KR101555377B1 - Regenerative brake system - Google Patents

Abstract

The present invention relates to a regenerative braking device in which front and rear wheel braking applied to all electric vehicles including a hybrid vehicle are independently implemented to eliminate a phenomenon in which a pedal feel of a driver is lowered, (ABS), which is designed to prevent excessive power generation on the front wheel, which is considered to be the design of the anti-brake system, Hydraulic Unit).

Regeneration, motor, cable

Description

[0001] Regenerative brake system [0002]

The present invention relates to a protecting function of a master cylinder which forms a braking hydraulic pressure through an actuator, in connection with the patent application 10-2009-0012388 (2009.2.16) filed by the present applicant.

Application No. 10-2009-0012388 (2009.2.16) filed by the present applicant in the present application is directed to an electro-hydraulic brake (EHB) or an electronic stability control (ESC) premium which requires a separate device for cost increase and prevention of pedal depression The present invention provides a regenerative braking device that does not apply the same device, is low in manufacturing cost, and does not lower the pedal feel of a driver without using a separate separating device.

Such a regenerative braking system is a system in which when the driver depresses the pedal, the front wheel is operated by the electric actuator and the rear wheel is operated by the driver's pedaling force.

For this purpose, an electric booster is used for the actuator that generates the braking hydraulic pressure on the front wheel side.

However, the front wheel side, which uses the power of the actuator, has a difficulty in requiring careful control for protecting the master cylinder.

For example, in the case where an excessive operation of the actuator occurs in the braking process or a flow rate of the wheel cylinder is introduced into the master cylinder, such as a reduction in pressure of the ABS (Anti Brake System), the pressure in the master cylinder may be excessively increased This should be taken into consideration when designing.

If the pressure rise in the master cylinder excessively occurs due to the above-mentioned reason, the master cylinder may cause damage to the hydraulic cylinder as well as the master cylinder. Therefore, There is a difficulty.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a braking system for braking a braking system which, unlike a rear wheel braking system using pedal operation force, basically blocks the risk that excessive braking force is generated in front braking using the braking force, There is an object to provide a regenerative braking device that does not require a design to prevent excessive increase of the speed of the regenerative braking device.

In addition, the present invention can prevent the pressure in the master cylinder from rising above a certain level in the front wheel braking using the electric power, and even when the depressurization of the ABS (Anti Brake System) And it is an object of the present invention to provide a regenerative braking device that does not cause damage to a hydraulic system (hydraulic unit) as well as a master cylinder.

According to an aspect of the present invention, there is provided a vehicular brake system including a rear wheel braking unit for performing a braking action by depression of a pedal, an actuator for detecting an operation of the pedal, And a front wheel braking section (10) installed to be driven independently of the rear wheel braking section (5) by the driving of the rear wheel braking section (11) to perform a braking action,

The front wheel brake 10 is a braking system that generates braking hydraulic pressure of the front wheel master cylinder 12 in an indirect manner in which the power of the actuator 11 is received and the piston 33 of the front wheel master cylinder 12 is moved. And a pressure controller (30).

The braking pressure controller 30 pulls the piston 33 built in the front wheel master cylinder 12 by using the power of the actuator 11 and pulls the piston 33 pulled out of the front wheel master cylinder 12 And the braking hydraulic pressure is formed by reducing the hydraulic pressure actual volume.

The braking pressure controller 30 includes a power medium 31 driven through an actuator 11 and a piston 33 built in the front wheel master cylinder 12 through the power medium 31 to generate 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, respectively.

The power medium 31 is rotated by 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, (32) is constituted by a cable whose one end is fixed to the piston (33) and the other end is connected 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 the front master cylinder 12 is excessively pressurized.

The relief valve 35 is installed in the 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 operation force, the electric power for generating the braking hydraulic pressure on the front wheel is not excessively generated, and there is a convenient effect of not considering the design for avoiding the overrun of the braking hydraulic pressure. The damper of the hydraulic cylinder (hydraulic unit) as well as the master cylinder is prevented from occurring even when the depressurization of the ABS (Anti Brake System), in which the flow rate of the wheel cylinder flows into the master cylinder and raises the pressure, is realized.

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.

FIG. 1 is a diagram showing an installation configuration in which a regenerative braking device according to the present invention is applied to an electric vehicle. The pedal 1 applied to the regenerative braking device of the present invention is a so- And a pair of pedals interlocked with each other.

For example, the pedal 1 applied to the present embodiment may include a driver's primary pedal and a primary pedal, such as the application number 10-2009-0012388 (2009.2.16) filed by the present applicant, A pair of secondary pedals interlocked with each other, and designed to have a high pedal ratio in a state where the primary pedal and the secondary pedal are combined.

In addition, the regenerative braking device of the present embodiment includes a rear wheel braking section 5 for directly receiving a stroke of the pedal 1 to form a braking hydraulic pressure supplied to the rear wheel brake B, (10) which forms the braking hydraulic pressure required in the front wheel brake (A) according to the front wheel braking force (A).

The front and rear wheel braking units 5 and 10 as described above can be independently implemented by separating the front wheel braking and the rear wheel braking as in the patent application 10-2009-0012388 (2009.2.16) filed by the present applicant, And one oil reservoir 13 provided on the side of the front wheel braking portion 10 in common is commonly used.

Further, the rear wheel brake unit 5 performs rear wheel braking by frictionless braking using only the driver force between the pedal and the master cylinder, while the front wheel brake unit 10 uses the actuator, so that the front- The pedal feeling of the driver is not lowered without affecting the rear wheel side.

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

The front wheel braking section 10 includes an actuator 11 for generating a power in accordance with a stroke of the pedal 1 and a braking hydraulic pressure generating section for generating braking hydraulic pressure of the front wheel brake A by the transmission power of the actuator 11 And an oil reservoir 13 for storing the oil supplied to the front master cylinder 12 and a braking hydraulic pressure generated by the front wheel master cylinder 12 to the front wheel brake A And the front wheel hydraulic line 14 is formed.

The actuator 11 applies a motor.

The front wheel hydraulic line 14 is composed of left and right hydraulic lines 14a and 14b respectively connected to 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), which is the front wheel brake (A).

The braking pressure controller 30 controls the braking pressure controller 30 such that the electric power of the actuator 11 constitutes the front wheel braking section 10 To prevent excessive action on the front wheel master cylinder (12) and to prevent excessive pressure rise in the front wheel master cylinder (12).

That is, the braking pressure controller 30 prevents an excessive power generation of the actuator 11 that generates the braking hydraulic pressure, and an ABS (Anti Brake System) that increases the pressure by flowing the flow rate toward the wheel cylinder into the front wheel master cylinder 12 ), A safety function that does not cause damages of the hydraulic system (Hydraulic Unit) as well as the front wheel master cylinder 12 is realized.

The braking pressure controller 30 includes a power medium 31 driven through the actuator 11 and a piston 33 built in the front wheel master cylinder 12 through the power medium 31 to generate 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, respectively.

Although the power medium 31 is variously implemented, in the present embodiment, a gear unit is applied, and the gear unit may be constituted by one member which is rotated through the actuator 11 and pulls the connecting member 32, A gear that is rotated through the gear 11 and a gear that rotates while the coupling member 32 is pulled.

For example, when the gear unit is composed of two or more gear units, the gear unit includes a first gear rotated through the actuator 11 and a second gear coupled to the first gear, So that the piston 33 is pulled out.

At this time, the second gear rotates in the reverse direction of the first gear to release the connecting member 32, and the piston 33 is pushed back by the action of the return spring 34.

Alternatively, the power medium 31 may be a screw shaft type that converts the rotational force into an axial movement force. The method includes a first screw shaft rotated through the actuator 11, And the second screw shaft pulls the piston 33 forward through the connecting member 32 by the rotation of the first screw shaft.

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

In this embodiment, a cable is used. The cable is fixed at one end to the piston 33 and the other end is coupled to the power medium 31, The piston 32 is pulled or pushed in accordance with the direction of motion of the piston 31.

In addition, the braking pressure controller 30 is further provided with a relief valve 35 to prevent an excessive pressure rise of the front wheel master cylinder 12. The relief valve 35 is connected to the front master cylinder 12, (13).

The relief valve 35 functions to maintain a constant internal pressure rise even when the flow rate of the wheel cylinder is introduced into the front wheel master cylinder 12 in the depressurization of the ABS (Anti Brake System).

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

The opening pressure of the relief valve 35 is determined according to the operating condition, but is normally operated when the pressure in the front wheel master cylinder 12 is about 160 bar to 200 bar.

The regenerative braking device according to the present embodiment is controlled by the ECU 20 as shown in Fig. 1. The ECU 20 is an ECU which is a kind of a vehicle that controls a vehicle under running. However, if necessary, The control unit also applies.

The ECU 20 receives the signal of the pedal sensor 4 that senses the stroke of the pedal 1 and controls the power of the actuator 11 of the front wheel brake 10, In addition to the pedal sensor 4, the ECU 20 forms a circuit with a plurality of pressure sensors provided in the rear wheel braking section 5 and the front wheel braking section 10.

The circuit configuration formed by the ECU 20 includes one rear wheel pressure sensor 9 on the rear wheel braking section 5, as described in Application No. 10-2009-0012388 (2009.16) filed by the present applicant And a pair of left and right front wheel pressure sensors 15 and 16 are provided in the front wheel brake 10.

The rear wheel pressure sensor 9 contributes to increase the stroke sensing accuracy of the pedal 1 by the ECU 20 and is a concept of implementing fail-safe for the pedal sensor 4 So that it is not necessary to actually install it.

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

The regenerative braking device according to the present embodiment includes a rear wheel brake (not shown) for implementing friction braking when the driver depresses the pedal 1, as described in Application No. 10-2009-0012388 (Feb. 16, 2009) At the same time, front wheel braking that implements regenerative braking occurs at the same time.

That is, when the driver depresses the pedal 1 to change the stroke, the rear wheel braking through the input of the pedal 1 is performed, and the front wheel braking through the power of the actuator 11 by the stroke change amount of the pedal 1 Lt; / RTI >

When the braking hydraulic pressure is generated in the rear wheel master cylinder 6 operated through the pedal 1 whose answer input is greatly enhanced by the high pedal ratio according to the present embodiment, the rear wheel brake B mounted on the left and right rear wheels, Implements braking with the hydraulic pressure supplied through the pair of left and right hydraulic lines 8a, 8b.

Since the rear wheel braking implemented through the pedal 1 always supplies the braking hydraulic pressure to the rear wheel side, even if the actuator 11 for the front wheel brakes fails, a separate fail-safe device And fail-safe can be realized to a certain extent without any problem.

During the rear wheel braking, the ECU 20 calculates the stroke of the pedal 1 via the pedal sensor 4 and calculates the braking hydraulic pressure supplied to the rear wheel brake B through the rear wheel pressure sensor 9 , And drives the actuator 11 using the calculated value to brake the front wheels.

The front wheel master cylinder 12 generates the 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 can preferentially block the power surge of the actuator 11, Internal pressure and elevation can be prevented.

That is, when the actuator 11 is driven through the ECU 20, the power medium 31 is actuated via the actuator 11, and the power medium 31 pulls the piston 33 to drive the front master cylinder 12 are operated.

2, when the power medium 31 pulls the piston 33 toward the actuator 11, the piston 33 pulls the return spring 34 and pulls the return spring 34 to the hydraulic pressure chamber 32 of the front wheel master cylinder 12, .

The reduction of the hydraulic pressure in the front wheel master cylinder 12 as described above forms the braking hydraulic pressure by raising the internal pressure, and the braking hydraulic pressure is transmitted to the left and right front wheels through the pair of left and right hydraulic lines 14a and 14b Is supplied to the mounted front wheel brake A, and acts as a braking force for braking the front wheels.

The ECU 20 controls the power of the actuator 11 to perform the target control on the front wheel master cylinder 12 in order to vary the braking force of the front left wheel and the right front wheel due to the characteristics of regenerative braking.

To this end, the ECU 20 calculates the stroke detection value of the pedal 1 using the pedal sensor 4 and the rear wheel pressure sensor 9, and calculates the stroke detection value of the pedal 1 using the front left and right front wheel pressure sensors 15, Use the braking oil pressure detection value on the brake (A) side as a control factor.

That is, the ECU 20 calculates the braking oil pressure magnitude at the time of measurement through the pair of left and right front wheel pressure sensors 15 and 16, and calculates the braking oil pressure magnitude at the time of measurement by using the pedal sensor 4 and the pedal pressure sensor 9 Calculates the required braking force magnitude in consideration of the stroke change value of the actuator (1), and changes the power of the actuator (11) accordingly.

For example, when the ECU 20 increases the current supply of the actuator 11, the braking oil pressure of the front master cylinder 12 also increases. Conversely, when the ECU 20 reduces the current supply of the actuator 11, The braking hydraulic pressure of the master cylinder 12 is reduced.

However, even when the front wheel braking force change occurs in front wheel braking, there is no mechanical connection structure with the pedal 1 side, so that the pedal deterioration of the pedal 1 does not occur due to the braking force change.

When the ECU 20 releases the power of the actuator 11, the piston 33 does not act on the power medium 31. Therefore, the tension spring 34 that has been pulled back is compressed again to move the piston 33 And pulls it back to its initial state.

In this front wheel master cylinder 12, stability is ensured in which the internal pressure is not excessively elevated during the front wheel braking because the operation of the relief valve 35 provided between the front wheel master cylinder 12 and the oil pressure line of the oil reservoir 13 .

That is, when depressurization of the ABS (Anti Brake System) is implemented, reverse flow of the flow rate toward the wheel cylinder toward the front wheel master cylinder 12 occurs. Such increase of the reverse flow rate raises the internal pressure of the front wheel master cylinder 12, The rise will not exceed about 160 bar to 200 bar.

This is because when the internal pressure of the front wheel master cylinder 12 rises to the range of about 160 bar to 200 bar, the relief valve 35 is opened with the rising pressure, and the internal flow rate of the front wheel master cylinder 12 is discharged toward the oil reservoir 13 , And when the internal pressure of the front wheel master cylinder (12) falls below about 160 bar to 200 bar, the relief valve (35) is closed again.

The operation 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, even when implementing the depressurization of the ABS (Anti Brake System), the hydraulic cylinder Unit) can be imparted with stability that does not cause damage.

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

2 is a block diagram of an actuator and a master cylinder constituting a front wheel braking portion according to the present invention

    Description of the Related Art

1: Pedal 4: Pedal sensor

5: rear wheel braking unit 6,12: rear / front wheel master cylinder

7: reservoir line 8,14: rear / front hydraulic line

8a, 8b: left and right hydraulic line 9: rear wheel pressure sensor

10: front wheel brake 11: actuator

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

15,16: Left and right front wheel pressure sensor

20: ECU 30: braking pressure controller

31: power medium 32: connecting member

33: piston 34: return spring

35: relief valve

A, B: front and rear brake

Claims (7)

A rear wheel braking unit that performs a braking action by depression of a pedal and a front wheel braking unit that is installed to be driven independently of the rear wheel braking unit by driving an actuator through an ECU that senses the operation of the pedal, In the regenerative braking device, Wherein the front wheel brake unit includes a braking pressure controller that generates braking hydraulic pressure of the front wheel master cylinder in an indirect manner in which the piston of the front wheel master cylinder is transferred by receiving the power of the actuator, Wherein the braking pressure controller draws a piston built in the front wheel master cylinder using the power of an actuator and the piston pulled to reduce the hydraulic pressure actual volume of the front wheel master cylinder to form a braking hydraulic pressure. delete The hydraulic control apparatus according to claim 1, wherein the braking pressure controller comprises: a power medium driven through an actuator; a connecting member for pulling a piston built in a front wheel master cylinder through the power medium to generate an oil pressure; And a return spring having both ends fixed to the piston. 4. 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 the connecting member is a cable having one end fixed to the piston and the other end coupled to the power medium. 4. The regenerative braking device according to claim 3, wherein the braking pressure controller further includes a relief valve that opens the hydraulic passage toward the oil reservoir when the pressure of the front master cylinder rises excessively. 7. The regenerative braking device according to claim 6, wherein the relief valve is provided in an oil line connected between the front master cylinder and the oil reservoir.

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