JP2000283195A - Electric disc brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically adjust abrasion of a brake pad on a electric disc brake. SOLUTION: First and second ball screw mechanisms 11, 12, an electric motor 10 and a pad abrasion compensating mechanism 13 are provided on a caliper main body 3. Braking force is generated by converting rotation of a main rotor 14 by the electric motor 10 to linear motion by the first and second ball screw mechanisms 11, 12 and pressing brake pads 5, 6 on a disc rotor through a piston 21 and a click part 4. Abrasion of the brake pads 5, 6 is adjusted by transmitting only rotational displacement of the main rotor 14 exceeding a specified area (equivalent to abrasion amount of the brake pads 5, 6) to a piston 25 by a pin 29 of a rotary ring 28 of the pad abrasion compensating mechanism 13, a circular arc groove 26A of a limiter and a unidirectional clutch 25 and advancing the piston 21 by an adjusting screw A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric disc brake for generating a braking force by the rotation of an electric motor.

[0002]

2. Description of the Related Art A so-called "dry brake" in which a braking force is generated by the output of an electric motor without using a brake fluid as a braking device for a vehicle such as an automobile.
Devices are known.

[0003] As a dry brake device, for example, as disclosed in International Patent Publication No. 96/03301, the rotational motion of an electric motor is converted into forward and backward movement of a piston by a roller screw mechanism (screw transmission mechanism). There is an electric disc brake device in which a brake pad is pressed against a disc rotor to generate a braking force. This type of electric disc brake device is
The brake pedal depression force (or displacement amount) by the driver is detected by a sensor, and the controller controls the rotation of the electric motor according to the detection to obtain a desired braking force.

Further, in the above-described electric disc brake device, various sensors are used to detect the vehicle state such as the rotation speed of each wheel, the vehicle speed, the vehicle acceleration, the steering angle, the vehicle lateral acceleration, etc. By controlling the rotation of the electric motor based on these detections, boost control, antilock control, traction control, vehicle stabilization control, and the like can be relatively easily incorporated.

[0005] In the above-mentioned electric disc brake device, it is necessary to maintain a predetermined pad clearance between the disc rotor and the brake pad in order to prevent dragging during non-braking. Therefore, conventionally, when the brake is released, the brake pad comes into contact with and separates from the disk rotor, and the electric motor is rotated by a predetermined angle in the return direction from the braking position, which is a boundary between the brake pad and the disk rotor, so that the return amount of the brake pad is kept constant. This is controlled to keep the pad clearance constant at all times, regardless of brake pad wear.

As a mechanism for compensating wear of a brake pad, for example, Japanese Patent Application Laid-Open No. 50-108465 discloses that a ball ramp mechanism is operated via a brake wire by operating a brake lever to generate a thrust on a piston. In a mechanical brake for a motorcycle that presses a brake pad, a combination of an adjusting screw provided on a piston and a ratchet mechanism having a predetermined backlash is used.
There is disclosed an apparatus in which a ratchet mechanism is operated to cause the piston to follow an adjustment screw against wear of a brake pad exceeding a certain amount.

[0007]

However, in the above-mentioned conventional electric disc brake, a transmission mechanism for converting the rotational motion of the electric motor into the linear motion of the piston in order to make the piston follow the wear of the brake pad. It is necessary to set the stroke amount to be sufficiently large in consideration of the wear amount of the brake pad, and this is a restriction on the design of the transmission mechanism, which is a problem.

In the mechanical brake for a motorcycle provided with the brake pad wear compensating mechanism, the piston is advanced by a fixed amount by an adjusting screw each time the wear amount of the brake pad exceeds the backlash of the ratchet mechanism. Since the piston is made to follow the abrasion of the abrasion, there is a problem that the adjustment for the abrasion becomes stepwise and a fine adjustment cannot be performed.

The present invention has been made in view of the above points, and an electric disc capable of continuously adjusting and compensating wear of a brake pad without increasing a stroke amount of a transmission mechanism. The purpose is to provide a brake.

[0010]

In order to solve the above-mentioned problems, the invention of claim 1 converts the rotational movement of a rotor by an electric motor into a linear movement of a piston via a transmission mechanism, and moves the piston. In an electric disc brake device configured to generate a braking force by pressing a brake pad against a disc rotor, an adjusting screw is provided between the transmission mechanism and the piston, and between the adjusting screw and the rotor, A limiter that transmits only a rotational displacement exceeding a predetermined range of the rotor and a one-way clutch are provided, and when the rotational displacement during braking of the rotor exceeds a predetermined range,
A pad wear compensation mechanism is provided which transmits the rotational displacement at the time of braking release of the rotor to the adjustment screw via the one-way clutch to advance the piston toward the disk rotor. .

With this configuration, if the brake pad wears out and the rotational displacement of the rotor of the electric motor during braking exceeds a predetermined range, the rotational displacement beyond the predetermined range becomes one when the braking is released. The power is transmitted to the adjusting screw via the directional clutch, and the piston advances toward the disk rotor.

According to a second aspect of the present invention, the rotational movement of the rotor by the electric motor is converted into a linear movement of the piston via a transmission mechanism, and the movement of the piston presses the brake pad against the disk rotor to reduce the braking force. In the electric disc brake device, the adjusting screw is provided between the transmission mechanism and the piston, and only the rotational displacement of the rotor exceeding a predetermined range is transmitted between the adjusting screw and the rotor. A limiter, a friction transmitting means for transmitting a rotational force by frictional force, and a one-way clutch are provided, and when the rotational displacement during braking of the rotor exceeds a predetermined range, the rotational displacement of the rotor beyond the predetermined range is reduced. The piston is advanced to the disk rotor side by transmitting to the adjusting screw via the friction transmission mechanism and the one-way clutch. Characterized in that it comprises a head wear compensating mechanism.

With this configuration, when the brake pad wears out and the rotational displacement of the rotor of the electric motor during braking exceeds a predetermined range, the rotational displacement beyond the predetermined range is applied to the friction transmission mechanism and The force is transmitted to the adjustment screw via the one-way clutch, and the piston advances toward the disk rotor. At this time, when the piston is pressing the brake pad against the disk rotor, a large frictional force is generated in the adjusting screw, so that the friction transmitting mechanism slips and the adjusting screw does not rotate.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the electric disc brake 1 has a caliper body 3 disposed on one side (usually inside the vehicle body) of a disc rotor 2 that rotates with wheels. A claw portion 4 is provided to extend to the opposite side over the two. Brake pads 5 and 6 are provided on both sides of the disk rotor 2, that is, between the disk rotor 2 and the caliper body 3 and between the claw 4. The brake pads 5 and 6 are movably supported in the axial direction of the disk rotor 2 by a carrier (not shown) fixed to the vehicle body, and the caliper body 3 is supported by the carrier of the disk rotor 2 by the carrier. It is guided movably along the direction.

A substantially cylindrical housing 9 of the caliper body 3
An electric motor 10, a first ball screw mechanism 11 (transmission mechanism), a second ball screw mechanism 12 (transmission mechanism), and a pad wear compensation mechanism 13 are provided therein.
(Rotor) is rotatably supported by a ball bearing 15. A cover 16 is attached to the rear end of the housing 5.

The electric motor 10 includes a stator 17 fixed to the inner periphery of the housing 9 and a motor rotor 18 mounted on the outer periphery of the main rotor 14 so as to face the inner periphery of the stator 17.
So that the motor rotor 18, that is, the main rotor 14, can be rotated by a desired angle in response to a control signal (electric signal) from a controller (not shown), and can be rotated with a desired torque. Has become.

The first ball screw mechanism 11 includes a main rotor 14,
A substantially cylindrical inner body 19 which is inserted into the main rotor 14 and is supported movably in the axial direction with respect to the housing 9 and is fixed in the rotational direction, and a thread groove formed in the inner body 19. It is composed of a plurality of balls 20 (steel balls) loaded, and converts the rotational movement of the main rotor 14 into a linear movement of the inner body 19. The main rotor
The thread grooves of the inner body 19 and the inner body 19 form a left-hand thread. When the main rotor 14 rotates clockwise (clockwise as viewed from the right in FIG. 1, the same applies hereinafter), the inner body 19 is rotated as shown in FIG.
The brake pad 5 moves to the left in the middle and presses the brake pad 5 against the disk rotor 2 via a piston 21 (described later) mounted on the inner body 19.

The second ball screw mechanism 12 includes a main rotor
And a substantially cylindrical outer body 22 which is provided integrally with the claw portion 4, is externally fitted to the main rotor 14, is supported movably in the axial direction with respect to the housing 9, and is fixed in the rotation direction. And a plurality of balls 23 (steel balls) loaded between the thread grooves formed therein, so that the rotational motion of the main rotor 14 is converted into the linear motion of the outer body 22. . The thread grooves of the main rotor 14 and the outer body 22 form a right-hand thread. When the main rotor 14 rotates clockwise, the outer body 22 moves rightward in FIG. Thus, the brake pad 6 is pressed against the disk rotor 2.

Next, the pad wear compensating mechanism 13 will be described with reference to FIG. A female screw (trapezoidal screw) is formed on the inner peripheral portion of the inner body 19, and a male screw (trapezoidal screw) is formed on the outer peripheral portion of the piston 21, and these are screwed together to form an adjusting screw A. One end of 21 is in contact with the brake pad 5. The adjusting screw A of the inner body 19 and the piston 21 forms a left-hand thread,
The piston 21 moves toward the brake pad 5 by rotating the inner body 19 counterclockwise (counterclockwise as viewed from the right in FIG. 1; the same applies hereinafter). Further, the adjusting screw A of the inner body 19 and the piston 21 is self-locked even when a force is applied in the axial direction so that it does not rotate.

At the other end of the piston 21, a small-diameter spline portion 24 is integrally provided. To the spline portion 24, a cylindrical limiter 26 is mounted via a one-way clutch 25. The one-way clutch 25 has an inner portion that is connected to the spline portion 24 so as to be axially movable so as to be axially movable, and an outer portion that is fixed to a limiter 26.
Allow 26 clockwise rotation of spline 24,
For the counterclockwise rotation, the spline portion 24, that is, the piston 21 is integrally rotated. Here, it is desirable that the one-way clutch 25 has as little backlash as possible.

The limiter 26 is connected to the inner body 19 by a coil spring 27. The limiter 26 is held at a constant distance in the axial direction with respect to the inner body 19 regardless of the movement of the piston 21, and has a predetermined friction or It can rotate with elastic resistance. An arc-shaped groove 26A is formed in one end surface of a flange portion provided at one end portion of the limiter 26 along the circumferential direction within a range of a central angle (160 ° in the illustrated example) corresponding to a predetermined pad clearance. I have.

An annular rotor ring 28 is provided at the rear end of the main rotor 14 so as to face one end surface of the flange portion of the limiter 26.
Is mounted, and the pin set up on the rotor ring 28
29 is inserted into the groove 26A of the limiter 26. Piston 21
A hexagonal hole 30 is provided at the tip end of the spline portion 24, and when replacing the brake pads 5 and 6, the hexagonal hole 30 is formed through the opening 31 provided in the cover 16 and the central opening 32 of the rotor ring 28. , And the piston 21 can be rotated and moved.

The operation of the embodiment constructed as described above will now be described.

At the time of braking, the motor rotor 18 of the electric motor 10, ie, the main rotor 14, rotates clockwise in response to a control signal from a controller (not shown), and the first and second motors are rotated.
The ball screw mechanisms 11 and 12 operate to move the inner body 19 and the outer body 22 to the left and right in the figure, respectively, and press the brake pads 5 and 6 against the disk rotor 2 by the piston 21 and the pawl 4. To generate braking force. The rotational force acting on the brake pads 5 and 6 is supported by a carrier (not shown), and the caliper body 3 is guided by the carrier and moves, so that the sliding surfaces on both sides of the disk rotor 2 run out. In addition, an error in the separation distance between the brake pads 5 and 6 with respect to the disk rotor 2 before braking (the starting position at the time of braking) is absorbed.

At the time of braking release, when the electric motor 10 is rotated in the reverse direction and the main rotor 14 is rotated counterclockwise to the original position, the first and second ball screw mechanisms 11 and 12 together with the inner body 19 and the outer body 22 are used. The piston 21 and the claw portion 4 are retracted, and the brake pads 5 and 6 are separated from the disk rotor 2 to release the braking. At this time,
Piston by first and second ball screw mechanisms 11 and 12
Since the 25 and the claw portion 4 are retracted, the brake pads 5 and 6 on both sides can be evenly separated from the disk rotor 2, and the drag of the brake pads 5 and 6 can be reduced.

Next, the operation of the pad wear compensation mechanism 13 will be described with reference to FIGS. The piston
21 and brake pad 5 and claws 4 and brake pad 6
3 and FIG. 4 show only the relationship between the piston 21 and the brake pad 5.

When there is no wear on the brake pads 5 and 6,
Alternatively, after the wear adjustment described below is performed, as shown in FIG. 3, during braking, the piston 21 and the pawl 5 are moved from the non-braking position (A) to the pad by the clockwise rotation of the main rotor 14. The brake pads 5 and 6 are moved forward to the braking start position (B) where the brake pads 5 and 6 are brought into contact with the disk rotor 2 and the brake pads 5 and 6 are pressed against the disk rotor 2 to the braking position (C). Moving. Thereafter, when the braking is released by the counterclockwise rotation of the main rotor 14, the main rotor 14 moves backward to the non-braking position (A). At this time, if there is no wear on the brake pads 5 and 6, the piston
21 and the pawl 4 move within a certain range, and accordingly, the pin 29 of the rotor ring 28 rotates within a certain range within the groove 26A, and the limiter 26 does not rotate. No wear adjustment is performed.

When the brake pads 5 and 6 are worn, as shown in FIG.
The amount of movement of the piston 21 and the claw 4 during braking only increases, and the amount of rotation of the pin 29 of the rotor ring 28 also increases, so that the piston 21 and the claw 4 move from the non-braking position (A) to the braking position (D ), The pin 29 of the rotor ring 28 moves from one end to the other end of the groove 26A of the limiter 26. Further, when the pin 29 moves to the maximum braking position (E), the pin 29 Rotate clockwise. At this time, since the one-way clutch 25 idles, the piston 21 does not rotate. Thereafter, when the braking is released and the piston 21 and the claw 4 are retracted to the braking release position (F), the pin 29
Contacts the one end of the groove 26A and rotates the rotor ring 28 counterclockwise when returning to the original non-braking position (A). At this time, the one-way clutch 25 is engaged, the rotation of the rotor ring 28 is transmitted to the piston 21, and the piston 21 rotates counterclockwise to advance from the inner body 19 to the pad 5 side to adjust the pad wear. Do.

In this manner, the rotation range of the rotor ring 28 is increased by the wear of the brake pads 5 and 6, and the pin 29 is rotated beyond the range of the groove 26A of the limiter 26. Only the limiter 26 rotates to rotate the piston 21 through the one-way clutch 25 to advance the brake pad 5 side. Therefore, even if the strokes of the first and second ball screw mechanisms 11 and 12 are short, the brake pad 5 , 6 can be reliably adjusted. As a result, it is possible to increase the boost ratio by setting the leads of the first and second ball screw mechanisms 11 and 12 to be sufficiently small, so that the output of the electric motor 10 can be small and the power consumption can be reduced. The size of the motor can be reduced. Also,
Instead of the ball screw mechanism, a ball ramp mechanism having a small stroke and a large boost ratio can be used.
Further, since the pad wear compensation mechanism 13 is accommodated in the main rotor 14, the electric disc brake 1 can be downsized.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. The second embodiment is generally similar to the first embodiment except that the structure of the limiter of the pad wear adjusting mechanism is different. Therefore, the same parts as those of the first embodiment are not described. The same reference numerals are given and only different parts will be described in detail.

As shown in FIGS. 5 and 6, in the electric disc brake 33 of the second embodiment, a pad wear compensation mechanism is provided.
34 The limiter mechanism 35 is attached to the outer part of the one-way clutch 25A.
Are fitted. The one-way clutch 25A has an inner portion that is connected to the spline portion 24 so as to be axially movable so as to be movable in the axial direction, and an outer portion that is fixed to a limiter mechanism 35. Is allowed to rotate counterclockwise with respect to the spline portion 24, and the spline portion 24, that is, the piston 21 is integrally rotated with respect to the clockwise rotation. Here, it is desirable that the one-way clutch 25A has as little backlash as possible.

The limiter mechanism 35 has a substantially cylindrical limiter body 36 having a flange portion 36a formed on the outer periphery of an intermediate portion in the axial direction.
And a plurality (four in the illustrated case) of stacked disc springs 37 fitted externally to the limiter body 36 and abutting against one end surface of the flange portion 36a. Limiter ring 38 (limiter) and limiter body
A snap ring 39 which is fitted in the outer peripheral groove of 36 and supports the limiter ring 38 in the axial direction in a state where the disc spring 37 is compressed, comprises a limiter body 36 and a limiter ring 38.
The rotational force is transmitted by the frictional force of the disc spring 37 between and. On one end surface of the limiter ring 38, an arc-shaped groove 40 is formed along a circumferential direction within a range of a central angle (18 ° in the illustrated example) corresponding to a predetermined pad clearance. Pin 29 is inserted.
The limiter mechanism 35 has an inner body
The piston 21 is connected to the inner body 19 and is held at a fixed distance in the axial direction with respect to the inner body 19, regardless of the movement of the piston 21, and can rotate with a predetermined friction or elastic resistance.

The operation of the present embodiment having the above-described configuration will now be described. The basic operation at the time of braking is the same as in the first embodiment.

FIG. 7 shows the operation of the pad wear compensation mechanism 34.
This will be described with reference to FIG. Since the relative positional relationship between the piston 21 and the brake pad 5 and between the claw portion 4 and the brake pad 6 are the same, FIGS. 7 and 8 show only the relationship between the piston 21 and the brake pad 5.

When there is no wear on the brake pads 5 and 6,
Alternatively, after the wear adjustment described later is performed, as shown in FIG. 7, during braking, the rotation of the main rotor 14 causes the piston 21 and the claw portion 5 to advance forward from the non-braking position (A) by the pad clearance C. When the brake pads 5 and 6 move to the braking start position (B) where they come into contact with the disk rotor 2, the pins 29 of the rotor ring 28 are moved to the grooves 40 of the limiter ring 38.
And moves from one end of the groove 40 to the other end.
Further, the piston 21 and the claw portion 4 are
When the disc 6 is pressed to the disc rotor 2 and moved to the braking position (D), the pin 29 rotates the limiter ring 38 clockwise, and the rotating force is transmitted to the piston 21 via the disc spring 37 and the one-way clutch. You. At this time, since the piston 21 is pressing the brake pad 5 and the adjusting screw A between the piston 21 and the inner body 19 has a large frictional force, the disc spring 37 slips and the piston 21 rotates. do not do. When the brake is released, when the piston 21 and the claw portion 5 are retracted to the non-braking position (A) by the reverse rotation of the main rotor 14, the pin 29 comes into contact with one end of the groove 40 and the limiter mechanism is released.
Although 35 is rotated counterclockwise, the piston 21 does not rotate because the one-way clutch 15A idles. In this way, pad wear is not adjusted and constant pad clearance is maintained.

When the brake pads 5 and 6 are worn, as shown in FIG. 8, during braking, the clockwise rotation of the main rotor 14 moves the brake pads 5 and 6 from the non-braking position (A) by the amount of the pad clearance C. The piston 21 and the claw 5 do not press the brake pads 5 and 6 due to the wear W even if the pin 29 moves to the position (B) and the pin 29 moves from one end to the other end of the groove 40. When the main rotor 14 further rotates, the inner body 16 and the outer body 22 (claw portion 4) advance to the position (D) toward the disk rotor 2 and the piston
21 and the pawl portion 4 bring the brake pads 5 and 6 into contact with the disk rotor 2. At this time, the pin 29 is limited
38 is rotated clockwise, and the rotational force is transmitted to the piston 21 via the disc spring 37 and the one-way clutch 15A, but the piston 21 does not press the brake pad 5,
Since no large frictional force is generated in the adjusting screw A between the piston 21 and the inner body 19, the piston 21 rotates clockwise to advance from the inner body 19 to the brake pad 5 side, and the wear of the pad is adjusted. You. When the piston 21 moves to the position (E) by pressing the brake pad 5 against the disk rotor 2, the piston 21 and the inner body are moved.
A large frictional force is generated on the adjusting screw A between the disc spring 19 and the disc spring 37.
And the rotation of the piston 21 stops. And
When the brake is released, when the piston 21 and the claw 5 are retracted to the non-braking position (A) by the counterclockwise rotation of the main rotor 14, the pin 29 abuts one end of the groove 40 to rotate the limiter mechanism 35 counterclockwise. The piston 21 does not rotate because the one-way clutch 15A idles. In this way,
1 for a fixed percentage of the wear of the brake pads 5 and 6
By this operation, the piston 21 can be advanced from the inner body 19 to the brake pad 5 side. By repeating this, the wear of the pad can be adjusted, and the same effects as in the first embodiment can be obtained.

In the first and second embodiments,
Although an example in which a ball screw mechanism is used as the screw transmission mechanism has been described, the present invention is not limited to this, as long as it converts the rotational movement of the motor into the linear movement of the piston.
The present invention can be similarly applied to those using other screw transmission mechanisms such as a ball ramp mechanism. Further, in the first and second embodiments, an example is described in which a screw mechanism that opens and closes on both sides is used, but the present invention can also be applied to a mechanism that advances and retreats only in one direction (for example, only the piston).

[0039]

As described in detail above, according to the electric disk brake of the first aspect, the provision of the pad wear compensation mechanism causes the brake pads to wear, and the rotational displacement of the rotor of the electric motor during braking. Exceeds a predetermined range, the rotational displacement exceeding the predetermined range is transmitted to the adjustment screw via the one-way clutch when braking is released, and the piston advances to the disk rotor side. Thus, the piston can be advanced, and the wear of the pad can be appropriately adjusted. Further, since the correction operation is performed when the piston is retracted (when the brake is released), the loss due to wear can be minimized.

According to the electric disk brake of the present invention, the pad wear compensation mechanism is provided, so that when the brake pad wears out and the rotational displacement of the rotor of the electric motor during braking exceeds a predetermined range, Rotational displacement exceeding the predetermined range is transmitted to the adjusting screw via the friction transmission mechanism and the one-way clutch, and the piston advances toward the disk rotor. At this time, if the piston is pressing the brake pad against the disc rotor, a large frictional force is generated on the adjusting screw, and the friction transmitting mechanism slips and the adjusting screw does not rotate. Thus, the piston can be advanced, and the wear of the pad can be appropriately adjusted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric disc brake according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of a pad wear compensation mechanism of the apparatus of FIG.

FIG. 3 is an explanatory view showing an operation of the pad wear compensation mechanism of the apparatus shown in FIG. 1 when there is no pad wear;

FIG. 4 is an explanatory view showing an operation when a pad of a pad wear compensation mechanism of the apparatus of FIG. 1 is worn.

FIG. 5 is a longitudinal sectional view of an electric disc brake according to a second embodiment of the present invention.

6 is an exploded perspective view of a pad wear compensation mechanism of the device of FIG.

FIG. 7 is an explanatory diagram showing an operation of the pad wear compensation mechanism of the apparatus of FIG. 5 when there is no pad wear.

FIG. 8 is an explanatory diagram showing an operation when a pad of a pad wear compensation mechanism of the apparatus of FIG. 5 is worn.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric disc brake 2 Disc rotor 5, 6 Brake pad 14 Main rotor (rotor) 11 1st ball screw mechanism (transmission mechanism) 12 2nd ball screw mechanism (transmission mechanism) 13,34 Pad wear compensation mechanism 21 Piston 25, 25A One-way clutch 26 Limiter 37 Disc spring (friction transmission means) 38 Limiter ring (Limiter) A Adjustment screw

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toma Yamaguchi 1-6-3 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa F-term in Tokiko Corporation (reference) 3J058 AA43 AA48 AA53 AA63 AA69 AA73 AA78 AA83 AA87 BA41 BA57 CC15 CC63 CC77 DA17 DA29 DA32 FA01

Claims (2)

[Claims] An electric disk which converts a rotational movement of a rotor by an electric motor into a linear movement of a piston via a transmission mechanism, and presses a brake pad against a disk rotor by movement of the piston to generate a braking force. In the brake device, an adjusting screw is provided between the transmission mechanism and the piston,
Between the adjusting screw and the rotor, a limiter that transmits only a rotational displacement exceeding a predetermined range of the rotor and a one-way clutch are provided, and when the rotational displacement during braking of the rotor exceeds a predetermined range, A pad wear compensation mechanism is provided which transmits the rotational displacement at the time of braking release of the rotor to the adjustment screw via the one-way clutch to advance the piston toward the disk rotor. Electric disc brake. 2. An electric disk wherein a rotational movement of a rotor by an electric motor is converted into a linear movement of a piston via a transmission mechanism, and the movement of the piston presses a brake pad against a disk rotor to generate a braking force. In the brake device, an adjusting screw is provided between the transmission mechanism and the piston,
A limiter for transmitting only a rotational displacement exceeding a predetermined range of the rotor, a friction transmitting means for transmitting a rotational force by frictional force, and a one-way clutch between the adjusting screw and the rotor; When the rotational displacement at the time of braking exceeds a predetermined range, the rotational displacement over the predetermined range is transmitted to the adjusting screw via the friction transmission mechanism and the one-way clutch to move the piston to the disk rotor side. An electric disc brake, comprising: a pad wear compensation mechanism configured to move forward.