JP6621788B2 - 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.

  As this type of electric valve, for example, a valve main body having a valve chamber and a valve port formed in the valve chamber, a valve body for opening and closing the valve port, a can protruding from the valve main body, and an outer side of the can A stator coil arranged on the inside of the can, a rotor which is rotated by energization excitation of the stator coil, a screw tube (guide bush) fixed to the valve body, and is rotatable with the rotor A valve shaft holder that opens and closes the valve port by the valve body via the valve shaft by a screw feeding action with the screw tube, and is interposed between the valve shaft holder and the valve shaft, A valve closing spring that urges the valve body in a closing direction of the valve port via a shaft; and the valve shaft holder in a direction in which the valve body opens and closes the valve port in cooperation with the valve closing spring; Stopper (fixed) to prevent relative movement with the rotor The stopper is in contact with the upper surface of the rotor and the valve shaft holder at the disk-shaped portion, and the cylindrical portion is welded and fixed to the upper portion (upper diameter-reduced portion) of the valve shaft. Those are known (for example, see Patent Document 1).

  In this type of conventional motorized valve, in order to securely close the valve port by the valve body, the valve body is normally seated on a valve seat provided in the valve port and the valve port is closed, and then the rotor and The valve shaft holder is rotated downward in the valve closing direction by a predetermined amount (rotation amount), thereby compressing the valve closing spring interposed between the valve shaft holder and the valve shaft, and It presses against the valve seat.

  Specifically, when the motor-operated valve is closed, the stator coil is energized by energizing the stator coil in one direction. As a result, the rotor is rotated, and accordingly, the valve shaft holder is rotated relative to the guide bush (screw tube). Here, for example, the valve shaft holder is lowered by the screw feed mechanism of the guide bush (fixed screw portion thereof) and the valve shaft holder (movable screw portion thereof). Close the valve. At this time, the movable stopper body (upper stopper portion) of the valve shaft holder that constitutes a stopper mechanism that restricts the rotation of the valve shaft holder (and rotor) in the valve closing direction and the downward movement of the valve shaft holder is fixed to the guide bush. It is positioned away from the stopper body (lower stopper body).

  When the stator coil is further energized by exciting in one direction from the above state, the valve stem holder is further lowered by the screw feed mechanism while the valve body closes the valve port (that is, the valve shaft remains stationary). . When the valve shaft holder is lowered by a predetermined amount, the movable stopper body of the valve shaft holder and the fixed stopper body of the guide bush come into contact with each other, and further lowering of the valve shaft holder is restricted by the stopper mechanism. At this time, since the valve closing spring interposed between the valve shaft holder and the valve shaft is compressed, the valve body is strongly pressed against the valve seat to ensure the valve closing property (fully closed state). . At this time, the valve shaft holder is separated from the fixing member (stopper) fixed to the valve shaft by a predetermined gap in the ascending / descending direction.

  On the other hand, when the motor-operated valve is opened from the fully closed state, the stator coil is energized by energizing the stator coil in the other direction. As a result, the rotor is rotated relative to the guide bush fixed to the valve body in the opposite direction, and the valve shaft holder is raised by the screw feed mechanism. Here, since the valve shaft holder is positioned apart from the fixing member fixed to the valve shaft by a predetermined gap, the valve body does not open the valve port during that time (while the valve shaft holder is raised by the predetermined gap). The valve shaft holder rises while it is closed (the valve shaft is stationary).

  When the stator coil is further energized by exciting in the other direction from the above state and the valve shaft holder is raised by the predetermined gap, the valve shaft holder (the upper surface thereof) is fixed to the valve shaft (the disk-shaped portion thereof) Accordingly, the valve shaft holder rises with the valve shaft, and the valve body at the lower end of the valve shaft moves upward to open the valve port.

  Thus, the rotor is rotated by energization excitation to the stator coil, the valve shaft holder is rotated integrally therewith, and the valve shaft is moved up and down along with the valve body, whereby the valve body and the valve are rotated. The clearance (lift amount) between the seat and the seat is increased or decreased to adjust the flow rate of the fluid such as the refrigerant.

JP 2011-208716 A

  By the way, in the conventional motor-operated valve as described above, in the fully closed state, the valve shaft holder is positioned away from the fixing member, and when the valve shaft holder is raised while rotating, the stationary shaft is fixed. (The valve body is slightly pressed against the valve seat at this time), but if the contact resistance (rotational sliding resistance) at this time is large, the rotor is suddenly decelerated, stopped, reversed, etc. May cause this.

  Further, since the rotor that contacts the fixing member together with the valve shaft holder is usually made of a soft material such as a plastic magnet, it may be scraped when sliding with the fixing member.

  Further, in the fixing member, the outer side is slidably contacted more easily than the inner side, and is easily worn.

  The present invention has been made in view of the above problems, and its object is to improve slidability with a fixed member and prevent malfunctions such as rapid deceleration, stop, and reversal of the rotor. Another object of the present invention is to provide an electric valve capable of improving durability.

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 body having a valve seat with a valve seat to which the valve body comes into contact with and away from the valve body and to which the guide bush is mounted and fixed; a valve shaft holder that is externally mounted on the valve shaft; And an urging member for urging the valve body in a valve closing direction, and an urging member fixed to the valve shaft to connect the valve shaft holder to the valve shaft. A fixing member that is brought into contact with the valve shaft holder by a force; a rotor disposed on an outer periphery of the valve shaft holder to rotate the valve shaft holder with respect to the guide bush; and a rotor for rotating the rotor A motor having a stator, and a rotor of the rotor; And a screw feed mechanism provided between the guide bush and the valve shaft holder for raising and lowering the valve body of the valve shaft with respect to the valve seat of the valve body, the fixing member includes a flange portion extending outwardly from the fixed portion and said fixed portion is fixed to the valve shaft, the flange portion has an inner peripheral portion contacting only the valve shaft holder, the upper surface of the rotor It is characterized in Rukoto a peripheral portion at a position located away upward, and restricts the relative movement of the said valve shaft holder rotor from.

In a preferred embodiment, the outer peripheral portion of the flange portion, Ru extends horizontally outwardly.

In another preferred embodiment, the outer peripheral portion of the flange portion is positioned upward in a linear or curved manner as it goes outward.

  In another preferred aspect, the flange portion has a flat surface portion, and the flat surface portion causes the flange portion and the valve shaft holder to be in surface contact.

  In another preferred aspect, the flange portion has a convex portion protruding downward, and the flange portion and the valve shaft holder are brought into point contact by the convex portion.

  According to the present invention, the flange portion of the fixed member is brought into contact only with the valve shaft holder and does not slide into contact with the rotor disposed on the outer periphery of the valve shaft holder. Compared with the conventional motorized valve that slides on both the rotor and the rotor, the contact area with the fixed member can be reduced to improve the slidability and prevent malfunctions such as rapid deceleration, stop, and reversal of the rotor. And the durability of the rotor and the fixing member can be improved.

The longitudinal cross-sectional view which shows the fully closed state of one Embodiment of the motor operated valve which concerns on this invention. The longitudinal cross-sectional view which shows the state by which valve shaft holder and the fixing member were contact | abutted of one Embodiment of the electrically 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. The fixing member shown by FIG. 1 is shown, (A) is a perspective view, (B) is a longitudinal cross-sectional view. The other example (the 1) of the fixing member shown by FIG. 1 is shown, (A) is a perspective view, (B) is a longitudinal cross-sectional view. The other example (the 2) of the fixed member valve-shaft holder shown by FIG. 1 is shown, (A) is a perspective view, (B) is a longitudinal cross-sectional view. The other example (the 3) of the fixed member valve shaft holder shown by FIG. 1 is shown, (A) is a perspective view, (B) is a longitudinal cross-sectional view. The other examples (the 4) of the fixed member valve axis holder shown in Drawing 1 are shown, (A) is a perspective view, (B) is a longitudinal section, and (C) is a bottom view.

  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 indications of FIGS. 1 and 2 and do not indicate the positions and directions in the actual use state.

  1 and 2 are longitudinal sectional views showing an embodiment of a motor-operated valve according to the present invention. FIG. 1 is a fully closed state (a state where a rotor and a valve shaft holder are in a lowest lowered position), and FIG. It is a figure which shows the state by which the valve-shaft holder and the fixing member were made to contact | abut.

  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 and a lower large-diameter portion 12 from the upper side, and controls the flow rate of fluid (refrigerant) flowing through the valve port 46 at the lower end portion of the lower large-diameter portion 12. For this purpose, a stepped (here, three-stage) inverted conical valve body 14 is integrally formed.

  The guide bush 20 includes a cylindrical portion 21 that is inserted in a state in which the valve shaft 10 (the lower large-diameter portion 12 thereof) is relatively movable (slidable) in the direction of the axis O and is relatively rotatable about the axis O, and The cylinder portion 21 extends upward from the upper end portion, has an inner diameter larger than that of the cylindrical portion 21, and is an extension in which the upper end side of the lower large diameter portion 12 and the lower end side of the upper small diameter portion 11 of the valve shaft 10 are inserted. And an installation part 22. 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 and fixed to the fixing screw portion 23 (below the valve shaft holder 30), and the rotation of the valve shaft holder 30 is restricted to the outer periphery of the lower stopper 25. A fixed stopper body 24 constituting one side of the lower stopper mechanism 29 to be performed is integrally projected.

  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. At the same time, 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. 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.

  In addition, the upper 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 plan view as can be understood by referring to FIG. 3 together with FIGS. The 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 direction of the axis O). 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. The slidability between the valve shaft holder 30 and the fixing member 70 at the time of valve opening is improved, and malfunctions such as rapid deceleration, stop, reversal and the like of the rotor 51 are suppressed, and the shaft displacement of the valve shaft 10 is suppressed. Can do.

  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 a notch 36 at the upper end portion 34a of the body 34 in the circumferential direction, there is no weld line or parting line formed on the convex portion 35 of the valve shaft holder 30 during molding. 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 portion) 13 formed between the upper small diameter portion 11 and the lower 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 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 lower large-diameter portion 12) is inserted in the ceiling of the valve chamber 40a so as to be relatively movable (slidable) in the direction of the axis O and relatively rotatable about the axis O. 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 fixed to the upper end portion of the valve body 40 by caulking, brazing, or the like, and a cylindrical can 55 with a ceiling is formed on a step provided on the outer periphery of the bowl-shaped plate 47. The lower end of each is hermetically joined by butt welding or the like.

  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 along the axis O direction (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 formed of a truncated cone surface at the upper end thereof, as can be understood with reference to FIG. 3, 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, the relative movement of the valve shaft holder 30 and the rotor 51 in the ascending / descending direction is restricted (in other words, the rotor 51 is prevented from coming off and locked to the valve shaft holder 30). In addition, in order to connect the valve shaft 10 and the valve shaft holder 30, 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, header processing, or the like. As can be understood by referring to FIG. 4 together with FIGS. A stepped cylindrical fixing portion 71 composed of a small-diameter upper portion 71a and a large-diameter lower portion 71b that are fitted and fixed by press fitting, welding, welding, adhesion, etc. A substantially disc-shaped flange portion 72 extending outward from the lower end portion of the fixing portion 71 (the large-diameter lower portion 71b) to the vicinity of the upper side of the inner cylinder 51a of the rotor 51.

  In this example, the flange portion 72 is formed to be slightly inclined so as to be positioned upward as it goes outward, and the lower surface of the flange portion 72 includes the upper surface of the valve shaft holder 30 and the rotor 51 (inside And the inner peripheral portion of the lower surface of the flange portion 72 is brought into contact with the convex portion 35 (the upper surface thereof) provided on the upper surface of the valve shaft holder 30, so that the flange portion 72 72 is separated from the upper surface of the rotor 51 (inner cylinder 51a) by a predetermined separation distance (separation distance Ha in the fully closed state shown in FIG. 1, separation distance Hb <Ha in the state shown in FIG. 2). ) Only on the top (away).

  Note that the inclination angle of the flange portion 72 and the separation distance between the flange portion 72 and the rotor 51 (the inner cylinder 51a) can be adjusted even when the valve shaft 10 or the like is inclined, for example. The dimensions are set such that the cylinder 51a) does not come into contact with the cylinder 51a).

  Further, in this example, the portion where the flange portion 72 and the valve shaft holder 30 (the convex portion 35) abut on each other as viewed in the ascending / descending direction (axis O direction) is below the valve shaft holder 30 (the ceiling portion 32 thereof). The outer diameter of the large-diameter lower portion 71b of the fixing portion 71 is set so as to be at a position different from the compression coil spring 60 arranged at (in detail, slightly outside the compression coil spring 60).

  As described above, the rotor 51 is latched and locked between the valve shaft holder 30 biased upward by the biasing force of the compression coil spring 60 and the fixing member 70 (the outer peripheral portion of the flange portion 72 thereof). The

  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 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.

  In the motor-operated valve 1 of the present example, when the valve shaft 10 is lowered and the valve body 14 is seated on the valve seat 46a, the fixed stopper fixed to the movable stopper body 34 of the valve shaft holder 30 and the guide bush 20 is provided. Then, the rotor 51 is further rotated by further energization excitation to the stator 52 (stator coil 52c thereof), and the valve shaft holder 30 is lowered while rotating integrally therewith. As a result, 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, that is, the rotation and lowering of the valve shaft holder 30 are stopped by the lower stopper mechanism 29. The compression coil spring 60 interposed between the valve shaft holder 30 and the valve shaft 10 is compressed, and the valve body 14 is strongly pressed against the valve seat 46a. It has become to so that.

  More specifically, when the motor-operated valve 1 is closed, the stator coil 52c is energized in one direction to be excited. As a result, the rotor 51 is rotated, and accordingly, the valve shaft holder 30 is rotated relative to the guide bush 20. Here, the valve shaft holder 30 is lowered by the screw feed mechanism 28 including the guide bush 20 (the fixed screw portion 23 thereof) and the valve shaft holder 30 (the movable screw portion 33 thereof). The valve body 14 descends and seats on the valve seat 46a to close the valve port 46. At this time, the movable stopper body 34 of the valve shaft holder 30 constituting the lower stopper mechanism 29 and the fixed stopper body 24 of the guide bush 20 are positioned apart (state shown in FIG. 2).

  When the stator coil 52c is further energized by energizing the stator coil 52c from the above state, the valve body 14 closes the valve port 46 (that is, the valve shaft 10 remains stationary) and the screw feed mechanism 28 causes the valve shaft to be closed. The holder 30 is further lowered (against the biasing force of the compression coil spring 60). When the valve shaft holder 30 is lowered by a predetermined amount, the movable stopper body 34 of the valve shaft holder 30 and the fixed stopper body 24 of the guide bush 20 come into contact with each other, and further lowering of the valve shaft holder 30 is restricted by the lower stopper mechanism 29. The At this time, since the compression coil spring 60 interposed between the valve shaft holder 30 and the valve shaft 10 is compressed, the valve body 16 is strongly pressed against the valve seat 46a, and the valve closing property is ensured. (Fully closed state shown in FIG. 1). At this time, the valve shaft holder 30 (the convex portion 35 thereof) is separated from the fixing member 70 fixed to the valve shaft 10 by a predetermined gap Hc (= Ha−Hb) in the ascending / descending direction.

  On the other hand, when the motor-operated valve 1 is opened from the fully closed state, the stator coil 52c is energized in the other direction to be excited. As a result, the rotor 51 is rotated relative to the guide bush 20 fixed to the valve body 40 in the opposite direction, and the valve shaft holder 30 is raised by the screw feed mechanism 28. Here, since the valve shaft holder 30 (the convex portion 35 thereof) is positioned away from the fixing member 70 fixed to the valve shaft 10 by a predetermined gap Hc, during that time (the valve shaft holder 30 is raised by the predetermined gap Hc). The valve shaft holder 30 is raised while the valve body 14 is seated on the valve seat 46a and the valve port 46 is closed (the valve shaft 10 is stationary).

  When the stator coil 52c is further energized and excited from the above state and the valve shaft holder 30 rises by the predetermined gap Hc, the convex portion 35 (the upper surface thereof) provided on the ceiling portion 32 of the valve shaft holder 30. Comes into contact with the fixing member 70 (the lower surface of the flange portion 72 thereof) fixed to the valve shaft 10, and accordingly, the valve shaft holder 30 rises (with rotation) with the valve shaft 10, The valve body 14 at the lower end moves upward and the valve port 46 is opened.

  As described above, in the motor-operated valve 1 according to the present embodiment, the flange portion 72 of the fixing member 70 is brought into contact with only the valve shaft holder 30, and the rotor 51 disposed on the outer periphery of the valve shaft holder 30. Since the sliding member does not slide, the contact area with the fixing member 70 can be reduced and the slidability can be improved, for example, compared with a conventional electric valve in which the fixing member slides on both the valve shaft holder and the rotor. It is possible to prevent malfunctions such as rapid deceleration, stop, and reverse, and improve the durability of the rotor 51 and the fixing member 70.

  In order to improve the slidability, the flange portion 72 of the fixing member 70 may be plated or coated. As an example in this case, there is a process of plating or coating a material containing Teflon (registered trademark), carbon or the like.

  In the above embodiment, the flange portion 72 of the fixing member 70 is formed so as to be positioned linearly upward as it goes outward. However, the shape of the flange portion 72 is not limited to the illustrated example. Of course. For example, as shown in FIG. 5, the flange portion 72 may be formed in a shape that warps so as to be curvedly positioned upward (becomes a convexly curved surface) as it goes outward. Further, for example, as shown in FIGS. 6 and 7, a (circular) flat surface portion 73 is formed on the inner peripheral portion of the flange portion 72, and the flange portion 72 and the valve shaft holder are formed by the flat surface portion 73. 30 may be in surface contact. For example, as shown in FIG. 8, convex portions (four convex portions at equal angular intervals in the circumferential direction in the example shown in FIG. 8) that protrude downward are provided on the inner peripheral portion of the flange portion 72. The flange portion 72 and the valve shaft holder 30 may be in point contact with each other by the projection 74.

  In the above-described embodiment, the type of motor-operated valve in which the valve body 14 is seated on the valve seat 46a has been described. For example, when the valve body is in the lowest lowered position (normally in a fully closed state), the valve body The same effect as described above can be obtained even in a closed valve type motor-operated valve in which a gap of a predetermined size is formed between the valve seat and the valve seat (that is, the valve body does not seat on the valve seat). Needless to say.

DESCRIPTION OF SYMBOLS 1 Motorized valve 10 Valve stem 14 Valve body 20 Guide bush 21 Cylindrical part 23 Fixing screw part (male screw part)
24 fixed stopper body 28 screw feed mechanism 29 lower stopper mechanism 30 valve shaft holder 30a protrusion 30b locking surface 30c taper surface portion 31 cylindrical portion 32 ceiling portion 33 movable screw portion (female screw portion)
34 movable stopper body 35 convex portion 36 notch 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 50 stepping Motor 51 Rotor 52 Stator 55 Can 60 Compression coil spring (biasing member)
70 fixing member 71 fixing part 71a small diameter upper part 71b large diameter lower part 72 flange part 73 flat surface part 74 convex part O axis

Claims (5)

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 seat with a valve seat to which the valve body comes in contact with and away from the valve body, and the guide bush is mounted and fixed;
A valve shaft holder sheathed on the valve shaft;
An urging member interposed between the valve shaft and the valve shaft holder and urging the valve body in a valve closing direction;
In order to couple the valve shaft holder to the valve axis, is fixed to the valve shaft, a fixing member for Sesse said valve shaft holder by the biasing force of the biasing member,
A motor having a rotor disposed on the outer periphery of the valve shaft holder and a stator for rotationally driving the rotor to rotate the valve shaft holder with respect to the guide bush;
A screw feed mechanism 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 motor-operated valve comprising:
The fixing member has a fixing portion fixed to the valve shaft and a flange portion extending outward from the fixing portion,
The flange portion, the outer peripheral portion of the inner peripheral portion contacting only the valve shaft holder distanced upward from the upper surface of the rotor, and in a position to restrict the relative movement of the said valve shaft holder rotor electric valve, characterized in Rukoto with and. The motor-operated valve according to claim 1, wherein the outer peripheral portion of the flange portion extends horizontally outward . The motor-operated valve according to claim 1 , wherein the outer peripheral portion of the flange portion is positioned so as to be linearly or curvedly upward as it goes outward.   The said flange part has a flat surface part, The said flange part and the said valve-shaft holder are surface-contacted by this flat surface part, The Claim 1 characterized by the above-mentioned. Motorized valve.   The flange part has a convex part protruding downward, and the flange part and the valve shaft holder are in point contact with the convex part. The motor-operated valve according to one item.

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