JP5046046B2 - Self-locking clutch - Google Patents

Description

  The present invention relates to a self-locking clutch that transmits a driving force from the input side to the output side and automatically locks and does not transmit it to the input side when the driving force is input from the output side.

  Conventionally, a drive shaft such as a motor is fitted in the center of the shaft and rotated by a rotational drive of the drive shaft, a cylindrical collar that encloses the outer periphery of the drive side rotating body, and a drive side rotation inside the collar It is arranged on the same axis as the body, has a contact surface that can contact the drive side rotating body in the rotation direction, and is formed so that the distance from the inner peripheral surface of the collar varies depending on the position in the rotation direction. There is a self-locking clutch including a driven side rotating body having a control surface on the outer peripheral surface, and a rolling element that is disposed between the inner peripheral surface of the collar and the control surface and is movable along the inner peripheral surface of the collar. It was.

  In this self-locking clutch, when the drive-side rotator rotates and the contact surface and the drive-side rotator contact, the rolling element is separated from the control surface and can move along the inner peripheral surface of the collar. It is configured to be. For this reason, the driving side rotating body and the driven side rotating body can rotate together. Further, when the driven side rotating body does not rotate and the driven side rotating body rotates, the rolling element is configured to be held between the inner peripheral surface of the collar and the control surface. For this reason, further rotation of the driven-side rotator is prohibited. Furthermore, the contact area between the control surface and the rolling element when the rolling element is clamped is configured to be long.

  According to this technique, when the driving side rotating body rotates, the driving side rotating body and the driven side rotating body are allowed to rotate integrally. When the driven side rotating body does not rotate and the driven side rotating body rotates, the rotation of the driven side rotating body is automatically prohibited. For this reason, it has been said that reliable self-locking is possible.

  Furthermore, since the contact range between the control surface and the rolling element is increased, the lock holding force can be improved without increasing the size of the self-locking clutch.

JP 2001-336550 A

  However, the self-locking clutch disclosed in Patent Document 1 has a large number of parts and a complicated structure, so that the cost is high and the operation reliability may be low.

  In view of the above circumstances, an object of the present invention is to provide a self-locking clutch that can be surely self-locked with a small number of parts.

  A first characteristic configuration of the self-locking clutch according to the present invention is an input shaft that is rotationally driven around a rotational axis, and is engaged with the input shaft and relatively moved with a predetermined stroke with respect to the input shaft. And an output shaft that rotates together with the input shaft at both ends of the stroke range, and is pivotally supported by a stationary member, swings on a surface along the rotation shaft core, and can be engaged with and disengaged from the output shaft. A restricting member, a neutral return means for biasing the restricting member to a neutral state engaged with the output shaft, and a sliding engagement with the outer surface of the output shaft, along the stroke direction of the output shaft. When following the relative movement, and when the output shaft is located at a position other than both ends of the stroke range, the restricting member is positioned at a swing restricting position that restricts the neutral state, and the input shaft is driven to rotate. The output shaft is at both ends of the stroke range. When location is in that a slider member positioned swing allowable position for allowing the oscillation of the regulating member in the rotational drive direction of the input shaft from the neutral state.

  According to this configuration, the input shaft, the output shaft, the restricting member, the neutral return means, and the slider member are provided. When the output shaft is located at a position other than both ends of the stroke range, the slider member is positioned at the swing restricting position. However, the regulating member is regulated to the neutral state, and the engagement between the regulating member and the output shaft is not released. For this reason, even if the driving force from the opposite side to the input shaft acts on the output shaft, the output shaft does not rotate in any direction.

  On the other hand, when the output shaft is positioned at both ends of the stroke range, the slider member is positioned at the swing allowable position, and the regulating member can swing in the rotational drive direction of the input shaft. For this reason, the engagement between the regulating member and the output shaft can be released in the rotational drive direction, and the output shaft can rotate integrally with the input shaft. At this time, since the regulating member cannot swing in the direction opposite to the direction in which the input shaft and the output shaft can rotate integrally, even if the driving force from the opposite side to the input shaft acts on the output shaft in the opposite direction, The engagement between the regulating member and the output shaft is not released, and the output shaft does not rotate. Further, when the driving force from the side opposite to the input shaft acts on the output shaft in a direction in which the input shaft and the output shaft can rotate together, the output shaft rotates.

  With this configuration, a self-locking clutch capable of transmitting power only in one direction can be realized with a small number of parts and a simple structure. Further, since the self-locking is performed by the engagement between the output shaft and the swing member, the self-locking is not easily released even when the load on the output shaft increases. Therefore, a highly reliable self-locking clutch can be obtained at low cost.

  Furthermore, since the neutral return means is provided, the regulating member is biased to the neutral state. Therefore, when the input shaft and the output shaft are not rotating, the restricting member does not swing, and the engagement between the restricting member and the output shaft is not unexpectedly disengaged. Therefore, the swinging member is always in a position engaged with the output shaft, and even if the driving force from the opposite side to the input shaft acts on the output shaft, the rotation of the output shaft can be immediately controlled. In addition, the position of the self-locking clutch and the degree of freedom of the installation direction are less likely to be affected by gravity and external vibration.

  A second characteristic configuration of the self-locking clutch according to the present invention is an input shaft that is rotationally driven around a rotational axis, and is engaged with the input shaft and relatively moved with a predetermined stroke with respect to the input shaft. And an output shaft that rotates integrally with the input shaft at both ends of the stroke range, and a sliding engagement with the outer surface of the output shaft to follow the relative movement of the output shaft along the stroke direction. And a regulating member that swings on a surface along the pivot axis and that can be engaged with and disengaged from the output shaft, and a neutral return means that biases the regulating member into a neutral state that engages the output shaft; When the output shaft is fixed to a stationary member and the output shaft is located at a position other than both ends of the stroke range, the regulating member is regulated to the neutral state, and the output shaft is moved within the stroke range by rotating the input shaft. When positioned at both ends of the neutral From state in that a slider member to permit oscillation of the regulating member in the rotational drive direction of the input shaft.

  This characteristic configuration is such that in the configuration of the self-locking clutch according to the first characteristic configuration, the regulating member follows the relative movement of the output shaft, and the slider member is fixed to the stationary member. For this reason, basically, even if a driving force from the opposite side of the input shaft acts on the output shaft, the input shaft and the output shaft are integrated without locking the self-locking and rotating the output shaft. When it is desired to rotate, the self-locking clutch that releases the one-way self-lock and enables the input shaft and the output shaft to rotate integrally can be realized with a small number of parts and a simple structure. Further, since the self-locking is performed by the engagement between the output shaft and the swing member, the self-locking is not easily released even when the load on the output shaft increases. Therefore, a highly reliable self-locking clutch can be obtained at low cost.

  A third characteristic configuration of the self-locking clutch according to the present invention is that the neutral return means is a spring provided in the regulating member.

  According to this configuration, since the neutral return means is a spring provided on the restriction member, it is easy to attach to the restriction member, and the degree of freedom of the installation position and the installation direction of the neutral return means is increased. Further, the biasing force can be easily adjusted by adjusting the elastic force of the spring.

  Hereinafter, an embodiment of a self-locking clutch C according to the present invention will be described with reference to the drawings.

(overall structure)
As shown in FIG. 1, the self-locking clutch C includes an input shaft 1, an output shaft 2, a regulating member 3, a neutral return means (not shown), and a slider member 4. The input shaft 1 is rotationally driven around the rotational axis L. The output shaft 2 is screwed to the input shaft 1 and moves relative to the input shaft 1 with a predetermined stroke, and rotates integrally with the input shaft 1 at both ends of the stroke range. The regulating member 3 is pivotally supported by a stationary member (not shown), engages with the output shaft 2 in a neutral state, swings on a surface along the rotation axis L, and can be engaged with and disengaged from the output shaft 2. The neutral return means urges the regulating member 3 to the neutral state. The slider member 4 is slidably engaged with the outer surface of the output shaft 2 and follows the relative movement of the output shaft 2 along the stroke direction.

  Further, the slider member 4 is located at a rocking restricting position for restricting the restricting member 3 to a neutral state when the output shaft 2 is located at a position other than both ends of the stroke range. When 2 is positioned at both ends of the stroke range, it is positioned at a rocking allowable position that allows rocking of the regulating member 3 from the neutral state to the rotation driving direction of the input shaft 1.

(Input shaft)
As shown in FIG. 2, the input shaft 1 is a member having a cylindrical shaft portion 11 and a cylindrical screw portion 12 having a diameter larger than that of the shaft portion 11, and is rotated at a fixed position by input of driving force. It is rotated around the axis L. A screw is cut on the outer periphery of the screw portion 12 from the front end portion 13 to the rear end portion 14, and this screw meshes with a screwing groove 25 of the output shaft 2 described later.

(Output shaft)
As shown in FIG. 2, the output shaft 2 includes a gear portion 21 on the opposite side to the input shaft 1, a base portion 22 on the input shaft 1 side, and a sliding groove 23 formed on the outer peripheral surface of the base portion 22. It is a cylindrical member and can be rotated around a rotation axis L. As shown in FIG. 3B, the output shaft 2 is formed with a screwing groove 25 centered on the rotation axis L, and the screw portion 12 and the screwing groove 25 are related to a screw nut. It is in. An end of the output shaft 2 on the side of the input shaft 1 is closed with a plate 26 so that the input shaft 1 does not deviate from the output shaft 2. An insertion hole 27 is formed in the plate 26 so as to allow the shaft portion 11 to pass therethrough.

  The gear portion 21 includes a tooth portion 21a along the rotation axis L on the outer peripheral surface, and the rotation of the output shaft 2 by the rotation drive of the input shaft 1 is transferred to the next member via the tooth portion 21a. Communicated. The sliding groove 23 is a groove having an arc cross section formed around the outer peripheral surface of the base portion 22, and a slider member 4 described later is slidably engaged therewith.

  A support hole 24 is formed at the end of the output shaft 2 opposite to the input shaft 1, and a support member (not shown) fixed to a stationary member such as a housing is slidably inserted. Thus, since the output shaft 2 is held by the input shaft 1 and the support member, the self-lock clutch C operates stably.

(Regulatory member)
As shown in FIG. 2, the regulating member 3 includes a quadrangular columnar arm portion 31 extending in the direction of the rotation axis L, and a pivot shaft formed on the side surface of the arm portion 31 opposite to the output shaft 2. 32 and an engaging portion 33 formed on the side surface of the arm portion 31 on the output shaft 2 side. The restricting member 3 is pivotally supported via a pivot shaft 32 on a surrounding strong stationary member, for example, a housing (not shown) that houses the self-locking clutch C.

  As shown in FIG. 3A, the pivot shaft 32 of the pivot shaft 32 is perpendicular to the rotation axis L and is positioned at the approximate center of the sliding groove 23. When the regulating member 3 is in a state along the rotation axis L, the locking portion 33 is locked between the tooth portion 21a and the tooth portion 21a of the gear portion 21 as shown in FIG. With this configuration, the regulating member 3 swings on a surface along the rotation axis L and can be engaged with and disengaged from the output shaft 2.

  The regulating member 3 is urged in a state along the rotation axis L by a spring as a neutral return means (not shown). This state is the “neutral state” in the present invention. The spring is a torsion spring or a leaf spring, and is preferably provided between the pivot shaft 32 or the arm portion 31 and the housing.

(Slider member)
As shown in FIGS. 1 and 2, the slider member 4 slides along the engagement portion 41 slidably engaged with the slide groove 23 and the arm portion 31, and is constant in the direction of the rotation axis L. And a regulating portion 42 having a length. The cross-sectional shape of the engaging portion 41 corresponds to the cross-sectional shape of the sliding groove 23 and is curved in the longitudinal direction so as to follow the shape around the outer peripheral portion of the sliding groove 23. Further, although not shown, a rail extending in the direction of the rotation axis L is fixed to the housing, and holds a surface of the slider member 4 opposite to the arm portion 31. Therefore, the slider member 4 is held between the arm portion 31 and the rail, does not rotate with the output shaft 2, and can move in the direction of the rotation axis L following the relative movement of the output shaft 2.

(Self-locking clutch operation)
The operation of the self-locking clutch C configured as described above will be described with reference to the drawings. 3 to 5, (a) is a plan view of the self-locking clutch C, (b) is a sectional view in the direction of the rotation axis L of the self-locking clutch C, and (c) is a view of the output shaft 2. It is the side view of the self-locking clutch C seen from the side.

  As shown in FIG. 3, the self-locking clutch C is assembled so that the center of the slider member 4 and the swing axis SL are aligned when the screw portion 12 is located at the center of the screwing groove 25.

  At this time, the regulating surface 42a of the slider member 4 is in contact with the regulated surface 31a of the regulating member 3 with the oscillation axis SL interposed therebetween, and the oscillation of the regulating member 3 is regulated. For this reason, the restricting member 3 does not swing, and the engaging portion 33 is engaged between the tooth portion 21a and the tooth portion 21a of the gear portion 21, and the rotation of the output shaft 2 is restricted.

  Further, since the screw portion 12 and the screwing groove 25 are in a screw nut relationship, when the input shaft 1 is rotationally driven, the output shaft 2 is translated along the rotational axis L. In the present embodiment, when the input shaft 1 is rotationally driven in the direction of the white arrow, the output shaft 2 is relatively moved in the right direction. Therefore, the output shaft 2 moves relative to the input shaft 1 in the stroke from the state of FIG. 4B to the state of FIG.

  The length of the regulating surface 42a in the direction of the rotational axis L is made to coincide with the length of the stroke. For this reason, as shown in FIG. 4, when the input shaft 1 is rotationally driven in the direction of the white arrow and the tip 13 reaches the end of the screwing groove 25 opposite to the input shaft 1, the restriction surface 42a All are located on the input shaft 1 side with respect to the swing axis SL. Therefore, the restricting member 3 can swing clockwise as indicated by a one-dot chain line. At this time, since the output shaft 2 does not move to the right any further, when the input shaft 1 is further rotated in the direction of the white arrow, the tooth portion 21a causes the locking portion 33 to move as shown in FIG. The output shaft 2 can rotate with the input shaft 1 while kicking and releasing the locking of the locking portion 33.

  In this state, when the rotational drive of the input shaft 1 is stopped, the regulating member 3 is reliably returned to the neutral state by the biasing force of the spring, and the locking portion 33 is between the tooth portion 21a and the tooth portion 21a. Lock. Therefore, even if the driving force in the direction opposite to the white arrow acts on the output shaft 2 from the side opposite to the input shaft 1, the output shaft 2 does not rotate.

  Further, when the driving force in the direction of the white arrow acts on the output shaft 2 from the side opposite to the input shaft 1, the output shaft 2 rotates. However, when the stationary torque of the input shaft 1 is large, the output shaft 2 moves relative to the left while rotating, so that a part of the regulation surface 42a is positioned on the opposite side of the swing shaft core SL from the input shaft 1. Then, the rotation of the swing member is restricted. Therefore, the output shaft 2 cannot instantaneously rotate.

  On the other hand, as shown in FIG. 5, when the input shaft 1 is driven to rotate in the direction of the white arrow and the rear end portion 14 reaches the end of the screwing groove 25 on the input shaft 1 side, the entire restriction surface 42 a is reached. Is positioned on the opposite side of the input shaft 1 with respect to the swing axis SL. Therefore, the restricting member 3 can swing counterclockwise as indicated by a one-dot chain line. At this time, since the output shaft 2 does not move to the left any further, when the input shaft 1 is further rotated in the direction of the white arrow, the tooth portion 21a causes the locking portion 33 to move as shown in FIG. The output shaft 2 can rotate with the input shaft 1 while kicking and releasing the locking of the locking portion 33.

  In this state, when the rotational drive of the input shaft 1 is stopped, the restricting member 3 is reliably returned to the neutral state by the biasing force of the spring, and the locking portion 33 is between the tooth portion 21a and the tooth portion 21a. Lock. Therefore, when the driving force in the direction opposite to the white arrow acts on the output shaft 2 from the side opposite to the input shaft 1, the rotation of the output shaft 2 is immediately restricted.

  Further, when the driving force in the direction of the white arrow acts on the output shaft 2 from the side opposite to the input shaft 1, the output shaft 2 rotates. However, when the stationary torque of the input shaft 1 is large, the output shaft 2 moves relative to the right while rotating, so that a part of the regulation surface 42a is positioned on the input shaft 1 side of the swing axis SL. Rotation of the swing member is restricted. Therefore, the output shaft 2 cannot instantaneously rotate.

  That is, as shown in FIG. 3, the position where the restricting surface 42a sandwiches the swing axis SL is the “swing restricting position” in the present invention. As shown in FIG. 4 or FIG. A position on either side with respect to the swing axis SL is a “swing allowable position”.

  Furthermore, since the end faces 42b and 42c on both sides of the restricting portion 42 in the direction of the rotation axis L are chamfered in an R shape, the restricting member 3 swings smoothly along the R shape of the end face 42b or the end face 42c. can do. Moreover, since the end surface 42b and the end surface 42c are R-shaped, the swing angle range of the regulating member 3 can be quickly expanded by a minute movement of the regulating member 3.

  Thus, when the input shaft 1 and the output shaft 2 rotate together, the locking portion 33 continues to be kicked by the tooth portion 21a, so that the wear of the locking portion 33 and the tooth portion 21a is prevented. Both parts should be made of wear-resistant material. Moreover, in order to prevent the contact sound of both members, it is good to add elastic performance to the latching | locking part 33. FIG.

  In the present embodiment, in order to increase the locking force, the locking portion 33 and the tooth portion 21a are configured to engage with each other, but the configuration is not limited thereto. For example, a friction surface may be provided instead of the locking portion 33 and the base 22 may be formed long, and the friction surface and the base 22 may be engaged by friction. In this case, since the gear part 21 is not an engagement target, the tooth part 21a is prevented from being worn.

  In the present embodiment, the length of the regulating surface 42a in the direction of the rotational axis L is made to coincide with the stroke length, but the stroke may be set larger. In this case, there is some allowance until the output shaft 2 is positioned at the end of the stroke after the slider member 4 reaches the swing allowable position. For this reason, it is possible to absorb an assembly error or the like when assembling so that the screw portion 12 is positioned at the center of the screwing groove 25. Moreover, some play can be provided in the screw nut structure, and the manufacturing accuracy can be relaxed.

(Another embodiment 1)
In the above embodiment, the slider member 4 is slidably engaged with the output shaft 2 and the regulating member 3 is pivotally supported by the stationary member. However, as shown in FIGS. 6 and 7, the regulating member 3 is connected to the output shaft. The slider member 4 may be fixed to the stationary member by sliding and tilting in a swingable manner.

  In this embodiment, the restricting member 3 includes an arm portion, an engaging portion 34 that is slidably engaged with the sliding groove 23, and a pivot shaft 32 that rotatably connects the arm portion 31 and the engaging portion 34. And a locking portion. The slider member 4 includes a restriction portion 42 and a fixed shaft 43 that is fixed to a stationary member such as a housing. Furthermore, like the rail in the above-described embodiment, a member that prevents the restriction member 3 from rotating together with the output shaft 2 is necessary. For example, although not shown in the figure, a concave rail along the rotation axis L fixed to the housing or the like and a convex member movable along the rail are provided. What is necessary is just to connect to a rocking shaft so that rotation is possible.

  The self-locking clutch C according to the present embodiment is only slightly different from the above-described embodiment in the relative relationship between the slider member 4 and the regulating member 3, and has substantially the same operation and effect as those described above. Is omitted.

(Another embodiment 2)
In the above-described embodiment, the rotation from the output shaft 2 side is restricted by the self-locking, but a configuration for manually releasing the self-locking may be provided. When the self-lock clutch C according to the present invention is applied to a power back door of a vehicle, it is preferable to have a configuration for arbitrarily releasing the self-lock, such as when the back door is automatically opened and then manually closed. is there.

The perspective view of the self-locking clutch which concerns on this invention 1 is an exploded perspective view of a self-locking clutch according to the present invention. It is a figure which shows a self-locking clutch when a slider member exists in a rocking | fluctuation control position, (a) is a top view, (b) is sectional drawing, (c) is the side view seen from the output-shaft side FIG. 5 is a diagram showing the self-locking clutch when the slider member is in a swing allowable position on the input shaft side, where (a) is a plan view, (b) is a cross-sectional view, and (c) is a side view as viewed from the output shaft side. FIG. 4 is a diagram showing a self-locking clutch when the slider member is in a swing allowable position on the side opposite to the input shaft, where (a) is a plan view, (b) is a cross-sectional view, and (c) is a side view seen from the output shaft side. Figure Exploded perspective view of a self-locking clutch according to another embodiment Plan view of a self-locking clutch according to another embodiment

Explanation of symbols

C Self-locking clutch L Rotating shaft core 1 Input shaft 2 Output shaft 3 Restricting member 4 Slider member

Claims (3)

An input shaft that is pivotally driven about a pivot axis;
An output shaft that is screwed to the input shaft and moves relative to the input shaft with a predetermined stroke, and rotates integrally with the input shaft at both ends of the stroke range;
A regulating member pivotally supported by a stationary member, swinging on a surface along the pivot axis, and capable of being engaged with and disengaged from the output shaft;
Neutral return means for biasing the restricting member to a neutral state to be engaged with the output shaft;
When the output shaft follows the relative movement of the output shaft along the direction of the stroke by slidingly engaging with the outer surface of the output shaft, and the output shaft is located at a position other than both ends of the stroke range, the restriction member When the output shaft is positioned at both ends of the stroke range by the rotational drive of the input shaft, the rotational drive of the input shaft from the neutral state is performed. A self-locking clutch comprising: a slider member positioned at a rocking allowable position that allows rocking of the regulating member in a direction. An input shaft that is pivotally driven about a pivot axis;
An output shaft that is screwed to the input shaft and moves relative to the input shaft with a predetermined stroke, and rotates integrally with the input shaft at both ends of the stroke range;
The output shaft can be slidably engaged with the outer surface of the output shaft to follow the relative movement of the output shaft along the direction of the stroke, and can swing on the surface along the pivot axis to be engaged with and disengaged from the output shaft. A restrictive member,
Neutral return means for biasing the restricting member to a neutral state to be engaged with the output shaft;
When the output shaft is fixed to a stationary member and the output shaft is located at a position other than both ends of the stroke range, the regulating member is regulated to the neutral state, and the output shaft is moved within the stroke range by rotating the input shaft. A self-locking clutch provided with a slider member that allows the regulating member to swing from the neutral state to the rotational drive direction of the input shaft when positioned at both ends of the input shaft.   The self-locking clutch according to claim 1 or 2, wherein the neutral return means is a spring provided in the regulating member.

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