KR20190035256A - Electric brake system - Google Patents

Abstract

Disclosed is an electronic brake system capable of quickly and effectively providing hydraulic pressure. According to one embodiment of the present invention, the electronic brake system comprises: a hydraulic pressure supply device; a first hydraulic flow path communicating with a first pressure chamber of the hydraulic pressure supply device; second and third hydraulic flow paths branched from the first hydraulic flow path; a fourth hydraulic flow path communicating with a second pressure chamber of the hydraulic pressure supply device; fifth and sixth hydraulic flow paths branched from the fourth hydraulic flow path; a seventh hydraulic flow path connecting the second and third hydraulic flow paths; an eighth hydraulic flow path connecting the second and seventh hydraulic flow paths; first to sixth control valves disposed in the second, third, fifth, sixth, seventh, and eighth hydraulic flow paths to control the flow of oil; a first hydraulic circuit disposed to be connected to two wheel cylinders from the second or fifth hydraulic flow path, respectively; and a second hydraulic circuit disposed to be connected to the two wheel cylinders from the third or sixth hydraulic flow path, respectively. The first to fifth control valves are a check valve, the third control valve is a check or solenoid valve, and the sixth control valve is a solenoid valve.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic brake system, and more particularly, to an electronic brake system that generates a braking force using an electrical signal corresponding to a displacement of a brake pedal.

In general, a vehicle is equipped with a brake system for braking, and in recent years, various types of systems have been proposed to obtain a more powerful and stable braking force.

For example, the brake system includes an anti-lock brake system (ABS) to prevent wheel slippage during braking, a brake traction control system (BTCS: Brake Traction (Electronic Stability Control System) that stably maintains the running condition of the vehicle by controlling the brake hydraulic pressure by combining anti-lock brake system and traction control.

In the conventional brake system, when the driver depresses the brake pedal, the hydraulic pressure required for braking is supplied to the wheel cylinder by using a mechanically connected vacuum booster. In recent years, however, a pedal displacement sensor, which detects the displacement of the brake pedal when the driver depresses the brake pedal There is widely used an electronic brake system having a hydraulic pressure supply device that receives a braking force of a driver as an electric signal and supplies a hydraulic pressure necessary for braking to the wheel cylinder.

EP 2 520 473 A1 (Honda Motor Co., Ltd.) According to this document, the hydraulic pressure supply device of the electronic brake system operates the motor in accordance with the spring force of the brake pedal, converts the rotational force of the motor into linear motion, and presses the piston of the cylinder, thereby generating a hydraulic pressure necessary for braking.

Embodiments of the present invention provide an electronic braking system including a hydraulic pressure supply device that operates in a double acting manner.

According to an aspect of the present invention, there is provided a hydraulic pressure generating apparatus that generates a hydraulic pressure using a hydraulic piston operated by an electrical signal outputted in response to displacement of a brake pedal, and is provided at one side of a hydraulic piston accommodated movably in a cylinder block, A hydraulic pressure supply device including a first pressure chamber connected to the wheel cylinder and a second pressure chamber provided on the other side of the hydraulic piston and connected to at least one wheel cylinder; A first hydraulic oil communicating with the first pressure chamber; A second hydraulic oil branching from the first hydraulic oil passage; A third hydraulic oil branching from the first hydraulic oil passage; A fourth hydraulic oil communicating with the second pressure chamber; A fifth hydraulic oil branched from the fourth hydraulic oil passage and joined to the second hydraulic oil passage; A sixth hydraulic oil branching from the fourth hydraulic oil passage and joining to the third hydraulic oil passage; A seventh hydraulic oil connecting the second hydraulic oil passage and the third hydraulic oil passage; An eighth hydraulic oil connecting the second hydraulic oil passage and the seventh hydraulic oil passage; A first control valve provided in the second hydraulic oil passage for controlling the flow of the oil; A second control valve provided in the third hydraulic oil passage for controlling the flow of the oil; A third control valve provided in the fifth hydraulic oil passage for controlling the flow of the oil; A fourth control valve provided in the sixth hydraulic oil passage for controlling the flow of the oil; A fifth control valve provided in the seventh hydraulic oil passage for controlling the flow of oil; A sixth control valve provided in the eighth hydraulic oil passage for controlling the flow of oil; A first hydraulic circuit that is connected to the two wheel cylinders in the second hydraulic oil passage or the fifth hydraulic oil passage, respectively; Wherein the first control valve and the second control valve are arranged in such a manner that the first control valve and the second control valve are connected to the wheel cylinders in the third hydraulic oil passage or the sixth hydraulic oil passage, The fourth control valve is provided with a check valve that allows the flow of oil in the direction from the hydraulic pressure supply device to the wheel cylinder but blocks the flow of oil in the opposite direction, The fifth control valve is provided as a fifth control valve provided between the second hydraulic oil passage and the eighth hydraulic oil passage and the 5-2 control valve provided between the third hydraulic oil passage and the eighth hydraulic oil passage, The 5-1 control valve is provided as a check valve that allows the flow of oil in the direction from the second hydraulic oil path to the eighth hydraulic oil path and blocks the flow of oil in the opposite direction, The valve The sixth control valve is provided as a solenoid valve capable of controlling the bidirectional flow, and the sixth control valve is provided as a check valve that allows the flow of oil in the direction from the pressure path to the eighth hydraulic oil path, A brake system may be provided.

In addition, the third control valve may be provided as a solenoid valve capable of controlling the bidirectional flow.

In addition, the third control valve may be provided in a normally closed type.

Also, the third control valve may be provided as a check valve that allows the flow of oil in the direction from the hydraulic pressure supply device to the wheel cylinder, but blocks the flow of oil in the opposite direction.

A reservoir in which oil is stored; A master cylinder connected to the reservoir; And a simulation device for providing a reaction force according to the power of the brake pedal using the oil flowing out from the master cylinder, wherein the simulation device is provided in a reservoir passage connecting the reservoir and the master cylinder to the simulation device, And a solenoid valve for controlling the flow of the bi-directional flow to the bypass flow passage. The flow control valve may include a check valve that allows fluid flow only in the direction of the check valve, a bypass flow path that connects the check valve and the check valve,

The solenoid valve may be a normally closed type.

A first dump passage communicating with the first pressure chamber and connected to the reservoir; a second dump passage communicating with the second pressure chamber and connected to the reservoir; The first dump passage being provided in the first dump passage to control the flow of the oil while allowing the flow of oil in the direction from the reservoir to the first pressure chamber while blocking the flow of oil in the opposite direction, And a check valve provided in the second dump passage for shutting off the flow of oil in the opposite direction while allowing the flow of oil in the direction from the reservoir to the second pressure chamber while controlling the flow of oil A second dump valve and a bypass passage connecting the upstream side and the downstream side of the second dump valve in the second dump passage to control the flow of the oil, Third dump valve provided in jeobeo and the second solenoid valve for controlling the flow in the positive direction between the second pressure chamber oil; a may further include.

And a reservoir in which oil is stored, the reservoir having a first reservoir chamber connected to recover oil dumped from the first hydraulic circuit, a second reservoir chamber connected to supply oil to the hydraulic pressure supply device, And a third reservoir chamber connected to recover oil dumped from the second hydraulic circuit, wherein the first reservoir chamber and the third reservoir chamber are separately provided.

The second reservoir chamber may be separate from the first reservoir chamber and the third reservoir chamber.

The electronic brake system according to the embodiment of the present invention can provide the hydraulic pressure more quickly and effectively by configuring the hydraulic piston of the hydraulic pressure supply device in a double-acting manner.

Further, in the electronic brake system according to the embodiment of the present invention, a plurality of control valves for controlling the flow of oil between the hydraulic pressure supply device and the wheel cylinder are constituted by a solenoid valve and a check valve so that hydraulic pressure necessary for braking It can provide quick or reduced pressure.

Further, the electronic brake system according to the embodiment of the present invention can reduce operating noise since the number of valves operated in operation is smaller than that in the conventional art.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a hydraulic circuit diagram showing an uninterrupted state of an electronic brake system according to an embodiment of the present invention; FIG.
2 is an enlarged view showing a master cylinder and a reservoir of an electronic brake system according to an embodiment of the present invention.
3 is an enlarged view showing a connection relationship between the reservoir and the hydraulic circuit according to the embodiment of the present invention.
4 is an enlarged view showing a hydraulic pressure providing unit provided in a hydraulic pressure supply device of an electronic brake system according to an embodiment of the present invention.
5 is a hydraulic circuit diagram showing a situation in which the hydraulic piston of the electronic brake system according to the embodiment of the present invention advances and provides the braking pressure in the low pressure mode.
6 is a hydraulic circuit diagram showing a situation in which the hydraulic piston of the electromagnetic brake system according to the embodiment of the present invention provides a braking pressure in the high pressure mode while advancing.
FIG. 7 is a hydraulic circuit diagram showing a situation in which the hydraulic piston of the electromagnetic brake system according to the embodiment of the present invention provides a braking pressure while reversing. FIG.
8 is a hydraulic circuit diagram showing a situation where the hydraulic pressure piston of the electromagnetic brake system according to the embodiment of the present invention is reversed and the braking pressure is released in the high pressure mode.
9 is a hydraulic circuit diagram showing a situation where the hydraulic pressure piston of the electromagnetic brake system according to the embodiment of the present invention is reversed and the braking pressure is released in the low pressure mode.
10 is a hydraulic circuit diagram showing a state in which the electronic brake system according to the embodiment of the present invention is operated in the inspection mode to check whether the simulator apparatus is leaking.
11 is a hydraulic circuit diagram showing a non-synchronized state of an electromagnetic brake system according to another 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 order to clearly explain the present invention, parts not related to the description are omitted from the drawings, and the width, length, thickness, etc. of the components may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a hydraulic circuit diagram showing an uninterrupted state of an electronic brake system according to an embodiment of the present invention; FIG.

Referring to the drawings, an electronic brake system 1 typically includes a master cylinder 20 for generating hydraulic pressure, a reservoir 30 coupled to an upper portion of the master cylinder 20 for storing oil, a brake pedal 10 An input rod 12 for pressurizing the master cylinder 20 in accordance with the pressing force of the brake pedal 20 and a wheel cylinder 40 for transmitting braking force to the wheels FL, RR, RL and FR, 10 for detecting the displacement of the brake pedal 10 and a simulation device 50 for providing a reaction force according to the leg-power of the brake pedal 10.

The master cylinder 20 may be configured to include at least one chamber to generate hydraulic pressure. For example, the master cylinder 20 according to the present embodiment may include a first master chamber 20a and a second master chamber 20b.

The first master chamber 20a is provided with a first piston 21a connected to the input rod 12 and the second master chamber 20b is provided with a second piston 22a. The first master chamber 20a communicates with the first hydraulic port 24a to allow the oil to flow in and out, and the second master chamber 20b communicates with the second hydraulic port 24b to receive the oil. For example, the first hydraulic port 24a may be connected to the first backup hydraulic channel 251, and the second hydraulic port 24b may be connected to the second backup hydraulic channel 252. [

The master cylinder 20 has two master chambers 20a and 20b to ensure safety in case of failure. The master chamber 20a of one of the two master chambers 20a and 20b is connected to the left rear wheel RL and the right front wheel FR of the vehicle through the first backup oil passage 251, The chamber 20b may be connected to the left front wheel FL and the right rear wheel RR through the second backup oil passage 252. [ By independently configuring the two master chambers 20a and 20b, it is possible to brake the vehicle even if one of the master chambers fails.

Alternatively, the master chamber of one of the two master chambers may be connected to the two front wheels FR and FL, and the other master chamber may be connected to the two rear wheels RR and RL, as shown in the figure. Or one of the two master chambers may be connected to the left front wheel FL and the left rear wheel RL and the other master chamber to the right rear wheel RR and the right front wheel FR. That is, the positions of the wheels connected to the master chambers of the master cylinder 20 can be variously configured.

A first spring 21b is provided between the first piston 21a and the second piston 22a of the master cylinder 20 and a second spring 21b is provided between the end of the master cylinder 20 and the second piston 22a. 2 spring 22b may be provided. That is, the first piston 21b is accommodated in the first master chamber 20a, and the second piston 22b is accommodated in the second master chamber 20b.

The first spring 21b and the second spring 22b are compressed by the first piston 21a and the second piston 22a which move as the displacement of the brake pedal 10 changes. When the pushing force of the first piston 21a becomes smaller than the elastic force, the first and second pistons 21a and 22a return to their original positions by using the restoring elastic force stored in the first spring 21b and the second spring 22b .

The input rod 12 for pressing the first piston 21a of the master cylinder 20 can be brought into close contact with the first piston 21a. That is, a gap may not exist between the master cylinder 20 and the input rod 12. [ Therefore, when the brake pedal 10 is depressed, the input rod 12 can press the master cylinder 20 directly without the pedal invalid stroke section.

2, the first master chamber 20a is connected to the reservoir 30 through the first reservoir passage 37 and the second master chamber 20b is connected to the second reservoir passage 38. [ The reservoir 30 may be connected to the reservoir 30. The first reservoir flow path 37 is connected to the lower side of the master cylinder 20 and the second reservoir flow path 38 is connected to the upper side of the master cylinder 20 The connecting position may be provided on the same side of the master cylinder 20. [ The first reservoir flow path 37 located below the master cylinder 20 is connected to a simulation device 50 to be described later.

The master cylinder 20 includes two sealing members 25a and 25b disposed on the front and rear of the first reservoir passage 37 and two sealing members 25c and 25d disposed on the front and rear sides of the second reservoir passage 38 . The sealing members 25a, 25b, 25c and 25d may be in the form of a ring protruding from the inner wall of the master cylinder 20 or the outer peripheral surface of the pistons 21a and 22a.

The flow of the oil flowing into the reservoir 30 from the first master chamber 20a is blocked while allowing the flow of the oil flowing into the first master chamber 20a from the reservoir 30 to the first reservoir passage 37 A check valve 55 may be provided. The front and rear of the check valve 55 may be connected by a bypass flow path 39 in which an electronic control valve for electrically controlling the bidirectional oil flow between the reservoir 30 and the master cylinder 20 An opening / closing valve 54 may be provided. The electromagnetic opening / closing valve 54 may be provided with a normally closed type solenoid valve that is normally closed and operates to open the valve when receiving an open signal from the electronic control unit. The electromagnetic opening / closing valve 54 may be used for operation of the simulator device 50 and leak detection. Details will be described later.

On the other hand, the reservoir 30 may include three reservoir chambers 31, 32, 33 as shown in FIGS. In one example, the three reservoir chambers 31, 32, 33 may be arranged side by side in a row.

Adjacent reservoir chambers 31, 32, 33 may be separated by partition walls 34, 35. For example, the first reservoir chamber 31 and the second reservoir chamber 32 are divided into first partition walls 34 and the second reservoir chamber 32 and the third reservoir chamber 33 are partitioned into the second partition wall 35).

The first and third partition walls 34 and 35 are partly opened to allow the first to third reservoir chambers 31, 32 and 33 to communicate with each other. Accordingly, the pressures of the first to third reservoir chambers 31, 32, and 33 may be equal to each other, and may be equally provided at, for example, atmospheric pressure.

The first reservoir chamber 31 can be connected to the first master chamber 20a of the master cylinder 20, the wheel cylinder 40 and the simulation apparatus 50 as shown in Fig. That is, the first reservoir chamber 31 can be connected to the first master chamber 20a and the simulation apparatus 50 through the first reservoir passage 37, and also to the two wheel cylinders 40 of the four wheel cylinders 40 Can be connected to the wheel cylinder 40 of the first hydraulic circuit 201 in which the first and second hydraulic circuits RL and FR are disposed.

The connection between the first reservoir chamber 31 and the first master chamber 20a and the simulation apparatus 50 can be controlled by the check valve 55 and the electromagnetic opening / closing valve 54, not shown in FIG. And the connection between the first reservoir chamber 31 and the wheel cylinder 40 can be controlled by the first and second outlet valves 222a and 222b (see FIG. 1).

The second reservoir chamber 32 may be connected to a hydraulic pressure supply device 100 to be described later. For example, referring to FIG. 1, the second reservoir chamber 32 may be connected to the first pressure chamber 112 and the second pressure chamber 113 of the hydraulic pressure providing unit 110. More specifically, the second reservoir chamber 32 is connected to the first pressure chamber 112 through the first dump passage 116 and to the second pressure chamber 113 through the second dump passage 117 .

The third reservoir chamber 33 can be connected to the second master chamber 20b of the master cylinder 20 and the wheel cylinder 40 as shown in Fig. That is, the third reservoir chamber 33 can be connected to the second master chamber 20b through the second reservoir passage 38, and the other two wheel cylinders FL and RR of the four wheel cylinders 40 And can be connected to the wheel cylinder 40 of the second hydraulic circuit 202 to be disposed (see Fig. 1). The connection of the third reservoir chamber 33 and the wheel cylinder 40 can be controlled by the third and fourth outlet valves 222c and 222d.

According to the present embodiment, the reservoir 30 includes a second reservoir chamber 32 connected to the hydraulic pressure supply device 100, first and third reservoir chambers 20a and 20b connected to the first and second master chambers 20a and 20b, (31, 33) can be separately provided. This is because if the reservoir chamber for supplying oil to the hydraulic pressure supply device 100 and the reservoir chamber for supplying oil to the master chambers 20a and 20b are provided in the same manner, If the oil can not be supplied, the master chambers 20a and 20b can not supply the oil properly.

Therefore, the reservoir 30 is provided separately from the second reservoir chamber 32 and the first and third reservoir chambers 31 and 33, so that even in an emergency in which oil can not be properly supplied to the hydraulic pressure supply device 100, The controller 30 can normally supply oil to the first and second master chambers 20a and 20b to perform emergency braking.

Similarly, the reservoir 30 may separately provide a first reservoir chamber 32 connected to the first master chamber 20a and a third reservoir chamber 33 connected to the second master chamber 20b. This is because if the reservoir chamber for supplying oil to the first master chamber 20a and the reservoir chamber for supplying oil to the second master chamber 20b are provided in the same manner, The oil can not be properly supplied to the second master chamber 20b.

Therefore, the reservoir 30 is provided separately from the first reservoir chamber 31 and the third reservoir chamber 33, so that even in an emergency in which oil can not be properly supplied to the first master chamber 20a, The normal braking pressure can be formed in at least two wheel cylinders 40 of the four wheel cylinders 40 by normally supplying the oil to the two master chambers 20b.

The reservoir 30 separates the dump lines connected to the oil lines 116 and 117 connected to the reservoir 32 from the hydraulic pressure supply device 100 and the reservoirs 31 and 33 from the wheel cylinder 40 . Therefore, it is possible to prevent the ABS performance from being lowered because bubbles that may occur in the dump line at the ABS braking are not introduced into the first and second pressure chambers 112, 113 of the hydraulic pressure supply device 100.

Hereinafter, the first to third reservoir chambers 31, 32, 33 are collectively referred to as a reservoir 30 for convenience of explanation.

Meanwhile, the simulation apparatus 50 may be connected to the first backup passage 251 to provide a reaction force according to the pressing force of the brake pedal 10. The reaction force is provided as much as the driver's compensation is compensated for, so that the driver can finely adjust the braking force as intended.

1, the simulation apparatus 50 includes a simulation chamber 51 configured to store oil flowing out from the first hydraulic port 24a of the master cylinder 20, A pedal simulator having a piston 52 and a reaction force spring 53 for resiliently supporting the reaction force piston 52 and a simulator valve 54 connected to the rear end of the simulation chamber 51.

The inside of the simulation chamber 51 is always filled with oil. Therefore, the friction of the reaction force piston 52 is minimized during the operation of the simulation apparatus 50, so that the durability of the simulation apparatus 50 is improved, and foreign matter from the outside can be intrinsically blocked. The front end of the simulation chamber 51 is connected to the master cylinder 20 and the rear end of the simulation chamber 51 is connected to the reservoir 30.

The reaction force piston 52 and the reaction force spring 53 are installed so as to have a certain range of displacement in the simulation chamber 51 by the oil introduced into the simulation chamber 51.

The simulator valve 54 may be provided in a flow path connecting the rear end of the simulation chamber 51 and the reservoir 30. The flow path may use the first reservoir flow path 37. [ That is, the rear end of the simulation chamber 51 can be connected to the reservoir 30 via the simulator valve 54 on the first reservoir flow path 37. The inside of the simulation chamber 51 can be always filled with oil by flowing oil from the reservoir 30 when the reaction force piston 52 returns.

Further, the simulator valve 54 may be constituted by a closed type solenoid valve that keeps the normally closed state. The simulator valve 54 can be opened when the driver applies pressure to the brake pedal 10 to deliver the oil in the simulation chamber 51 to the reservoir 30.

Further, a simulator check valve 55 may be installed in the simulator valve 54 in parallel. The simulator check valve 55 is provided to allow the flow of oil from the reservoir 30 to the simulator chamber 51 and to block the flow of oil in the opposite direction so that when the brake pedal 10 is de- Can be guaranteed.

The simulator valve 54 and the simulator check valve 55 are also usable for checking whether the simulator device 50 described above is leaking. Details will be described later.

The electronic brake system 1 according to the present embodiment includes a hydraulic pressure supply device 100 (hereinafter, referred to as " hydraulic pressure supply device 100 ") that receives mechanically the braking force of the driver from the pedal displacement sensor 11 for sensing the displacement of the brake pedal 10, And first and second hydraulic circuits 201 and 202 for controlling the flow of hydraulic pressure to the wheel cylinders 40 provided in the two wheels RL, FR, FL and RR, respectively, A first cut valve 261 provided in a first backup passage 251 for connecting the first hydraulic pressure port 24a of the master cylinder and the first hydraulic circuit 201 to control the flow of hydraulic pressure, A second cut valve 262 provided on a second backup passage 252 connecting the second hydraulic pressure port 24b of the master cylinder and the second hydraulic circuit 202 to control the flow of the hydraulic pressure, The hydraulic pressure supply device 100 and the valves 54, 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 233, 6, and 243, which are connected to each other.

The hydraulic pressure supply device 100 includes a hydraulic pressure supply unit 110 for supplying oil pressure to the wheel cylinder 40, a motor 120 for generating a rotational force by an electrical signal of the pedal displacement sensor 11, And a power conversion unit 130 that converts the rotational motion of the motor 120 into a linear motion and transfers the rotational motion to the hydraulic pressure providing unit 110. Here, the hydraulic pressure providing unit 110 may be operated not by the driving force supplied from the motor 120 but by the pressure provided by the high-pressure accumulator.

The hydraulic pressure providing unit 110 will be described in more detail below with reference to Fig.

The hydraulic pressure providing unit 110 includes a cylinder block 111 in which a pressure chamber to be stored with oil is formed, a hydraulic piston 114 housed in the cylinder block 111, a hydraulic piston 114 and a cylinder block 111 A driving shaft 115 connected to a rear end of the hydraulic piston 114 to transmit power output from the power converting unit 130 to the hydraulic piston 114; (133).

The pressure chamber includes a first pressure chamber 112 positioned forward (forward direction, leftward direction in the drawing) of the hydraulic piston 114 and a second pressure chamber 112 positioned rearward (backward direction, rightward in the drawing) of the hydraulic piston 114 And may include a second pressure chamber 113.

The first pressure chamber 112 is divided by the front end of the cylinder block 111 and the hydraulic piston 114 so that the volume of the second pressure chamber 112 is changed according to the movement of the hydraulic piston 114, Is divided by the cylinder block 111 and the rear end of the hydraulic piston 114 so as to be varied in volume as the hydraulic piston 114 moves.

The first pressure chamber 112 is connected to the first hydraulic fluid passage 211 through the first communication hole 111a formed on the rear side of the cylinder block 111 and the second pressure chamber 113 is connected to the cylinder block 111 111 via the second communication hole 111b formed on the front side of the fourth hydraulic oil passage 214. [

The first hydraulic oil path 211 connects the first pressure chamber 112 and the first and second hydraulic circuits 201, 202. The first hydraulic fluid path 211 is branched into a second hydraulic fluid path 212 communicating with the first hydraulic circuit 201 and a third hydraulic fluid path 213 communicating with the second hydraulic circuit 202. The fourth hydraulic fluid passage 214 connects the second pressure chamber 113 and the first and second hydraulic circuits 201, 202. The fourth hydraulic fluid path 214 branches to a fifth hydraulic fluid path 215 communicating with the first hydraulic circuit 201 and a sixth hydraulic fluid path 216 communicating with the second hydraulic circuit 202.

The sealing member 115 is provided between the hydraulic piston 114 and the cylinder block 111 and includes a piston sealing member 115a and a drive shaft 133 that seal between the first pressure chamber 112 and the second pressure chamber 113, And a driving shaft sealing member 115b provided between the cylinder block 111 and the second pressure chamber 113 and sealing the opening of the cylinder block 111. [ The hydraulic pressure or negative pressure of the first pressure chamber 112 generated by the forward or backward movement of the hydraulic piston 114 is blocked by the piston sealing member 115a and is not leaked to the second pressure chamber 113, And fourth hydraulic oil passages 211 and 214, respectively. The hydraulic pressure or negative pressure of the second pressure chamber 113 generated by the forward or backward movement of the hydraulic piston 114 may be blocked by the drive shaft sealing member 115b and may not leak to the cylinder block 111. [

The first and second pressure chambers 112 and 113 are connected to the reservoir 30 by the dump passages 116 and 117 so as to receive and store the oil from the reservoir 30, The oil in the chambers 112 and 113 can be transferred to the reservoir 30. For example, the first pressure chamber 112 is connected to the first dump passage 116 through a third communication hole 111c formed on the front side, and the second pressure chamber 113 is connected to the first pressure chamber 112 4 through the communication hole 111d.

Referring again to FIG. 1, the flow paths 211, 212, 213, 214, 215, 216, 217, 218 connected to the first pressure chamber 112 and the second pressure chamber 113 and the valves 231, 232, 233, 234, 235-1, 235-2, 236, 241, 242, 243 will be described.

The second hydraulic oil path 212 may communicate with the first hydraulic circuit 201 and the third hydraulic fluid path 213 may communicate with the second hydraulic circuit 202. [ Therefore, the hydraulic pressure can be transmitted to the first hydraulic circuit 201 and the second hydraulic circuit 202 by advancing the hydraulic piston 114.

A first control valve 231 and a second control valve 232 for controlling the flow of oil may be provided in the second and third hydraulic oil passages 212 and 213, respectively.

The first and second control valves 231 and 232 allow only the oil flow in the direction from the first pressure chamber 112 to the first or second hydraulic circuit 201 and 202 and the oil flow in the opposite direction A check valve may be provided. That is, the first or second control valve 231 or 232 allows the hydraulic pressure of the first pressure chamber 112 to be transmitted to the first or second hydraulic circuit 201 or 202, It is possible to prevent the hydraulic pressure of the circuits 201 and 202 from leaking to the first pressure chamber 112 through the second or third hydraulic oil paths 212 and 213. [

The fifth hydraulic fluid path 215 branched from the fourth hydraulic fluid path 214 communicates with the first hydraulic circuit 201 and the sixth hydraulic fluid path 216 branched from the fourth hydraulic fluid path 214 communicates with the second hydraulic pressure path 214. [ And may be in communication with the circuit 202. Therefore, the hydraulic pressure can be transmitted to both the first hydraulic circuit 201 and the second hydraulic circuit 202 by the backward movement of the hydraulic piston 114. [

A third control valve 233 and a fourth control valve 234 for controlling the flow of oil may be provided in the fifth and sixth hydraulic oil passages 215 and 216, respectively.

The third control valve 233 may be provided as a bidirectional control valve for controlling the flow of oil between the second pressure chamber 113 and the first hydraulic circuit 201. The third control valve 233 may be provided as a solenoid valve of a normal closed type which is normally closed and operates to open the valve when receiving an open signal from the electronic control unit.

The fourth control valve 234 may be provided as a check valve that allows only the oil flow in the direction from the second pressure chamber 113 to the second hydraulic circuit 202 and blocks the oil flow in the opposite direction. That is, the fourth control valve 234 prevents the hydraulic pressure of the second hydraulic circuit 202 from leaking to the second pressure chamber 113 through the sixth hydraulic oil passage 216 and the fourth hydraulic oil passage 214 .

The electromagnetic brake system 1 according to the present embodiment includes a seventh hydraulic oil path 217 connecting the second hydraulic oil path 212 and the third hydraulic oil path 213, And an eighth hydraulic oil path 218 connecting the seventh hydraulic oil path 217 with each other. The seventh hydraulic oil path 217 is provided with a fifth control valve 235 for controlling the flow of bidirectional oil and the eighth hydraulic oil path 218 is provided with a sixth control valve 236 for controlling the flow of bidirectional oil .

The fifth control valve 235 is divided on the basis of the eighth hydraulic oil path 218 connecting the second hydraulic oil path 212 and the seventh hydraulic oil path 217 to the second hydraulic oil path 212, And a fifth-2 control valve 235-2 provided between the third hydraulic oil passage 213 and the eighth hydraulic oil passage 218. The fifth- ).

The 5-1 control valve 235-1 is provided with a check valve that allows the oil flow in the direction from the second hydraulic oil path 212 to the eighth hydraulic oil path 218 but blocks the oil flow in the opposite direction, The 5-2 control valve 235-2 is provided with a check valve that allows the flow of oil in the direction from the third hydraulic oil path 213 to the eighth hydraulic oil path 218 but blocks the flow of oil in the opposite direction .

The sixth control valve 236 may be a normally closed type (Normally Closed type) solenoid valve which is operated to open the valve when it is normally closed and receives an open signal from the electronic control unit. The sixth control valve 236 can be operated to open when the hydraulic pressure of the wheel cylinder 40 is taken out and sent to the first pressure chamber 112. [ This is because the first control valve 231 and the second control valve 232 provided in the second hydraulic oil passage 212 and the third hydraulic oil passage 213 are provided as check valves allowing only one directional oil flow.

The first dump valve 241 provided in the first dump passage 116 for controlling the flow of oil and the second dump valve 242 provided in the second dump passage 117 for controlling the flow of oil are connected to a reservoir 30 to the first or second pressure chambers 112, 113, and closes the opposite direction.

That is, the first dump valve 241 allows the oil to flow from the reservoir 30 to the first pressure chamber 112 while blocking the flow of oil from the first pressure chamber 112 to the reservoir 30 And the second dump valve 242 allows the oil to flow from the reservoir 30 to the second pressure chamber 113 while allowing the oil to flow from the second pressure chamber 113 to the reservoir 30, The flow can be a blocking check valve.

The second dump passage 117 may include a bypass passage connecting the front end and the rear end of the second dump valve 242. The bypass passage may include a second pressure chamber 113 and a reservoir 30, A third dump valve 243 may be provided to control the oil flow between the first dump valve 241 and the second dump valve 243.

The third dump valve 243 may be provided as a solenoid valve that can control the bidirectional flow of the oil. The third dump valve 243 may be provided with a normally open type solenoid valve that is opened in a normal state and operates to close the valve when receiving a close signal from the electronic control unit.

On the other hand, the electronic brake system 1 according to the present embodiment can operate the hydraulic pressure providing unit 110 in a double-acting manner.

The hydraulic pressure generated in the first pressure chamber 112 while the hydraulic piston 114 advances is transmitted to the first hydraulic circuit 201 through the first hydraulic oil path 211 and the second hydraulic fluid path 212, It is possible to operate the wheel cylinders 40 provided on the rear wheel RL and the right front wheel FR and to transmit the hydraulic oil to the second hydraulic circuit 202 through the first hydraulic fluid path 211 and the third hydraulic fluid path 213 So that the wheel cylinders 40 installed on the left front wheel FL and the right rear wheel RR can be operated.

Similarly, the hydraulic pressure generated in the second pressure chamber 113 while the hydraulic pressure piston 114 is reversed is transmitted to the first hydraulic circuit 201 through the fourth hydraulic oil passage 214 and the fifth hydraulic oil passage 215, It is possible to operate the wheel cylinders 40 provided on the rear wheel RL and the right front wheel FR and to transmit the hydraulic oil to the second hydraulic circuit 202 through the fourth hydraulic fluid passage 214 and the sixth hydraulic fluid passage 216 So that the wheel cylinders 40 installed on the left front wheel FL and the right rear wheel RR can be operated.

The negative pressure generated in the first pressure chamber 112 while the hydraulic piston 114 is retracted is transmitted to the left rear wheel RL and the wheel cylinder 40 provided on the right front wheel FR of the first hydraulic circuit 201 The oil can be sucked and transferred to the first pressure chamber 112 through the second hydraulic oil path 212 and the first hydraulic oil path 211 and the left front wheel FL and the right rear wheel of the second hydraulic circuit 202, The oil in the wheel cylinder 40 installed in the rear wheel RR can be sucked and transferred to the first pressure chamber 112 through the third hydraulic oil path 213 and the first hydraulic oil path 211. [

The negative pressure generated in the second pressure chamber 113 while the hydraulic piston 114 advances sucks the oil of the wheel cylinders 40 of the first hydraulic circuit 201 and the second hydraulic circuit 202, To the second pressure chamber (113) through the second passage (215, 214).

Next, the motor 120 of the hydraulic pressure supply device 100 and the power conversion unit 130 will be described.

The motor 120 is a device for generating a rotational force by a signal output from an electronic control unit (ECU) (not shown), and can generate a rotational force in a forward or reverse direction. The rotational angular velocity and rotational angle of the motor 120 can be precisely controlled. Since the motor 120 is a well-known technology, its detailed description will be omitted.

The electronic control unit includes the valves 120, 121, 222, 222, 222c, 222d, 222c, 222d, 233, 236, and 234 provided in the electromagnetic brake system 1 of the present invention, 243). The operation in which a plurality of valves are controlled according to the displacement of the brake pedal 10 will be described later.

The driving force of the motor 120 causes the displacement of the hydraulic piston 114 through the power conversion unit 130 and the hydraulic pressure generated by the sliding movement of the hydraulic piston 114 in the pressure chamber is transmitted to the hydraulic oil passage 211, To the wheel cylinders 40 provided on the respective wheels RL, FR, FL, RR. A brushless motor comprising a stator 121 and a rotor 122 may be employed as the motor.

The power converting unit 130 is a device for converting the rotational force into a linear motion. The power converting unit 130 may include a worm shaft 131, a worm wheel 132, and a drive shaft 133, for example.

The worm shaft 131 may be formed integrally with the rotation shaft of the motor 120, and is formed with a worm on the outer circumferential surface thereof to be engaged with the worm wheel 132 to rotate the worm wheel 132. The worm wheel 132 is connected to the drive shaft 133 to linearly move the drive shaft 133. The drive shaft 133 is connected to the hydraulic piston 114 to slide the hydraulic piston 114 in the cylinder block 111 .

A signal sensed by the pedal displacement sensor 11 is transmitted to an electronic control unit (ECU) (not shown) while a displacement occurs in the brake pedal 10, The worm shaft 131 is rotated in one direction. The rotational force of the warm shaft 131 is transmitted to the drive shaft 133 via the worm wheel 132 and the hydraulic pressure piston 114 connected to the drive shaft 133 moves forward to generate a hydraulic pressure in the first pressure chamber 112.

On the other hand, when the brake pedal 10 is depressed, the electronic control unit drives the motor 120 in the opposite direction so that the worm shaft 131 rotates in the opposite direction. Accordingly, the worm wheel 132 also rotates in the opposite direction and generates a negative pressure in the first pressure chamber 112 while the hydraulic piston 114 connected to the drive shaft 133 returns (moves backward).

On the other hand, the hydraulic pressure and the negative pressure can be generated in the opposite direction. That is, when a displacement occurs in the brake pedal 10, a signal sensed by the pedal displacement sensor 11 is transmitted to an electronic control unit (ECU) (not shown), and the electronic control unit drives the motor 120 in the opposite direction Thereby rotating the worm shaft 131 in the opposite direction. The rotational force of the warm shaft 131 is transmitted to the drive shaft 133 via the worm wheel 132 and the hydraulic pressure piston 114 connected to the drive shaft 133 moves backward to generate a hydraulic pressure in the second pressure chamber 113.

On the other hand, when the pressing force is removed from the brake pedal 10, the electronic control unit drives the motor 120 in one direction so that the worm shaft 131 rotates in one direction. Accordingly, the worm wheel 132 also rotates in the opposite direction and generates a negative pressure in the second pressure chamber 113 while the hydraulic piston 114 connected to the drive shaft 133 returns (advances).

The hydraulic pressure supply device 100 transfers the hydraulic pressure to the wheel cylinder 40 or sucks the hydraulic pressure to the reservoir 30 according to the rotational direction of the rotational force generated from the motor 120. For example, when the motor 120 rotates in one direction, a hydraulic pressure may be generated in the first pressure chamber 112 or a negative pressure may be generated in the second pressure chamber 113. The hydraulic pressure may be used for braking or using a negative pressure Whether to release the braking can be determined by controlling the valves 54, 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 233, 236, 243.

On the other hand, the electronic brake system 1 according to the present embodiment includes first and second backup oil passages 251 and 252 capable of supplying the oil discharged from the master cylinder 20 directly to the wheel cylinder 40 at the time of abnormal operation ).

The first backup hydraulic passage 251 connects the first hydraulic pressure port 24a and the first hydraulic pressure circuit 201 and the second backup hydraulic passage 252 connects the second hydraulic pressure port 24b and the second hydraulic pressure circuit 202, Can be connected. A first cut valve 261 for controlling the flow of bidirectional oil is provided in the first backup passage 251 and a second cut valve 262 is provided in the second backup passage 252 for controlling the flow of bidirectional oil. .

The first and second cut valves 261 and 262 may be provided with a normally open type solenoid valve that is opened in a normal state and operates to close the valve when receiving a close signal from the electronic control unit .

Next, the hydraulic control unit 200 according to the embodiment of the present invention will be described.

The hydraulic control unit 200 may include a first hydraulic circuit 201 and a second hydraulic circuit 202 so as to be able to receive and control two wheels, respectively, by receiving hydraulic pressure. For example, the first hydraulic circuit 201 may control the left rear wheel RL and the right front wheel FR and the second hydraulic circuit 202 may control the left front wheel FL and the right rear wheel RR . The wheel cylinders 40 are provided on the respective wheels RL, FR, FL and RR to supply hydraulic pressure from the hydraulic pressure supply device 100 to perform braking.

The first hydraulic circuit 201 is connected to the first hydraulic oil path 211 and the second hydraulic oil path 212 to receive the hydraulic pressure from the hydraulic pressure supply device 100. The second hydraulic oil path 212 is connected to the left rear wheel RL ) And the right front wheel (FR). Similarly, the second hydraulic circuit 202 is connected to the first hydraulic oil path 211 and the third hydraulic oil path 213 to receive the hydraulic pressure from the hydraulic pressure supply device 100, and the third hydraulic oil path 213 is connected to the left front wheel (FL) and the right rear wheel (RR). The fifth hydraulic fluid path 215 connected to the second hydraulic fluid path 212 and the sixth hydraulic fluid path 216 connected to the third hydraulic fluid path 213 are branched and connected to each wheel cylinder 40 as well.

The first and second hydraulic circuits 201 and 202 may have a plurality of inlet valves 221 (221a, 221b, 221c and 221d) to control the flow of hydraulic pressure. For example, the first hydraulic circuit 201 may be provided with two inlet valves 221a and 221b connected to the first hydraulic oil path 211 to control the hydraulic pressures transmitted to the two wheel cylinders 40 . The second hydraulic circuit 202 may be provided with two inlet valves 221c and 221d which are connected to the third hydraulic fluid path 213 and control the hydraulic pressure transmitted to the wheel cylinder 40, respectively. Here, the inlet valve 221 is disposed on the upstream side of the wheel cylinder 40, is open in a normal state, and is operated in a normally open type solenoid operated to close the valve when receiving a closing signal from the electronic control unit Valve.

The first and second hydraulic circuits 201 and 202 are provided with check valves 223a, 223b, 223c and 223d provided in a bypass flow passage connecting the inlet valves 221a, 221b, 221c and 221d, . ≪ / RTI > The check valves 223a, 223b, 223c and 223d allow only the flow of oil from the wheel cylinder 40 toward the hydraulic pressure providing unit 110 and the oil from the hydraulic pressure providing unit 110 to the wheel cylinder 40 May be provided to limit the flow. The check valves 223a, 223b, 223c and 223d can quickly release the braking pressure of the wheel cylinders 40. When the inlet valves 221a, 221b, 221c and 221d are not operated normally, So that the hydraulic pressure of the hydraulic pump 40 can be introduced into the hydraulic pressure providing unit 110.

The first and second hydraulic circuits 201 and 202 may further include a plurality of outlet valves 222 (222a, 222b, 222c and 222d) connected to the reservoir 30 in order to improve the braking performance. The outlet valve 222 is connected to the wheel cylinder 40 to control the fluid pressure to escape from each of the wheels FL, RR, RL and FR. That is, the outlet valve 222 senses the braking pressure of each of the wheels RL, FR, FL and RR and is selectively opened to control the pressure when the pressure reduction braking is required. The outlet valve 222 may be a normally closed type (Normally Closed type) solenoid valve which is operated to open the valve when it is normally closed and receives an open signal from the electronic control unit.

On the other hand, the hydraulic control unit 200 can be connected to the backup channels 251 and 252. For example, the first hydraulic circuit 201 is connected to the first backup channel 251 to receive the hydraulic pressure from the master cylinder 20, and the second hydraulic circuit 202 is connected to the second backup channel 252 The hydraulic pressure can be supplied from the master cylinder 20.

The first backup oil passage 251 can join the first hydraulic circuit 201 downstream of the first and second inlet valves 221a and 221b. Similarly, the second backup oil passage 252 can join the second hydraulic circuit 202 downstream of the third and fourth inlet valves 221c and 221d. Therefore, when the first and second cut valves 261 and 262 are closed, the hydraulic pressure provided by the hydraulic pressure supply device 100 is supplied to the wheel cylinder 40 through the first and second hydraulic circuits 201 and 202 And when the first and second cut valves 261 and 262 are opened, the hydraulic pressure provided by the master cylinder 20 is quickly transmitted to the wheel cylinder 40 through the first and second backup oil channels 251 and 252 . At this time, since the plurality of inlet valves 221a, 221b, 221c, and 221d are kept open, there is no need to switch the operation state.

PS2 is a pressure sensor for sensing the hydraulic pressure of the first or second hydraulic circuits 201 and 202 and PS2 is a hydraulic pressure sensor for detecting the hydraulic pressure of the master cylinder 20. [ It is a pressure sensor. "MPS" is a motor control sensor that controls the rotation angle of the motor 120 or the current of the motor.

Hereinafter, the braking operation of the electronic brake system 1 according to the embodiment of the present invention will be described in detail.

Prior to the description, the hydraulic pressure supply apparatus 100 of the present embodiment The low-pressure mode and the high-pressure mode can be used separately. The low pressure mode and the high pressure mode can be changed by changing the operation of the hydraulic control unit 200. The hydraulic pressure supply device 100 can generate a high hydraulic pressure without increasing the output of the motor 120 by using the high pressure mode. Therefore, it is possible to secure stable braking power while lowering the price and weight of the brake system.

More specifically, the hydraulic piston 114 generates hydraulic pressure in the first pressure chamber 112 while advancing. The amount of oil transferred from the first pressure chamber 112 to the wheel cylinder 40 increases as the hydraulic piston 114 advances in the initial state, that is, as the stroke of the hydraulic piston 114 increases, do. However, since there is an effective stroke of the hydraulic piston 114, there is a maximum pressure due to the advance of the hydraulic piston 114. [

The maximum pressure in the low pressure mode is less than the maximum pressure in the high pressure mode. However, the pressure increase rate per stroke of the hydraulic piston 114 is small in the high pressure mode as compared with the low pressure mode. This is because not all of the oil pushed out of the first pressure chamber 112 flows into the second pressure chamber 113 but flows into the wheel cylinder 40.

Therefore, it is possible to use a low-pressure mode in which the rate of pressure increase per stroke is high at the early stage of braking in which the braking response is important, and a high-pressure mode in which the maximum braking force is important.

Fig. 5 is a hydraulic circuit diagram showing a situation in which the hydraulic piston advances while providing a braking pressure in a low pressure mode, and Fig. 6 is a hydraulic circuit diagram showing a situation in which the hydraulic piston advances and braking pressure is provided in a high pressure mode.

When the braking by the driver is started, the amount of brake demand of the driver can be sensed through the pedal displacement sensor 11 through information such as the pressure of the brake pedal 10 depressed by the driver. An electronic control unit (not shown) receives the electrical signal output from the pedal displacement sensor 11 and drives the motor 120.

The electronic control unit includes a backup hydraulic pressure sensor PS1 provided at the outlet side of the master cylinder 20 and a hydraulic pressure sensor PS2 provided at the second hydraulic circuit 202 (or the first hydraulic circuit 201) And the magnitude of the frictional braking amount is calculated according to the difference between the demand braking amount and the regenerating braking amount of the driver to determine the magnitude of the pressure increase or the pressure decrease of the wheel cylinder 40. [

5, when the driver depresses the brake pedal 10 at the beginning of braking, the motor 120 rotates in one direction, and the rotational force of the motor 120 is transmitted to the hydraulic pressure providing unit 110, and the hydraulic pressure providing unit 110 generates hydraulic pressure in the first pressure chamber 112 while the hydraulic piston 114 advances. The hydraulic pressure discharged from the hydraulic pressure providing unit 110 is transmitted to the wheel cylinders 40 provided on the four wheels through the first hydraulic circuit 201 and the second hydraulic circuit 202 to generate the braking force.

Specifically, the hydraulic pressure provided in the first pressure chamber 112 is transmitted to the two wheels RL and FR through the first hydraulic oil passage 211 and the second hydraulic oil passage 212, which are connected to the first communication hole 111a. To the wheel cylinder 40 provided in the wheel cylinder 40. At this time, the first and second inlet valves 221a and 221b installed in the two flow paths branched from the second hydraulic oil path 212 are provided in an open state. In addition, the first and second outlet valves 222a and 222b provided in the flow paths branched respectively from the two hydraulic fluid paths branched from the second hydraulic fluid path 212 are kept closed to leak hydraulic pressure to the reservoir 30 Stop.

The hydraulic pressure provided in the first pressure chamber 112 is transmitted to the two wheels FL and RR through the first hydraulic oil passage 211 and the third hydraulic oil passage 213 connected to the first communication hole 111a And is directly transmitted to the wheel cylinder 40 provided. At this time, the third and fourth inlet valves 221c and 221d, which are respectively installed in the two flow paths branched from the third hydraulic oil path 213, are opened. The third and fourth outlet valves 222c and 222d provided in the flow paths branched from the two hydraulic flow paths branched from the third hydraulic fluid path 213 are kept closed to leak hydraulic pressure to the reservoir 30 Stop.

At this time, the sixth control valve 236 maintains the open state and the seventh hydraulic oil path 217, the eighth hydraulic oil path 218 connecting the seventh hydraulic oil path 217 and the second hydraulic fluid path 212, Can be opened. However, the oil flowing from the seventh hydraulic oil path 217 to the eighth hydraulic oil path 218 is circulated by the fifth hydraulic control valve 235-1 and the fifth hydraulic control valve 235-2, (Not shown). Here, the sixth control valve 236 may be switched from the open state to the closed state if necessary.

At this time, the third control valve 233 may be kept closed to shut off the fifth hydraulic oil path 215. Accordingly, the hydraulic pressure generated in the first pressure chamber 112 can not be transferred to the second pressure chamber 113 through the fifth hydraulic oil passage 215, so that the rate of pressure increase per stroke can be improved. Therefore, a quick braking response can be expected at the beginning of braking.

Further, when the pressure to be transmitted to the wheel cylinder 40 is measured to be higher than the target pressure value in accordance with the pressing force of the brake pedal 10, the electronic control unit controls at least any one of the first to fourth outlet valves 222 The hydraulic pressure can be controlled so as to follow the target pressure value.

The first and second hydraulic oil passages 251 and 252 connected to the first and second hydraulic ports 24a and 24b of the master cylinder 20 generate hydraulic pressure in the hydraulic pressure supply device 100, The second cut valves 261 and 262 are closed so that the hydraulic pressure discharged from the master cylinder 20 is not transmitted to the wheel cylinder 40.

The pressure generated in response to the pressing force of the brake pedal 10 in accordance with the pressure of the master cylinder 20 is transmitted to the simulation apparatus 50 connected to the master cylinder 20. [ At this time, the normally closed simulator valve 54 disposed at the rear end of the simulation chamber 51 is opened, and the oil filled in the simulation chamber 51 through the simulator valve 54 is transferred to the reservoir 30. Further, a pressure corresponding to the load of the reaction force spring 53, in which the reaction force piston 52 moves and which supports the reaction force piston 52, is formed in the simulation chamber 51 to provide a proper pedal feeling to the driver.

The pressure sensor PS1 with the hydraulic oil installed in the third hydraulic oil path 213 can detect the flow rate delivered to the left front wheel FL or the wheel cylinder 40 provided at the right rear wheel RR. Therefore, the electronic control unit can control the flow rate to be transmitted to the wheel cylinder 40 by controlling the hydraulic pressure supply device 100 in accordance with the output of the pressure sensor PS1 with the hydraulic oil. Specifically, the flow rate and discharge speed of the wheel cylinder 40 can be controlled by controlling the advance distance and the advance speed of the hydraulic piston 114.

On the other hand, the hydraulic pressure supply device 100 can switch from the low-pressure mode shown in Fig. 5 to the high-pressure mode shown in Fig. 6 before the hydraulic piston 114 advances to the maximum.

Referring to FIG. 6, in the high pressure mode, the third control valve 233 may be opened to open the fifth hydraulic oil path 215. The hydraulic pressure generated in the first pressure chamber 112 is transmitted to the second pressure chamber 113 through the second hydraulic oil passage 212 and the fifth hydraulic oil passage 215 and can be used to push out the hydraulic piston 114 have.

In the high pressure mode, a part of the oil pushed out of the first pressure chamber 112 flows into the second pressure chamber 113, so that the rate of pressure increase per stroke decreases. However, since a part of the hydraulic pressure generated in the first pressure chamber 112 is used to push out the hydraulic piston 114, the maximum pressure is increased. At this time, the maximum pressure is increased because the volume per stroke of the hydraulic piston 114 of the second pressure chamber 113 is smaller than the volume per stroke of the hydraulic piston 114 of the first pressure chamber 112.

At this time, the third dump valve 243 can be switched to the closed state. By closing the third dump valve 243, the oil in the first pressure chamber 112 can be rapidly introduced into the second pressure chamber 113 in the negative pressure state. However, in some cases, the third dump valve 243 is kept open so that the oil in the second pressure chamber 113 may flow into the reservoir 30.

7 is a hydraulic circuit diagram showing a situation in which the hydraulic piston 114 provides a braking pressure while reversing.

7, when the driver depresses the brake pedal 10 at the initial stage of braking, the motor 120 is operated to rotate in the opposite direction, and the rotational force of the motor 120 is transmitted to the hydraulic pressure supply unit 130 by the power transmission unit 130. [ And the hydraulic pressure piston 114 of the hydraulic pressure providing unit 110 moves backward to generate the hydraulic pressure in the second pressure chamber 113. [ The hydraulic pressure discharged from the hydraulic pressure providing unit 110 is transmitted to the wheel cylinders 40 provided on the four wheels through the first hydraulic circuit 201 and the second hydraulic circuit 202 to generate the braking force.

Specifically, the hydraulic pressure provided in the second pressure chamber 113 passes through the fourth hydraulic oil passage 214 connected to the second communication hole 111b and the opened fifth hydraulic oil passage 215, And is transmitted to the wheel cylinders 40 provided on the two wheels RL and FR through the second hydraulic fluid passage 212 connected to the second hydraulic oil passage 215. At this time, the sixth control valve 236 provided in the eighth hydraulic oil path 218 maintains the closed state, the first and second inlet valves 221a and 221b are provided in an open state, and the first and second The outlet valves 222a and 222b are kept closed to prevent the liquid pressure from leaking to the reservoir 30.

The hydraulic pressure provided in the second pressure chamber 113 passes through the fourth hydraulic oil passage 214 and the sixth hydraulic oil passage 216 connected to the second communication hole 111b and is supplied to the sixth hydraulic oil passage 216, And is transmitted to the wheel cylinders 40 provided on the two wheels FL and RR through the third hydraulic oil path 213 connected to the wheel cylinders. At this time, the sixth control valve 236 provided in the eighth hydraulic oil path 218 maintains the closed state, the third and fourth inlet valves 221c and 221d are provided in the open state, and the third and fourth The outlet valves 222c and 222d are kept closed to prevent the hydraulic pressure from leaking to the reservoir 30.

The third control valve 233 is switched from the closed state to the open state to open the fifth hydraulic oil path 215 while the fourth control valve 234 is closed The second hydraulic oil passage 216 is also opened because it is provided as a check valve allowing the hydraulic pressure in the direction of the wheel cylinder 40 in the second pressure chamber 113 to be transmitted. Further, the sixth control valve 236 is kept closed to shut off the eighth hydraulic oil path 218. Accordingly, since the hydraulic pressure generated in the second pressure chamber 113 can not be transferred to the first pressure chamber 112 through the eighth hydraulic oil path 218, the rate of pressure increase per stroke can be improved, Can be expected.

At this time, the third dump valve 243 can be switched to the closed state. The third dump valve 243 is closed so that the oil in the second pressure chamber 113 can be quickly discharged through the fourth hydraulic oil passage 214. [

Next, a description will be made of a case where the braking force is released in the braking state in the normal operation of the electromagnetic brake system 1 according to the present embodiment.

Fig. 8 is a hydraulic circuit diagram showing a situation in which the hydraulic pressure piston 114 is released while releasing the braking pressure in the high pressure mode while Fig. 9 is a hydraulic pressure circuit diagram showing a situation in which the hydraulic pressure piston 114 is reversed and the braking pressure is released in the low pressure mode.

8, when the pedal force applied to the brake pedal 10 is released, the motor 120 generates a rotational force in a direction opposite to the braking state and transmits the rotational force to the power conversion unit 130, The shaft 131, the worm wheel 132 and the drive shaft 133 are rotated in the opposite direction to rotate the hydraulic piston 114 back to the original position to release the pressure in the first pressure chamber 112 . The hydraulic pressure providing unit 110 receives the hydraulic pressure discharged from the wheel cylinder 40 through the first and second hydraulic circuits 201 and 202 and transfers the hydraulic pressure to the first pressure chamber 112.

The negative pressure generated in the first pressure chamber 112 is supplied to the first hydraulic oil passage 211 and the second hydraulic oil passage 212 connected to the first communication hole 111a and the second hydraulic oil passage 212 connected to the sixth control valve 236 The pressure of the wheel cylinders 40 provided on the two wheels RL and FR through the seventh hydraulic oil passage 217 and the eighth hydraulic oil passage 218 communicating with the second hydraulic oil passage 212 due to the opening change Release. At this time, the first and second inlet valves 221a and 221b, which are respectively installed in two flow paths branched from the second hydraulic oil path 212, are opened, and the first and second outlet valves 222a and 222b And is kept closed to prevent the oil of the reservoir 30 from being introduced.

The negative pressure generated in the first pressure chamber 112 is transmitted through the first hydraulic oil passage 211 and the third hydraulic oil passage 213 connected to the first communication hole 111a and the opening of the sixth control valve 236 The pressure of the wheel cylinders 40 provided on the two wheels FL and RR is released through the seventh hydraulic oil path 217 and the eighth hydraulic oil path 218 communicating with the third hydraulic oil path 213 due to the switching. do. At this time, the third and fourth inlet valves 221c and 221d, which are respectively installed in two flow paths branched from the third hydraulic oil path 213, are opened, and the third and fourth outlet valves 222c and 222d And is kept closed to prevent the oil of the reservoir 30 from being introduced.

On the other hand, in the high pressure mode, the third control valve 233 is switched to the open state to open the fifth hydraulic oil path 215, and the 5-1 control valve 235-1 is opened in the second pressure chamber 113 1 pressure chamber 112 and the sixth control valve 236 is opened and the eighth hydraulic oil path 218 can be opened. The fifth hydraulic fluid passage 215, the seventh hydraulic fluid passage 217 and the eighth hydraulic fluid passage 218 are connected to each other so that the first pressure chamber 112 and the second pressure chamber 113 communicate with each other.

In order to form a negative pressure in the first pressure chamber 112, the hydraulic piston 114 must move backward. When the second pressure chamber 113 is full of oil, the hydraulic piston 114 is moved backward to generate a resistance . The third control valve 233 and the sixth control valve 236 are opened and the fourth hydraulic fluid path 214, the fifth hydraulic fluid path 215, the second hydraulic fluid path 212 and the first hydraulic fluid path 211, The oil in the second pressure chamber 113 can be moved to the first pressure chamber 112. [

At this time, the third dump valve 243 can be switched to the closed state. The third dump valve 243 is closed so that the oil in the second pressure chamber 113 can be discharged only to the fourth hydraulic oil passage 214. [ However, in some cases, the third dump valve 243 is kept open so that the oil in the second pressure chamber 113 may flow into the reservoir 30.

Further, when the negative pressure transmitted to the first and second hydraulic circuits 201 and 202 is measured to be higher than the target pressure release value according to the release amount of the brake pedal 10, It is possible to control at least one of the valve 222 and the valve 222 to follow the target pressure value.

The first and second hydraulic oil passages 251 and 252 connected to the first and second hydraulic ports 24a and 24b of the master cylinder 20 generate hydraulic pressure in the hydraulic pressure supply device 100, The second cut valves 261 and 262 are closed so that the negative pressure generated in the master cylinder 20 is not transmitted to the hydraulic control unit 200.

In the high pressure mode shown in Fig. 8, the oil in the second pressure chamber 113, together with the oil in the wheel cylinder 40, is discharged by the negative pressure in the first pressure chamber 112 generated while the hydraulic piston 114 moves backward, The pressure reduction rate of the wheel cylinder 40 is small because it moves to the pressure chamber 112. Therefore, it may be difficult to release the pressure quickly in the high pressure mode.

For this reason, the high-pressure mode can be used only in a high-pressure state, and can be switched to the low-pressure mode shown in FIG. 9 when the pressure is lowered to a certain level or lower.

9, in the low pressure mode, the third control valve 233 is maintained or switched closed so that the third dump valve 243 is switched or maintained in the opened state instead of closing the fifth hydraulic fluid path 215 The second pressure chamber 113 can be connected to the reservoir 30.

In the low pressure mode, since the negative pressure generated in the first pressure chamber 112 is used only to suck the oil stored in the wheel cylinder 40, the pressure decrease rate per stroke of the hydraulic piston 114 increases as compared with the high pressure mode. The liquid pressure generated in the second pressure chamber 113 is supplied to the reservoir 30 at atmospheric pressure through the third dump valve 243 which is opened rather than passing through the fourth control valve 234 provided as a check valve Most go out.

Although not shown in the drawing, the braking pressure release of the wheel cylinder 40 in the low-pressure mode and the high-pressure mode when the hydraulic piston 114 moves in the opposite direction, that is, in the reverse direction, 214, 215, 216, 217, 218 and the valves 231, 232, 233, 234, 235-1, 235-2, 236, 241, 242, 243, It is possible to easily control by generating the hydraulic pressure and the negative pressure in the two pressure chambers 113, respectively.

Although the operation of the electronic braking system that normally brakes and releases the braking operation has been described above, the present invention is not limited thereto, and the braking operation in the abnormal state, the ABS mode, the dump mode, 232, 213, 214, 215, 216, 217, 218 connected to the first pressure chamber 112 and the second pressure chamber 113 and the valves 231, 232, 233, 234, 235-1, 235-2, 236, 241, 242, 243).

10 is a hydraulic circuit diagram showing a state in which the electronic brake system 1 according to the embodiment of the present invention is operated in the inspection mode.

When the electromagnetic brake system 1 is operating abnormally, each of the valves 54, 221a, 221b, 221c, 221d, 222a, 222b, 222c, 222d, 233, 236, 243 is set in a non- Of the wheel cylinders 40 provided on the first and second cut valves 261 and 262 and the wheels FL, RR, RL, and FR provided on the first and second backup oil channels 251 and 252, The inlet valve 221 is opened and the hydraulic pressure is transmitted to the wheel cylinder 40 immediately.

The simulator valve 54 is provided in a closed state to prevent the hydraulic pressure transmitted to the wheel cylinder 40 through the first backup channel 251 from leaking to the reservoir 30 through the simulation device 50. Therefore, when the driver depresses the brake pedal 10, the hydraulic pressure discharged from the master cylinder 20 is transferred to the wheel cylinder 40 without loss, thereby ensuring stable braking.

However, when a leak occurs in the simulator valve 54, part of the hydraulic pressure discharged from the master cylinder 20 may be lost to the reservoir 30 through the simulator valve 54. [ The simulator valve 54 is provided to be closed in the abnormal mode. The hydraulic pressure discharged from the master cylinder 20 pushes the reaction force piston 52 of the simulation apparatus 50, The simulator valve 54 may leak.

In this way, when leakage occurs in the simulator valve 54, the driver does not obtain the intended braking force. Therefore, there is a problem in braking stability.

The inspection mode is a mode for checking whether a pressure is lost by generating a hydraulic pressure in the hydraulic pressure supply device 100 to check whether the simulator valve 54 is leaking. If the hydraulic pressure discharged from the hydraulic pressure supply device 100 flows into the reservoir 30 and pressure loss occurs, it is difficult to know whether or not the simulator valve 54 has leaked.

therefore. In the inspection mode, as shown in FIG. 10, the hydraulic circuit connected to the hydraulic pressure supply device 100 by closing the simulator valve 54, which is an electromagnetic opening / closing valve, can be constituted by a closed circuit. That is, by keeping the simulator valve 54 and the outlet valve 222 in a closed state, the flow path connecting the hydraulic pressure supply device 100 and the reservoir 30 can be blocked to constitute a closed circuit.

Also, in the inspection mode, the hydraulic pressure can be supplied only to the first backup passage 251 to which the simulation apparatus 50 is connected, among the first and second backup passages 251 and 252. Therefore, in order to prevent the hydraulic pressure discharged from the hydraulic pressure supply device 100 from being transmitted to the master cylinder 20 along the second backup channel 252, the second cut valve 262 is switched to the closed state in the inspection mode . The third control valve 233 for connecting the first hydraulic circuit 201 and the second hydraulic circuit 202 is kept closed and the sixth control valve 236 is closed to close the second pressure chamber 113 Can be prevented from leaking to the first pressure chamber 112.

In the inspection mode, the electronic control unit analyzes the signal transmitted from the back-flow passage pressure sensor PS2 that measures the oil pressure of the master cylinder 20 after generating the hydraulic pressure in the hydraulic pressure supply device 100, It is possible to detect a state in which leakage occurs. For example, when there is no loss in the result of the measurement of the backup hydraulic pressure sensor PS2, it is determined that there is no leakage of the simulator valve 54, and when a loss occurs, it is determined that there is a leak in the simulator valve 54 .

11 shows a hydraulic pressure supply apparatus for an electronic brake system according to another embodiment of the present invention. The present embodiment will be described mainly on the points different from the above embodiment, and the same reference numerals denote the same functions, and a detailed description thereof will be omitted.

The hydraulic pressure supply apparatus 100 according to the present embodiment includes a hydraulic pressure providing unit 110 for providing oil pressure to be transmitted to the wheel cylinder 40 and a motor for generating a rotational force by an electrical signal of the pedal displacement sensor 11 And a power converting unit 130 that converts the rotational motion of the motor 120 into a rectilinear motion and transmits the rectilinear motion to the hydraulic pressure providing unit 110.

The hydraulic pressure providing unit 110 may include a first pressure chamber 112 located in front of the hydraulic piston 114 and a second pressure chamber 113 located in the rear of the hydraulic piston 114 .

The first pressure chamber 112 is connected to the first and second hydraulic circuits 201 and 202 using the first hydraulic oil path 211 and the second pressure chamber 113 is connected to the fourth hydraulic oil path 214 And is connected to the first and second hydraulic circuits (201, 202).

The second hydraulic oil path 212 branched from the first hydraulic oil path 211 communicates with the first hydraulic circuit 201 and the third hydraulic fluid path 213 can communicate with the second hydraulic circuit 202 And a first control valve 231 and a second control valve 232 in the form of a check valve may be provided in the second and third hydraulic oil passages 212 and 213.

The fifth hydraulic oil path 215 branched from the fourth hydraulic oil path 214 communicates with the first hydraulic circuit 201 and the sixth hydraulic fluid path 216 can communicate with the second hydraulic circuit 202 And a third control valve 233 'and a fourth control valve 234 in the form of a check valve may be provided on the fifth and sixth hydraulic oil passages 215 and 216, respectively.

The first to fourth control valves 231, 232, 233 ', and 234 provided in the form of a check valve can supply hydraulic pressure from the hydraulic pressure providing unit 110 to the wheel cylinder 40, but when the pressure in the wheel cylinder 40 is required Even if the negative pressure is generated in the hydraulic pressure providing unit 110, the oil does not move. Therefore, in the electronic brake system, the wheel cylinder 40 can be controlled to be reduced in pressure by using the outlet valves 222 (222a, 222b, 222c, 222d).

Meanwhile, although not shown in the drawings, the electromagnetic brake system according to the present invention may not include the sixth hydraulic oil passage 216. The electronic brake system not including the sixth hydraulic oil passage 216 can generate the hydraulic pressure and the negative pressure only when the hydraulic piston 114 advances, so that it can be applied and controlled in a simpler form to the required vehicle.

10: Brake pedal 11: Pedal displacement sensor
20: master cylinder 30: reservoir
31-33: reservoir chamber 34,35: partition wall
40: Wheel cylinder 50: Simulation device
54: simulator valve (electromagnetic opening / closing valve) 55: check valve
100: hydraulic pressure supply device 110: hydraulic pressure supply unit
120: motor 130: power conversion unit
200: Hydraulic control unit 201: First hydraulic circuit
202: second hydraulic circuit 211: first hydraulic oil
212: second hydraulic oil passage 213: third hydraulic oil passage
214: fourth hydraulic oil rail 215: fifth hydraulic oil rail
216: sixth hydraulic oil 217: seventh hydraulic oil
218: Eighth hydraulic oil passage 221: Inlet valve
222: outlet valve 223: check valve
231: first control valve 232: second control valve
233, 233 ': third control valve 234: fourth control valve
235, 235-1, 235-2: fifth control valve 236: sixth control valve
241: first dump valve 242: second dump valve
243: Third dump valve 251: First backup channel
252: second backup passage 261: first cut valve
262: Second cut valve PS1: Hydraulic oil pressure sensor
MPS: Motor control sensor

Claims (9)

A hydraulic cylinder which is provided at one side of the hydraulic piston and which is movably accommodated in the cylinder block to generate a hydraulic pressure using a hydraulic piston operated by an electrical signal outputted in response to a displacement of the brake pedal, A hydraulic pressure supply device including a pressure chamber and a second pressure chamber provided on the other side of the hydraulic piston and connected to at least one wheel cylinder;
A first hydraulic oil communicating with the first pressure chamber;
A second hydraulic oil branching from the first hydraulic oil passage;
A third hydraulic oil branching from the first hydraulic oil passage;
A fourth hydraulic oil communicating with the second pressure chamber;
A fifth hydraulic oil branching from the fourth hydraulic oil passage and joining to the second hydraulic oil passage;
A sixth hydraulic oil branching from the fourth hydraulic oil passage and joining to the third hydraulic oil passage;
A seventh hydraulic oil connecting the second hydraulic oil passage and the third hydraulic oil passage;
An eighth hydraulic oil connecting the second hydraulic oil passage and the seventh hydraulic oil passage;
A first control valve provided in the second hydraulic oil passage for controlling the flow of oil;
A second control valve provided in the third hydraulic oil passage to control the flow of oil;
A third control valve provided in the fifth hydraulic oil passage and controlling the flow of the oil;
A fourth control valve provided in the sixth hydraulic oil passage for controlling the flow of oil;
A fifth control valve provided in the seventh hydraulic oil passage for controlling the flow of oil;
A sixth control valve provided in the eighth hydraulic oil passage for controlling the flow of oil;
A first hydraulic circuit that is connected to the two wheel cylinders in the second hydraulic oil passage or the fifth hydraulic oil passage, respectively; And
And a second hydraulic circuit that is connected to the two wheel cylinders in the third hydraulic fluid passage or the sixth hydraulic fluid passage,
Wherein the first control valve and the second control valve are provided as check valves which permit the flow of oil in the direction from the hydraulic pressure supply device to the wheel cylinder and block the flow of oil in the opposite direction,
The fourth control valve is provided with a check valve which allows the flow of oil in the direction from the hydraulic pressure supply device to the wheel cylinder and blocks the flow of oil in the opposite direction,
The fifth control valve includes a fifth control valve provided between the second hydraulic oil passage and the eighth hydraulic oil passage and a fifth control valve provided between the third hydraulic oil passage and the eighth hydraulic oil passage And the 5-1 control valve is provided as a check valve that allows the flow of oil in the direction from the second hydraulic oil path to the eighth hydraulic oil path and blocks the flow of oil in the opposite direction, A check valve for allowing the flow of the oil in the direction from the third hydraulic oil path to the eighth hydraulic oil path to be blocked but blocking the flow of the oil in the opposite direction,
Said sixth control valve being provided as a solenoid valve capable of controlling bi-directional flow. The method according to claim 1,
Wherein the third control valve is provided as a solenoid valve capable of controlling bi-directional flow. 3. The method of claim 2,
And the third control valve is provided in a normally closed type. The method according to claim 1,
Wherein the third control valve is provided with a check valve that allows the flow of oil in the direction from the hydraulic pressure supply to the wheel cylinder, but blocks the flow of oil in the opposite direction. 5. The method according to any one of claims 1 to 4,
A reservoir in which the oil is stored;
A master cylinder connected to the reservoir;
Further comprising a simulation device for providing a reaction force corresponding to the power of the brake pedal by using the oil flowing out from the master cylinder,
A check valve provided in a reservoir passage for connecting the reservoir and the master cylinder to the simulation apparatus and allowing only a fluid flow from the reservoir to the master cylinder,
A bypass flow path connecting the front and rear sides of the check valve; and a solenoid valve provided to control the bidirectional flow to the bypass flow path. 6. The method of claim 5,
Wherein the solenoid valve is provided in a normally closed type. The method according to claim 1,
Further comprising a reservoir in which the oil is stored,
A first dump passage communicating with the first pressure chamber and connected to the reservoir,
A second dump passage communicating with the second pressure chamber and connected to the reservoir,
The first dump passage being provided in the first dump passage to control the flow of the oil while allowing the flow of oil in the direction from the reservoir to the first pressure chamber while blocking the flow of oil in the opposite direction, A valve,
And a second dump provided in the second dump passage to control the flow of the oil while allowing the flow of oil in the direction from the reservoir to the second pressure chamber while blocking the flow of oil in the opposite direction, A valve,
And a second dump valve for controlling the flow of oil in both directions between the reservoir and the second pressure chamber, And a third dump valve provided as a solenoid valve. The method according to claim 1,
Further comprising a reservoir in which the oil is stored,
The reservoir includes a first reservoir chamber connected to recover oil dumped from the first hydraulic circuit, a second reservoir chamber connected to supply oil to the hydraulic pressure supply device, Said first reservoir chamber and said third reservoir chamber being separated from each other, wherein said first reservoir chamber and said third reservoir chamber are separated from each other. 9. The method of claim 8,
Wherein the second reservoir chamber is separate from the first reservoir chamber and the third reservoir chamber.

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