve in which a screw feed mechanism for raising and lowering the valve body with respect to the valve seat is configured by the female screw portion of the guide stem and the male screw portion of the valve shaft,
An oil reservoir groove is formed adjacent to at least one of the male screw portion of the valve stem or the female screw portion of the guide stem to form an oil reservoir for storing oil between the guide stem and the valve stem. A motorized valve characterized by   The oil reservoir groove is provided at a position corresponding to an upper end portion of the female screw portion in at least one of the lowest position and the highest position of the valve shaft among the valve shafts. Motor-operated valve described.   The oil reservoir groove extends from a position corresponding to the upper end portion of the female screw portion at the lowest position of the valve shaft of the valve shaft to a position corresponding to the upper end portion of the female screw portion at the highest position of the valve shaft. The motor operated valve according to claim 2, wherein the motor operated valve is provided.   The motor-operated valve according to claim 1, wherein the oil reservoir groove is provided adjacent to the upper side of the female screw portion in the guide stem.   The motor-operated valve according to claim 4, wherein the bottom surface of the oil reservoir groove has a flat surface perpendicular to the axis or an inclined surface which is lowered toward the central axis.   The motor-operated valve according to claim 4 or 5, wherein a fixed valve-stop direction stopper for defining the lowest position of the valve stem is provided outside the oil reservoir groove in the guide stem.   The motor-operated valve according to any one of claims 1 to 6, wherein the oil reservoir groove is provided around or partially around the axis.   The motor-operated valve according to any one of claims 1 to 7, wherein a lower portion of the screw feed mechanism of the valve shaft is slidably inserted in the guide stem.   The motor-operated valve according to claim 8, wherein a lower portion of the screw feed mechanism of the valve shaft is slidably inserted in a bearing hole having a diameter larger than that of the female screw portion.

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