KR20100103986A - Regenerative brake system - Google Patents

Abstract

PURPOSE: A regenerative brake device is intended to provide the convenience of the design through the blocking of the excessive generation of the front wheel power and to prevent the damage of a master cylinder and a hydraulic system through the fundamental blocking of the pressure raise when realizing the decreased pressure for ABS. CONSTITUTION: A regenerative brake device comprises a rear wheel brake part(5), and a front wheel brake part(10). The rear wheel brake part performs a brake operation by the stepping of a pedal(1). The front wheel brake part drives by the drive of an actuator(11) through an ECU(20) sensing the operation of the pedal. The front wheel brake part drives independently of the rear wheel brake part and performs the brake operation. The front wheel brake part uses an indirect manner of receiving the power of the actuator and moving the piston of a front wheel master cylinder(12). The front wheel brake part comprises a brake pressure controller. The brake pressure controller generates the brake fluid pressure of the front wheel master cylinder.

Description

Regenerative brake system

The present invention is related to the present applicant filed in the domestic application No. 10-2009-0012388 (2009.2.16), to enhance the protection function of the master cylinder for forming the braking hydraulic pressure through the actuator.

Application No. 10-2009-0012388 (2009.2.16) filed by the applicant in Korea is an EHB (Electro-Hydraulic Brake) or ESC (Electronic Stability Control) premium, which requires a separate device for increasing costs and preventing pedal deterioration. Since the same device is not applied, it is possible to provide a regenerative braking device which is low in manufacturing cost and does not lower the pedal feel of the driver without using a separate separation device.

In the regenerative braking device as described above, when the driver presses the pedal, the front wheel is operated by the electric actuator, and the rear wheel is an independent and cooperative control which is operated by the pedal force of the driver.

For this purpose, the actuator that generates the braking hydraulic pressure on the front wheel applies an electric booster.

However, the front wheel side using the power of the actuator has a difficulty that requires careful control for protecting the master cylinder.

For example, if the actuator is excessively operated during braking or if the flow rate of the wheel cylinder flows into the master cylinder such as the decompression implementation of the ABS (Anti Brake System), the pressure in the master cylinder may be excessively increased. There is room for this, so design should take this into account.

If excessive pressure rise in the master cylinder occurs due to the above reasons, serious damage may occur not only to the master cylinder but also to the hydraulic system. Therefore, when designing, sufficient measures must be taken to prevent damage to the hydraulic system. There is a difficulty.

Accordingly, the present invention has been invented in view of the above. Unlike the rear wheel braking using the pedal operating force, it essentially blocks the risk of excessive electric power being formed in the front wheel braking using the electric power, and the electric power prevents the braking hydraulic pressure. It is an object of the present invention to provide a regenerative braking device that does not require a design that does not excessively rise.

In addition, the present invention prevents the pressure in the master cylinder from rising above a certain level in front wheel braking using electric power, so that the flow rate of the wheel cylinder flows into the master cylinder to reduce the pressure of the ABS (Anti Brake System). It is an object of the present invention to provide a regenerative braking device that does not cause damage to a hydraulic cylinder, as well as a master cylinder.

The present invention for achieving the above object, the actuator through the rear wheel braking unit (5) for performing a braking action by the depression of the pedal (1), and the ECU 20 that detects the operation of the pedal (1) In the regenerative braking device comprising a front wheel braking unit (10) which is installed to drive independently of the rear wheel braking unit (5) by the driving of (11) and performs a braking action,

The front wheel brake part 10 is a brake that generates braking hydraulic pressure of the front wheel master cylinder 12 in an indirect manner in which the piston 33 of the front wheel master cylinder 12 is moved by receiving the power of the actuator 11. It characterized in that it comprises a pressure controller (30).

The braking pressure controller 30 uses the power of the actuator 11 to pull the piston 33 embedded in the front wheel master cylinder 12, and the pulled piston 33 of the front wheel master cylinder 12 It is characterized by reducing the hydraulic chamber volume to form a braking hydraulic pressure.

The braking pressure controller 30 generates a hydraulic pressure by pulling the power medium 31 driven through the actuator 11 and the piston 33 embedded in the front wheel master cylinder 12 through the power medium 31. And a return spring 34 fixed at both ends to the inner wall of the front wheel master cylinder 12 and the piston 33.

The power medium 31 is rotated through the actuator 11 to pull the connecting member 32, or to convert the rotational force into an axial moving force to pull the connecting member 32, the connecting member The end 32 is fixed to the piston 33 and the other end is composed of a cable coupled to the power medium 31.

The braking pressure controller 30 is further provided with a relief valve 35 for opening the hydraulic passage toward the oil reservoir 13 when excessive pressure rise of the front wheel master cylinder 12.

The relief valve 35 is installed in an oil line connected between the front wheel master cylinder 12 and the oil reservoir 13.

According to the present invention, unlike the rear wheel braking using the pedal operating force, the electric power generating the front wheel braking hydraulic pressure is not excessively generated, and there is a convenient effect of not considering the design for avoiding the excessive rise of the braking hydraulic pressure. When the wheel cylinder flow rate flows into the master cylinder and the pressure is reduced in the ABS (Anti Brake System) to increase the pressure, the master cylinder and the hydraulic system have the effect of not causing damage.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the exemplary embodiments of the present invention may be embodied in various different forms, one of ordinary skill in the art to which the present invention pertains may be described herein. It is not limited to the Example to make.

1 is a diagram illustrating an installation configuration in which a regenerative braking apparatus according to the present invention is applied to an electric vehicle, wherein the pedal 1 applied to the regenerative braking apparatus of the present invention has an increased pedal ratio compared to a driver's direct manipulation. It consists of a pair of pedals that interlock with each other.

For example, the pedal 1 applied to the present embodiment is a primary pedal for driver operation, and the primary pedal, as in the applicant's domestic application No. 10-2009-0012388 (2009.2.16) It is designed to have a pair of secondary pedals that interlock, and to have a high pedal ratio in a state in which the primary pedal and the secondary pedal are combined.

In addition, the regenerative braking device of the present embodiment receives a stroke of the pedal 1 directly to form a braking hydraulic pressure supplied to the rear wheel brake B, and a stroke of the pedal. The front wheel braking unit 10 for forming the braking hydraulic pressure required by the front wheel brake (A) is further provided.

The front and rear wheel brake units 5 and 10 as described above are independently implemented by separating the front wheel brake and the rear wheel brake, as in Korean Patent Application No. 10-2009-0012388 (2009.2.16) filed by the applicant. In consideration of this, one oil reservoir 13 installed toward the front wheel braking unit 10 is commonly used.

In addition, while the rear wheel braking unit 5 performs rear wheel braking by friction braking using only the driver's force without a booster between the pedal and the master cylinder, the front wheel braking unit 10 uses the actuator, so that the front wheel hydraulic braking force is variable. Even without affecting the rear wheel side, the pedal feel of the driver does not decrease.

The rear wheel braking unit 5 is connected to the oil reservoir 13 by the reservoir line 7 and has a rear wheel master cylinder 6 which forms braking hydraulic pressure when the pedal 1 is stepped on, and the left and right rear wheels And a rear wheel hydraulic line 8 composed of a pair of left and right hydraulic lines 8a and 8b respectively leading to the rear wheel brake B for braking the engine.

The front wheel brake 10 generates an actuator 11 generating power according to a stroke of the pedal 1 and a braking hydraulic pressure of the front wheel brake A by the transmission power of the actuator 11. The front wheel master cylinder 12, the oil reservoir 13 storing the oil supplied to the front wheel master cylinder 12, and the braking hydraulic pressure generated by the front wheel master cylinder 12 are supplied to the front wheel brake A. The front wheel hydraulic line 14 is comprised.

The actuator 11 applies a motor.

In addition, the front wheel hydraulic line 14 as described above is composed of left and right hydraulic lines 14a and 14b respectively leading to the left and right front wheels, and the left and right hydraulic lines 14a and 14b are mounted on a wheel disk. Connect to the caliper (or drum) that is the front wheel brake (A).

In addition, the present embodiment further includes a braking pressure controller 30 on the front wheel braking unit 10, wherein the braking pressure controller 30 is the electric power of the actuator 11 constitutes the front wheel braking unit 10. It prevents excessive action on the front wheel master cylinder 12 and prevents excessive pressure rise in the front wheel master cylinder 12.

That is, the braking pressure controller 30 prevents excessive power generation of the actuator 11 that generates the braking hydraulic pressure, and the wheel cylinder flow rate flows into the front wheel master cylinder 12 to increase the pressure. Even in the case of implementing a reduced pressure), the front wheel master cylinder 12, as well as implements a safety function that does not cause damage to the hydraulic system (Hydraulic Unit).

To this end, the braking pressure controller 30 pulls the power medium 31 driven through the actuator 11 and the piston 33 embedded in the front wheel master cylinder 12 through the power medium 31 to hydraulic pressure. And a return spring 34 having both ends fixed to the inner wall of the front wheel master cylinder 12 and the piston 33.

The power medium 31 is implemented in various ways, but in the present embodiment applies a gear unit, the gear unit is composed of one that is rotated through the actuator 11 and pulling the connecting member 32, or the actuator In addition to the gear rotated through (11), it is implemented in various ways, such as two or more gears that pull the connecting member 32 while rotating.

For example, when the gear unit is composed of two or more, the first gear rotated through the actuator 11 and the second gear coupled thereto, the connection member 32 through the rotation of the second gear ) Is configured to pull the piston 33 while being wound.

At this time, the second gear is released by the reverse rotation of the first gear to the connecting member 32, the piston 33 is pushed back by the action of the return spring (34).

Alternatively, the power medium 31 may be configured as a screw shaft type for converting the rotational force to the axial movement force, this method is the first screw shaft rotated through the actuator 11 and the outer peripheral surface of the first screw shaft The second screw shaft pulls the piston 33 forward through the connecting member 32 by the rotation of the first screw shaft is coupled to the screw formed in the.

At this time, the second screw shaft pushes the piston 33 back through the connecting member 32 by the reverse rotation of the first screw shaft.

In addition, although the connecting member 32 is also variously implemented, in the present embodiment, a cable is used, one end of which is fixed to the piston 33, and the other end of which is coupled to the power medium 31. The piston 32 is pulled or pushed according to the direction of movement of the 31.

In addition, the brake pressure controller 30 is further provided with a relief valve 35 to prevent excessive pressure rise of the front wheel master cylinder 12, the relief valve 35 is the front wheel master cylinder 12 and the oil reservoir (13) Install on the connected oil line.

In particular, the relief valve 35 serves to maintain a constant internal pressure increase even when the flow rate of the wheel cylinder side flows into the front wheel master cylinder 12 during the decompression implementation of the anti brake system (ABS).

That is, when the front wheel master cylinder 12 forms an internal pressure exceeding a predetermined value by the flow rate flowing from the wheel cylinder side, the relief valve 35 is opened by the pressure of the front wheel master cylinder 12 to open the oil reservoir 13. It discharges the flow toward the side to act to lower the pressure in the front wheel master cylinder (12).

The opening pressure of the relief valve 35 as described above is determined according to the operating conditions, but typically operates when the pressure in the front wheel master cylinder 12 is about 160 bar to 200 bar.

The regenerative braking apparatus according to the present embodiment is controlled using the ECU 20 as shown in FIG. 1, and the ECU 20 is an ECU that is a kind of controlling a running vehicle. The control unit also applies.

The ECU 20 controls the power of the actuator 11 of the front wheel brake unit 10 by receiving a signal from the pedal sensor 4 that detects the stroke of the pedal 1. The ECU 20, together with the pedal sensor 4, forms a circuit with a plurality of pressure sensors installed in the rear wheel brake 5 and the front wheel brake 10.

The circuit configuration formed by the ECU 20 is one rear wheel pressure sensor 9 on the rear wheel braking part 5 as described in the applicant's domestic application No. 10-2009-0012388 (2009.2.16). ) And a pair of left and right front wheel pressure sensors 15 and 16 are installed in the front wheel braking unit 10.

The rear wheel pressure sensor 9 contributes to improving the stroke detection accuracy of the pedal 1 in the ECU 20 and implements a fail-safe for the pedal sensor 4. Therefore, it is not necessary to actually install.

However, the pair of left and right front wheel pressure sensors 15 and 16 are installed at positions as close to the left and right front wheels as possible, which means that the ECU 20 controls the left and right front wheel pressure sensors 15 and 16. It is to monitor the braking hydraulic pressure by using, and to control the target while changing the power of the actuator 11 during the braking process.

Such a regenerative braking device according to the present embodiment has a rear wheel braking which realizes friction braking when the driver presses the pedal 1, as described in the applicant's domestic application No. 10-2009-0012388 (2009.2.16). At the same time, front wheel braking, which implements regenerative braking, takes place simultaneously.

That is, when the driver presses the pedal 1 and a stroke change occurs, the rear wheel braking through the pedal input of the pedal 1 and the front wheel braking through the power of the actuator 11 by the stroke change amount of the pedal 1 are performed. Implement

According to the present embodiment, when the braking hydraulic pressure is generated in the rear wheel master cylinder 6 operated through the pedal 1 with the driver's input power greatly increased at a high pedal ratio, the rear wheel brakes B mounted on the left and right rear wheels, respectively. The brake implements braking by hydraulic pressure supplied through the pair of left and right hydraulic lines 8a and 8b.

As such, the rear wheel braking implemented through the pedal 1 always supplies braking hydraulic pressure to the rear wheel, so that even if the actuator 11 for the front wheel braking fails, a separate fail-safe device is provided. It can be implemented to some degree fail-safe.

During such rear wheel braking, the ECU 20 calculates the stroke of the pedal 1 through the pedal sensor 4, and at the same time calculates the braking hydraulic pressure supplied to the rear wheel brake B through the rear wheel pressure sensor 9. , By using the calculated value to drive the actuator 11 to brake the front wheels.

The front wheel master cylinder 12 generates braking hydraulic pressure in an indirect manner using the braking pressure controller 30 operated through the actuator 11 without directly receiving the driving force of the actuator 11.

When the front wheel master cylinder 12 is operated through the braking pressure controller 30 as described above, the braking pressure controller 30 may preferentially block the excessive power of the actuator 11, thereby preventing the front wheel master cylinder 12. Internal pressure rise can be prevented.

That is, when the actuator 11 is driven through the ECU 20, the power medium 31 is operated through the actuator 11, and the power medium 31 pulls the piston 33 to form the front wheel master cylinder ( 12) is activated.

This process, as shown in Figure 2, when the power medium 31 pulls the piston 33 toward the actuator 11, the piston 33 is tensioning the return spring 34, the hydraulic chamber of the front wheel master cylinder 12 Will be narrowed down.

The reduction of the hydraulic chamber volume of the front wheel master cylinder 12 as described above raises the internal pressure to form braking hydraulic pressure, and the formed braking hydraulic pressure is respectively applied to the left and right front wheels through a pair of left and right hydraulic lines 14a and 14b. It is supplied to the mounted front wheel brake A and acts as a braking force for braking the front wheel.

Due to the characteristics of regenerative braking during front wheel braking, the ECU 20 controls the power of the actuator 11 to vary the braking force of the left and right front wheels to perform target control on the front wheel master cylinder 12.

To this end, the ECU 20 includes a front wheel using a pair of left and right front wheel pressure sensors 15 and 16 together with stroke detection values of the pedal 1 using the pedal sensor 4 and the rear wheel pressure sensor 9. The brake hydraulic pressure detection value on the brake A side is used as a control factor.

That is, the ECU 20 calculates the braking hydraulic pressure at the time of measurement through a pair of left and right front wheel pressure sensors 15 and 16 and calculates a pedal calculated through the pedal sensor 4 and the rear wheel pressure sensor 9. The braking force magnitude required is calculated in consideration of the stroke change value in (1), and then the power of the actuator 11 is changed accordingly.

For example, when the ECU 20 increases the current supply of the actuator 11, the braking hydraulic pressure of the front wheel master cylinder 12 also increases, and conversely, when the ECU 20 decreases the current supply of the actuator 11, the front wheels. The amount of braking hydraulic pressure of the master cylinder 12 is reduced.

However, even when the front wheel braking force change occurs during braking of the front wheel, there is no mechanical connection configuration with the pedal 1 side, and thus the pedal feeling of the pedal 1 is not lowered due to the change of the braking force.

When the ECU 20 releases the power of the actuator 11, the piston 33 has no force action through the power medium 31, and thus the tensioned return spring 34 is compressed again to lift the piston 33. Pull it back to the initial state.

The front wheel master cylinder 12 when the front wheel braking is implemented to ensure that the internal pressure is not excessively raised, which is the action of the relief valve 35 installed between the hydraulic line of the front wheel master cylinder 12 and the oil reservoir 13 Is implemented.

That is, in the case of the decompression implementation of the ABS (Anti Brake System), the reverse flow of the wheel cylinder side flow toward the front wheel master cylinder 12 occurs, and the increase in the reverse flow rate increases the internal pressure of the front wheel master cylinder 12, but the internal pressure is increased. The rise will not exceed about 160 bar to 200 bar.

This means that when the internal pressure of the front wheel master cylinder 12 is raised to a region of about 160 bar to 200 bar, the relief valve 35 is opened at the rising pressure, and the internal flow rate of the front wheel master cylinder 12 is discharged toward the oil reservoir 13. When the internal pressure of the front wheel master cylinder 12 falls below about 160 bar to 200 bar, the relief valve 35 is repeatedly closed.

The action of the relief valve 35 always maintains the internal pressure of the front wheel master cylinder 12 at about 160 bar to 200 bar or less. Therefore, the hydraulic system (Hydraulic) as well as the master cylinder is realized even when the ABS (Anti Brake System) is implemented at a reduced pressure. It can give stability without damage to the unit).

1 is a block diagram of a regenerative braking apparatus according to the present invention

Figure 2 is a block diagram of the actuator and the master cylinder forming the front wheel brake according to the invention

    <Description of the symbols for the main parts of the drawings>

1: Pedal 4: Pedal Sensor

5: Rear wheel brake 6,12 Rear and front wheel master cylinder

7: Reservoir line 8,14: Rear and front wheel hydraulic lines

8a, 8b: Left / Right Hydraulic Line 9: Rear Wheel Pressure Sensor

10: front wheel braking unit 11: the actuator

13: Oil reservoir 14a, 14b: Left and right hydraulic line

15,16: Left and right front wheel pressure sensor

20 ECU 30 Braking Pressure Controller

31 power medium 32 connection member

33: piston 34: return spring

35: relief valve

A, B: Front and rear brakes

Claims (7)

A rear wheel braking unit that performs a braking action by depressing a pedal and a front wheel braking unit that is installed to drive independently of the rear wheel braking unit by driving an actuator through an ECU that senses operation of the pedal. In the configured regenerative braking device, And the front wheel brake unit includes a brake pressure controller configured to generate braking hydraulic pressure of the front wheel master cylinder in an indirect manner in which the piston of the front wheel master cylinder is moved by receiving the power of the actuator. The braking pressure controller of claim 1, wherein the braking pressure controller pulls a piston embedded in the front wheel master cylinder by using the power of an actuator, and the pulled piston reduces the hydraulic chamber volume of the front wheel master cylinder to form a braking hydraulic pressure. Regenerative braking system. 3. The braking pressure controller according to claim 2, wherein the braking pressure controller comprises: a power medium driven through an actuator; a connecting member configured to pull a piston built into the front wheel master cylinder through the power medium to generate hydraulic pressure; and an inner wall of the front wheel master cylinder and the A regenerative braking device, characterized in that the return spring is fixed to both ends of the piston. The regenerative braking device according to claim 3, wherein the power medium is rotated through the actuator to pull the connecting member or to convert the rotational force into an axial moving force to pull the connecting member. The regenerative braking device according to claim 3, wherein one end of the connection member is fixed to the piston and the other end is a cable coupled to the power medium. The regenerative braking device according to claim 3, wherein the braking pressure controller is further provided with a relief valve that opens the hydraulic passage toward the oil reservoir when excessive pressure rise of the front wheel master cylinder occurs. The regenerative braking device according to claim 6, wherein the relief valve is installed in an oil line connected between the front wheel master cylinder and the oil reservoir.

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