JP2008157378A - Motor-driven disc brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a self locking state in a backing end of a rotary-to-liner motion converting mechanism in a motor-driven disc brake. <P>SOLUTION: A rotary motion of a rotor 48 in an electric motor 39 is decelerated by a speed reduction mechanism 20 to drive a ball ramp mechanism 19 and thereby brake pads 4, 5 are pressed to a disc rotor 2 to generate braking force. In exchanging the brake pads 3, 4 or otherwise, when the rotor 48 is inversely rotated, an adjusting screw 16 is rotated by a differential speed reduction mechanism 20 and thereby the adjusting screw 16 is retreated by engagement between a male screw 17 and a female screw 18. When the adjusting screw 16 has reached the retreated end, an abutting portion 57 in the adjusting screw 16 abuts against a stopper formed in a motor case 44 in a rotational direction to stop the adjusting screw 16 there. At that time, the self-locking state can be prevented because axial force is not yielded in the male and female screws 17, 18. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric disc brake that generates a braking force by pressing a brake pad against a disc rotor by an electric motor.

  As an electric disc brake, the rotary motion of the rotor of the electric motor is converted into a linear motion of the piston using a rotation-linear motion conversion mechanism such as a ball screw mechanism, a ball ramp mechanism, and the brake pad is pressed against the disc rotor, What generates a braking force is known. The electric disc brake detects a driver's brake pedal depression force (or displacement) by a sensor, and a control device controls the rotation of the electric motor based on the detected value to generate a desired braking force.

  In an electric disc brake having such a rotation-linear motion conversion mechanism, it may be necessary to operate the rotary actuator to retract the piston to the retracted end for the purpose of replacing the brake pad, calibrating the piston position, or the like. is there. At this time, if the linear motion of the rotation-linear motion conversion mechanism is hindered at the retracted end, an axial force acts on the rotation-linear motion conversion portion such as a screw portion, and the rotation-linear motion conversion mechanism is self-locked. There is.

Therefore, for example, in the electric disc brake described in Patent Document 1, the axial force generated in the rotation-linear motion conversion mechanism is detected near the retracted end of the piston using a thrust sensor that detects the thrust of the piston, and self-locking. The operation of the electric motor is stopped before this occurs.
JP-A-2005-226752

  However, when the above-described technology for preventing self-locking using a piston thrust sensor is applied to an electric disc brake that does not include a thrust sensor, it is necessary to add a thrust sensor separately, and the manufacturing cost and thrust There is a problem in terms of sensor mounting space.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an electric disc brake that can prevent excessive retreat at the retreat end of the rotation-linear motion conversion mechanism.

In order to solve the above-described problems, an invention according to claim 1 is directed to an electric disk that moves a brake pad by converting rotation of a rotor of an electric motor provided in a caliper body into linear motion by a rotation-linear motion conversion mechanism. In braking,
The rotation-linear motion conversion mechanism includes a rotating member that is rotated by the rotor, and a non-rotating member that linearly moves with respect to the rotating member by the rotation of the rotating unit, and a contact portion is provided on the rotating member. When the stopper portion facing the corresponding contact portion is fixed to the caliper body side and the rotating member moves to a predetermined retracted end by the rotation, the contact portion is in the rotation direction of the rotating member. To prevent rotation of the rotating member.
According to a second aspect of the present invention, there is provided the electric disc brake according to the first aspect, wherein the non-rotating member is integrally fixed to the caliper body, and the stopper portion is a member different from the non-rotating member. It is fixed to the caliper main body via
According to a third aspect of the present invention, there is provided the electric disc brake according to the second aspect, wherein the stopper member is fixed to the electric motor disposed in the retreating direction of the rotating member.
According to a fourth aspect of the present invention, in the electric disc brake according to the third aspect, the electric motor includes a motor case that covers the rotor and the stator, and the stopper portion is formed in the motor case. It is characterized by.

According to the electric disc brake of the first aspect of the invention, when the rotating member of the rotation-linear motion converting mechanism reaches the retracted position, the rotating member rotates with the contact portion contacting the stopper portion in the rotation direction. Therefore, it is possible to prevent excessive retreat, and it is possible to prevent the rotation-linear motion conversion mechanism from self-locking due to generation of an axial force.
According to the electric disc brake of the second aspect of the invention, the movement of the rotating member is not restricted before the member other than the non-rotating member for fixing the stopper portion to the caliper body is attached to the caliper body. The degree of freedom of incorporation into the caliper body can be increased.
According to the electric disc brake of the third aspect of the invention, since the movement of the rotating member is not restricted before the electric motor is attached to the caliper main body, the degree of freedom of assembling the rotating member into the caliper main body can be increased.
According to the electric disc brake of the invention of claim 4, the stopper portion can be fixed to the caliper body by attaching the electric motor to the caliper body.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
A first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the electric disc brake 1 according to the present embodiment is a caliper floating disc brake, and includes a disc rotor 2 that rotates together with wheels, and a non-rotating portion on the vehicle body side such as a suspension member ( A carrier 3 fixed to the disk rotor 2, a pair of brake pads 4 and 5 disposed on both sides of the disk rotor 2 and supported by the carrier 3, and a pair of slide pins disposed across the disk rotor 2. And an electric caliper 7 supported by the carrier 3 so as to be movable along the axial direction of the disk rotor 2 (not shown). The electric caliper 7 includes a caliper body 8, a piston unit 9, and a motor / control device unit 10.

  The caliper main body 8 has a cylindrical cylinder portion 11 formed of a through hole having one end opposed to one side of the disk rotor 2, and a claw portion 12 extending from the cylinder portion 11 to the opposite side across the disk rotor 2. A pair of boss portions 13 extending from the cylinder portion 11 substantially in the diameter direction and to which a pair of slide pins are respectively attached are integrally formed. A guide bore 15 into which the piston 14 of the piston unit 9 is slidably fitted and an internal thread 18 of an adjustment screw 16 attached to the piston unit 9 are screwed onto the inner peripheral surface of the cylinder portion 11. And are formed.

  The piston unit 9 includes a bottomed cylindrical piston 14, a ball ramp mechanism 19 (rotation-linear motion conversion mechanism) and a differential reduction mechanism 20 housed in the piston 14, and a pad wear tracking mechanism 21. It has become. The piston 14 is slidably fitted to the guide bore 15 of the caliper body 8, contacts the one brake pad 5, and is prevented from rotating by a pin 5A. The piston 14 and the guide bore 15 are sealed with a dust seal 22 and a seal ring 23.

  The ball ramp mechanism 19 includes a linear motion disk 24 fixed to the bottom surface of the piston 14, a rotation disk 25 that can rotate and move in the axial direction, and a ball groove 26 formed on the surfaces facing each other. 27 (inclined groove) and a ball 28 (rolling element) inserted. The rotating disk 25 is constantly urged toward the linear motion disk 24 by a spring 29. When the linear motion disk 24 and the rotary disk 25 are rotated relative to each other, the balls 28 roll between the inclined ball grooves 26 and 27, so that the linear motion disk 24 and the rotary disk 25 correspond to the rotation angle. Move relative to the axis. Thereby, a rotational motion can be converted into a linear motion.

  The differential reduction mechanism 20 includes a rotary shaft 30, a ring-shaped external gear member 32 having two external teeth 32A and 32B that are rotatably fitted to the eccentric portion 31 of the rotary shaft 30 by bearings 31A and 31B, An internal gear 33 formed on the rotary disk 25 of the ball ramp mechanism 19 and meshing with one external tooth 32A of the external gear member 32, and an external gear supported rotatably by a bearing 35A with respect to the rotary shaft of the rotary shaft 30. And a rotating disk 35 having an internal tooth 34 that meshes with the other external tooth 32B of the member 32. A rotating disk 25 is rotatably supported at one end of the rotating shaft 30 by a bearing 25A. The other end of the rotating shaft 30 extends into the motor / control device unit 10 and an outer spline 36 is formed at the tip.

  One end of the rotating disk 35 is in contact with the end of the rotating disk 25 via a ball thrust bearing 37 and is pressed against the rotating disk 25 by a spring 29 to urge the rotating disk 25 toward the linearly moving disk 24. ing. The center distance between the external gear member 32 and the rotating disk 25 where the external teeth 32A and the internal teeth 33 mesh with each other, and the center distance between the external gear member 32 and the rotating disk 35 where the external teeth 32B and the internal teeth 34 mesh with each other. Since it is determined by one rotating shaft 30, the positioning accuracy can be increased. Further, a lateral force is applied to the rotating disk 25 and the rotating disk 35 by a reaction force caused by the meshing of these gears. However, due to a biasing force of the spring 29 and a reaction force transmitted from the brake pad 5 to the rotating disk 25. In addition to preventing the rotating disk 25 and the rotating disk 35 from falling over, it is possible to eliminate rattling and to prevent generation of vibration and noise.

  Then, by rotating the rotary shaft 30 and revolving the external gear member 32, the rotary disk 25 having the internal teeth 33 meshing with the external teeth 32A of the external gear member 32 and the internal teeth 34 meshing with the external teeth 32B are provided. By rotating differentially with the rotary disk 35 and fixing one of them, the other can be decelerated and rotated at a predetermined reduction ratio. In addition, by setting the number of teeth of the external teeth 32A and the external teeth 33A of the differential reduction mechanism 20 to the same number, the external teeth 32A and the external teeth 33A can be machined integrally, and the manufacturing cost can be reduced. it can.

  The pad wear following mechanism 21 includes a limiter 38 mounted between the linear motion disk 24 and the rotary disk 25 of the ball ramp mechanism 19, an adjustment screw 16 coupled to the rotary disk 35 of the differential reduction mechanism 20, and a rotation. A cup 38B coupled to the disk 35 and a wave washer 38A interposed between the piston 14 and the cup 38B are provided. The limiter 38 applies a biasing force in the return direction with a certain amount of play between the linear motion disk 24 and the rotary disk 25 by a torsion spring. The adjustment screw 16 has a male screw 17 (trapezoidal screw) formed on the outer periphery thereof, and the male screw 17 is screwed into a female screw 18 (trapezoidal screw) formed on the cylinder portion 11 of the caliper body 8. Thereby, the connection of the rotary disk 35 constituting the differential reduction mechanism 20 to the cylinder portion 11 can be used also as the adjustment screw 16 of the pad wear follow-up mechanism 21, and the number of parts and the processing portion can be reduced. . The adjustment screw 16 is held so as not to rotate with a constant holding force by the wave washer 38A, and is moved in the axial direction by the relative rotation of the male screw 17 and the female screw 18 by rotating against the holding force. Can do. That is, a rotation-linear motion conversion mechanism is configured by screwing the external screw 17 of the adjusting screw 16 (rotating member) and the internal screw 18 of the cylinder portion (non-rotating member). Further, the adjusting screw 16 receives the reaction force from the rotating disk 25 via the thrust bearing 37 and the rotating disk 35 and transmits the reaction force to the caliper body 8 via the male screw 17 and the female screw 18.

  The motor / control device unit 10 controls the drive of the electric motor 39, the resolver 40 that detects the rotational position of the electric motor 39, the parking brake mechanism 41 that fixes the rotational position of the electric motor 39, and the electric motor 39. For this purpose, a drive control device 42 is integrated with a base plate 43.

  The electric motor 39 is made of an iron-based material that is attached to the one surface 43A side of the aluminum base plate 43 that is coupled to the end portion of the caliper body 8 and is inserted into the adjustment screw 16 of the piston unit 9 and has a bottomed cylindrical shape. A motor case 44 is provided, and a motor stator 45 made of a coil or the like is fixed to the inner periphery of the motor case 44. The motor case 44 includes a substantially bottomed cylindrical motor case main body 44A and a motor case lid 44B that closes the opening thereof, and bearings 46, 47 are provided at the bottom of the motor case main body 44A and the central opening of the motor case lid 44B. The cylindrical motor rotor 48 is rotatably supported by these bearings 46 and 47. The motor case 44 abuts on the inner periphery of the cylinder portion 11 of the caliper body 8 and is supported in the radial direction. An inner spline 49 that engages with the outer spline 36 of the rotation shaft 30 of the piston unit 9 is formed on the inner peripheral portion of the rotor 48, and transmits rotational force between the rotor 48 and the rotation shaft 30. These can be moved relative to each other in the axial direction. If the rotor 48 is movable in the axial direction with respect to the motor stator 45, the rotor 48 and the rotary shaft 30 may be integrally formed.

The resolver 40 is attached to the resolver stator 50 fixed to the other surface 43B side of the base plate 43 opposite to the electric motor 39, and the tip of the rotor 48 inserted through the base plate 43 so as to face the resolver stator 50. And a resolver rotor 51. The resolver 40 outputs an electrical signal indicating the rotational speed and rotational position of the rotor 48 by these relative rotations.
The parking brake mechanism 41 operates the lock mechanism 52 with an electric actuator to lock the rotation of the rotor 48.

  The drive control device 42 is a control circuit mounted on a base mounted on the opposite side of the base plate 43 from the electric motor 39, and is connected to the electric motor 39 by a wire 45A, and is connected to the resolver 40 by a wire 50A. A braking force signal commanded from an in-vehicle controller (not shown) mounted on the vehicle body side in order to execute a brake pedal operation by the driver or automatic brake control such as traction control and vehicle stabilization control, and Based on the rotational position signal from the resolver 40, a drive signal is supplied to the electric motor 39 to control the rotation of the electric motor 39. A cover 53 that covers the resolver 40 and the drive control device 42 is attached to the base plate 43.

  Next, the stopper mechanism 54 that defines the retracted end of the adjustment screw 16 by the rotation of the electric motor 39 will be described with reference to FIGS.

  As shown in FIG. 3, the side wall of the substantially bottomed cylindrical motor case main body 44A of the electric motor 39 has a stepped shape having a small-diameter portion 55 on the bottom side and a large-diameter portion 56 on the opening side. 55 is inserted into the adjusting screw 16, the large diameter portion 56 is larger in diameter than the male screw 17 of the adjusting screw 16, and the end surface of the large diameter portion 56 on the small diameter portion 55 side is the end of the adjusting screw 16 on the male screw 17 side. Opposite. An arcuate abutting portion 57 extending in the circumferential direction protrudes in the axial direction at the end of the adjusting screw 16 on the male screw 17 side, and the circumferential end of the abutting portion 57 extends in the circumferential direction. An orthogonal contact surface 57A is formed. The motor case main body 44A is formed with a substantially arcuate stopper portion 58 that protrudes from the end surface of the large diameter portion 56 on the small diameter portion 55 side to face the end surface of the adjustment screw 16 on the male screw 17 side. A stopper surface 58A orthogonal to the circumferential direction is formed at the circumferential end of the stopper portion 58. An opening 59 cut out from the small diameter portion 55 to the large diameter portion 56 is formed on the side wall of the motor case main body 44A, and the end portion of the stopper portion 58 is cut by the opening 59, and the stopper surface is cut by the cut surface. A surface 58A is formed. Then, when the adjusting screw 16 rotates and moves in the axial direction by screwing the male screw 17 and the female screw 18 on the cylinder portion 11 side and reaches the retracted end, the contact portion 57 of the adjusting screw 16 The contact surface 57A is in contact with the stopper surface 58A of the stopper portion 58 of the motor case main body 44A in the rotation direction of the adjustment screw 16, thereby preventing the adjustment screw 16 from rotating.

The operation of the present embodiment configured as described above will be described next.
During braking, the in-vehicle controller detects the brake pedal depression force (or displacement amount) of the driver by a brake pedal sensor, and based on this detection value, sends a braking force signal to the drive control device 42 of the electric disc brake 1 of each wheel. Send. The drive control device 42 outputs a drive voltage to the electric motor 39 based on the braking force signal from the in-vehicle controller, and rotates the rotor 48 by a desired rotation angle with a desired torque. The rotation of the rotor 48 is decelerated at a predetermined reduction ratio by the differential reduction mechanism 20 and converted into a linear motion by the ball ramp mechanism 19 to advance the piston 14. As the piston 14 advances, one brake pad 5 is pressed against the disk rotor 2, and the reaction force causes the caliper body 8 to move along the slide pin of the carrier 3, so that the claw portion 12 moves the other brake pad 4 to the disk. Press against the rotor 2. When releasing the brake, the rotor 48 is rotated in the reverse direction to retract the piston 14 and separate the brake pads 4 and 5 from the disc rotor 2.

  The vehicle controller detects the vehicle state such as the rotational speed of each wheel, the vehicle speed, the vehicle acceleration, the steering angle, and the vehicle lateral acceleration using various sensors, and the electric motor 39 is rotated based on these detections. By controlling, boost control, anti-lock control, traction control, vehicle posture stabilization control, and the like can be executed.

Next, the operation of the differential reduction mechanism 20 and the pad wear tracking mechanism 21 will be described.
When the rotary shaft 30 is rotated by the rotor 48 during braking, the external gear member 32 revolves due to the eccentric rotation of the eccentric portion 31, and the rotary disk 25 and the rotary disk 35 meshed with the external teeth 32 </ b> A and 32 </ b> B of the external gear member 32. Rotates differentially. At this time, normally, the rotation of the rotary disk 35 together with the adjustment screw 16 is fixed by the wave washer 38A. On the other hand, the rotary disk 25 can freely rotate within the range of play of the limiter 38. Rotates. As a result, the ball ramp mechanism 19 advances the piston 14 and presses the brake pads 4 and 5 against the disc rotor 2. After the brake pads 4 and 5 start to press the disk rotor 2, the reaction force acts on the male screw 17 and the female screw 18, thereby increasing the frictional force between them, so that the adjusting screw 16, that is, the rotary disk 35 is moved. The rotation is securely locked. Therefore, the rotary disk 25 can rotate against the spring force of the limiter 38.

  If the brake pads 4 and 5 are worn and the disk rotor 2 is not pressed even when the rotating disk 25 exceeds the range of play of the limiter 38, the spring force of the limiter 38 acts on the rotating disk 25, and the rotating disk 25 is The adjusting screw 16 is rotated together with the rotating disk 35 against the holding force of the wave washer 38A. Thereby, the adjustment screw 16 moves forward by the relative rotation of the male screw 17 and the female screw 18 to advance the piston unit 9. When the brake pads 4 and 5 move forward by the amount of wear and press the disk rotor 2, as described above, the frictional force of the male screw 17 and the female screw 18 is increased by the reaction force, and the rotation of the adjusting screw 16 is locked. Is done. Thereafter, the rotating disk 25 rotates against the spring force of the limiter 38 and the piston 14 advances by the ball ramp mechanism 19. In this way, the piston unit 9 can be advanced by the adjusting screw 16 by the amount of wear of the brake pads 4 and 5, and wear of the brake pads 4 and 5 can be compensated.

  Next, a case where the piston 14 is moved to the backward end when the brake pads 4 and 5 are replaced will be described. As in the case of the brake release described above, when the drive control device 42 outputs a drive voltage to the electric motor 39 to rotate the rotor 48, the rotating disk 25 of the ball ramp mechanism 19 returns to the original position and cannot be rotated any further. For this reason, the differential screw 16 rotates the adjusting screw 16 against the holding force of the wave washer 38 </ b> A in the backward direction to further retract the piston 14. When the adjustment screw 16 reaches its retracted end, as shown in FIG. 5, the contact surface 57A of the contact portion 57 of the adjustment screw 16 contacts the stopper surface 58A of the stopper portion 58 of the motor case main body 44A. The rotation of the adjusting screw 16 stops. At this time, since the contact portion 57 prevents the adjustment screw 16 from rotating by contacting the stopper portion 58 in the rotation direction of the adjustment screw 16, when the adjustment screw 16 reaches its retracted end, the male screw 17 and the female screw 18 No axial force is generated between the male screw 17 and the self-locking of the male screw 17 and the female screw 18.

  Since the stopper portion 58 is formed on the motor case main body 44A of the electric motor 39, the piston unit 9 including the adjusting screw 16 is attached to the cylinder portion 11 of the caliper main body 8 before the electric motor 39 is attached to the caliper main body 8. The electric caliper 7 can be assembled easily by assembling the motor / control unit 10 after inserting the piston unit 9 into the caliper body 8 since it can be inserted from the opposite side of the portion 12. Moreover, since it is not necessary to provide the notch 12 in the nail | claw part 12 for assembling the piston unit 9 to the caliper main body 8, the rigidity of the nail | claw part 12 does not fall by a notch.

  In the first embodiment described above, a general involute gear is used as a differential speed reduction mechanism. Similarly, a speed reduction mechanism using a cycloid groove and a ball, and a cycloid gear and a pin are used. Other known differential reduction mechanisms such as a reduction mechanism can also be used.

  Next, a second embodiment of the present invention will be described with reference to FIG. In addition, with respect to the said 1st Embodiment, the same code | symbol is attached | subjected to the same part, and only a different part is demonstrated in detail.

  As shown in FIG. 6, in the electric disc brake 60 according to the second embodiment, a ball screw mechanism 61 is used instead of the ball ramp mechanism 19 as the rotation-linear motion conversion mechanism, and the pad wear tracking mechanism 21 is It is omitted. A fixed disk 62 is provided instead of the rotating disk 25, and the fixed disk 62 extends to the bottom of the piston 14 and is fixed to the piston 14.

  The ball screw mechanism 61 includes a rotary linear motion member 63 (rotary member) provided in place of the adjusting screw 16 and a ball groove 64 (non-rotating member) provided in place of the female screw 18 on the inner peripheral surface of the cylinder portion 11. A spiral ball groove 65 formed on the outer peripheral surface of the rotary linear motion member 63, a plurality of balls 66 (rolling bodies) loaded between these ball grooves 64, 65, and these balls 66 as balls And a circulation passage (not shown) for circulation between the grooves 64 and 65.

  As a result, in the operating speed reduction mechanism 20, when the rotating shaft 30 is rotated by the rotor 48 and the external gear member 32 is revolved by the eccentric shaft 31, the fixed disk 62 is fixed in the rotating direction. The motor rotates at a predetermined reduction ratio. Therefore, when the rotor 48 of the electric motor 39 is rotated, the rotation / linear motion member 63 is decelerated and rotated by the differential reduction mechanism 20 and moved in the axial direction by the ball screw mechanism 61. The axial movement of the rotary translation member 63 is transmitted to the piston 14 via the rotary disk 35, the external gear member 32, the thrust bearing 37 and the fixed disk 62, and presses the brake pads 4 and 5 against the disk rotor 2. Further, the disk rotor 2 is retracted.

  In this case, the ball screw mechanism 61 has a sufficiently large stroke of linear motion as compared with the ball ramp mechanism 19 and the rotary linear motion member 63 can follow the wear of the brake pads 4 and 5. 21 need not be provided.

  Similar to the first embodiment, the electric disc brake 60 is provided with a stopper mechanism 54 for defining the retracted end of the rotary linear motion member 63 by the rotation of the electric motor 39. The rotary linear motion member 63 includes an adjustment screw. Similar to 16, a contact portion 57 that forms a contact surface 57A is provided. As a result, when the rotary linear motion member 63 is retracted to its retracted end, the contact surface 57A of the contact portion 57 contacts the stopper surface 58A of the stopper portion 58 of the motor case main body 44A. The rotation stops and the retreat thereof is restricted, and the excessive receding of the rotation linear motion member 63 can be prevented.

  In the first embodiment, a roller ramp mechanism can be used instead of the ball ramp mechanism. In the second embodiment, a roller screw mechanism can be used instead of the ball screw mechanism. It is also possible to use another known rotation-linear motion conversion mechanism instead of the above.

1 is a longitudinal sectional view showing an electric disc brake according to a first embodiment of the present invention. It is a front view of the electric disc brake of FIG. It is a disassembled perspective view of the piston unit and electric motor which show the stopper mechanism of the electric disc brake of FIG. In the longitudinal cross-sectional view by the AA line of the electric disc brake of FIG. 1, it is a figure which shows the state which the contact part and stopper part of a stopper mechanism are not contacting. In the longitudinal cross-sectional view by the AA line of the electric disc brake of FIG. 1, it is a figure which shows the state which the contact part and stopper part of the stopper mechanism contact | abutted. It is a longitudinal cross-sectional view which shows the electric disc brake which concerns on 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Electric disc brake, 2 Disc rotor, 4, 5 Brake pad, 11 Cylinder part (non-rotating member), 8 Caliper main body, 16 Adjustment screw (rotating member), 19 Ball ramp mechanism (rotation-linear motion conversion mechanism), 39 Electric motor, 44 Motor case, 57 Contact part, 58 Stopper part

Claims (4)

In the electric disk brake that moves the brake pad by converting the rotation of the rotor of the electric motor provided in the caliper body into a linear motion by the rotation-linear motion conversion mechanism,
The rotation-linear motion conversion mechanism includes a rotating member that is rotated by the rotor, and a non-rotating member that linearly moves with respect to the rotating member by the rotation of the rotating unit, and a contact portion is provided on the rotating member. When the stopper portion facing the corresponding contact portion is fixed to the caliper body side and the rotating member moves to a predetermined retracted end by the rotation, the contact portion is in the rotation direction of the rotating member. An electric disc brake characterized in that the rotation of the rotating member is prevented by contacting the rotating disc. The non-rotating member is integrally fixed to the caliper main body, and the stopper portion is fixed to the caliper main body via a member different from the non-rotating member. The electric disc brake described. The electric disk brake according to claim 2, wherein the stopper member is fixed to the electric motor disposed in a backward direction of the rotating member. The electric disk brake according to claim 3, wherein the electric motor includes a motor case that covers the rotor and the stator, and the stopper portion is formed on the motor case.

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