JPH05256359A - Electric actuator with maintenance function - Google Patents

Abstract

PURPOSE:To reduce an electric power to be consumed extremely by requiring an electric power for driving only during exerting an electric actuator. CONSTITUTION:An electric actuator 50 with a maintanance function is composed of a rotary shaft 53 supported rotatably to a housing 8, an electric motor 51 for rotating and driving this rotary shaft by receiving an electric power/for driving, a ball screw converting the rotary motion of the rotary shaft 53 to an axial direction motion, a slider 55 being installed on the rotary shaft 53 through the ball screw and moved in the axial direction in response to the rotation of the rotary shaft, a friction clutch being connected to this slider 55 and exerted by receiving the axial direction motion and an electro-magnetic brake 60 fixing and maintaining the rotary shaft by using the electric power/for driving. The electro-magnetic brake 60 can fix and maintain the rotary shaft 53 in non-electricity transmission and release the maintenance of the rotary shaft 53 by transmitting electricity and driving.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric actuator used for controlling engagement / disengagement of a friction clutch of a transmission.

[0002]

2. Description of the Related Art Conventionally, engagement / disengagement control of a friction clutch of a transmission has been performed by operating a clutch pedal or by using hydraulic pressure. Those operated by operating the clutch pedal are mainly used in a manual transmission, and those operated by hydraulic pressure are generally used in an automatic transmission. However, recently, an automatic transmission in which a clutch pedal operation and a speed change lever operation in a manual transmission are automatically performed by using hydraulic pressure and the like are being put into practical use. Therefore, the structure of this automatic transmission is the same as that of a conventional manual transmission, and a mechanism for automatically performing a clutch operation and a gear shifting operation is added to the structure.

By the way, in such a conventional automatic transmission, clutch operation control is generally performed by using hydraulic pressure, but recently, electric power is used instead of hydraulic pressure by an electric actuator. It has also been proposed to perform engagement / disengagement control of the friction clutch. For example, JP-A-63
Japanese Patent Laid-Open No. 203958 discloses an electric actuator that converts a rotational torque of an electric motor into a thrust force by a ball screw mechanism and controls engagement and disengagement of a friction clutch by the thrust force. The friction clutch is provided with a spring for urging the friction clutch toward the release side, and the friction clutch is normally in the released state. When the rotational torque of the electric motor is converted into a thrust force by the ball screw mechanism and transmitted to the friction clutch, the friction clutch receives the thrust force and is engaged.

Further, in Japanese Patent Laid-Open No. 2-180375, in such an electric actuator for engagement / disengagement control of a friction clutch, an electromagnetic brake for fixing and holding a rotating shaft of an electric motor at a predetermined position is provided and friction with the electromagnetic brake is provided. An electric actuator in which an elastic member is arranged between the clutch and the clutch has been proposed. In order to rotate the electric motor and hold the friction clutch in the engaged state, it is necessary to drive the electric motor during that time, and a large amount of electric power is required to drive the electric motor. For this reason, in this electric actuator, the rotating shaft of the electric motor is fixedly held by the electromagnetic brake in a state where the friction clutch is engaged, so that the driving power of the electric motor is reduced. However, since there is a problem that the engaging force of the friction clutch decreases due to a slight backlash of the coupling system and the like only by holding by the electromagnetic brake, an elastic member is provided between the electromagnetic brace and the friction clutch. The engaging force of the friction clutch is maintained by the elastic deformation force of.

[0005]

However, in the case of the electric actuator having the above-mentioned structure, the driving power of the electric motor can be reduced by fixing and holding the rotary shaft by the electromagnetic brake, but during that time. There is a problem that it is necessary to supply drive power to the electromagnetic brake, and power for driving the electromagnetic brake is required.

The present invention has been made in view of these problems.
It is an object of the present invention to provide an electric actuator having a configuration that requires driving power only while operating the electric actuator and can significantly reduce power consumption.

[0007]

In order to achieve such an object, according to the present invention, a rotary shaft rotatably supported by a housing, and an electric means for driving the rotary shaft by receiving driving power. An electric actuator with a holding function is constituted by a motion converting means for converting the rotational motion of the rotary shaft into an axial motion and an electric power braking means for fixing and holding the rotary shaft by using driving power, and an axial motion in the motion converting means. The friction clutch is connected to the portion that performs the operation, and the friction clutch is engaged and operated by receiving this axial movement.The power braking means holds the rotating shaft fixed when it is not energized and is energized and driven. In this configuration, the holding of the rotating shaft is released.

The motion converting means is composed of a male screw formed on the rotary shaft and a slider provided on the rotary shaft and having a female screw screwed to the male screw. The slider may be configured to move in the axial direction on the rotation axis according to the rotation. Further, it is preferable that the electric power braking means is an electromagnetic brake of a braking type when not energized, and the braking operation is performed by spring force when deenergized, and the braking force is released by electromagnetic force when energized. Furthermore, as the friction clutch, a friction clutch of a type that is engaged by the urging force of a built-in spring is used, and a slider is connected to the release member of this friction clutch means via a release fork, and the slider is axially moved to form the release member. The frictional clutch is preferably configured to be released by the applied pressing force.

[0009]

When the electric actuator with a holding function having the above-mentioned structure is used, when a driving power is supplied to the electric means (for example, an electric motor) to rotationally drive the rotary shaft, the rotary motion of the rotary shaft is moved in the axial direction by the motion converting means. Is converted to. The axial movement is transmitted to the friction clutch connected to the portion of the movement converting means that performs the axial movement, and the thrust force associated with the axial movement acts on the friction clutch to control the engagement of the friction clutch. In this electric actuator, since the rotating shaft is fixedly held by the electric braking means, when the rotating shaft is rotationally driven by the electric means as described above, driving power is also supplied to the electric braking means. The holding of the rotary shaft by this is released, and the rotary shaft is made rotatable.

When the friction clutch is actuated from the engaged state to the released state by the electric actuator as described above, the drive power supply to the electric power braking means is cut off and the electric power braking means holds the rotary shaft fixedly. The drive power supply to the means is also cut off. In this way, the friction clutch is held in the released state, and it is not necessary to supply drive power to the electric actuator while this state continues. That is,
In the case of this electric actuator, the drive power is required only when the friction clutch is operated, specifically, when the engagement / disengagement state of the friction clutch is changed, and the drive power is not supplied while the engagement / disengagement state is maintained. It is unnecessary. Here, the time to change the engagement / disengagement state of the friction clutch (clutch operation time)
Is extremely short compared to the time for maintaining the engaged / disengaged state (the time for maintaining the clutch in the engaged state, the half-clutched state, or the released state). Therefore, in the case of the present invention, the power consumption of the electric actuator is very small.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. In the figure, the arrow U indicates the upper side and the arrow R indicates the right side. The electric actuator with a holding function according to the present invention is used for controlling the operation of a main clutch (a clutch that connects and disconnects the engine output shaft and the transmission input shaft) in an automatic transmission having the same structure as a conventional manual transmission. ..

A schematic structure of a power transmission system of the automatic transmission AT is shown in FIG. The automatic transmission AT is a main clutch MC mounted on the flywheel W of the engine E.
The main clutch MC is operated and controlled by the electric actuator with a holding function according to the present invention.

As shown in detail in FIG. 1, the main clutch MC is a cover 1 attached to a flywheel W.
And the friction disk 3 located between the pressure plate 4 and the flywheel W in the cover 1.
And a diaphragm spring 2 supported by the cover 1 and pressing the pressure plate 4 toward the friction disc 3. Normally diaphragm spring 2
The friction disc 3 is sandwiched between the flyhole W and the pressure plate 4 by the pressing force of, and the friction disc 3 is rotated integrally with the output shaft ES of the engine E. The inner diameter hub 3a of the friction disc 3 is spline-coupled to the main shaft 10 of the automatic transmission AT. In this state, the main shaft 10 and the engine output shaft ES are connected via the friction disc 3.

A release bearing 6 can come into lateral contact with the inner peripheral end of the diaphragm spring 5, and the release fork 7 is attached to the release bearing 6.
One end 7a of the abuts from the side. The release fork 7 is swingably supported by the transmission housing 8 at the intermediate portion 7a, and the other end 7c is connected to the slider 55 of the electric actuator 50.

When the slider 55 of the electric actuator 50 is moved to the right, the other end 7c of the release fork 7 connected thereto is also moved to the right, and the release fork 7 swings clockwise around the intermediate portion 7a. To be done.
Due to this swing, the release bearing 6 is pushed to the left by being pushed by the one end 7a, pushes the inner peripheral end of the diaphragm spring 5 to the left, and the pressing of the fresher plate 4 is released. As a result, the friction disc 3 becomes free, the connection between the engine output shaft ES and the main shaft 10 is released, and the main clutch MC is turned off (disengaged). Conversely, if the slider 55 is moved to the left,
The action opposite to the above is performed, and the main clutch MC is in the on (contact) state.

As shown in detail in FIG. 3, the electric actuator 50 is connected to an electric motor 51 mounted on the transmission housing 8 and a shaft 51a of the electric motor 51 by a coupling 52 so as to extend coaxially. Rotating shaft 5 rotatably supported by housing 8
3 and the shaft 51 of the electric motor 51 operated by the electromagnetic force.
and an electromagnetic brake 60 capable of fixing and holding a. A ball screw 53a is formed on the rotary shaft 53, and a slider 55 is mounted on the rotary shaft 53 by being screwed with the ball screw 53a. Therefore, when the rotating shaft 53 is rotated by the electric motor 51, the slider 55 is moved left and right on the rotating shaft 53 by the ball screw action. That is, the ball screw mechanism causes the rotary motion of the rotary shaft 53 to move to the slider 55.
Is converted into an axial motion of.

The other end 7c of the release fork 7 is inserted into the engaging groove 55a of the slider 55 and the other end 7c is locked to the slider 55. Therefore, the slider 55 is axially moved in the above-described manner. When it is moved to, the release fork 7 is swung, and engagement / disengagement control of the main clutch MC is performed. The sensor shaft 5 of the stroke sensor 58 is connected to the slider 55 via a connecting plate 56.
8a is connected, and the axial position of the slider 55 is detected by the stroke sensor 58.

The electromagnetic brake 60 includes a body 61 fixed in the housing 8, an electromagnetic coil 62 disposed in the body 61, a compression spring 63 also disposed in the body 61, and a body 61. Is arranged to face the side of
The brake disc 65 is arranged between the pressure plate 64 and the end plate 66. The brake disc 65 is connected to a hub 67 that is key-connected to the shaft 51a of the electric motor 51, and when the electromagnetic coil 62 is not energized, the compression plate 63 biases the pressure plate 64 and the end plate 66. Sandwiched between. Therefore, when the electromagnetic coil 62 is not energized,
The brake disc 65 is fixedly held and the electric motor 51
The shaft 51a is fixedly held.

When the electromagnetic coil 62 is energized, the electromagnetic force generated in the coil 62 causes the bleeder plate 6 to move.
4 is moved left against the bias of the compression spring 63. As a result, the clamping of the brake disc 65 by the pressure plate 64 and the end plate 66 is released, and the brake disc 65 becomes free. Therefore, the shaft 51a of the electric motor 51 is also in a freely rotatable state.

This electromagnetic brake 60 includes an electric motor 51.
Thus, when the rotating shaft 53 is rotated to change the engagement / disengagement state of the main clutch MC, electricity is supplied to bring the rotating shaft 53 into a free state. On the other hand, when the main clutch MC is held in the disengaged state, for example, when the main clutch MC is held in the on (contact) state, the off (disengaged) state or the half-clutch state, the electromagnetic brake 60 is de-energized and rotated. The shaft 53 is fixedly held. At this time, the power supply to the electric motor 51 is turned off to save power.

On the other hand, the main shaft 10 of the transmission
As shown in FIG. 2, the first speed drive gear 1
1, reverse drive gear 16, second speed drive gear 12, third
A high speed drive gear 13, a fourth speed drive gear 14, and a fifth speed drive gear 15 are arranged. Here, the first speed drive gear 1
1, a reverse drive gear 16 and a second speed drive gear 12 are arranged so as to be coupled to the main shaft 10, and a third speed drive gear 13, a fourth speed drive gear 14 and a fifth speed drive gear 1 are provided.
5 is rotatably arranged on the main shaft 10.

A counter shaft 20 extending in parallel with the main shaft 10 is rotatably disposed below the main shaft 10. The counter shaft 20 includes an output gear 26, a first speed driven gear 21, a reverse driven gear 26, a second speed driven gear 22, a third speed driven gear 23, in this order from the left.
A fourth speed driven gear 24 and a fifth speed driven gear 25 are arranged. Here, the output gear 26 and the third speed driven gear 2
The third, fourth speed driven gear 24 and fifth speed driven gear 25 are arranged to be coupled to the counter shaft 20, and the first speed driven gear 21 and second speed driven gear 22 are rotatably arranged on the counter shaft 20. Has been done. The reverse driven gear 26 is coupled to the counter shaft 20 via the third hub 29.

First speed drive gear 11 and second speed drive gear 1
The second, third speed drive gear 13, fourth speed drive gear 14 and fifth speed drive gear 15 are respectively a first speed driven gear 21, a second speed driven gear 22, a third speed driven gear 23 and a fourth speed driven gear. Is constantly meshed with the gear 24 and the fifth speed driven gear 25,
The first to fifth speed power transmission paths are formed by the gear trains meshing with each other.

A first hub 27 is mounted between the third speed drive gear 13 and the fourth speed drive gear 14 on the main shaft 10, and is opposed to the first hub 27 from the left and right sides to the third speed clutch gear 13a and the fourth speed gear. A clutch gear 14a is provided. Therefore, by moving the first sleeve 27a mounted on the first hub 27 so as to be movable in the axial direction to the left and right, the sleeve 27a is moved to the both clutch gears 1a and 1b.
The third speed drive gear 1 is engaged with one of 3a and 14a.
The third or fourth speed drive gear 14 can be connected to the main shaft 10. Although not shown, a synchronizing mechanism is arranged at the portions of both clutch gears 13a and 14a.

A second hub 28 having a second sleeve 28a is arranged on the right side of the fifth speed drive gear 15, and the second sleeve 28a is moved leftward to move the fifth speed clutch gear 15 to the left.
The fifth speed drive gear 15 can be connected to the main shaft 10 by meshing with a. A synchronization mechanism is also arranged on the fifth side clutch gear 15a.

Similarly, a third hub 29 having a third sleeve 29a is mounted between the first speed driven gear 21 and the second speed driven gear 22 on the counter shaft 20. Move this third sleeve 29a left and right,
By engaging the first speed clutch gear 21a or the second speed clutch gear 22a with the third sleeve 29a, the first speed driven gear 21 or the second speed driven gear 22 can be coupled to the counter shaft 20.

A reverse shaft 17 is fixedly provided in parallel with the main shaft 10, and a reverse idler gear 18 is disposed on the reverse shaft 17 so as to be rotatable and movable left and right. The reverse idler gear 18 meshes with the reverse drive and driven gears 16 and 26 by moving leftward from the illustrated state, and a reverse power transmission path is formed by these gear trains.

In the transmission having the above construction, the first to third transmissions are provided.
By selectively moving the sleeves 27a, 28a, 29a and the reverse idler gear 18 in the axial direction,
It is possible to select one of the first to fifth speed power transmission paths and the reverse power transmission path to shift gears. This gear shifting operation is similar to that of the conventional manual transmission.
The shift forks engaged with the third sleeves 27a, 28a, 29a and the reverse idler gear 18 are moved in the axial direction.

However, in the manual transmission, this gear shifting operation is performed by manually operating the shift lever, but in this automatic transmission AT, as shown in FIG. 4, a shift operating motor 31 and a select operating motor 32 are provided. Has
Both of these motors 31 and 32 are used to perform an operation similar to the conventional manual operation. During this gear shift operation, the operation of the main clutch MC is also performed. The engagement / disengagement control of the main clutch MC is performed even when the main clutch MC starts or stops.

A control device for performing such shift control, start and stop control will be described with reference to FIG. This control is performed by controlling the operation of the electric motor 51 of the electric actuator 50, the electromagnetic brake 60, the shift operating motor 31, the select operating motor 32, and the throttle actuator 33 by a control signal sent from the controller CU. The controller CU includes an operation position signal S1 of the shift operation motor 31 and a selection operation motor 3
2 operating position signal S2 and main shaft rotation sensor 4
1 from the main shaft rotation speed signal Nm, the counter shaft rotation speed sensor 42 from the counter shaft rotation speed signal Nc, the throttle opening sensor 43 from the throttle opening signal θth, and the engine rotation sensor 44 from the engine rotation signal Ne. Then, the accelerator opening signal θac from the accelerator opening sensor 45 and the main clutch engagement / disengagement position signal Clp from the stroke sensor 58 are input.

In the controller CU, based on these input signals, the electric motor 51 and the electromagnetic brake 6
0 operation is controlled to control the operation of the main clutch MC, and the shift operation motor 31 and the selection operation motor 3 are controlled.
The gear shift control is performed by controlling the operation of No. 2.

Next, the operation control of the main clutch MC by the electric actuator 50 of the present invention will be described in detail. This operation control is performed according to the flow shown in FIGS. In this control, first, it is determined whether or not it is in an operating state (step S1). This judgment is made by judging whether the engine speed Ne is equal to or higher than idling speed. If it is not in the operating state, the control is not performed as it is.

If it is in the operating state, the process proceeds to step S2, and the clutch engagement / disengagement mode is determined. The clutch engagement / disengagement mode includes a mode (MODE = 1) in which the main clutch MC is turned off (disengaged) and a main clutch MC.
Is in a half-clutch state (MODE = 2) and the main clutch MC is in an on (contact) state (MO).
DE = 3). Which mode is required is determined based on the signal input to the controller CU.

For example, the vehicle speed V = 0 calculated from the counter shaft speed Nc (that is, the vehicle is in a stopped state), and MODE = 1 when the brake is operated or when gear shifting is required. Therefore, the control of step S10 is performed. In this control, first, the mode flag F (M = 1) is turned on (step S1).
1) Whether or not the electric motor 51 and the electromagnetic brake 60 are in an operable state, that is, whether or not they have a defect such as disconnection and whether or not they are in use are checked ( Step S12). And
The electromagnetic coil 62 of the electromagnetic brake 60 is energized (step S13), and the restriction of the rotational movement of the rotary shaft 53 is released.

In this manner, the electric motor 51 is energized to drive the slider 5 while the rotary shaft 53 is rotatable.
The rotary shaft for moving 5 to the right is driven (step S14). As a result, the inner peripheral end of the diaphragm spring 2 is pushed to the left, and the main clutch MC shifts to the off state. At this time, in step S15, the engagement / disengagement state of the main clutch MC is determined from the position signal of the slider 55 detected by the stroke sensor 58, and when it is completely turned off (disengaged), the electromagnetic brake 60 is first de-energized. As a result, the rotary shaft 53 is fixedly held, and the main clutch MC is held in the off state (step S16). And after a certain time delay from this,
The electric motor 51 is de-energized (step S17), and the mode flag F (M = 1) is turned off (step S1).
8).

In this way, the engagement / disengagement control of the main clutch MC in the mode where MODE = 1 is performed. As can be seen from the above control, while the main clutch MC is switched from the on state to the off state (the engagement state). The electric motor 51 and the electromagnetic brake 60 are only energized during the change of the released state. Then, when the main clutch MC is turned off, the electromagnetic brake 60 is de-energized, the rotating shaft 53 is fixed, and the main clutch MC is held in the off state. Therefore, there is no problem even if the electric motor 51 is de-energized, and the electric motor 51 and the electromagnetic brake 6
Both 0s are turned off, and the power consumption is significantly reduced.

On the other hand, when the vehicle speed V is low, the accelerator pedal is depressed, and the shift speed is other than neutral (for example, the first speed or the second speed), that is, when the vehicle is about to start. Is MODE = 2
Therefore, the control of step S20 is performed.
This control is similar to the control in step S10. First, the mode flag F (M = 2) is turned on (step S21),
After checking whether the electric motor 51 and the electromagnetic brake 60 are in an operable state (step S2
2) Then, the electromagnetic coil 62 of the electromagnetic brake 60 is energized (step S23) to release the restriction of the rotational movement of the rotary shaft 53. Next, the electric motor 51 is energized to drive the rotary shaft that moves the slider 55 (step S2).
4) Then, the main clutch MC is shifted to the half-clutch state (step S25).

The determination as to whether or not the clutch is in the half-clutch state may be made based on the position signal of the slider 55 detected by the stroke sensor 58, but may be made based on the engine speed and the main shaft speed. .. And
When in the half-clutch state, the electromagnetic brake 60 is de-energized to hold the main clutch MC in this state (step S26), and the electric motor 51 is de-energized after a predetermined time delay from this (step S27). ,
The mode flag F (M = 1) is turned off (step S2
8). Even in this case, the electric motor 51 and the electromagnetic brake 60 are only energized and driven during the transition of the main clutch MC from the on or off state to the half-clutch state (while changing the engagement / disengagement state). Then, the electric motor 51 and the electromagnetic brake 6
Both 0s are turned off, and the power consumption is significantly reduced.

Further, when the vehicle speed V is a predetermined value or higher, the shift speed is other than neutral, the brake is not operated, that is, the vehicle is running, M
It is determined that ODE = 3, and the control of step S30 is performed. This control is also similar to the control in step S10,
First, the mode flag F (M = 3) is turned on (step S31), and it is checked whether or not the electric motor 51 and the electromagnetic brake 60 are in an operable state (step S32). The coil 62 is energized (step S33), and the restriction of the rotational movement of the rotary shaft 53 is released. Next, the electric motor 51 is energized to drive the rotary shaft that moves the slider 55 to the left (step S34), and the main clutch MC is turned on (contact).
The state is shifted to (step S35).

When it is determined from the position signal of the slider 55 detected by the stroke sensor 58 that the main clutch MC is in the on state, the electromagnetic brake 60 is de-energized and the main clutch MC is held in this state (step S36). After a predetermined time delay from this, the electric motor 51 is de-energized (step S37), and the mode flag F (M = 1) is turned off (step S38). Even in this case, while the main clutch MC is in the ON state (while the engagement / disengagement state is changed), the electric motor 51
And the electromagnetic brake 60 is only energized,
When turned on, both the electric motor 51 and the electromagnetic brake 60 are turned off, and the power consumption is significantly reduced.

[0041]

As described above, according to the present invention, when the driving power is supplied to the electric means (for example, the electric motor) to drive the rotary shaft to rotate, the rotational movement of the rotary shaft is caused by the motion converting means in the axial direction. The movement is converted into movement, and this axial movement is transmitted to the friction clutch connected to the portion that performs the axial movement in the movement converting means, and the thrust force associated with the axial movement acts on the friction clutch, and the operation of this friction clutch is It is controlled. Here, the rotary shaft is fixedly held by the electric power braking means, but when the rotary driving of the rotary shaft is performed by the electric means, the drive power is also supplied to the electric power braking means, whereby the rotary shaft is rotated. Is released, and the rotary shaft is made rotatable.

Therefore, in the case of this electric actuator, the drive power is required only when the engagement / disengagement state of the friction clutch is changed, and the drive power (electric means and power brake) is maintained while the engagement / disengagement state is maintained. Drive power) is not required. Here, the time for changing the engagement / disengagement state of the friction clutch (clutch operation time) is extremely shorter than the time for maintaining the engagement / disengagement state (the time for maintaining the clutch in the engaged state, the half-clutch state or the released state), In the case of the present invention, the power consumption of the electric actuator can be made extremely small.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an electric actuator and a main clutch actuated by the electric actuator according to the present invention.

FIG. 2 is a skeleton diagram showing a power transmission path configuration of an automatic transmission having the main clutch.

FIG. 3 is a cross-sectional view showing a structure of the electric actuator.

FIG. 4 is a schematic diagram showing a control device configuration of the automatic transmission.

FIG. 5 is a flowchart showing control of a main clutch by the control device.

FIG. 6 is a flowchart showing control of a main clutch by the control device.

FIG. 7 is a flowchart showing control of a main clutch by the control device.

FIG. 8 is a flowchart showing control of a main clutch by the control device.

[Explanation of symbols] 2 diaphragm spring 3 friction disc 7 release fork 10 main shaft 20 counter shaft 50 electric actuator 51 electric motor 53 rotating shaft 55 slider 60 electromagnetic brake

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasumichi Onuki, 1-4-1, Chuo, Wako, Saitama Prefecture, Honda R & D Co., Ltd. (72) Inventor, Takamichi Shimada, 1-1-4, Chuo, Wako, Saitama No. Stock Company Honda Technical Research Institute

Claims (4)

[Claims] 1. An electric actuator for controlling the operation of a friction clutch for performing intermittent control of power transmission in a power transmission device, comprising: a rotary shaft rotatably supported by a housing; The motor comprises: an electric driving means for rotationally driving; a motion converting means for converting the rotational motion of the rotary shaft into an axial motion; and an electric power braking means for fixing and holding the rotary shaft by using driving power. The friction clutch is coupled to a portion that performs an axial movement, and the friction clutch is engaged by receiving the axial movement. An electric actuator with a holding function, which is configured to be fixedly held. 2. The motion converting means comprises a male screw formed on the rotary shaft and a slider provided on the rotary shaft, the slider having a female screw screwed to the male screw. The holding function according to claim 1, wherein the slider is configured to move in the axial direction on the rotation shaft according to the rotation of the rotation shaft, and the friction clutch is connected to the slider. With electric actuator. 3. The electric power braking means is an electromagnetic brake which is operated by receiving an electromagnetic force, and the braking force in the electromagnetic brake is obtained by a spring force and is released by the electromagnetic force. The electric actuator with a holding function according to claim 1 or 2, characterized in that. 4. The friction clutch is a friction clutch of a type that is engaged by an urging force of a built-in spring, and a release member of the friction clutch is connected to the slider via a release fork to move the slider in an axial direction. The electric actuator with a holding function according to claim 2, wherein the friction clutch is released by a pressing force applied to the release member in accordance with the above.