KR101482270B1 - Electro Mechanical Brake System having gear engaging typed electro parking braking force - Google Patents

Abstract

When the EMB (Electro Mechanical Brake) of the present invention is braked by using the rotation of the reducer 3 through the actuator 2 that generates power under the control of the ECU 1, the non-self locking (NSL) The brakes are realized by moving the pads 9a and 9b toward the wheel disc D by the axial movement of the spindle 6 and by engaging the first and second gears 4 and 5 constituting the speed reducer 3, Since the switchgear 12 for blocking the backward movement of the solenoid 6 is provided together with the solenoid 11, the spindle 6 is pushed back when the solenoid 11 is switched off after the parking brake So that the solenoid 11 can restrain the speed reducer 3 and maintain the parking braking state.

Parking, electric brake, restraint position

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electric braking apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric brake apparatus, and more particularly to an electric brake apparatus having a parking brake function using gears.

Generally, a brake (brake system) is a braking device used for decelerating or stopping a traveling vehicle while maintaining a parking state.

These brakes are usually friction-type brakes that convert kinetic energy into heat energy by using frictional force and release it into the atmosphere, which causes the disc to rotate together with the wheel, Function.

However, since such a hydraulic brake is implemented in a manner that the pad is strongly urged toward the disk by using the hydraulic pressure during braking, the hydraulic brake is operated by the master cylinder which is operated through the booster for exercising the pedal operation force to generate the hydraulic pressure, A complicated configuration is required for various devices to control and assisting them. Further, there is a certain limit to the complexity of such a configuration and the reliability of the braking performance depending on the use of the hydraulic pressure, and the like.

As a result, EMB (Electro Mechanical Brake) which can simplify the structure that hydraulic brake does not have and enhance reliability of braking performance is used.

In addition, EPB (Electro Parking Brake), which is an electric parking function for parking braking, is added to the EMB. This EPB is a non-self locking type piston with high power transmission efficiency. , It is configured to implement the EPB using solenoid and ratchet shaped instruments to minimize the size and weight increase of the EMB.

However, if a solenoid and a ratchet structure are applied to the EPB function added to the EMB, the ratchet is engaged with the gear portion to maintain the braking force by normally switching the solenoid off during parking braking. This results in a certain resolution between the ratchet and the gear, which has a fundamental limitation in that it can not be corrected for the pad wear less than the resolution.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide an electronic parking brake (EPB), which is an electric parking function added to an electro mechanical brake using a motor driving force as a disc braking force, using a solenoid and a speed reducer- Self Locking type When the solenoid is turned off, the non-self locking type spindle engages with the decelerator so that the spindle does not fall off the pad, restraining rotation to maintain the braking force, The present invention is intended to make it possible to perform wear correction in any pad wear state since the resolution is not formed due to the limitation of the engagement position of the gear engaged with the speed reducer coupled to the type piston.

According to an aspect of the present invention, there is provided an electronic braking system comprising: an ECU for generating a control signal for braking together with measurement information on a vehicle running state when an electric brake apparatus senses a signal of an electronic pedal;

An actuator controlled by the ECU to generate power;

And a second gear rotating together with the first gear rotated together with the actuator;

A spindle rotated through the second gear to generate an axial force that pushes the inner pad toward the wheel disc;

A parking braking assy for restricting the throttle of a non-self locking (NSL) screw type spindle receiving a reaction force from a wheel disk using a solenoid switched off after parking brake;

A caliper provided inside the caliper body and having an inner / outer pad for pressurizing and braking the wheel disk;

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To this end, the spindle is composed of a screw shaft to which a second gear, which is a speed reducer, is fixedly rotated, and a screw nut which is axially moved according to the rotation direction of the screw shaft.

The parking brake assist includes a solenoid, a switchgear coupled to a rod axis of the solenoid, and a spring that is compressed by a switchgear which is moved toward the reducer through a rod shaft extending from the solenoid in an off state.

Further, the switchgear is allowed to rotate with respect to the solenoid.

According to the present invention, after the EMB (Electro-mechanical Brake) using the actuator driving force is switched to the solenoid off due to the parking brake by the wheel disc braking force, the solenoid is engaged with the decelerator side to form a non-self locking type spindle The parking brake can be maintained by restraining the parking brake, and the resolution can be eliminated by eliminating the limitation of the engagement position with respect to the gear that constitutes the reduction gear, so that the wear correction can be continuously made irrespective of the wear degree of the pad .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. The present invention is not limited to these embodiments.

1 is a configuration diagram of an electric braking apparatus having a parking braking function using gears according to the present invention. The electro brake (EMB), which is an electric braking apparatus of the present invention, And an actuator 2 that generates power under the control of the ECU 1. The speed reducer 3 rotates through the power of the actuator 2, And a spindle 6 for generating an axial movement in which the pads 9a and 9b are moved toward the wheel disc D by using a rotational force through the speed reducer 3. [

To this end, the ECU 1 receives vehicle position information via a yaw moment sensor mounted on the vehicle in addition to the input amount information of the operated electronic pedal, and implements the control required in braking.

The actuator (2) applies a motor.

The speed reducer 3 is composed of first and second gears 4 and 5 which are rotated together with each other. The second gear 5 is fixed to and rotates together with the actuator 2, (5) rotates the spindle (6).

The spindle 6 includes a screw shaft 7 to which the second gear 5 constituting the speed reducer 3 is fixedly rotated and a screw nut 7 to be axially moved along the rotational direction of the screw shaft 7 8).

Here, a NSL (Non-Self Locking) screw type, which is combined with the screw shaft 7 and the screw nut 8 by using a ball or roller type screw and minimizes frictional force during rotation and axial movement, is applied do.

In addition, the EMB is provided with a parking braking assy (not shown) engaged with the reducer 3 so as to restrain the jumping of the NSL (Non-Self Locking) screw type spindle 6 by using the solenoid 11 turned off after the parking brake, (10).

The parking brake assist 10 includes a solenoid 11, a switch gear 12 coupled to a rod shaft 11a of the solenoid 11, and a load shaft 12 extending from the solenoid 11 in an off- And a spring 13 which is compressed by a switchgear 12 which is moved toward the speed reducer 3 through an opening 11a.

Here, the switchgear 12 forms a chamfer 12a that slants the side surface of the gear, and the chamfer 12a is formed by a gear of the first and second gears 4 and 5 constituting the speed reducer 3 So that the switchgear 12 can smoothly be pushed in.

In addition, as the solenoid 11 is rotatable on the rod axis, the switch gear 12 rotates slightly while the switch gear 12 is not in the correct position between the first and second gears 4 and 5 So that it is not possible to have a conventional resolution so that wear correction can be implemented regardless of the degree of wear of the pad.

The rotation of the switch gear 12 with respect to the solenoid 11 is realized by the principle that the switch gear 12 and the first and second gears 4,5 restrain rotation by mutual rotation directions .

In addition, the electric brake apparatus is provided with a parking brake button for generating a separate electric signal to the ECU 1 side in the driver's seat area, for example, when the parking brake apparatus is operated so that the ECU 1 receives a signal for recognizing the parking brake switching state .

The caliper to which the EMB of the present invention is mounted is provided with inner and outer pads 9a and 9b disposed on both sides of the wheel disk D to press the wheel disk D, (Which is a function of a conventional caliper-type brake) that implements an interlocking action so that the outer pads 9b positioned opposite to the wheel disc D are also moved toward the wheel disc D And a pad wear detection sensor is usually provided in order to detect an increase in the interval between the wheel disks D in accordance with the setting interval of the pad and to keep the set interval at all times.

When the EMB (Electro Mechanical Brake) of the present invention is braked using the rotation of the speed reducer 3 through the actuator 2 that generates power under the control of the ECU 1, The first and second gears 4 and 5 constituting the speed reducer 3 are provided in the axial direction of the screw type spindle 6 to move the pads 9a and 9b toward the wheel disk D, Since the solenoid 11 is provided with the switchgear 12 interrupting the retreating movement of the spindle 6 in the state where the solenoid 11 is switched off after the parking brake, The solenoid 11 can restrain the speed reducer 3 to maintain the parking brake state so as not to be pushed back.

1, the EMB includes a pair of first and second gears 4 and 5 rotated together with an actuator 2 driven through an ECU 1 for determining whether to brak or park, The spindle 6 is axially moved through the first and second gears 4 and 5 so as to move the inner pad 9a toward the wheel disc D, .

In addition, a decelerator 3 for operating the spindle 6 is connected to the solenoid 11 (not shown) so as to prevent the braking force from being released due to the reaction force of the non-self locking (NSL) screw type spindle 6 after the parking brake, And a parking brake assist 10 that restrains the parking brake pedal 10 in an off state of the parking brake assist 10.

When the engine is turned on, the solenoid 11 is switched to the On state and the rod shaft 11a of the solenoid 11 is retracted to be fixed to the rod shaft 11a The switch gear 12 is shifted away from the first and second gears 4 and 5 and the spring 13 fixed to the switch gear 12 is in a tensioned state.

The braking operation implemented in the EMB having such a configuration is performed in such a manner that the ECU 1 drives the actuator 2 to rotate the speed reducer 3 to rotate the second gear 4 engaged with the first gear 4 constituting the speed reducer 3, The spindle 6 is operated while the gear 5 is rotated.

Thus, the spindle 6 to which the second gear 5 is coupled rotates the screw shaft 7 together with the second gear 5, and the rotation of the screw shaft 7 is transmitted through the NSL So that the screw nut 8, which is a screw type, is pulled out from the screw shaft 7.

The inner pad 9a is moved toward the wheel disk D by the axial movement of the screw nut 8 and the outer pad 9b located on the opposite side is also moved by the torque member action of the caliper to the wheel disk D ), The braking action is performed.

2, when the ECU 1 receives the parking signal and drives the actuator 2 to move the spindle 6 in the axial direction by the rotation of the speed reducer 3, The inner pad 9a and the outer pad 9b press the wheel disk D to form the parking brake force.

When the key braking force is generated by the action of the spindle 6, the solenoid 11 whose power is turned off is switched off and the rod shaft 11a is released, The switch gear 12 fixed to the rod shaft 11a is moved toward the first and second gears 4,5.

At this time, the spring 13 fixed to the switch gear 12 is returned to the initial state, and the switch gear 12 is pulled out.

The switch gear 12, which is pushed toward the first and second gears 4 and 5 and meshed with the gear, forms a chamfer 12a, which slopes the side surface of the gear, so that the first and second gears 4 , 5) into which the gears of the switch gears (12) are inserted smoothly.

When the inner and outer pads 9a and 9b press the wheel disc D and the parking brake is applied, the switch gear 12 is engaged with the gears of the first and second gears 4 and 5 The solenoid 11 to which the switch gear 12 is fixed strongly restricts the first and second gears 4 and 5.

The restraint of the first and second gears 4 and 5 through the solenoid 11 prevents the spindle 6 to which the second gear 5 is fixed from being pushed back by the reaction force received from the wheel disk D .

The ECU 1 further advances the spindle 6 in the axial direction when the gap between the inner and outer pads 9a and 9b is corrected by the gap between the inner and outer pads 9a and 9b and the wheel disk D, , The interval between the inner pad 9a and the outer pad 9b with respect to the wheel disk D is adjusted to maintain the set value.

After the pad wear correction is completed, when the solenoid 11 is turned off according to the key off, the switch gear 12, together with the rod shaft 11a of the solenoid 11, · Moved to the gears (4,5) and engaged.

As described above, the engagement between the switch gear 12 and the first and second gears 4 and 5 causes the reaction force of the spindle 6, which has been moved forward due to pad wear, Locking Screw type The spindle 6 restrains the movement to be pushed by the reaction force applied to the screw type spindle 6 and the pad setting interval corrected by the restraint of the spindle 6 using the solenoid 11 can be maintained.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a block diagram of an electric braking device having a parking braking function using a gear according to the present invention;

Fig. 2 is a diagram showing a parking braking operation of the electric braking device during parking braking according to the present invention. Fig.

    Description of the Related Art

1: ECU 2: Actuator

3: Reduction gears 4,5: 1st and 2nd gears

6: Spindle 7: Screw shaft

8: Screw nut 10: Parking brake assy

11: Solenoid 11a: Rod axis

12: Switchgear 12a: Chamfer

13: spring

Claims (5)

An ECU (1) for generating a control signal for braking together with measurement information on a vehicle running state when detecting a signal of an electronic pedal; An actuator (2) controlled through the ECU (1) to generate power; A speed reducer 3 composed of a second gear 5 which rotates together with a first gear 4 rotated together with the actuator 2; A spindle 6 rotated by the second gear 5 to generate an axial force to push the inner pad 9a toward the wheel disc D; The non-self locking (NSL) screw type spindle 6 receiving the reaction force from the wheel disk D is blocked by using the solenoid 11 switched off after the parking brake, A parking brake assy 10 and; And a caliper (20) provided inside the caliper body and having inner and outer pads (9a, 9b) for pressurizing and braking the wheel disc (D) The parking brake assistant 10 includes a solenoid 11, a switch gear 12 coupled to a rod shaft 11a of the solenoid 11, and a rod shaft 11a And a spring (13) that is compressed by a switchgear (12) that is moved toward the speed reducer (3) through the spring (13). The spindle according to claim 1, wherein the spindle (6) comprises a screw shaft (7) to which a second gear (5) constituting a speed reducer (3) And a screw nut (8). The electric braking device has a parking brake function using a gear. delete 2. The electric braking device according to claim 1, wherein the switchgear (12) has a chamfer (12a, Chamfer) formed by slanting a side surface of the gear. The electric braking device according to claim 1, wherein the switchgear (12) is allowed to rotate with respect to the solenoid (11).

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