JP2011179569A - Disc brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disc brake easily manufactured at low cost. <P>SOLUTION: A carrier part is constituted of two components: a carrier 41 and a holder 85, and the carrier 41 and the holder 85 are connected together only by a pin 84 placed on the axial line common between them. In this way, coaxiality of a planet gear mechanism 36 can be secured easily, and a mounting hole for each of pins 47 supporting planetary gears 45 of the planetary gear mechanism 36 is arranged only one of the two components. In this way, increase in production cost is prevented while productivity is improved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a disc brake.

  2. Description of the Related Art Conventionally, there is known an electric disc brake that propels a piston by decelerating the rotation of an electric motor by a planetary gear mechanism and converting the decelerated rotation to a linear motion by a rotation / linear motion conversion mechanism (for example, Patent Document 1).

JP-T-2002-541414

In such a disc brake, the assemblability can be improved by sub-assembling the planetary gear mechanism. For example, a carrier that supports a plurality of planetary gears (planetary gears) is divided into two parts in the axial direction, and both parts are positioned relative to each other using pins that rotatably support each planetary gear. The structure to make it known is known. Since this structure manages the positioning accuracy (casing processing accuracy) of the pin holes formed in both parts, the manufacturing tends to be complicated.
An object of the present invention is to provide a disc brake that is easy to manufacture.

  In order to solve the above problems, a disc brake according to the present invention includes a pressing member that is provided in a cylinder of a caliper body and presses a brake pad against a disc rotor, an electric motor attached to the caliper body, and rotation of the electric motor. A speed reduction mechanism that increases the force, a rotation / linear motion conversion mechanism that converts the rotational force increased by the speed reduction mechanism into linear motion, and the pressing member is propelled by the linear motion obtained by the rotation / linear motion conversion mechanism And a parking brake mechanism that holds the pushed pressing member in a parking braking position, wherein the speed reduction mechanism includes a sun gear to which rotational force from the electric motor is input / output, A plurality of planetary gears revolving around the rotation axis of the sun gear, an internal gear meshed with each planetary gear, and each planetary gear rotatably supported And a carrier member to which rotational force from the electric motor is input / output by rotating along with the revolution of each planetary gear, and the carrier member is axial with respect to the plurality of planetary gears. A first shaft portion that is located on one side and is pivotally supported on the caliper body, and a second shaft portion that is pivotally supported on the caliper body on the opposite side of the first shaft portion with respect to the plurality of planetary gears. A supporting portion that rotatably supports the plurality of planetary gears on the first shaft portion only on one axial side thereof, and the first shaft portion extending between the plurality of planetary gears. And a bridging portion for integrally joining the second shaft portion.

  A disc brake that is easy to manufacture can be provided.

It is a longitudinal cross-sectional view of the disc brake of this embodiment. It is sectional drawing when the ball lamp mechanism of this embodiment is cut | disconnected by the uniaxial perpendicular plane. It is a perspective view of the holder of the planetary gear mechanism of this embodiment. It is sectional drawing when the planetary gear mechanism of this embodiment is cut | disconnected by the uniaxial perpendicular plane on an internal gear. It is sectional drawing when the rotation control mechanism of this embodiment is cut | disconnected by the uniaxial perpendicular plane on a carrier. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove. (A) is operation | movement explanatory drawing of the parking brake mechanism of this embodiment, Comprising: It is sectional drawing when cut | disconnected by the same plane as FIG. 5, (B) is a ball lamp mechanism corresponding to the state of (A). Represents the position of the ball with respect to the ball groove.

  An embodiment of the present invention will be described with reference to the accompanying drawings. In the present embodiment, the caliper floating type electric disc brake 1 shown in FIG. 1 will be described. The disc brake 1 includes a disc rotor 1A that rotates together with the wheels, a carrier 5 that is fixed to a non-rotating portion (not shown) on the vehicle body side such as a knuckle, and both axial sides of the disc rotor 1A (left and right direction in FIG. 1) It has a pair of brake pads 2 and 3 that are disposed and supported by the carrier 5 and a caliper 4 that is supported by the carrier 5 so as to be movable in the axial direction of the disk rotor 1A. The caliper body 6 that is the main body of the caliper 4 is formed in a cylindrical shape on the base side facing the inner pad 2, and extends from the cylinder portion 7 across the disk rotor 1 </ b> A to face the outer pad 3. And a claw portion 8 provided on the leading end side. The cylinder portion 7 has a bottomed cylinder 10 having an inner pad 2 side opened and a bottom wall 9 on the opposite side (right side in FIG. 1).

  In the cylinder 10 of the cylinder portion 7, a piston 12 (pressing member) which is formed in a bottomed cylindrical shape and is directed so that the bottom portion faces the inner pad 2 is slidably accommodated in the cylinder 10. A piston seal 11 housed in a groove formed in an annular shape along the circumferential direction of the cylinder 10 is provided on the inner wall of the cylinder 10. The outer peripheral surface of the piston 12 is movably in contact with the inner peripheral surface of the piston seal 11. The caliper main body 6 has a hydraulic pressure chamber 13 defined by the bottom wall 9 and the piston 12. In the hydraulic pressure chamber 13, a hydraulic pressure from a hydraulic pressure supply source such as a master cylinder is supplied to the cylinder portion 7. It is configured to be supplied through a provided supply port (not shown). The piston 12 is provided with a concave portion 14 on the surface facing the inner pad 2, and a convex portion 15 formed on the back surface of the inner pad 2 is engaged with the concave portion 14, whereby the piston 12 with respect to the cylinder 10 is engaged. Rotation is blocked. Further, a dust boot 16 is provided between the bottom side of the piston 12 and the caliper body 6 to prevent foreign matter from entering the hydraulic chamber 13.

  An electric motor 38 is attached to the caliper body 6 through a housing 35. Further, the caliper body 6 and the housing 35 are provided with a speed reduction mechanism for increasing (decelerating) the rotational force of the electric motor 38 and a linear motion (hereinafter referred to as a linear motion and a linear motion as necessary). The ball ramp mechanism 28 (rotation / linear motion conversion mechanism) for propelling the piston 12 relative to the cylinder 10 by the obtained linear motion, and the piston according to the wear amount of the brake pads 2 and 3 And a pad wear adjusting mechanism 17 for adjusting the position of the 12 with respect to the cylinder 10.

  The pad wear adjustment mechanism 17 has an adjustment nut 18 and a push rod 19. The adjustment nut 18 has a friction surface 21 that is rotatably fitted to the piston 12 and frictionally engaged with a tapered friction surface 20 formed on the piston 12. The friction surface 21 is configured to be pressed against the friction surface 20 by a disc spring 22 and a thrust bearing 23 provided on the flange portion on the ball ramp mechanism 28 side. The tip end of the adjustment nut 18 (on the inner bottom side of the piston 12) is fitted in an airtight manner so as to be movable in a space 24 formed in the inner bottom of the piston 12, and the space 24 includes the passage 25 and the dust boot 16. It communicates with the atmosphere via. Further, the disc spring 22 is prevented from coming off from the piston 12 (moving in the right direction in FIG. 1) by a retaining ring fitted in an annular groove formed on the inner wall of the piston 12.

  One end of the push rod 19 is screwed into the screw hole of the adjustment nut 18, and the other end of the flange shape is guided in the axial direction of the cylinder 10 by a retainer 26 fixed to the cylinder 10, and around the axis thereof. Is prevented from rotating. The other end of the push rod 19 is urged toward the bottom side (right side in FIG. 1) of the cylinder 10 by the spring force of the coil spring 27, so that the thrust washer 30 is applied to the rotation linear plate 29 of the ball ramp mechanism 28. It is pressed through. The pad wear adjusting mechanism 17 is capable of rotating / linear motion conversion between the adjusting nut 18 and the push rod 19 by connecting the adjusting nut 18 and the push rod 19 with multiple threads. A predetermined gap, a so-called built-in clearance, is set between the threads of the multi-threaded screw. As a result, the adjustment nut 18 and the push rod 19 can move relative to each other by the built-in clearance, and the piston 12 slides when hydraulic pressure is applied to the hydraulic chamber 13. . The spring force of the coil spring 27 is set larger than the spring force of the disc spring 22.

  The ball ramp mechanism 28 is supported by a rotary linear plate 29 that is movable in the axial direction (left-right direction in FIG. 1) with respect to the cylinder 10 and that is rotatably supported around the axis, and the bottom wall 9 of the cylinder 10. And a fixed plate 32 that is prevented from rotating about its axis by a pin 31. The rotary linear motion plate 29 and the fixed plate 32 have a plurality of (three in this embodiment) ball grooves 29A and 32A that are formed so as to be opposed to the opposing surfaces. Between the ball grooves 29A and 32A facing each other between the plate 29 and the fixed plate 32, balls 33 each made of a steel ball are incorporated. With this configuration, when the rotary translation plate 29 is rotated about the axis with respect to the fixed plate 32, the balls 33 roll between the opposing ball grooves 29 </ b> A and 32 </ b> A. It is moved in the axial direction while rotating around the axis. In addition, the ball grooves 29A and 32A of the rotation / linear motion plate 29 and the fixed plate 32 can be configured by changing the inclination in addition to having a constant inclination.

  The disc brake 1 has a parking brake mechanism 34 configured in a housing 35 on the bottom side (right side in FIG. 1) of the hydraulic chamber 13 of the caliper 4. The parking brake mechanism 34 includes a rotation restricting mechanism 34 </ b> A, and the above-described reduction mechanism configured by a planetary gear mechanism 36 and a spur multi-stage mechanism 37. In the parking brake mechanism 34, a drive shaft 39 connected to the rotary translation plate 29 of the ball ramp mechanism 28 extends through the bottom wall 9 of the hydraulic chamber 13 into the housing 35, and the tip of the drive shaft 39 The second reduction gear 43 of the flat-tooth multi-stage mechanism 37 is attached. The hydraulic chamber 13 and the housing 35 are sealed with a seal member 40 provided on the bottom wall 9. Further, the second reduction gear 43 is prevented from moving in the axial direction with respect to the drive shaft 39 by a retaining ring 83 attached to the drive shaft 39.

  The planetary gear mechanism 36 includes a sun gear 44 fixed to the shaft 58 of the electric motor 38, a plurality (three in this embodiment) of planetary gears 45 meshed with the sun gear 44, and each planetary gear 45. And a carrier 41 (first shaft portion) that cantilever-supports each planetary gear 45 rotatably by each pin 47 (support portion). The internal gear 46 is pivotally supported by an outer peripheral surface of a boss 35B formed on the housing 35 so as to be rotatable about an axis, and is moved in the axial direction by a washer 49 fixed to an outer peripheral surface of a holder 85 described later. Movement is blocked.

  The carrier 41 is formed in a shape in which a disc-shaped portion 41A and a shaft portion 41B disposed on one surface side of the disc-shaped portion 41A are integrated, and a part of the outer periphery of the disc-shaped portion 41A will be described later. Ratchet teeth 57 with which the claw portion 55 of the lever 54 can be engaged are formed, and each pin 47 that cantileverably supports the planetary gear 45 is press-fitted between the center portion and the outer peripheral edge of the disc-like portion 41A. Pin holes 41C, which are through holes to be fixed, are formed at equal intervals (120 ° in this embodiment) along the circumferential direction. Further, on the surface opposite to the shaft portion 41B in the central portion of the disc-shaped portion 41A, there are a recess 41D into which a distal end portion of a holder 85 described later is inserted, and a plurality of grooves 82 extending radially from the recess 41D (this embodiment) 3) in the form. The shaft portion 41B of the carrier 41 has a small gear 41E formed on the outer peripheral side and a fixing hole 41F positioned on the central axis of the carrier 41 on the inner peripheral side. A pin 84 is press-fitted and fixed in the fixing hole 41F. One end (right end in FIG. 1) of the pin 84 is rotatably supported by the recess 61 of the cover 61 attached to the housing 35, and the other end (electric motor 38 side) is the sun gear 44 and the electric motor 38. Is fixed by press-fitting into a fixing hole 85 </ b> C formed at the tip of a holder 85 (see also FIG. 3) provided so as to surround the shaft 58. The holder 85 has a rear end portion 85B (second shaft portion) having an annular shape disposed on the opposite side of the carrier 41 (first shaft portion) with respect to the plurality of planetary gears 45. The rear end 85B is rotatably supported by the caliper body 6, more specifically, by the inner peripheral surface of a boss 35B formed in the housing 35. Further, the holder 85 extends from the rear end portion 85B toward the carrier 41 in the axial direction (right direction in FIG. 1) beyond the sun gear 44, and then extends toward the pin 84 via the R portion ( In this embodiment, it has three ribs 85A (crosslinked portion). A step portion 85D for positioning the washer 49 is formed on the outer peripheral side of the rear end portion 85B.

  As shown in FIG. 3, the three ribs 85 </ b> A each have a predetermined width and are provided at the rear end portion 85 </ b> B of the holder 85 at an angular phase of 120 ° in the circumferential direction. Further, the three ribs 85A extend from the rear end portion 85B and finally gather to form an annular tip portion. Then, the tip of the holder 85 (which can also be called the tip of the rib 85A) is inserted into the concave portion 41D of the carrier 41 and press-fitted and fixed to the pin 84, whereby the carrier 41 (first shaft portion). ) And the rear end portion 85B (second shaft portion) of the holder 85 are integrally coupled.

  Here, as shown in FIG. 4, the ribs 85 </ b> A extend so as to pass between the adjacent planetary gears 45, so that the holder 85 does not interfere with the planetary gears 45. Further, the holder 85 is prevented from moving in the axial direction by interposing the washer 49 described above between the end face of the boss 35 </ b> B of the housing 35 and each planetary gear 45. Further, as shown in FIG. 5, the holder 85 has a portion extending toward the pin 84 via the R portion of each rib 85 </ b> A (a portion extending perpendicular to the axis of the holder 85) in each groove of the carrier 41. By being engaged with 82, rotation about the axis with respect to the carrier 41 is prevented. In addition, with the pins 84 and the pins 47 fixed to the carrier 41 and the planetary gears 45 fitted to the pins 47, the holder 85 incorporating the washer 49 is fixed to the pins 84, so that the carrier assembly A is fixed. The electric disk brake 1 can be easily manufactured by assembling the carrier assembly A into the caliper body 6, more specifically, the boss 35 </ b> B formed in the housing 35.

  As shown in FIG. 5, the rotation restricting mechanisms 34 </ b> A are each formed in a teardrop shape and are provided to project from the outer edge portion of one side surface of the internal gear 46 (the right side in FIG. 1, that is, the side surface on the carrier 41 side). Provided at a predetermined position of the housing 35, a first convex portion 51 and a second convex portion 52, a lever 54 rotatably supported around the fixing pin 53 by a fixing pin 53 fixed at a predetermined position of the housing 35. And a coil spring 56 set to a predetermined set load for urging the lever 54 around the fixing pin 53 in the clockwise direction in FIG. The lever 54 has a claw portion 55 formed on the extension of the coil spring 56 (lower side in FIG. 5).

  The rotation restricting mechanism 34A has the internal gear 46 in FIG. 6 (A) in a state where both the first convex portion 51 and the second convex portion 52 shown in FIG. 6 (A) are not in contact with the lever 54. When the first convex portion 51 contacts the claw portion 55 by rotating clockwise, the lever 54 rotates counterclockwise around the fixing pin 53 so that the claw portion 55 contacts the carrier 41. The On the other hand, when the internal gear 46 rotates counterclockwise and the second convex portion 52 contacts the claw portion 55, the lever 54 rotates clockwise and the claw portion 55 contacts the restricting portion 35 </ b> A of the housing 35. Configured to touch.

  The rotation restricting mechanism 34A is configured to include the ratchet teeth 57 of the carrier 41 described above, and the engagement between the claw portions 55 of the lever 54 and the ratchet teeth 57 causes the carrier 41 to rotate clockwise (return of the piston 12). The rotation corresponding to the direction is regulated (see FIG. 9A). On the other hand, in the counterclockwise rotation, the claw portion 55 is pressed by the ratchet teeth 57 and the lever 54 is rotated clockwise around the fixing pin 53 according to the profile of the ratchet teeth 57 (the ratchet teeth 57 are By pushing up the claw portion 55 and getting over it (see FIG. 10A), the rotation is not restricted.

  As shown in FIG. 1, the spur multi-stage mechanism 37 includes a first reduction gear 60 in which a large gear 60A and a small gear 60B meshing with the small gear 41B of the carrier 41 are integrally formed, and the first reduction gear. And a second reduction gear 43 having a large gear 43A that meshes with the 60 small gears 60B. The first reduction gear 60 is rotatably supported by a shaft 62 having one end fixed to the cover 61 and the other end fixed to the housing 35. The second reduction gear 43 and the drive shaft 39 are spline-coupled to prevent relative rotation around the axis.

  1 is an electronic control unit that controls the electric motor 38, and reference numeral 71 is a parking switch that outputs a parking brake operation / release signal to the electronic control unit 70.

  Next, the operation of this embodiment will be described. First, the action at the time of braking of the disc brake 1 as a hydraulic brake will be described. When the driver depresses the brake pedal, a hydraulic pressure (working hydraulic pressure) corresponding to the depressing force of the brake pedal is supplied from a master cylinder (not shown) to the hydraulic pressure chamber 13 in the caliper 4 via a hydraulic pressure circuit. As a result, the piston 12 moves forward (moves leftward in FIG. 1) while bending the piston seal 11, and the inner pad 2 is pressed against the disc rotor 1A. The reaction force causes the caliper 4 to move relative to the carrier 5 as shown in FIG. The outer pad 3 attached to the claw portion 8 is pressed against the disc rotor 1A. As a result, the disc rotor 1 is sandwiched between the pair of brake pads 2 and 3 to generate a braking force.

  When the driver releases the brake pedal, the supply of fluid pressure from the master cylinder is interrupted, and the fluid pressure in the fluid pressure chamber 13 decreases. Thereby, the piston 12 is returned to the original position by the elasticity of the piston seal 11, and as a result, the braking force is released. When the movement amount of the piston 12 increases with wear of the brake pads 2 and 3, slip occurs between the piston 12 and the piston seal 11, thereby moving the original position of the piston 12 and adjusting the pad clearance to be constant. . Note that the detailed operation of the pad wear adjusting mechanism 17 is a well-known technique for those skilled in the art, and a description thereof will be omitted here.

  Next, the operation of the parking brake mechanism 34 will be described. FIG. 6A schematically illustrates the release state of the parking brake, that is, the state in which the parking brake is released, and FIGS. 6B to 11B are respectively in the state of (A). The position of the corresponding ball 33 with respect to the ball grooves 29A and 32A is shown. When the parking switch 71 is operated and the parking brake is applied in the released state of the parking brake shown in FIG. 6 (A), the electric motor 38 is operated based on the control of the electronic control unit 70. The mechanism 36 and the spur multi-stage mechanism 37 are driven, and the carrier 41 is given a torque that rotates around the pin 84 in the counterclockwise direction in FIG. In this state, the ball ramp mechanism 28 is prevented from rotating by the spring force of the coil spring 27 because the rotation of the rotary linear motion plate 29 around the axis is suppressed. As a result, the reaction force of the torque applied to the carrier 41 is input to the planetary gear mechanism 36 via the spur multi-stage mechanism 37, whereby the internal gear 46 is subjected to the reaction force of the carrier 41 in FIG. Rotate clockwise in (A).

  7A, when the first convex portion 51 of the internal gear 46 comes into contact with the claw portion 55 of the lever 54, the torque that drives the ball ramp mechanism 28 causes the lever 54 to be fixed to the fixing pin 53. The internal gear 46 does not rotate because it is set to be smaller than the torque required to rotate around. As a result, as shown in FIG. 8A, the carrier 41 rotates counterclockwise in FIG. 8A. When the rotation of the electric motor 38 is converted into a linear motion by the ball ramp mechanism 28 (rotation / linear motion conversion mechanism) and the piston 12 is propelled, the aforementioned braking force is generated.

  Here, when the torque required to rotate the lever 54 around the fixed pin 53 and the torque required to rotate the ball ramp mechanism 28 forward (rotation when propelling the piston 12) are compared, the lever The torque for rotating the ball ramp mechanism 28 is set to be larger than the torque for rotating 54 around the fixed pin 53. Accordingly, the carrier 41 rotates counterclockwise in FIG. 8A while the ratchet teeth 57 push up the lever 54. When the required braking force is obtained, the energization of the electric motor 38 is reduced under the control of the electronic control unit 70, and the ball ramp mechanism 28 rotates reversely to the forward rotation by the reaction force of the braking force.

  As a result, the carrier 41 first rotates in the clockwise direction in FIG. 8A, but since the torque in the clockwise direction in FIG. 8A is also applied to the internal gear 46, FIG. As shown in FIG. 9A, when the carrier 41 rotates to a position where the claw portion 55 of the lever 54 enters the trough portion 57A of the ratchet teeth 57, the claw portion 55 of the lever 54 as shown in FIG. And the ratchet teeth 57 are meshed. As a result, the carrier 41 is prevented from rotating clockwise in FIG. 9A, and the braking force of the disc brake 1 is maintained.

  In this state, when the parking switch 71 is operated and the application of the parking brake is released, the electric motor 38 is operated based on the control of the electronic control unit 70, whereby the planetary gear mechanism 36 and the spur multi-stage mechanism 37 are operated. The carrier 41 is driven, and a torque that rotates around the pin 84 in the clockwise direction in FIG. In the state shown in FIG. 9A, since the claw portion 55 of the lever 54 and the ratchet teeth 57 are engaged, the carrier 41 is prevented from rotating in the clockwise direction in FIG. 9A. Does not rotate.

  On the other hand, the internal gear 46 rotates counterclockwise in FIG. 9A due to the reaction force of the torque applied to the carrier 41, and the second convex portion 52 contacts the claw portion 55 of the lever 54. As a result, the lever 54 rotates around the fixing pin 53 in the clockwise direction in FIG. 9A, and as shown in FIG. 10A, the engagement between the claw portion 55 of the lever 54 and the ratchet teeth 57 occurs. Canceled. As a result, the carrier 41 rotates counterclockwise in FIG. 10A, and this rotation is transmitted to the ball ramp mechanism 28 via the flat tooth multi-stage mechanism 37, and the ball ramp mechanism 28 is transferred to FIG. Returning to the initial position shown, the release of the parking brake, that is, the release of the parking brake is completed.

This embodiment has the following effects.
According to this embodiment, a part corresponding to the carrier of the planetary gear mechanism (reduction mechanism) in the disc brake of the prior art is divided into two parts of the carrier 41 and the holder 85 by dividing the part in the axial direction of the carrier. 41 (first shaft portion) and the holder 85 are connected only by pins 84 arranged on a common axis, so that, for example, each pin 47 (support portion) that supports each planetary gear 2 When compared with a disc brake that employs a speed reducer with both planetary gears that join two parts, the coaxiality of the planetary gear mechanism 36 can be easily ensured. Here, in the planetary gear mechanism 36 of the present embodiment, the positional accuracy is required because the coaxiality between the rear end portion 85B of the holder 85 and the fixing hole 85C, each pin 47 of the carrier 41, and the fixing hole 41F. Therefore, it is possible to incorporate the planetary gear mechanism 36 into the electric disc brake 1 with a finishing process in a relatively small number of locations. Therefore, productivity can be improved and an increase in manufacturing cost can be suppressed.

Further, according to the present embodiment, the carrier 41, the holder 85, and the planetary gear constituting the planetary gear mechanism 36 can be sub-assembled to form the carrier assembly A, and the assembly is facilitated. The (assembly) process can be streamlined.
Further, according to the present embodiment, the tip end portion of the holder 85 (which can also be referred to as the tip end portion of the rib 85A) is inserted into the concave portion 41A of the carrier 41, and each rib 85A (crosslinking portion) of the holder 85 is inserted into the carrier. 41, the holder 85 is reliably prevented from rotating with respect to the carrier 41 even if the press-fit fixing force of the pin 84 is insufficient, and each rib 85A of the holder 85 is The reliability of the device can be ensured without interfering with the planetary gear 45.
Further, according to the present embodiment, the carrier assembly A has one end (the carrier 41 side) supported by the cover 61 and the other end (the holder 85 side, more specifically, the rear end portion 85B [second shaft portion]). Since both ends are supported (both ends supported) by the housing 35, even if the reaction force (radial load) from the first reduction gear 60 and the rotation restricting mechanism 34A is input to the carrier component, the shaft Without tilting, it is possible to ensure basic performance such as operating sound and efficiency, and the reliability of the rotation restricting mechanism 34A (parking brake mechanism 34). In particular, when the ratchet teeth 57 are formed on the carrier 41 as in the disc brake 1 of the present embodiment, a radial load acts on the carrier 41 when the ratchet teeth 57 are engaged with the claw portions 55. Rigidity is ensured by adopting a double-end support structure for the part.

In the present embodiment, the ball ramp mechanism 28 is employed as the rotation / linear motion conversion mechanism, and the pad wear adjustment mechanism 17 is combined with this to constitute the disc brake 1. However, the ball ramp mechanism 28 and the pad wear adjustment mechanism are configured. Instead of 17, for example, a high-efficiency continuous screw such as a ball screw mechanism can be used.
Further, in the case of using a sliding screw having no reverse operability represented by a triangular screw, the rotation restricting mechanism 34A becomes unnecessary by fixing the internal gear 46 to the housing 35. In this case, manufacturing at a lower cost is possible.

1 disc brake, 2 inner pad (brake pad), 3 outer pad (brake pad), 6 caliper body, 10 cylinder, 12 piston (pressing member), 28 ball ramp mechanism (rotation / linear motion conversion mechanism), 34 parking brake mechanism 36 planetary gear mechanism (reduction mechanism), 37 spur multi-stage mechanism (reduction mechanism), 38 electric motor, 41 carrier (first shaft), 44 sun gear, 45 planetary gear, 46 internal gear, 47 pin (support) Part), 85 holder, 85A rib (bridging part), 85B rear end part of holder (second shaft part)

Claims (1)

A pressing member provided in the cylinder of the caliper main body for pressing the brake pad against the disc rotor, an electric motor attached to the caliper main body, a reduction mechanism for increasing the rotational force of the electric motor, and an increase in force by the reduction mechanism A rotation / linear motion conversion mechanism that converts rotational force into linear motion, and the pressing member is propelled by the linear motion obtained by the rotation / linear motion conversion mechanism, and the propelled pressing member is held at the parking brake position. A disc brake having a parking brake mechanism,
The deceleration mechanism is
A sun gear to which rotational force from the electric motor is input / output, a plurality of planetary gears revolving around the rotation axis of the sun gear, an internal gear meshed with each planetary gear, and each planetary gear And a carrier member to which the rotational force from the electric motor is input / output by rotating with the revolution of each planetary gear.
The carrier member is
A first shaft portion axially supported by the caliper body and positioned on one side in the axial direction with respect to the plurality of planetary gears; A second shaft portion that is pivotally supported by the caliper body, a support portion that rotatably supports the plurality of planetary gears on the first shaft portion only on one side in the axial direction, and a plurality of planetary gears. A bridging portion that extends through and connects the first shaft portion and the second shaft portion together;
A disc brake characterized by comprising:

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