JP2010164147A - Motor actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a motor actuator for driving a driven member loaded to one side which can prevent damage to a coil spring used as a one-way clutch. <P>SOLUTION: A valve element drive device has the one-way clutch 9 between a rotation transmission member 8 and a crank member 10, so that a loading force applied to a valve element can rotate the crank member 10 counterclockwise CCW prior to the rotation transmission member 8. Although the coil spring 90 relaxes until an end 91 of the coil spring 90 collides with a wall surface situated clockwise CW of a spring end holding portion 858 of a holder 85 of the rotation transmission member 8, the holder 85 of the rotation transmission member 8 is provided with a spring bend reception portion adjoining a bend 92 of the coil spring 90. This can avoid stress concentration on the end 91 of the coil spring 90. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a motor actuator for driving a driven member biased to one side.

  A valve body drive device that opens and closes a valve body biased in a closing direction rotates a rotation transmission member in only one direction by a rotation output from a motor unit, and rotates the rotation transmission member via a one-way clutch. And configured as a motor actuator that transmits to the crank member.

  In such a motor actuator, as a one-way clutch, as shown in FIG. 7, a structure using a coil spring 90 arranged around a shaft portion 851 formed in the rotation transmission member 8 has been proposed (see Patent Document 1). ).

  Here, the coil spring 90 has a distal end bent inward in the radial direction, and an end 91 positioned on the distal end side of the bent portion 92 is inserted into a slit-like spring end holding portion 858 formed in the shaft portion 851. Has been.

In the motor actuator configured as described above, when the rotation transmission member 8 is rotated in one direction (for example, counterclockwise CCW direction), the rotation is transmitted via the spring end holding portion 858 of the rotation transmission member 8. As a result of being transmitted to the end 91 of the coil spring 90, the diameter of the coil spring 90 is expanded and transmitted to the crank member. As a result, the valve body is displaced in the opening direction against the urging force. On the other hand, when the valve body is driven in the closing direction, the urging force applied to the valve body is used to displace the valve body at high speed.
JP 11-325295 A

  In the one-way clutch described in Patent Document 1, when the valve body is moved at high speed in the closing direction by the biasing force, the crank member rotates counterclockwise in advance of the rotation transmission member 8. For this reason, the coil spring 90 is loosened, and the coil spring 90 collides with the wall surface 858a positioned on the clockwise CW side in the spring end holding portion 858. As a result, a large stress is applied to the end 91 of the coil spring 90. Has a problem that it is bent at the bent portion 92.

  In view of the above problems, an object of the present invention is to prevent damage to a coil spring even when a coil spring is used in a one-way clutch in a motor actuator for driving a driven member biased to one side. It is in providing the structure which can be performed.

  In order to solve the above-described problem, in the present invention, a motor actuator for driving a driven member biased to one side, wherein the rotation transmitting member rotates only in one direction by a rotation output from the motor unit. And a crank member to which the rotation of the rotation transmission member is transmitted via a one-way clutch, and the one-way clutch is a shaft portion formed on one side member of the rotation transmission member and the crank member And a cylindrical spring formed on the other side member, and the rotation transmitting member accommodates an end located on the distal end side from a radially bent portion in the coil spring. A holding portion and a spring bent portion receiving portion adjacent to the bent portion on the opposite side to the one direction are provided.

  In the present invention, when the rotation transmitting member is rotated in one direction, the rotation is transmitted to the end of the coil spring via the spring end holding portion of the rotation transmitting member, so that the coil spring has a spring property against the crank member. In contact with the crank member. As a result, the driven member is displaced to the other side against the biasing force. On the other hand, when the driven member is driven to one side (biased side), the driven member is displaced at a high speed using the biasing force applied to the driven member. At this time, since the crank member rotates in one direction in advance of the rotation transmission member, the coil spring is loosened and the end of the coil spring collides with the spring end holding portion of the rotation transmission member. In the present invention, however, since the rotation transmitting member is formed with the spring bent portion receiving portion adjacent to the bent portion of the coil spring, the bent portion of the coil spring contacts the spring bent portion receiving portion of the rotation transmitting member. For this reason, since it can avoid that stress concentrates and is added to the front-end | tip part of a coil spring, a coil spring does not break at a bending part.

  In this invention, the said one side member is provided with the flange part which diameter-expands at the edge part of the said axial part, The annular part by which the said coil spring is located in the said flange part is a taper surface corresponding to the helical shape of the said coil spring It is preferable that the spring bent portion receiving portion is formed by a step portion formed in a discontinuous portion of the tapered surface. With this configuration, in the rotation transmission member, the spring bent portion receiving portion and the shaft portion are formed integrally, and the spring bent portion receiving portion is formed integrally with the flange portion. Is big. For this reason, even if a large force is applied to the spring bent portion receiving portion, the spring bent portion receiving portion is not deformed or damaged. Further, since the spring bent portion receiving portion and the shaft portion are integrally formed, the spring bent portion receiving portion and the spring end holding portion can be formed in a continuous shape. Accordingly, since the spring bent portion receiving portion and the spring end holding portion can be formed in a continuous shape, a step or the like does not occur. Therefore, since a local force is not applied to the coil spring, the coil spring does not break.

  In this invention, it is preferable that the said spring bending part receiving part is formed so that it may be located on the extension line | wire of the central axis of the winding part of the wire which comprises the said coil spring at least. If comprised in this way, since a spring bending part receiving part does not generate | occur | produce the force of the direction which bends a coil spring, a coil spring will not bend.

  In the present invention, the driven member is, for example, a valve body that opens and closes a liquid passage. In this case, the motor actuator is configured as a valve body driving device.

  In the present invention, when the driven member is driven to one side (biased side), the biasing force applied to the driven member is used to displace the driven member at high speed. The end of the coil spring and the spring end holding portion of the rotation transmitting member collide with each other, but the rotation transmitting member has a spring bent portion receiving portion adjacent to the bent portion of the coil spring. The bent portion comes into contact with the spring bent portion receiving portion of the rotation transmitting member. For this reason, since it can avoid that stress concentrates and is added to the front-end | tip part of a coil spring, a coil spring does not break at a bending part.

  An example in which a motor actuator to which the present invention is applied is configured as a valve body driving device will be described with reference to the drawings.

[overall structure]
FIG. 1 is a perspective view showing the external appearance of a valve body drive device (motor actuator) to which the present invention is applied. FIG. 2 is an explanatory view showing the internal structure of the valve body drive device to which the present invention is applied. FIGS. 2 (a) and 2 (b) are respectively an exploded perspective view of the valve body drive device and the valve body drive device. It is a perspective view which shows the motor and wheel train of this. 3 and 4 are explanatory views of a rotation transmission member and a crank member used in the valve body drive device to which the present invention is applied. More specifically, FIGS. 3 (a), 3 (b), and 3 (c) show a state in which the rotation transmission member, the crank member, and the coil spring are combined, a state in which the rotation transmission member and the crank member are disassembled, and rotation. FIGS. 4A, 4B, and 4C are perspective views of the state in which the coil spring is removed from the transmission member as viewed obliquely from above, and FIGS. 4A, 4B, and 4C show a state in which the rotation transmission member, the crank member, and the coil spring are combined. It is the perspective view which looked at the state which decomposed | disassembled and the crank member, and the state which removed the coil spring from the rotation transmission member from diagonally downward.

  1 and 2, a valve body drive device 100 to which the present invention is applied includes a case body 30 including a lower case 31 and an upper case 32, and a crank so as to cover an opening 320 formed in the upper case 32. A member 10 is arranged. The lower case 31 is provided with a motor unit 1 as a drive source, and the rotational force of the motor unit 1 is transmitted to the rotation transmission member 8 via the train wheel 2. As shown in FIG. 2 (b), the train wheel 2 is connected to the first car 24, the second car 25, the third car 26, and the fourth car 27 from the pinion 3 attached to the rotating shaft 1 a of the motor unit 1. In this order.

  As shown in FIGS. 2, 3, and 4, the rotation transmission member 8 is attached to an output wheel 81 including a gear 82 and a rotation shaft 83 that mesh with the fourth wheel 27 and a rotation shaft 83 of the output wheel 81. The holder 85 is provided. A reverse rotation prevention lever 24a (see FIG. 2B) is provided below the first wheel 24, and the reverse rotation prevention lever 24a causes the rotor of the motor unit 1 to rotate only in one direction, while the other. Directional rotation is prevented. For this reason, the rotation transmitting member 8 rotates only in the counterclockwise CCW direction (one direction) and does not rotate in the clockwise CW direction (the other direction). In this embodiment, a small synchronous motor is used as the motor unit 1, but a stepping motor or the like may be used.

  In appearance, the crank member 10 includes a cylindrical body portion 17, a disk portion 18 provided on the upper end side thereof, and a rod engaging portion 19 protruding upward from the outer periphery of the disk portion 18. The rod engaging portion 19 is located at a position shifted from the rotation center axis L of the crank member 10, and the rod 20 is engaged as shown in FIG. The cylindrical body portion 17 includes a cam portion 171 on the outer peripheral surface on the lower end side, and a concave portion 172 is formed in the cam portion 171. The cam portion 171 is in a state in which the convex portion of the movable contact piece S1 of the switch SW shown in FIG. 2 is always in contact, and the switch 5 is turned on or off as the crank member 10 rotates. The switch 5 is used for detecting the rotational position of the rotation transmitting member 8.

  In the crank member 10, a bearing hole 11 having a diameter slightly larger than that of the rotation shaft 83 is opened on the lower end side of the cylindrical body portion 17, and a diameter larger than that of the bearing hole 11 is provided above the bearing hole 11. A coil spring mounting cylindrical portion 12 (cylindrical portion) having an inner diameter of 1 mm is formed. A coil spring 90 is inserted inside the cylindrical portion 12 for mounting the coil spring, and the coil spring 90 constitutes a one-way clutch 9 described later. In the cylindrical portion 12 for mounting the coil spring of the crank member 10, the rotating shaft 83 penetrates inside the coil spring 90, and a cylindrical holder 85 is formed at the tip of the rotating shaft 83 from the upper opening surface side of the crank member 10. Is attached.

  In the rotation transmission member 8, an output shaft attachment hole 850 into which the tip of the rotation shaft 83 is inserted is formed at the center of the holder 85. The holder 85 rotates together with the rotation shaft 83. In order to enable such integral rotation, the distal end portion of the rotating shaft 83 has an elliptical cross section, and the output shaft mounting hole 850 side of the holder 85 has a shape matching it. Further, a screw hole 831 into which the tapping screw 16 is inserted is provided at the tip of the rotating shaft 83, and the holder 85 is moved by the head of the tapping screw 16 by inserting the tapping screw 16 into the screw hole 831 and screwing it in. Fixed to the rotary shaft 83.

  In FIG. 1 and FIG. 2 again, in the valve body drive device 100 of this embodiment, the crank member 10 receives the rotation of the holder 85 and rotates to linearly move the rod 20 engaged with the rod engaging portion 19. Reciprocating motion. A valve mechanism (not shown) exists on the other end side of the rod 20, and the valve body is opened and closed by the linear reciprocation of the rod 20.

  The valve body to be controlled is constantly applied with an urging force (indicated by an arrow F in FIG. 1) to return to the fully closed state. When the valve body is opened, the valve body returns to the fully closed state. The rod 20 moves in the direction of arrow X in FIG. 1 such that the rod 20 pulls the drain valve against the force to be attempted. On the contrary, when the drain valve in the fully open state is fully closed, the rod 20 receives a force for returning to the fully closed state and operates in the direction of the arrow X ′ in FIG. Since such a valve mechanism itself is not the gist of the present invention, illustration and description thereof are omitted.

(Configuration of one-way clutch 9)
As will be described below with reference to FIGS. 3 to 6, in this embodiment, a one-way clutch 9 is configured that uses a coil spring 90 to transmit the rotational force of the holder 85 to the crank member 10 in a detachable manner. ing.

  FIG. 5 is an explanatory view of a one-way clutch used in a valve body drive device to which the present invention is applied, and FIGS. 5A and 5B are a longitudinal sectional view and a transverse sectional view, respectively, of the one-way clutch. FIG. 6 is an explanatory view of members constituting the one-way clutch in the valve body drive device to which the present invention is applied. FIGS. 6 (a), (b), (c), and (d) are respectively used for the one-way clutch. 5 is a bottom view of the holder, a bottom view of the coil spring, a perspective view of the positional relationship between the holder and the coil spring from an obliquely lower side, and a perspective view of a different angle.

  As shown in FIGS. 3 to 7, first, the coil spring 90 is formed with a bent portion 92 that bends an end 91 on the upper end side inward (radially inward) in the central axis direction.

  The holder 85 includes a cylindrical shaft portion 851 and a flange portion 852 that expands in diameter at the upper portion of the cylindrical shaft portion 851, and the annular portion on the lower surface that overlaps the coil spring 90 in the flange portion 852 is a coil spring. It has a tapered surface 854 corresponding to 90 helical shapes. That is, the taper surface 854 has an inclination angle substantially equal to the lead angle of the coil spring 90. A slit-like spring end holding portion 858 into which the end 91 of the coil spring 90 is inserted is formed at one place in the circumferential direction of the shaft portion 851. The end 96 on the lower end side of the coil spring 90 is also bent inward in the radial direction, but the end 96 is in a free state where it does not engage anywhere.

  In the one-way clutch 9 configured as described above, when the holder 85 rotates counterclockwise CCW, the end 91 of the coil spring 90 is pressed against the wall surface 858a located on the clockwise CW side in the spring end holding portion 858. As a result, the coil spring 90 abuts against the inner wall of the coil spring mounting cylindrical portion 12 of the crank member 10. Therefore, the rotation of the holder 85 is transmitted to the crank member 10 by the frictional force between the outer peripheral surface of the coil spring 90 and the inner wall of the cylindrical portion 12 for mounting the coil spring of the crank member 10, and the crank member 10 is counterclockwise CCW. Can be rotated in the direction. However, when the crank member 10 rotates at a higher speed than the rotation transmitting member 8 in the counterclockwise CCW direction, the coil spring 90 is loosened. For this reason, since the frictional force between the coil spring 90 and the inner wall of the coil spring mounting cylindrical portion 12 of the crank member 10 is reduced, the crank member 10 can independently rotate at high speed in the counterclockwise CCW direction.

  Here, in the holder 85, a spring bent portion receiving portion 859 is formed at a position adjacent to the bent portion 92 of the coil spring 90 on the clockwise CW side. In this embodiment, the spring bent portion receiving portion 859 is formed by a step portion 853 formed at the discontinuous portion of the tapered surface 854 in the flange portion 852 in the holder 85, and the clockwise end CW of the spring end portion holding portion 858 is formed. The wall surface 858a located on the side is further extended toward the outer peripheral side. Further, the spring bent portion receiving portion 859 has an inclined shape, similar to the outer peripheral surface shape of the portion from the end portion 91 of the coil spring 90 to the bent portion 92, and the clockwise end CW side of the spring end holding portion 858 is formed. The wall surface which continues toward the outer peripheral side from the wall surface 858a located in this is comprised. In addition, the spring bent portion receiving portion 859 extends to the outer peripheral edge of the flange portion 852, and is positioned on the extension line of the center line 940 of the portion 94 around which the wire constituting the coil spring 90 is wound.

(Operation)
Next, operation | movement of the valve body drive device 100 of this form is demonstrated. First, in the state shown in FIG. 1, the rod 20 is at the position indicated by the arrow X ′, and in this state, the valve body is in a closed state. This state is defined as the origin (0 ° or 360 ° / bottom dead center). From this state, when the motor unit 1 is rotated and the rotation transmitting member 8 is rotated approximately 164 ° counterclockwise CCW, the rotation of the holder 85 is transmitted to the crank member 10 via the coil spring 90, and as a result, the rod 20 is moved to an arrow. Pulled in the direction indicated by X, the valve element is opened. In this state, the motor unit 1 is stopped and the open state of the valve body is maintained.

  Next, in order to close the valve body, the motor unit 1 rotates again. Then, when the rotation transmitting member 8 reaches the position of about 200 ° after passing through the position of 180 ° counterclockwise CCW (top dead center), the rod 20 is arrowed by the biasing force applied to the valve body. It is pulled in the direction of X ′. As a result, the valve body is rapidly displaced in the closing direction, and stops when it reaches the closed position. Meanwhile, the crank member 10 is pulled by the rod 20 and rotates counterclockwise in the CCW direction and stops at a position of about 340 °. During this time, the motor unit 1 rotates and the rotation transmission member 8 also counterclockwise. Although rotating around CCW, the speed is slower than the rotational speed of the crank member 10. Nevertheless, in this embodiment, a one-way clutch 9 is formed between the rotation transmission member 8 and the crank member 10, and in this one-way clutch 9, the crank member 10 precedes the rotation transmission member 8 and counterclockwise CCW. When rotating, the coil spring 90 is loosened, and the frictional force between the outer peripheral surface of the coil spring 90 and the inner wall of the coil spring mounting cylindrical portion 12 of the crank member 10 is reduced. Therefore, since the crank member 10 can rotate at a high speed, the valve body is fully closed in a short time.

  Then, after the valve body is fully closed, the motor unit 1 stops when the rotation transmitting member 8 reaches the position of about 340 ° and returns to the position of 0 ° (bottom dead center).

(Main effects of this form)
As described above, in the valve body drive device 100 of the present embodiment, the one-way clutch 9 is configured between the rotation transmission member 8 and the crank member 10, and therefore the valve body is shifted from the open state to the closed state. At this time, the crank member 10 can be rotated counterclockwise CCW prior to the rotation transmission member 8 by the biasing force applied to the valve body. At this time, the coil spring 90 is loosened, and the end 91 of the coil spring 90 and the wall surface 858a located on the clockwise CW side in the spring end holding portion 858 of the holder 85 of the rotation transmitting member 8 collide with each other. The holder 85 of the member 8 is formed with a spring bent portion receiving portion 859 adjacent to the bent portion 92 of the coil spring 90. For this reason, the bent portion 92 of the coil spring 90 contacts the spring bent portion receiving portion 859 of the holder 85. Accordingly, it is possible to avoid stress from being concentrated on the end portion 91 of the coil spring 90, so that the coil spring 90 does not break at the bent portion 92.

  Further, the spring bent portion receiving portion 859 is formed by a step portion 853 formed at a discontinuous portion of the tapered surface 854 between the cylindrical shaft portion 851 and the flange portion 852. For this reason, in the holder 85 of the rotation transmitting member 8, the spring bent portion receiving portion 859 and the shaft portion 851 are integrally formed, and the spring bent portion receiving portion 859 is also formed integrally with the flange portion 852. Accordingly, the strength of the spring bent portion receiving portion 859 is high. For this reason, even if a large force is applied to the spring bent portion receiving portion 859, the spring bent portion receiving portion 859 is not deformed or damaged. Further, since the spring bent portion receiving portion 859 and the shaft portion 851 are integrally formed, the spring bent portion receiving portion 859 and the spring end holding portion 858 can be formed in a continuous shape. Accordingly, since the spring bent portion receiving portion 859 and the spring end holding portion 858 can be formed in a continuous shape, a step or the like does not occur. Therefore, since a local force is not applied to the coil spring 90, the coil spring 90 is not broken.

  In addition, the spring bent portion receiving portion 859 is located on an extension line of the central axis 940 of the portion 94 around which the wire constituting the coil spring 90 is wound. For this reason, the spring bent portion receiving portion 859 does not generate a force in the direction in which the coil spring 90 is folded, so that the coil spring 90 is not broken.

(Other embodiments)
In the above embodiment, the one-way clutch 9 is configured by arranging the coil spring between the shaft portion on the rotation transmission member 8 side and the cylindrical portion on the crank member 10 side. However, the cylindrical portion is formed on the rotation transmission member 8 side. The one-way clutch may be configured by forming a shaft portion inside the cylindrical portion of the rotation transmission member 8 on the crank member 10 side and arranging a coil spring between the shaft portion and the cylindrical portion. In this case, a structure in which the end of the coil spring is bent radially outward may be employed.

  In the above embodiment, the present invention is applied to the valve body driving device. However, the present invention is applied to a motor actuator other than the valve body driving device as long as it is a motor actuator that drives a driven member biased to one side. You may apply.

It is a perspective view which shows the external appearance of the valve body drive device (motor actuator) to which this invention is applied. It is explanatory drawing which shows the internal structure of the valve body drive device to which this invention is applied. It is explanatory drawing when the rotation transmission member and crank member which were used for the valve body drive device to which this invention is applied are seen from diagonally upward. It is explanatory drawing when the rotation transmission member and crank member which were used for the valve body drive device to which this invention is applied are seen from diagonally downward. It is explanatory drawing of the one-way clutch used for the valve body drive device to which this invention is applied. It is explanatory drawing of the member which comprises a one-way clutch in the valve body drive device to which this invention is applied. It is explanatory drawing of the one-way clutch used for the conventional valve body drive device.

DESCRIPTION OF SYMBOLS 1 Motor part 8 Rotation transmission member 9 One-way clutch 10 Crank member 85 Holder 91 Coil spring end part 92 Coil spring bent part 100 Valve body drive unit 851 Holder shaft part 852 Holder flange part 854 Tapered surface 858 Spring end holding part 859 Spring bent part receiving part

Claims (4)

A motor actuator for driving a driven member biased to one side,
A rotation transmission member that rotates only in one direction by a rotation output from the motor unit;
A crank member to which rotation of the rotation transmitting member is transmitted via a one-way clutch;
Have
The one-way clutch includes a coil spring disposed between a shaft portion formed on one side member of the rotation transmission member and the crank member and a cylindrical portion formed on the other side member,
The rotation transmitting member includes a spring end holding portion that accommodates an end located on a distal end side from a radially bent portion in the coil spring, and a spring that is adjacent to the bent portion on the opposite side to the one direction. A motor actuator comprising: a bent portion receiving portion. The one side member includes a flange portion whose diameter is increased at an end portion of the shaft portion,
In the flange portion, the annular portion on the side where the coil spring is located has a tapered surface corresponding to the helical shape of the coil spring,
The motor actuator according to claim 1, wherein the spring bent portion receiving portion is formed by a step portion formed at a discontinuous portion of the tapered surface.   3. The motor actuator according to claim 1, wherein the spring bent portion receiving portion is formed so as to be positioned at least on an extension line of a central axis of a winding portion of a wire constituting the coil spring.   The motor actuator according to any one of claims 1 to 3, wherein the driven member is a valve body.

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