KR20100039075A

KR20100039075A - Disk brake with the electronic parking brake system

Info

Publication number: KR20100039075A
Application number: KR1020080098289A
Authority: KR
Inventors: 송준규; 심동국
Original assignee: 주식회사 만도
Priority date: 2008-10-07
Filing date: 2008-10-07
Publication date: 2010-04-15

Abstract

The present invention discloses a disc brake with an electronic brake system that can reduce the size of the overall system and reduce the manufacturing cost. The disc brake having the electronic brake system includes a torque limiter provided on the operating shaft to limit the rotation of the operating shaft, and an overcurrent blocking device which cuts off the power when a predetermined power is applied to the actuator.

Description

Disk brake with the electronic parking brake system

The present invention relates to a disc brake having a parking function, and more particularly to a disc brake having a function of an electronic parking brake which can be controlled electronically by the operation of the actuator.

In general, a brake device includes a parking brake, usually referred to as a hand brake or a side brake, which keeps a vehicle stationary. However, such a parking brake has a problem that the driver is required to operate the parking lever at the time of parking or starting the operation, which is very troublesome to use, especially for women or the elderly who are weak in strength.

Therefore, in recent years, an electronic parking brake (EPB) system for electronically controlling the driving of the parking brake is used, and is mounted on a conventional disk brake to perform the function of the parking brake. The electronic parking brake system automatically operates to maintain the parking or stopping state of the car when the driver stops the vehicle manually or when there is a risk of the vehicle being pushed back when the hill is departed. will be. Here, the electronic parking brake system includes a cable puller type, a motor-on-caliper type, and a hydraulic parking brake type.

1 is a view illustrating a disc brake using a conventional electronic parking brake system. Here, the electronic parking brake system shown in FIG. 1 is a cable puller type.

When the user presses the parking button (not shown) for parking, the actuator 10 is rotated. As the actuator 10 rotates, the gears inside the gearbox assembly 20 also start to rotate, and the driven gear 21 also rotates accordingly. When the driven gear 21 rotates, the spindle 50 connected to the rotating shaft of the driven gear 21 also starts to rotate. The equalizer 60 is advanced toward the cable tension measuring sensor 51 by the rotation of the spindle 50, and thus the brake cables 61 and 62 are pulled to maintain the parking state. At the time of release, if the user presses the button, the above operation is reversed to release the parking state.

In addition, the electronic parking brake system includes a count sensor 12 that counts the number of rotations of the actuator 10 on the rotation shaft 11 of the actuator 10, and a cable tension measurement for measuring the magnitude of the force acting on the parking brake. The sensor 51 further includes an electronic control unit (ECU) 70 for controlling the electronic parking brake system as a whole. The cable tension measuring sensor 51 is a plate member 53 provided inside the box-shaped casing 52 and an elastic member 54 wrapping the outer circumference of the spindle 50 penetrating the casing 52. Is done.

In the electronic parking brake system, the number of revolutions of the actuator 10 detected through the count sensor 12 or the force detected by the cable tension measuring sensor 51 is transmitted to the electronic control unit 70, thereby providing the electronic control unit 70. Control is achieved.

However, in the disc brake equipped with the conventional electronic parking brake system, the size of the entire system is increased and the manufacturing cost is increased by installing the electronic control unit 70, the count sensor 12, the cable tension measuring sensor 51, and the like for control. There is a problem that rises.

Accordingly, an object of the present invention is to provide a disc brake having an electronic parking brake system which can reduce the size of the entire system and reduce the manufacturing cost.

Disc brake equipped with the electronic parking brake system of the present invention to achieve the above object; A housing forming an appearance; An actuator mounted on one side of the housing to enable forward rotation and reverse rotation; A gearbox assembly having gears for reducing the rotational force generated by the actuator; A driven gear provided inside the gearbox assembly to transmit a reduced rotational force; A spiral threaded spindle connected to the driven gear; A screw nut having a coupling hole screwed to the spindle; An equalizer through which the spindle passes and into which the screw nut is rotatably inserted; A brake cable having a fastening piece at a front end thereof so as to be connected to both sides of the equalizer, and a second end thereof connected to each wheel brake device; It is characterized in that it comprises a torque limiter provided on the spindle to limit the rotation of the spindle when a braking force of a predetermined magnitude or more is transmitted from the spindle.

The apparatus may further include an overcurrent blocking device to cut off the power when a predetermined power or more is applied to the actuator.

In addition, the actuator is characterized in that it is provided with a step motor capable of forward rotation and reverse rotation.

As described above, the disc brake with the electronic parking brake system according to the present invention can control the electronic parking brake system through a torque limiter for limiting the rotation of the operating shaft, and an overcurrent blocking device for shutting off the power applied to the actuator. Therefore, the overall system size can be reduced and manufacturing cost can be reduced.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment according to the technical idea of the disc brake having an electronic parking brake system according to the present invention as described above.

As shown in Fig. 2, the housing 1 is a rectangular box, which is mounted or installed on the vehicle body or the frame of the vehicle. Two through holes 2 and 3 through which the brake cables 61 and 62 pass are formed in the front wall of the housing 1.

On the rear wall of the housing 1, an actuator 10 for generating power for operating the brake is installed on one side of the housing 1. The actuator 10 may be provided with a step motor capable of forward rotation and reverse rotation. The actuator 20 is connected to a parking button (not shown) operated by the driver.

The gearbox assembly 20 to which power generated from the actuator 10 is transmitted is connected to the inside of the housing 1. The gearbox assembly 20 serves to reduce the speed due to the power generated from the actuator 10. A plurality of gears are provided inside the gearbox assembly 20 to reduce the rotational force transmitted from the actuator 10. In addition, a driven gear 21 for interlocking a transmission force transmitted from the actuator 10 to the outside is installed in the gearbox assembly 20. This driven gear 21 is axially coupled to the spindle 50.

The spindle 50 is formed in a rod shape having a constant length, and spirals are formed continuously in the longitudinal direction thereof. The screw nut 63 is screwed to the spindle 50. That is, the spindle 50 is inserted into the screw nut 63, and a coupling hole (not shown) having spirals coupled to the spiral of the spindle 50 is formed in the screw nut 63. According to the coupling structure as described above, when the spindle 50 rotates, the screw nut 63 is moved forward or backward due to the interaction of the coupling hole of the screw and the screw nut 63 in the rotation direction thereof. This is due to the forward and reverse rotation of the actuator 10.

Meanwhile, brake cables 61 and 62 are connected to the equalizer 60. A circumferential fastening piece (not shown) is integrally formed at the tip of each brake cable 61, 62. The fastening piece (not shown) is coupled to the inside of the insertion hole 64 formed on both sides of the equalizer 60, when the equalizer 60 is pulled, the brake cables 61 and 62 connected to the equalizer 60 are eventually pulled out. The parking brake device provided in each wheel is operated to maintain each wheel in a braking state, thereby maintaining the parking state of the vehicle.

In addition, the electronic parking brake system of the present invention includes a mechanical torque limiter 80 to prevent the parking force from increasing further when an appropriate parking force is applied. And, with the over-current blocking element 90, as the parking force increases, the electric current to cut off before the excessive current reaches the excessive parking force.

The torque limiter 80 is provided on the spindle 50 as shown, and serves to limit the rotation of the spindle 50 mechanically so that a braking force of a predetermined magnitude or more cannot be transmitted through the spindle 50.

The overcurrent blocking device 90 is provided at the tip of the actuator 10 to continuously apply power to the actuator 10 to automatically cut off the power applied to the actuator 10 when the current amount is increased by a certain amount or more, thereby preventing excessive braking force. It serves to prevent transmission. Here, the overcurrent blocking device 90 of the present invention is connected to an electronic stability program (ESP) not shown and is controlled.

That is, when the operation button (not shown) inside the driver's seat is operated, the power is continuously supplied to the electronic parking brake system, and if the parking force is increased by the continuous power supply, the torque limiter 80 prevents the parking force increase when the parking force is appropriate. In addition, the overcurrent blocking device 90 automatically cuts off the power of the electronic parking brake system.

Therefore, the present invention can be controlled without the installation of an expensive electronic control unit, a count sensor, a cable tension measuring sensor, such as a disk brake having a conventional electronic parking brake system, it is possible to reduce the size of the entire system than the conventional The manufacturing cost can be reduced.

In the above, the present invention has been illustrated and described with respect to certain preferred embodiments. However, the present invention is not limited only to the above-described embodiments, and those skilled in the art to which the present invention pertains can variously change without departing from the gist of the technical idea of the present invention described in the claims below. Could be done.

1 is a cross-sectional view of a disc brake with a conventional electronic parking brake system.

2 is a cross-sectional view of a disc brake with an electronic parking brake system according to the present invention.

* Description of the symbols for the main parts of the drawings *

10: actuator 20: gearbox assembly

50: spindle 60: equalizer

80: torque limiter 90: overcurrent blocking element

Claims

A housing forming an appearance; An actuator mounted on one side of the housing to enable forward rotation and reverse rotation; A gearbox assembly having gears for reducing the rotational force generated by the actuator; A driven gear provided inside the gearbox assembly to transmit a reduced rotational force; A spiral threaded spindle connected to the driven gear; A screw nut having a coupling hole screwed to the spindle; An equalizer through which the spindle passes and into which the screw nut is rotatably inserted; A brake cable having a fastening piece at a front end thereof so as to be connected to both sides of the equalizer, and a second end thereof connected to each wheel brake device; And a torque limiter provided on the spindle to limit rotation of the spindle when a braking force of a predetermined magnitude or more is transmitted from the spindle.

The method of claim 1,

The disk brake having an electronic parking brake system, characterized in that it further comprises an over-current blocking element to cut off the power when a predetermined or more power is applied to the actuator.

The method according to claim 1 or 2,

The actuator is a disc brake with an electronic parking brake system, characterized in that provided with a step motor capable of forward and reverse rotation.