KR101407469B1 - Disk Brake having parking function - Google Patents

Abstract

Disclosed in the present invention is a disk brake with a parking function capable of enabling easy operation of a parking system by operating the parking system using an electric motor. The existing disk brake with a parking function occupies much space for installation, causing interference with other neighboring components and being installable only in limited kinds of vehicles. The disk brake with a parking function given in the present invention is provided to resolve the problems described above. A three-stage planetary gear structure is integrated into an installation space for the existing two-stage planetary gear so that the deceleration rate can be effectively increased and the axial length can be reduced. Also, as additional installation space for an electric motor is not necessary by placing the electric motor on the same axis with a piston, the present invention is able to reduce the installation space and accordingly prevent interference with other neighboring components, thereby being applicable to various kinds of vehicles.

Description

Disc Brake having parking function "

The present invention relates to a disc brake having a parking function, and more particularly, to a disc brake having a parking function capable of implementing a parking function by the operation of an electric motor.

Generally, a disc brake having a parking function for parking a vehicle includes first and second friction pads disposed on both sides of a disc rotating together with the wheel, a caliper housing and a piston for pressing the friction pads, And a parking lot capable of braking the disc for the purpose of parking the vehicle. The parking lot is provided with an operating shaft rotatably installed in the cylinder of the caliper housing, a pressurizing sleeve provided inside the piston for advancing or retreating by rotation of the operating shaft and releasing the pressure, an electric motor for rotating the operating shaft, And a plurality of planetary gear units that are provided between the planetary gear unit and the operation shaft to decelerate the rotational speed of the electric motor and transmit a large rotational force.

The disk brake with such a parking function has a tendency of rapid increase in demand due to the acceleration of the automobile electronics. However, the disk brake electric motor having the parking function of the related art functions as the planetary gear unit, the operating shaft, the pressurizing sleeve, When the electric motor is arranged in parallel with the axis of the operating shaft, the space required for disposing the electric motor is separately required, and the space occupied by the electric motor is increased .

Therefore, when the vehicle is mounted on the vehicle, interference with other parts such as a wheel or a suspension of the vehicle occurs.

Korean Registered Patent No. 10-2006-0132676 (2008. 4. 2. Announcement)

SUMMARY OF THE INVENTION The present invention has been devised to solve the problems as described above, and it is an object of the present invention to reduce the mounting space by arranging a three-stage planetary gear structure in a mounting space of a conventional two- And to provide a disc brake having a parking function that can be mounted on various vehicles by reducing space constraints caused by interference with other components when the vehicle is mounted on the vehicle.

In order to achieve the above object, according to an embodiment of the present invention, there is provided a caliper housing having a piston for pressing a friction pad for braking a disk and a cylinder portion for movably accommodating the piston, Wherein the electric motor is used as a power source for driving the electric motor and an operation shaft for transmitting the power to the piston by converting the rotary motion of the electric motor into a translational motion, A disk brake having a parking function,

Wherein the speed reducer includes a plurality of planetary gear units,

Each of the planetary gear units is disposed in series with an electric motor for generating rotational force,

The planetary gear unit coupled with the electric motor may be provided with an input / output gear that receives a rotational force and outputs a rotational force to a neighboring planetary gear unit.

Wherein said plurality of planetary gear units are constituted by a three-stage planetary gear structure,

A first planetary gear unit that receives and decelerates a rotational force from the motor;

A second planetary gear unit connected to the first planetary gear unit; And

And a third planetary gear unit connected to the second planetary gear unit,

The third planetary gear unit may transmit a rotational force to the operating shaft.

The first planetary gear unit

A first ring gear connected to the electric motor and receiving power;

A plurality of first planetary gears that are in contact with the first ring gear and each have a shaft hole formed at the center thereof;

A first carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of first planetary gears;

And a first input / output gear integrally formed with the first carrier and coaxially rotating at a central portion of the first carrier,

The second planetary gear unit

A plurality of second planetary gears meshing with the first input / output gear and each having a shaft hole formed at the center thereof;

A main portion having a large diameter and provided with a gear train only on the inner circumferential surface, and a subsidiary portion having a small diameter and having gear trains on both the inner circumferential surface and the outer circumferential surface, A second ring gear fixedly secured;

A second carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of second planetary gears;

And a second input / output gear formed integrally with the second carrier and coaxially rotating at a central portion of the second carrier,

The third planetary gear unit includes:

A plurality of third planetary gears meshing with the second input / output gear and being in contact with the main portion of the second ring gear and having shaft holes formed at the center thereof;

A third carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of third planetary gears;

And a third input / output gear which is formed integrally with the third carrier and coaxially rotates at the center of the third carrier.

The first, second, and third input / output gears are provided at the centers of the working shaft side surfaces of the first, second, and third carriers, and are coaxial with the first, second, and third carriers to input and output power.

The first ring gear may include a gear train on an inner circumferential surface thereof, one side thereof being open, and the other side thereof being open only at a portion thereof which engages with the rotation axis gear train of the electric motor, so as to receive the rotational force of the electric motor.

Wherein the main portion of the second ring gear is adjacent to the third planetary gear unit and is in contact with the plurality of third planetary gears,

Wherein the auxiliary portion of the second ring gear is provided adjacent to the first planetary gear unit so that the gear train on the outer peripheral surface is in contact with the plurality of first planetary gears and the gear train on the inner peripheral surface is in contact with the plurality of second planetary gears .

The disc brake having the parking function according to the embodiment of the present invention can effectively increase the reduction ratio while occupying a small space by integrating and applying the three-stage planetary gear structure to the mounting space of the two-stage planetary gear, The direction length is reduced and the electric motor is arranged coaxially with the operating shaft, so that a separate space for the electric motor is not required. As a result, the mounting space is reduced, So that it can be applied to various kinds of vehicles.

1 is a cross-sectional view schematically showing a disc brake having a parking function according to an embodiment of the present invention.
2 is an enlarged cross-sectional view of a three-stage planetary gear structure of a disc brake having a parking function according to an embodiment of the present invention.
FIGS. 3A and 3B are exploded perspective views showing an assembled state of a three-stage planetary gear structure of a disc brake having a parking function according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are provided by way of example so that those skilled in the art will be able to fully understand the spirit of the present invention. The present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, and the like of the components may be exaggerated for the sake of convenience. Like reference numerals designate like elements throughout the specification.

As shown in FIG. 1, a disc brake having a parking function according to an embodiment of the present invention includes first and second friction pads 11 and 12 disposed on both sides of a disc 1 rotating together with wheels, A caliper housing 13 and a piston 14 for pressurizing the friction pads 11, 12.

The caliper housing 13 includes a body portion 16 formed with a cylinder portion 15 for accommodating the piston 14 movably and a connecting portion 17 extending from the body portion 16 toward the opposite first friction pad 11 And a supporting portion 18 extending from the connecting portion 17 to support the back surface of the first friction pad 11. [ The body portion 16 is formed with an oil port 19 into which the brake oil flows so that oil pressure for braking can be applied to the inside of the cylinder portion 15. Oil is supplied between the outer surface of the piston 14 and the inner surface of the cylinder portion 15, A packing 20 for preventing leakage of the gas is installed.

This configuration is such that when the hydraulic pressure for braking is applied to the cylinder 15, the piston 14 advances toward the second friction pad 12 to press the second friction pad 12, So that the support portion 18 presses the first friction pad 11 to perform the braking of the disc 1. As shown in Fig.

The hydraulic pressure for braking may be hydraulic pressure generated from a master cylinder (not shown) of a conventional brake system, or may be a hydraulic pressure applied to a vehicle to which an anti-lock brake system (ABS) or a brake traction control system (BTCS) The hydraulic pressure generated by the operation of the hydraulic pump (not shown) for generating the hydraulic pressure can be used.

In addition, the disc brake of the present invention has a parking lot capable of braking the disc 1 for parking the vehicle. The parking lot is provided with an operating shaft 23 rotatably installed in the cylinder 15 of the caliper housing 13 and a piston 14 for pushing or releasing the piston 14 by advancing and retreating by the rotation of the operating shaft 23 An electric motor 25 for rotating the operation shaft 23 and an electric motor 25 are connected to the operation shaft 23 so that the rotational force of the electric motor 25 And includes a decelerator for decelerating the speed.

The operation shaft 23 has a support portion 23a rotatably supported at the rear end side of the cylinder portion 15 and a male thread portion 23b extending from the support portion 23a toward the inner center portion of the piston 14 by a predetermined length And a coupling groove 23c at the center so as to be coupled to the input / output gear provided at the central portion of the carrier of the final stage planetary gear unit, which extends in the opposite direction to the male screw portion 23b at the support portion 23a. The engaging groove 23c is provided in a structure that engages with the gear train of the carrier so that the operating shaft 23 and the carrier 54 do not rotate relative to each other.

The pressurizing sleeve 24 is formed in a cylindrical shape and has a female threaded portion 24a on the inner surface thereof to be engaged with the male threaded portion 23a of the operating shaft 23 so as to be able to move in the axial direction by rotation of the operating shaft 23 . Also, there is provided between the outer surface of the pressure sleeve (24) and the inner surface of the piston (14) tapered engagement surfaces (24b, 14a) in contact with each other. This configuration is such that the pressure sleeve 24 is advanced or retracted when the operating shaft 23 rotates in the forward or reverse direction and the pressure sleeve 24 presses the piston 14 so that braking can be performed.

The pressing sleeve 24 and the piston 14 can be kept in contact with each other at a position between the outer surface of the pressurizing sleeve 24 and the inner surface of the piston 14 so that the engaging surface 24b of the pressurizing sleeve 24 and the engaging surface 14a of the piston 14 are kept in contact with each other. And a gap adjusting spring 27 for pressing the pressing member 24 is provided. The outer peripheral portion is supported by the support ring 28 on the inner surface of the piston 14 and the inner peripheral portion is supported on the outer surface of the pressurizing sleeve 24 via the bearing 29. [ .

This is because when the piston 14 moves in the direction of the disc 1 due to wear of the friction pads 11 and 12 and a clearance is formed between the engagement surfaces 14a and 24b, 24 are pressed so that the contact of the engagement surfaces 14a, 24b can be maintained. That is, when braking is performed by hydraulic pressure, the operation shaft 23 does not rotate and the piston 14 advances. The piston 14 is moved toward the disk 1 due to wear of the friction pads 11, A clearance adjusting spring 27 moves the pressure sleeve 24 toward the piston 14 when a clearance is formed between the engagement surfaces 14a and 24b of the piston 14 and the pressure sleeve 24, 14a, 24b are kept in contact with each other and the clearance between the friction pads 11, 12 and the disc 1 can be adjusted.

When the gap adjustment is performed, the engagement surfaces 24a and 24b are spaced apart from each other and the operation shaft 23 is not rotated. Therefore, when the pressure sleeve 24 is pressed by the gap adjusting spring 27, And moves toward the piston 14 while rotating. The female screw portion 24a of the pressurizing sleeve 24 and the male screw portion 23b of the operating shaft 23 are formed by a plurality of screw threads so as to be tightened and loosened It is preferable to make it easy. The male threaded portion 23b of the operating rod 23 and the female threaded portion 24a of the pressurizing sleeve 24 are engaged with each other in a predetermined section that allows the movement of the piston 14 in the direction of releasing the brake when the hydraulic pressure for braking is released .

The cylinder portion 15 is provided with a support spring 31 for supporting the support portion 23a of the operation shaft 23 in order to restrict the axial movement of the operation shaft 23, And a cap-shaped spring support member 32 is provided. The spring support member 32 is fixed in the cylinder portion 15.

The electric motor 25 is powered by the operation of an operation switch provided on the driver's seat of the vehicle, and converts electrical energy into mechanical rotational kinetic energy. Fig. 2 is an enlarged cross-sectional view of a portion of the present invention, and Figs. 3a and 3b are exploded perspective views showing an assembly state of a three-stage planetary gear unit.

2, the casing 45 has a flange portion 45a formed with a bolt fastening hole so as to be bolted to the rear end of the caliper housing 13. As shown in Fig.

Generally, since the number of revolutions of the motor is inversely proportional to the torque, a device for amplifying the transmitted torque while decelerating the speed of the motor rotating at high speed needs to be separately provided. For this purpose, a speed reducer is provided between the electric motor 25 and the operation shaft 23.

Hereinafter, the configuration of the disc brake having the parking function according to the embodiment of the present invention will be described with reference to Figs. 2 and 3. Fig.

The present invention has a speed reducer in which a three-stage planetary gear structure is integrated in a space of a two-stage planetary gear structure, and an operating shaft (23) and an electric motor (25) are disposed coaxially to minimize a mounting space.

The reduction gear can increase the reduction ratio by continuously arranging the planetary gear structure in three stages. The reduction gear includes the first planetary gear unit, the second planetary gear unit, and the third planetary gear unit.

The first planetary gear unit includes a first ring gear (50) connected to the electric motor, a plurality of first planetary gears (52) in contact with the first ring gear (50) A fixed rod 51b is formed for each corresponding region so as to be inserted into a shaft hole formed in each of the plurality of first planetary gears 52. A first carrier 51 which rotates coaxially with the electric motor 25, And a first input / output gear 51a formed integrally with the first carrier 51 and coaxially rotated at the center of the first carrier 51.

The second planetary gear unit is provided with a plurality of second planetary gears 56 which are meshed with the first input / output gear 51a and have shaft holes formed at the center thereof, and two ring gears having different diameters A main portion 55a having a large diameter and provided with a gear train only on the inner circumferential surface thereof, a auxiliary portion 55b having a small diameter and having gear trains both on the inner circumferential surface and the outer circumferential surface, And a fixed rod 57b is formed for each corresponding region so as to be inserted into the shaft hole formed in each of the plurality of second planetary gears 56. A second rod And a second input / output gear 57a integrally formed with the carrier 57 and the second carrier 57 at the center of the second carrier 57 and rotating coaxially.

The third planetary gear unit is meshed with the second input / output gear (57a) and has a plurality of third planetary gears (57a, 57b) which are in contact with the main portion (55a) of the second ring gear (61b) is formed for each corresponding region to be inserted into a shaft hole formed in each of the plurality of third planetary gears (60) and the plurality of third planetary gears (60), and a third carrier And a third input / output gear 61a integrally formed with the third carrier 61 and coaxially rotated at the center of the third carrier 61. [

The first, second and third input / output gears 51a, 57a and 61a are located at the center of the side of the operating shaft 23 side of the first, second and third carriers 51, 57 and 61, 3 carriers 51, 57 and 61 so as to input and output power. The third input / output gear 61a serves to finally transmit the input power to the actuating shaft 23 and is coupled to the engaging groove 23c.

The first ring gear 50 of the first planetary gear unit is opened on one side but only the corresponding portion of the other side is opened in accordance with the shape of the gear train engaged with the rotation shaft of the electric motor 25, Receives the rotational force of the electric motor 25 directly.

The second ring gear 55 of the second planetary gear unit includes the main portion 55a and the auxiliary portion 55b and the main portion 55a of the second ring gear 55 has the diameter And the auxiliary portion 55b of the second ring gear 55 has a small diameter and is provided with a gear train for both the inner and outer circumferential surfaces. The inner circumferential surface is in contact with the plurality of second planetary gears (56), and the outer circumferential surface is circumscribed with the plurality of first planetary gears (52).

Accordingly, the first, second, and third planetary gears 52, 26, and 60 are engaged with the second ring gear 55 having a configuration in which two ring gears having different diameters are combined, The three-stage planetary gear unit can be integrated in the two-stage planetary gear-mounting space.

Hereinafter, the operation of the disc brake with the parking function according to the embodiment of the present invention will be described with reference to FIGS. 2 and 3. FIG.

When the driver operates the operation switch for parking, the electric motor 25 is rotated. The rotation of the electric motor 25 rotates the first ring gear 50 connected to the rotation shaft of the electric motor 25 and thereby generates the rotation of the first planetary gears 52, . The first input / output gear 51a integrally formed with the first carrier 51 and rotating coaxially with the electric motor 25 rotates together with the first carrier 51 to rotate the plurality of And transmits power to the second planetary gears (56). The second ring gear 55 is fixed so as not to rotate and the plurality of second planetary gears 56 rotate in contact with the inner peripheral surface of the auxiliary portion 55b of the second ring gear 55, (52) are circumscribed on the outer circumferential surface of the convex portion (55b) of the second ring gear (55) and rotated. The plurality of second planetary gears 56 rotating on the inner circumferential surface of the shaft portion 55b of the second ring gear 55 generate rotation of the second carrier 57 and are formed integrally with the second carrier 57 And transmits the rotational force to the second input / output gear 57a rotating coaxially with the electric motor 25. [ The plurality of third planetary gears 60 of the third planetary gear unit engaging with the second input / output gear 57a are rotated, and the third planetary gears 60, which are in contact with the inner peripheral surface gear train of the main portion 55a of the second ring gear 55 To the third carrier (61). The third input / output gear 61a, which is integrally formed with the third carrier 61 and configured to rotate coaxially with the third carrier 61, receives power in accordance with the rotation of the third carrier 61, The third input / output gear 61a coupled to the output shaft 61 outputs the power amplified to the operation shaft 23 at a large reduction ratio. When the operating shaft 23 rotates, the pressing sleeve 24 is moved in the axial direction, and the pressing sleeve 24 presses the piston 14 to perform braking.

After the braking is performed, the operation of the electric motor 25 is stopped. At this time, since the present invention has a large reduction ratio by the three-stage planetary gear unit, the reverse rotation of the operating shaft 23 is prevented. Therefore, the braking state is maintained as long as the electric motor 25 is not driven again.

When the driver releases the braking, the operation switch of the driver's seat is operated to release the braking. At this time, since the electric motor 25 rotates in the opposite direction of rotation and the operating shaft 23 rotates in the reverse direction at the same time, the pressurizing sleeve 24 releases the pressure of the piston 14 to release the braking.

The disk brake having the above-described parking function is configured such that the second ring gear 55 is constituted by the main portion 55a and the auxiliary portion 55b so that the plurality of planetary gears of the three- By fitting all the gears into the gear, the three-stage planetary gear structure can be integrated and applied to the mounting space of the conventional two-stage planetary gear, thereby reducing the mounting space.

In addition, when the electric motor 25 is connected in parallel with the operation shaft 23, a separate mounting space for disposing the electric motor 25 is required. However, referring to FIG. 4, It is possible to maximize the space utilization by disposing the motor 25 on the same line as the axis of the operating shaft 23 and the three-stage planetary gears, thereby eliminating the need for a separate mounting space for positioning the electric motor 25. [

As the mounting space is reduced, interference with peripheral components can be avoided, and mounting on various types of vehicles becomes easier.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

1: Disc 11, 12: Friction pad
13: caliper housing 14: piston
15: cylinder part 23: operating shaft
24: pressure sleeve 25: electric motor
45: casing 50: first ring gear
51: first carrier 51a: first input / output gear
52: first planetary gear 55: second ring gear
55a: main part 55b:
56: second ring gear 57: second carrier
57a: second input / output gear 60: third planetary gear
61: third carrier 61a: third input / output gear

Claims (6)

A caliper housing having a piston for pressing a friction pad for braking the disk and a cylinder portion for movably accommodating the piston; and an electric motor as a power source for generating the movement of the piston, And a decelerator that has an operation shaft for converting power to the piston to translational motion and transmitting power to the piston and transmitting the decelerated rotation speed of the electric motor to the operation shaft,
Wherein the speed reducer includes a plurality of planetary gear units,
Each of the planetary gear units is disposed in series with an electric motor for generating rotational force,
And an input / output gear for receiving a rotational force and outputting rotational force to a neighboring planetary gear unit, the planetary gear unit being coupled to the electric motor and being provided with a rotational force,
Wherein said plurality of planetary gear units are constituted by a three-stage planetary gear structure,
A first planetary gear unit that receives and decelerates a rotational force from the motor;
A second planetary gear unit connected to the first planetary gear unit; And
And a third planetary gear unit connected to the second planetary gear unit,
Wherein the first planetary gear unit includes:
A first ring gear connected to the electric motor and receiving power;
A plurality of first planetary gears that are in contact with the first ring gear and each have a shaft hole formed at the center thereof;
A first carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of first planetary gears;
And a first input / output gear integrally formed with the first carrier and coaxially rotating at a central portion of the first carrier,
Wherein the second planetary gear unit comprises:
A plurality of second planetary gears meshing with the first input / output gear and each having a shaft hole formed at the center thereof;
A main portion having a large diameter and provided with a gear train only on the inner circumferential surface, and a subsidiary portion having a small diameter and having gear trains on both the inner circumferential surface and the outer circumferential surface, A second ring gear fixedly secured;
A second carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of second planetary gears;
And a second input / output gear formed integrally with the second carrier and coaxially rotating at a central portion of the second carrier,
And the third planetary gear unit is connected to the second input / output gear to transmit rotational force to the operation shaft. delete The method of claim 1, further comprising:
The third planetary gear unit includes:
A plurality of third planetary gears meshing with the second input / output gear and being in contact with the main portion of the second ring gear and having shaft holes formed at the center thereof;
A third carrier rotatably coaxial with the electric motor and having fixed rods formed in corresponding regions to be inserted into the shaft holes formed in the plurality of third planetary gears;
And a third input / output gear formed integrally with the third carrier and coaxially rotating at a central portion of the third carrier. The method of claim 3,
The first, second and third input / output gears are provided at the center of the working shaft side surfaces of the first, second and third carriers and coaxially rotate with the first, second and third carriers to input and output power. . The method of claim 3,
Wherein the first ring gear is provided with a gear train on an inner circumferential surface thereof and one surface thereof is opened and the other surface thereof is opened only at a portion of the other gear which engages with the rotation axis gear train of the electric motor so as to receive the rotational force of the electric motor. The method of claim 3,
Wherein the main portion of the second ring gear is adjacent to the third planetary gear unit and is in contact with the plurality of third planetary gears,
Wherein the auxiliary portion of the second ring gear is provided adjacent to the first planetary gear unit, the gear train on the outer peripheral surface is in contact with the plurality of first planetary gears, and the gear train on the inner peripheral surface is in contact with the plurality of second planetary gears Disc brakes with parking.

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