Electric hydraulic brake

Abstract

The present disclosure relates to an electro-hydraulic brake. The electro-hydraulic brake includes: a wheel brake configured to supply a braking force to a wheel of a vehicle; a reservoir storing brake fluid; a master cylinder connected to the reservoir and operating in cooperation with a main brake motor to generate a pressure of the brake fluid; a first controller configured to control the main brake motor; a hydraulic controller including a pump and a hydraulic block, the pump being configured to form a pressure of the brake fluid in cooperation with an auxiliary brake motor, the hydraulic block being configured to selectively transmit the pressure of the brake fluid formed in the master cylinder or the pump to the wheel brake; and a second controller configured to control the auxiliary brake motor when a failure occurs in the master cylinder or the first controller. The hydraulic controller is provided with an auxiliary flow path to directly transmit the brake fluid from the reservoir to the pump through the auxiliary flow path.

Description

Technical Field

[0001] The present disclosure relates to an electro-hydraulic brake. Background Art

[0002] The content described in this section only provides background information on the present disclosure and does not constitute prior art.

[0003] An electro-hydraulic brake uses an electric motor to generate hydraulic pressure and transmits the hydraulic pressure to wheel cylinders to generate braking force in each wheel cylinder. The electro-hydraulic brake makes it easy to individually control the braking force generated in each wheel brake, enabling functions such as an electronic stability control (ESC) system or an anti-lock braking system (ABS) to be easily implemented.

[0004] ESC is designed to stably maintain the attitude of a vehicle when the attitude of the vehicle is unstable during driving. The causes of an unstable attitude of the vehicle include road conditions with a slippery road surface due to rain, snow, or sand, and motion inertia such as sudden zigzag driving. The ESC system controls the torque of the brakes and the engine when the attitude of the vehicle is in a dangerous state, thereby stably maintaining the attitude of the vehicle.

[0005] When the main braking system does not operate normally, an autonomous vehicle uses an auxiliary braking system provided between the main braking system and multiple wheel brakes to ensure a fail-safe function.

[0006] In the case of adding an auxiliary braking system to the main braking system to achieve redundancy, the layout of the braking system may become complex, and the cost and weight of the entire braking system may increase. Summary of the Invention

[0007] According to at least one embodiment, the present disclosure provides an electro-hydraulic brake, which includes: a plurality of wheel brakes configured to supply braking force to wheels of a vehicle; a reservoir storing brake fluid; a master cylinder connected to the reservoir and cooperating with a main brake motor to generate pressure of the brake fluid; a first controller configured to control the main brake motor according to a braking input; a hydraulic controller including a pump and a hydraulic block, the pump being configured to form pressure of the brake fluid in cooperation with an auxiliary brake motor, the hydraulic block being configured to selectively transfer the pressure of the brake fluid formed in the master cylinder or the pump to the plurality of wheel brakes; and a second controller configured to control the auxiliary brake motor when a failure occurs in the master cylinder or the first controller. The hydraulic controller is provided with at least one auxiliary flow path to directly transfer the brake fluid from the reservoir to the pump through at least one auxiliary flow path. The hydraulic block has a first side and a second side, a plurality of ports connected to the flow path are located in the first side, the auxiliary brake motor is attached to the second side, and at least one side of the hydraulic block is coupled to the master cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0009] Figure 2 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0010] Figure 3 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0011] Figure 4 is a hydraulic circuit diagram of an electro-hydraulic brake according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0012] In view of the above, the present disclosure provides an electro-hydraulic brake in which a main brake unit and a hydraulic controller are formed in one housing, thereby improving the cost competitiveness of the electro-hydraulic brake and ensuring required performance.

[0013] The problems to be solved by the present disclosure are not limited to the above problems, and those skilled in the art will clearly understand other problems not mentioned from the following description.

[0014] In the following, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, although elements are shown in different drawings, the same reference numerals preferably denote the same elements. Further, in the following description of some embodiments, for the purpose of clarity and conciseness, detailed descriptions of related known components and functions will be omitted when they are considered to obscure the subject matter of the present disclosure.

[0015] In addition, alphanumeric codes in numbered components, such as first, second, i), ii), (a), (b), etc. are for the sole purpose of differentiating one component from another, and do not imply or suggest the essence, order, or sequence of the components. Throughout the specification, when a part "comprises" or "includes" a component, it means that it also includes other components, excluding other components only when there is a specific description to the contrary. Terms such as "unit", "module", etc. refer to one or more units for processing at least one function or operation, which can be implemented by hardware, software, or a combination thereof.

[0016] Figure 1 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0017] Referring to Figure 1 , the electro-hydraulic brake 1 according to an embodiment of the present disclosure may include all or some of a reservoir 110, a main brake unit 100, a hydraulic controller 200, a first controller 10, and a second controller 20.

[0018] The main brake unit 100 may include a main brake motor 122, a master cylinder 120 configured to change the pressure of the brake oil in cooperation with the main brake motor 122, and a reservoir 110 for storing the brake oil. In an embodiment of the present disclosure, the main brake motor 122 may be an electric booster.

[0019] The hydraulic controller 200 may include an auxiliary brake motor 230, a plurality of pumps 231 and 232 configured to change the pressure of the brake oil in cooperation with the auxiliary brake motor 230, and a hydraulic block 210 configured to selectively transmit the pressure of the brake oil formed in the master cylinder 120 or the pumps 231 and 232 to all or some of a plurality of wheel brakes w1, w2, w3, and w4.

[0020] The hydraulic block 210 may include one or more main flow paths 211 and 212 configured to transmit the hydraulic pressure of the brake oil from the master cylinder 120 to a plurality of wheel brakes w1, w2, w3, and w4, one or more auxiliary flow paths 221 and 222 directly connecting the reservoir 110 to the pumps 231 and 232 to transmit the brake oil, and one or more valves.

[0021] The hydraulic controller 200 may include one or more auxiliary flow path ports 220 configured such that the auxiliary flow paths 221 and 222 are connected to the reservoir 110 without passing through the master cylinder 120. The auxiliary flow path ports 220 may be in the same housing as the master cylinder 120. Using the auxiliary flow path ports 220, the brake fluid may be transmitted to the plurality of wheel brakes w1, w2, w3, and w4 via the hydraulic block 210 and the connection block 215 without passing through the master cylinder 120. The connection block 215 will be described in detail below. In other words, according to an embodiment of the present disclosure, using the auxiliary flow path ports 220 and the auxiliary flow paths 221 and 222, the brake fluid may be transmitted from the reservoir 110 to the plurality of wheel brakes w1, w2, w3, and w4 in parallel with the pressure formed in the master cylinder 120 of the brake fluid.

[0022] One end of each of the auxiliary flow paths 221 and 222 is connected to the reservoir 110 using the auxiliary flow path ports 220 located in the housing of the master cylinder 120. The other end of each of the auxiliary flow paths 221 and 222 is connected to the hydraulic block 210. As a result, the auxiliary flow paths 221 and 222 directly connect the reservoir 110 and the pumps 231 and 232 housed in the hydraulic block 210 to guide the brake fluid from the reservoir 110 to the pumps 231 and 232.

[0023] The hydraulic block 210 may have a rectangular parallelepiped shape. The hydraulic block 210 may be provided with a first side surface 210a, a second side surface 210b, and a third side surface 210c. A plurality of ports connected to the flow path are located in the first side surface, the auxiliary brake motor 230 is attached to the second side surface, and the second controller 20 is attached to the third side surface. The second side surface 210b extends from the first side surface 210a. The third side surface 210c is located on the opposite side of the second side surface 210b and extends from the first side surface 210a.

[0024] In the electro-hydraulic brake 1 according to an embodiment of the present disclosure, one or more side surfaces of the master cylinder 120 and the hydraulic block 210 may be coupled to each other. The master cylinder 120 may include one or more connection members 120a that hydraulically couple the master cylinder 120 and the hydraulic block 210. That is, by coupling the master cylinder 120 and the hydraulic block 210, the master brake unit 100 and the hydraulic controller 200 may be directly physically coupled to each other without being coupled via a brake pipe. In another embodiment, the hydraulic circuit and the components of the master brake unit 100 and the hydraulic controller 200 may be housed in one housing to form one box. Since the electro-hydraulic brake is configured in the shape of one box, the number of valves may be reduced, and the accumulator and the check valve may be eliminated, thereby saving costs. In addition, the brake pipe layout can be simplified.

[0025] Reference Figure 1 , in an embodiment of the present disclosure, the master cylinder 120 and the hydraulic block 210 may be directly coupled to each other using a connection member 120a. The master cylinder 120 may be coupled to the second side surface 210b of the hydraulic block 210. The coupling relationship between the master cylinder 120 and the hydraulic block 210 may be changed in various ways for design convenience and need not be limited to Figure 1 the layout. When the master cylinder 120 and the hydraulic block 210 are coupled, the longitudinal central axis a (see Figure 1 ) of the master cylinder 120 and the longitudinal central axis b (see Figure 1 ) of the auxiliary brake motor 230 are arranged perpendicular to each other.

[0026] The first controller 10 is configured to control the main brake motor 122 according to a braking input. The second controller 20 is configured to control the auxiliary brake motor 230 according to a braking input. The first controller 10 and the second controller 20 may be configured to send an electrical signal to an electronic parking brake (EPB). However, the present disclosure is not limited to such a configuration. For example, the first controller 10 may be configured to control the main brake motor 122 and the auxiliary brake motor 230 according to a braking input. Here, the braking input may be understood as an electronic signal, such as a pedal sensing signal (PSS), which is generated based on a braking signal provided from a user's pedal input or a separate autonomous driving device. Each of the first controller 10 and the second controller 20 may be an electronic control unit (ECU). The second controller 20 may include a connector 20a. When the master cylinder 120 and the hydraulic block 210 are coupled to each other, the longitudinal central axis b (see Figure 1 ) of the auxiliary brake motor 230 and the direction c (see Figure 1 ) of the connector 20a of the second controller 20 are arranged parallel to each other.

[0027] Figure 2 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0028] Figure 3 is a perspective view of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0029] Reference Figure 2 and Figure 3 , an electro-hydraulic brake 1 according to an embodiment of the present disclosure may include a connection block 215. The connection block 215 is located between the master cylinder 120 and the hydraulic block 210 to indirectly couple the master cylinder 120 and the hydraulic block 210. The connection block 215 may have one or more flow paths for guiding brake oil and one or more valves in the one or more flow paths. The connection block 215 is used to hydraulically connect the master cylinder 120 and the hydraulic block 210. The connection block 215 may have a rectangular parallelepiped shape.

[0030] Reference Figure 2 and Figure 3 , one side of the connection block 215 is coupled to the master cylinder 120. Among the sides other than the side coupled to the master cylinder 120, one or more sides may be coupled to the hydraulic block 210. The connection block 215 may be coupled to the first side 210a or the second side 210b of the hydraulic block 210. The coupling relationship among the master cylinder 120, the connection block 215, and the hydraulic block 210 may be changed in various ways for design convenience and need not be limited to Figure 2 or Figure 3 the layout.

[0031] Even when forming a layout using the master cylinder 120, the connection block 215, and the hydraulic block 210, the longitudinal central axis b of the master cylinder 120 (see Figure 2 and Figure 3 ) and the longitudinal central axis b of the auxiliary brake motor 230 (see Figure 2 and Figure 3 ) are also arranged perpendicular to each other. In addition, the longitudinal central axis b of the auxiliary brake motor 230 (see Figure 2 and Figure 3 ) and the direction c of the connector 20a of the second controller 20 (see Figure 2 and Figure 3 ) are arranged parallel to each other.

[0032] Figure 4 is a hydraulic circuit diagram of an electro-hydraulic brake according to an embodiment of the present disclosure.

[0033] Reference Figure 4 , the electro-hydraulic brake 1 according to an embodiment of the present disclosure may include all or some of a plurality of wheel brakes w1, w2, w3, and w4 that supply braking force to the wheels of a vehicle, a main brake unit 100, a hydraulic controller 200, a first controller 10, and a second controller 20.

[0034] The main brake unit 100 may include a main brake motor 122, a master cylinder 120 configured to change the pressure of the brake oil in cooperation with the main brake motor 122, a reservoir 110 that stores the brake oil, and a plurality of supply flow paths 131 and 132 that supply the brake oil from the reservoir 110 to the master cylinder 120. In an embodiment of the present disclosure, the main brake motor 122 may be an electric booster.

[0035] The hydraulic controller 200 may include an auxiliary brake motor 230, a plurality of pumps 231 and 232 configured to change the pressure of the brake oil in cooperation with the auxiliary brake motor 230, one or more main flow paths 211 and 212 configured to transfer the hydraulic pressure of the brake oil from the master cylinder 120 to the plurality of wheel brakes w1, w2, w3, and w4, one or more auxiliary flow paths 221 and 222 directly connecting the reservoir 110 to the pumps 231 and 232 to transfer the brake oil, and one or more valves configured to selectively transfer the pressure of the brake oil formed in the master cylinder 120 or the pumps 231 and 232 to the plurality of wheel brakes w1, w2, w3, and w4.

[0036] The hydraulic controller 200 is in fluid communication with the reservoir 110, the master cylinder 120, the pumps 231 and 232, and the plurality of wheel brakes w1, w2, w3, and w4 and responds to signals from the first controller or the second controller. The hydraulic controller 200 is configured to change the internal flow path, i.e., the path on which the hydraulic pressure acts or the path along which the brake oil flows between the reservoir 110, the master cylinder 120, the pumps 231 and 232, and the plurality of wheel brakes w1, w2, w3, and w4.

[0037] The plurality of wheel brakes w1, w2, w3, and w4 are configured to apply a braking force to the wheels of the vehicle using hydraulic pressure. Each of the wheel brakes w1, w2, w3, and w4 may be a caliper brake. The plurality of wheel brakes w1, w2, w3, and w4 may be selectively in fluid communication with at least one of the reservoir 110, the master cylinder 120, and the pumps 231 and 232 using the hydraulic controller 200. For example, the hydraulic pressure generated in the master cylinder 120 or the pumps 231 and 232 may be applied to the plurality of wheel brakes w1, w2, w3, and w4 using the hydraulic controller 200. The plurality of wheel brakes w1, w2, w3, and w4 may apply a braking force corresponding to the hydraulic pressure to the wheels of the vehicle.

[0038] The master cylinder 120 is configured to change the pressure of the brake oil in response to a signal from the first controller 10. The master cylinder 120 has a hollow structure. The master cylinder 120 includes a piston disposed therein and two hydraulic chambers separated by the piston. The piston is configured to move to one side as the main brake motor 122 rotates, i.e., reciprocate and translate between the hydraulic chambers. When the main brake motor moves clockwise or counterclockwise in response to a signal from the first controller 10, the piston may move to one side or the other to press the brake oil filled in the two hydraulic chambers.

[0039] Pumps 231 and 232 are configured to change the pressure of the brake fluid in response to a signal from the second controller 20. Pumps 231 and 232 may have the structure of an oil pump. For example, the pump may be configured to pump the brake fluid in coordination with the rotation of the auxiliary brake motor 230 as the auxiliary brake motor 230 operates in response to a signal from the second controller 20. The flow path of the brake fluid through pumps 231 and 232 may lead to the plurality of wheel brakes w1, w2, w3, and w4 by way of the hydraulic controller 200.

[0040] The hydraulic controller 200 of the electro-hydraulic brake 1 according to an embodiment of the present disclosure includes all or some of a plurality of traction control valves 241 and 242, a plurality of inlet valves 251 to 254, and a plurality of outlet valves 261 to 264 related to the operation of the master cylinder 120 and pumps 231 and 232. The traction control valves 241 and 242 and the inlet valves 251 to 254 may be normally open solenoid valves, while the outlet valves 261 to 264 may be normally closed solenoid valves.

[0041] The hydraulic controller 200 includes four pairs of inlet valves 251 to 254 and outlet valves 261 to 264 provided on the brake flow path, through which the brake fluid is directly supplied to or discharged from each of the wheel brakes w1, w2, w3, and w4. In addition, the hydraulic controller 200 includes a first traction control valve 241 and a second traction control valve 242 for distributing the hydraulic pressure generated from the master cylinder 120 to each brake flow path. The traction control valves 241 and 242 are configured to open or close the main flow paths 211 and 212 between the master cylinder 120 and the plurality of wheel brakes w1, w2, w3, and w4, and to regulate the hydraulic pressure transmitted to the plurality of wheel brakes w1, w2, w3, and w4.

[0042] The plurality of valves are configured to independently control the braking forces of the plurality of wheel brakes w1, w2, w3, and w4, respectively. For example, the valves are configured to implement the functions of an ABS (antilock braking system), a TCS (traction control system), and an ESC (electronic stability control).

[0043] The hydraulic controller 200 of the electro-hydraulic brake 1 according to an embodiment of the present disclosure includes a plurality of auxiliary flow paths 221 and 222 that directly guide the brake fluid supplied from the reservoir 110 to pumps 231 and 232 without passing through the master cylinder 120. The hydraulic controller 200 may include a plurality of return flow paths 271 and 272 that directly guide the brake fluid to the reservoir 110 without passing through the master cylinder 120 when the electro-hydraulic brake 1 is depressurized.

[0044] When the master cylinder 120 or the first controller 10 fails, the auxiliary brake motors 230 of the pumps 231 and 232 operate in response to a signal from the second controller 20. The pumps 231 and 232 that cooperate with the auxiliary brake motor 230 transfer brake oil from the reservoir 110 to the plurality of wheel brakes w1, w2, w3, and w4 using the auxiliary flow paths 221 and 222. The brake oil is transferred to the plurality of wheel brakes w1, w2, w3, and w4 so that effective auxiliary braking can be achieved through electronic control in the case of auxiliary braking.

[0045] In addition, when the master cylinder 120 or the first controller 10 fails with the brake pedal released, the outlet valves 261 to 264 are controlled in response to a signal from the second controller 20, and the brake oil is transferred to the reservoir 110 using the return flow paths 271 and 272 without passing through the master cylinder 120.

[0046] Considering the possibility that the devices performing the functions of the electro-hydraulic brake may fail, the possibility of problems occurring due to the failure of the electro-hydraulic brake can be eliminated by further including additional devices having similar functions. In other words, a braking device capable of ensuring redundancy can be achieved. For example, even when a failure of the main braking unit occurs in a situation where the driver's driving is excluded or the driving attention is reduced, such as in the case of intelligent cruise control or autonomous driving, auxiliary braking force can be appropriately provided.

[0047] The electro-hydraulic brake according to an embodiment of the present disclosure may further include electronic parking brakes (EPBs) 31 and 32 mounted on one or more wheels. In the embodiment of the present disclosure, the electronic parking brakes 31 and 32 are illustrated as being integrally mounted on two wheel brakes w1 and w2 of the rear wheels. The two electronic parking brakes 31 and 32 may be configured to be controlled by electrical signals from the first controller 10 and the second controller 20.

[0048] For example, when the main braking unit 100 fails, the hydraulic controller 200 and the EPBs 31 and 32 perform braking. When the hydraulic controller 200 fails, the main braking unit 100 and the EPBs 31 and 32 perform braking. When the EPBs 31 and 32 fail, the main braking unit 100, the hydraulic controller 200, and the EPBs 31 and 32 may be hydraulically and electrically configured such that the main braking unit 100 and the hydraulic controller 200 can perform redundant functions.

[0049] According to an embodiment, the advantage of the electro-hydraulic brake is that the braking system is formed as a single housing, thereby simplifying the brake line layout, reducing the number of components, and thus reducing costs.

[0050] Although exemplary embodiments of the present disclosure have been described for illustrative purposes, those skilled in the art will understand that various modifications, additions, and substitutions are possible without departing from the spirit and scope of the claimed invention. Therefore, the exemplary embodiments of the present disclosure have been described for the sake of brevity and clarity. The scope of the technical idea of this embodiment is not limited by the drawings. Therefore, those of ordinary skill in the art will understand that the scope of the claimed invention is not limited by the embodiments explicitly described above, but is limited by the claims and their equivalents.

[0051] Cross - reference to related applications

[0052] This application is based on and claims priority to Korean Patent Application No. 10 - 2021 - 0091227, filed on July 12, 2021, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. An electro-hydraulic brake, the electro-hydraulic brake comprising: a plurality of wheel brakes configured to supply braking force to wheels of a vehicle; a reservoir storing brake fluid; a master cylinder connected to the reservoir and cooperating with a main brake motor to generate pressure of the brake fluid; a first controller configured to control the main brake motor according to a braking input; a hydraulic controller including a pump and a hydraulic block, the pump configured to form the pressure of the brake fluid in cooperation with an auxiliary brake motor, the hydraulic block configured to selectively transfer the pressure of the brake fluid formed in the master cylinder or the pump to the plurality of wheel brakes; and a second controller configured to control the auxiliary brake motor when a failure occurs in the master cylinder or the first controller, wherein the hydraulic controller is provided with at least one auxiliary flow path to directly transfer the brake fluid from the reservoir to the pump through the at least one auxiliary flow path, and wherein the hydraulic block has a first side and a second side, a plurality of ports connected to the auxiliary flow path are located in the first side, the auxiliary brake motor is attached to the second side, and at least one side of the hydraulic block is coupled to the master cylinder, wherein the master cylinder is fixedly coupled to the first side or the second side of the hydraulic block.

2. The electro-hydraulic brake according to claim 1, wherein, A longitudinal central axis of the master cylinder and a longitudinal central axis of the auxiliary brake motor are arranged perpendicular to each other.

3. The electro-hydraulic brake according to claim 1, wherein, The second controller is attached to a third side located on a side opposite to the second side of the hydraulic block.

4. The electro-hydraulic brake according to claim 1, wherein, The hydraulic controller further includes a connector, and wherein the connector is vertically coupled to the second controller, and a direction of the connector is parallel to a longitudinal central axis of the auxiliary brake motor.

5. The electro-hydraulic brake according to claim 1, wherein, The master cylinder further includes: at least one connection member that hydraulically connects the master cylinder to a side of the hydraulic block.

6. The electro-hydraulic brake according to claim 1, wherein, The auxiliary flow path further includes at least one auxiliary flow path port configured to be connected to the reservoir without passing through the master cylinder, and wherein the auxiliary flow path port is located in the same housing as the master cylinder and is configured to be parallel to the master cylinder.

7. The electro-hydraulic brake according to claim 1, wherein, The hydraulic block includes a plurality of flow paths guiding the brake fluid and a plurality of valves in the plurality of flow paths.

8. The electro-hydraulic brake according to claim 1, the electro-hydraulic brake further comprising: a connection block located between the master cylinder and the hydraulic block and configured to indirectly couple the master cylinder and the hydraulic block.

9. The electro-hydraulic brake according to claim 8, wherein, The connection block hydraulically connects the master cylinder and the hydraulic block.

10. The electro-hydraulic brake according to claim 8, wherein, The connection block includes a plurality of flow paths guiding the brake fluid and a plurality of valves in the plurality of flow paths.

11. The electro-hydraulic brake according to claim 8, wherein, The connection block is fixedly coupled to the first side or the second side of the hydraulic block.

12. The electro-hydraulic brake according to claim 1, the electro-hydraulic brake further comprising: Electronic parking brake EPB, wherein the first controller is configured to send an electrical signal to the electronic parking brake EPB when a failure occurs in the master cylinder or the first controller.

13. The electro-hydraulic brake according to claim 1, wherein the electro-hydraulic brake further comprises: Electronic parking brake EPB, wherein the second controller is configured to send an electrical signal to the electronic parking brake EPB when a failure occurs in the hydraulic controller or the second controller.

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