JP2002213490A - Actuator of clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the space and weight of an actuator, and reduce manufacturing cost, while satisfying the functions of the actuator. SOLUTION: This actuator 86 has a bar-shaped first member 10, a cylindrical second member 20, a motor 40, and a rod 30. The bar-shaped first member 10 has a first screw surface 12a. The cylindrical second member 20 has a second screw surface 20a, and is supported nonrotatably by a casing 50. This second screw surface 20a meshes with the first screw surface 12a. The motor 40 makes the bar-shaped first member 10 rotate. The rod 30 moves, so as to connect and disconnect a clutch by making it interlock with the movement of the cylindrical second member 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator for a clutch, and more particularly to an actuator for converting a rotational force of a rotary drive unit into a linear motion.

[0002]

2. Description of the Related Art Generally, a clutch is used for interrupting a driving force in a vehicle or the like. The clutch usually includes a clutch disk assembly, a clutch cover assembly, and a clutch release mechanism.

[0003] The clutch disk assembly includes a friction coupling portion disposed opposite the flywheel on the engine side, a plate fixed to the friction coupling portion, and a spline elastically connected to the plate in a circumferential direction. And a hub. A main drive shaft extending from the transmission side is connected to the spline hub.

The clutch cover assembly includes a clutch cover connected to a flywheel, an annular pressure plate disposed in the clutch cover, and a diaphragm spring supported by the clutch cover and pressing the pressure plate toward the flywheel. have.

[0005] The clutch release mechanism has a release bearing engaged with the inner peripheral end of the diaphragm spring, and an actuator for moving the release bearing in the axial direction. Actuators include a type using hydraulic pressure, a mechanical type using a motor, and the like.

In such a clutch, when an operator operates, for example, a switch or a lever at hand, an actuator moves a release bearing to release the pressure of the pressure plate by the diaphragm spring. This disengages the clutch, but when connecting the clutch, the release bearing is moved in the opposite direction, and the pressure plate is pressed by the diaphragm spring. As a result, the friction coupling portion is sandwiched between the flywheel and the pressure plate, and the clutch is connected.

[0007]

The mechanical type actuator used for the above-mentioned clutch is shown in FIGS.
As shown in FIG. 4 is a side view of the actuator, FIG. 5 is a longitudinal sectional view of the actuator when the rod 107 is pushed out, and FIG. 6 is a longitudinal sectional view of the actuator when the rod 107 is retracted. This actuator converts the rotational force of the motor 101 into a linear movement of the rod 107, and moves the release bearing of the clutch in the axial direction by the movement of the rod 107. The movement of the rod 107 is transmitted to the release bearing via a swing member that swings about a fulcrum.

In this actuator, the rotation of the motor 101 causes the stopper plate 104 to rotate about the pin 103, and accordingly the rod 107 moves in the front-rear direction (left-right direction in the drawing). The stopper plate 104
The outer peripheral portion has a sector gear 105 meshing with a gear mounted on the rotation shaft of the motor 101. Rod 107
Is mounted with a rubber boot 108 and is supported by the casing 102 so as to be able to move back and forth.

Although such a conventional mechanical actuator generally satisfies the functions, it has a relatively large number of components and a large number of components.
It is difficult to reduce manufacturing costs. In addition, if the stroke amount of the rod 107 is to be increased, the actuator becomes considerably large.

An object of the present invention is to reduce the space and weight of an actuator while satisfying the function of the actuator.
The aim is to reduce manufacturing costs. In contrast to the above-mentioned clutch using a pressing force of a diaphragm spring or the like, the present applicant discloses in Japanese Patent Application Laid-Open No. 8-303483 that the pressure load when the pressure plate presses the frictional connection portion against the flywheel. A clutch operating mechanism with improved controllability is disclosed. Here, instead of the diaphragm spring, an annular lever plate whose outer peripheral end is supported by the clutch cover and whose intermediate portion contacts the pressure plate is provided. And
By pressing the release bearing, which comes into contact with the inner peripheral end of the annular lever plate, with an actuator, a pressing force required for clutch connection is generated. With this configuration, the pressing force applied to the pressure plate can be controlled only by the stroke amount of the release bearing by the actuator without considering the spring characteristics of the diaphragm spring. Can be done relatively easily.

On the other hand, in the case of such a clutch, a reaction force acts on an actuator for moving the release bearing toward the flywheel when the clutch is connected. Therefore, it is difficult to apply an actuator to this type of clutch unless there is a lock mechanism for the reaction force. However, when a lock mechanism is separately provided, a space-related disadvantage occurs and the manufacturing cost increases.

Another object of the present invention is to provide an actuator in which self-locking is performed with respect to a reaction force from a clutch bearing without separately providing a lock mechanism.

[0013]

According to a first aspect of the present invention, there is provided a clutch actuator including a first member, a second member, a rotation drive unit, and a clutch control member. The first member has a first screw surface. The second member has a second screw surface and is non-rotatably supported. This second screw surface meshes with the first screw surface. The rotation driving means rotates the first member. The clutch control member moves so as to connect / disconnect the clutch in conjunction with the movement of the second member.

Here, when the rotation driving means rotates the first member, the second member moves because the two screw surfaces are in mesh with each other and the second member cannot be rotated. In accordance with the movement of the second member, the clutch control member moves so as to connect / disconnect the clutch.

As described above, since the rotation of the first member is converted into the movement of the second member by utilizing the engagement of the first and second members, the space is required as complicated as the conventional one. The function of the actuator can be satisfied without employing a structure. The number of components can be reduced, and the cost advantage is high. On the other hand, if there is a space equivalent to that of the conventional actuator, the movement amount (stroke amount) of the clutch control member can be made larger than that of the conventional actuator.

Further, as compared with the conventional structure, it is easier to make the amount of rotation by the rotation driving means and the amount of movement of the clutch control member proportional, so that clutch control becomes easier.

According to a second aspect of the present invention, there is provided the clutch actuator according to the first aspect, further comprising a speed reduction device. The speed reducer is disposed between the first member and the rotation driving means.

Here, by using a speed reduction device, the first
Since the rotation speed of the member can be reduced, the movement speed of the second member and the clutch control member can be reduced to a desired value. It should be noted that it is desirable to use a speed reduction device in order to make the desired rotation speed of the first member correspond to the range of the controllable rotation speed even when the rotation drive means that can control the rotation speed is used.

The clutch actuator according to claim 3 is the actuator according to claim 1 or 2,
A swing member is further provided. The swing member swings about a fulcrum, and causes the clutch control member and the clutch to interlock. Further, the clutch control member is engaged with the swing member via a circumferential surface or a spherical surface.

Here, the movement of the clutch control member is transmitted to the clutch by the swing member. Therefore, the swing of the swing member may cause a force to act in a direction other than the moving direction of the clutch control member at an engagement portion between the clutch control member and the swing member. However, in this case, since the clutch control member is engaged with the swinging member via the circumferential surface or the spherical surface, the adverse effect of the force acting in a direction other than the moving direction of the clutch control member is suppressed.

A clutch actuator according to a fourth aspect is the actuator according to any one of the first to third aspects, wherein the lead angles of the thread grooves on the first screw surface and the second screw surface are such that the rotation driving means is The first member and the second member are determined based on the coefficient of friction between the first screw surface and the second screw surface so that the first member and the second member do not relatively move due to the force from the clutch control member when not operating.

Here, even if a force from the clutch acts on the clutch control member when the rotation driving means is not operating, the first member and the second member do not move relative to each other, and the state in which the self-lock is applied. Become. Therefore, in the actuator according to the present invention, it is not necessary to provide another member or another mechanism for achieving self-lock.

According to a fifth aspect of the present invention, there is provided the actuator according to the fourth aspect, wherein a friction coefficient between the first screw surface and the second screw surface is in a range of 0.10 to 0.25; The lead angles of the thread grooves on the first screw surface and the second screw surface are in the range of 5.7 ° to 14.0 °.

The friction coefficient (μ) and the lead angle (θ) are in a relationship of tan (θ) <(μ), and the material of the first and second screw surfaces, the surface roughness, and the lubricant It depends on how you choose. In the ordinary technology, the settable range of the friction coefficient (μ) is generally in the range of 0.10 to 0.25, and thus the numerical value is set as described above.

It is desirable to actively control the friction coefficient (μ) in accordance with the selection of the material used for the first member and the second member. The clutch actuator according to a sixth aspect is the actuator according to any one of the first to fifth aspects, wherein the actuator is applied to a clutch that receives a necessary pressing force only from the clutch control member when the clutch is connected.

Here, since the pressing force of the clutch is determined only by the force exerted on the clutch by the clutch control member, it is easy to make the amount of rotation by the rotation driving means and the amount of movement of the clutch control member proportional. The advantage of applying the actuator of the present invention to a clutch is great.

[0027]

1 and 2 show a clutch actuator according to an embodiment of the present invention. The actuator 86 shown here is connected to a clutch 80 (FIG.
), And is a mechanical actuator that uses the motor 40 as a drive source.

<Structure of Actuator 86> The actuator 86 mainly includes a first rod-shaped member 10 and a second cylindrical member.
A member 20, a rod (clutch control member) 30, a motor (rotation drive unit) 40, a casing 50, and a reduction gear 60 are provided.

The first rod-shaped member 10 comprises a supported part 11 rotatably supported by a shaft support 53 of a casing 50 and a rod-shaped screw part 12. The outer peripheral surface of the rod-shaped screw portion 12 is a first screw surface 12a in which a screw groove is formed.

The cylindrical second member 20 is arranged on the inner peripheral side of the cylindrical portion 51 of the casing 50 and engages with the cylindrical portion 51 so as to be slidable and non-rotatable. The inner peripheral surface of the cylindrical second member 20 is a second screw surface 20 a in which a thread groove is formed, and meshes with the first screw surface 12 a of the rod-shaped first member 10.

The first screw surface 12a and the second screw surface 2
The lead angle and friction coefficient of the thread groove of 0a will be described later. The motor 40 is fixed outside the casing 50. The rotating shaft 41 of the motor 40 has its tip supported by the shaft support 52 of the casing 50.

The speed reducer 60 includes a rotating shaft 41 of the motor 40.
, And a large gear 62 fixed to the supported portion 11 of the rod-shaped first member 10.
The speed reducer 60 transmits the rotation of the motor 40 to the first rod-shaped member 10 at a reduced speed.

The rod 30 is a rod body 31 fixed to the distal end (the right side in FIGS. 1 and 2) of the cylindrical second member 20.
And a rod tip ball 32 attached to the tip of the rod body 31. The rod tip ball 32 has a spherical surface 32a at a portion that contacts a swing member 85 described later. Further, an outer peripheral end of a bellows-like rubber boot 70 is fixed to a distal end of the tubular portion 51 of the casing 50. The rubber boot 70 has an inner peripheral end attached to the rod body 31 and serves to close the opening of the tubular portion 51.

<Operation of Actuator 86> The state shown in FIG. 1 is a state where the rod 30 is retracted. When the motor 40 is rotated forward in this state, the rotational force reduced by the reduction gear 60 is transmitted to the first rod-shaped member 10. When the rod-shaped first member 10 rotates, the cylindrical second member 20 meshing with the first member 10 is made unrotatable by the casing 50, so that the second screw surface 20a is pushed by the first screw surface 12a to move forward ( (Right side of FIG. 1). Along with this,
The rod 30 moves forward to the state shown in FIG.

On the other hand, in the state shown in FIG.
When 0 is rotated in the reverse direction, the first rod-shaped member 10 rotates in the reverse direction, and the second cylindrical member 20 and the rod 30 are returned to the rear. <Regarding the Clutch 80 Controlled by the Actuator 86> [Configuration] In the clutch 80 shown in FIG. 3, OO is the rotation axis. The clutch 80 is a device for transmitting and interrupting torque from a flywheel 98 on the engine side (left side in FIG. 3) to a main drive shaft 99 on the transmission side (right side in FIG. 3). The clutch 80 mainly includes a clutch disk assembly 81, a clutch cover assembly 82, and a clutch release mechanism 83. The outer periphery of the clutch 80 is covered with a clutch cover 82a.

The friction connecting portion 81a of the clutch disk assembly 81 is disposed between the pressure plate 82b of the clutch cover assembly 82 and the flywheel 98, and is held between the two at the time of clutch connection. .

The lever plate 82c of the clutch cover assembly 82 is an annular plate member having a center hole, and has a minimum rigidity as a lever. The lever plate 82c rotates integrally with the clutch cover 82a, and a transmission-side surface of the outer peripheral end is in contact with the clutch cover 82a. Also, the lever plate 82
An intermediate portion in the radial direction of c is in contact with the pressure plate 82b.

The clutch release mechanism 83 mainly includes
An annular release bearing 84, a swing member 85, and an actuator 86 are provided. The release bearing 84 has a lever plate 82 on the engine side.
c is in contact with the inner peripheral end from the transmission side.
The swinging member 85 is a member that swings around a rotation fulcrum 85a fixed as shown in FIG.
5b is a release bearing 8 from the transmission side.
4 abuts. Further, the other end 85c of the swing member 85
Has a hemispherical concave portion on the engine side, and the concave portion is engaged with the rod tip ball 32 of the actuator 86. Specifically, the portion of the spherical surface 32 a of the rod tip ball 32 is in contact with the concave portion of the other end 85 c of the swing member 85.

[Operation] When the clutch-connected driver operates, for example, a switch at hand, a signal is sent to the motor 40 of the actuator 86 and the rod 3
0 moves to the transmission side, and accordingly one end 85b of the swing member 85 pushes the release bearing 84 toward the engine. At this time, since the release bearing 84 applies a constant load to the inner peripheral end of the lever plate 82c,
The posture of the lever plate 82c changes. Here, a load several times the load from the release bearing 84 acts on the pressure plate 82b according to the lever ratio. As a result, the pressure plate 82b pushes the friction coupling portion 81a of the clutch disk assembly 81 toward the engine, and the friction coupling portion 81a and the flywheel 98 are frictionally engaged. As a result, the torque from the flywheel 98 is transmitted to the clutch disc assembly 81,
The power is output to the main drive shaft 99 connected to the spline hub 81b of the clutch disk assembly 81.

[0040] In the clutch connection state shown in the clutch disconnection Figure 3, when the driver operates the switch or the like at hand For example, the signal is sent to the motor 40 of the actuator 86, the rod 30 is moved toward the engine, the lever plate 82c No pressing load is applied to the pressure plate 82b from the pressure plate. At this time, the urging force of the strap plate connecting the outer peripheral portion of the clutch cover 82a and the outer peripheral portion of the pressure plate 82b causes the pressure plate 82b to move toward the transmission. As a result, the friction coupling portion 81a of the clutch disc assembly 81
Release and clutch disengage.

In the clutch operation described above, an elastic member (such as a coil spring or a diaphragm spring) is not used to apply a pressing load to the pressure plate 82b. That is, the pressing load applied from the lever plate 82c to the pressure plate 82b is determined only by the load applied from the release bearing 84 to the inner peripheral end of the lever plate 82c. That is, the clutch 80 has a configuration in which the pressing force necessary for connecting the clutch is supplied only by the actuator 86 via the swing member 85.

<First Screw Surface 12a of Actuator 86>
Regarding the Second Screw Surface 20a> The First Screw Surface 12a of the Bar-shaped First Member 10 and the Second Screw Surface 20 of the Cylindrical Second Member 20
In the case of a, the lead angle and friction coefficient of the thread groove are set in the following numerical ranges.

Lead angle of thread groove: 5.7 ° -1
4.0 ° Coefficient of friction between the first screw surface 12a and the second screw surface 20a:
0.10 to 0.25 By setting such a value, the reaction force from the clutch 80 when the motor 40 is not operating is not
Even if it acts on the rod 30 via 5, the rod-shaped first member 10 does not rotate and the cylindrical second member 20 does not move. That is, in the actuator 86 of the present embodiment, the first screw surface 1
The lead angle of the screw groove is set according to the friction coefficient of the second screw surface 20a.

The size of the lead angle of the thread groove is as follows.
This affects the feed speed at which the rod 30 is pushed out and the maximum reaction force at which the lock function can work. If one is given too much priority, the other will be sacrificed. Therefore, the lead angle is set so that the feed speed and the lock function are compatible, taking into account the expected clutch reaction force.

<Characteristics of Actuator 86 and Clutch 80 Controlled by It> (1) In the actuator 86, the engagement between the two threaded surfaces 12a, 20a of the first rod member 10 and the second cylindrical member 20 is utilized. The rotational force of the motor 40 is converted into a linear movement of the rod 30. For this reason, without employing a complicated and space-consuming structure as shown in FIGS.
The function as an actuator can be satisfied. Compared to a conventional actuator, the number of components is reduced, and the manufacturing cost is also reduced.

The stroke of the rod 30 is larger than that of the conventional actuator, even though the actuator 86 fits in the same space as the conventional one.
Further, since the amount of rotation of the rotating shaft of the motor 40 and the amount of movement of the rod 30 are in a proportional relationship, clutch control can be easily performed.

(2) In the clutch 80, the movement of the rod 30 is transmitted to the release bearing 84 of the clutch 80 by the swing member 85. Therefore, when the swing member 85 swings, a force may be exerted in a direction other than the moving direction of the rod 30 at the engagement portion between the rod 30 and the swing member 85. However, here, the rod tip ball 32 is provided at the tip of the rod 30, and the spherical surface 32a is brought into contact with the concave portion of the other end 85c of the swinging member 85 (see FIG. 3). Radial force is reduced. Accordingly, the radial force acting on the meshing portion between the first rod-shaped member 10 and the second cylindrical member 20 is also reduced, and the adverse effect on the actuator 86 is suppressed.

(3) In the actuator 86, the motor 4
Even when the reaction force from the clutch 80 acts on the rod 30 when the 0 is not operating, the self-lock is applied by the friction between the first screw surface 12a and the second screw surface 20a,
The cylindrical second member 20 does not return. As described above, in the actuator 86, the lead angle of the screw groove is appropriately adjusted according to the friction coefficient of the first screw surface 12a and the second screw surface 20a without providing another member or another mechanism for achieving the self-locking function. By setting to, a self-lock function is provided.

[0049]

According to the present invention, since the rotation of the first member is converted into the movement of the second member by utilizing the engagement of the first and second members, the number of components is reduced, and the space is saved. And cost reduction. Also, if there is a space equivalent to that of the conventional actuator, the stroke amount of the clutch control member can be made larger than that of the conventional actuator.

According to another aspect of the present invention, since the lead angle of the thread groove is appropriately set, even if a force from the clutch acts on the clutch control member when the rotation driving means is not operating, the first angle can be obtained. The first member and the second member do not move relative to each other, and are in a self-locked state. Therefore, there is no need to provide another member or another mechanism for achieving self-locking.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of an actuator according to an embodiment of the present invention (when a rod is retracted).

FIG. 2 is a partial cross-sectional view of the actuator according to the embodiment of the present invention as viewed from a side (when the rod is pushed out).

FIG. 3 is a partial cross-sectional side view of the clutch.

FIG. 4 is a side view of a conventional actuator.

FIG. 5 is a longitudinal sectional view of a conventional actuator (when a rod is pushed out).

FIG. 6 is a longitudinal sectional view of the conventional actuator (when the rod is retracted).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rod-shaped 1st member (1st member) 12 Rod-shaped screw part 12a 1st screw surface 20 Cylindrical 2nd member (2nd member) 20a 2nd screw surface 30 Rod (clutch control member) 32 Rod tip ball 32a Spherical surface 40 Motor (rotation driving means) 60 Reduction gear 80 Clutch 85 Swinging member 85a Rotation fulcrum (fulcrum) 86 Actuator

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J056 AA33 AA37 AA44 AA58 AA62 BA04 BE06 CD04 GA02 GA12 3J062 AA01 AB01 AB21 AC07 AC08 BA12 CD02 CD22

Claims (6)

[Claims] 1. A first member having a first screw surface, a second member having a second screw surface meshing with the first screw surface and supported non-rotatably, and rotating the first member. An actuator for a clutch, comprising: a rotation drive unit; and a clutch control member that moves so as to connect / disconnect the clutch in conjunction with the movement of the second member. 2. The clutch actuator according to claim 1, further comprising a speed reducer disposed between said first member and said rotary drive means. And a swing member for swinging about a fulcrum and interlocking the clutch control member and the clutch, wherein the clutch control member is connected to the clutch control member via a circumferential surface or a spherical surface. 3. The method according to claim 1, wherein the swing member is engaged with the swing member.
The clutch actuator according to claim 1. 4. A lead angle of a thread groove of the first screw surface and the second screw surface, wherein the first member and the second member are rotated by a force from the clutch control member when the rotation driving means is not operated. The clutch actuator according to any one of claims 1 to 3, wherein the clutch member is determined based on a friction coefficient between the first screw surface and the second screw surface so that the two members do not relatively move. 5. A lead angle of a thread groove between the first screw surface and the second screw surface, wherein a coefficient of friction between the first screw surface and the second screw surface is in a range of 0.10 to 0.25. Is in the range of 5.7 ° to 14.0 °.
The clutch actuator according to claim 1. 6. The clutch actuator according to claim 1, wherein said clutch actuator is applied to a clutch which receives a necessary pressing force only when said clutch is connected from said clutch control member.