Electronic brake system

Abstract

The present application provides an electronic brake system. According to the electronic brake system of one aspect of the present application, comprising: a pedal unit connected with a brake pedal and operated by the pedal force of a driver; and a brake operation unit generating pressure of a pressurized medium for braking a vehicle according to a signal output corresponding to the displacement of the brake pedal. Wherein, the pedal unit comprises a pedal displacement actuator which displaces the brake pedal from a first position to a second position when entering an unmanned mode which does not require brake operation of the driver; the brake operation unit comprises a first control part which controls the generation of the pressure; when entering the unmanned mode, the first control part can control the pedal displacement actuator to displace the brake pedal from the first position to the second position.

Description

Technical Field

[0001] This invention relates to electronic braking systems, and more specifically, to electronic braking systems that generate braking force using signals corresponding to changes in the position of the brake pedal. Background Technology

[0002] Research and development on autonomous driving, where vehicles can operate automatically without driver intervention in steering, acceleration, and braking, is actively underway. Consequently, the level of autonomous driving applicable to vehicles is increasing, and the need for driver operation is gradually decreasing.

[0003] As mentioned above, with the development of autonomous driving technology, there is a growing demand for repositioning mechanisms such as the steering wheel and brake pedal, which do not require driver operation in autonomous driving mode, thus increasing the utilization of space around the driver's seat. For example, if the brake pedal is moved to the front of the vehicle in autonomous driving mode, the driver can make extensive use of the legroom in the driver's seat.

[0004] On the other hand, existing braking systems have a structure that supplies the hydraulic pressure required by the brake wheel cylinders via a mechanically connected booster when the driver depresses the brake pedal. However, recently, in order to effectively realize various braking functions, an electronic braking system is becoming widely popular. When the driver depresses the brake pedal, a pedal position sensor or the like converts the driver's braking intention into an electrical signal, and the hydraulic supply device supplies the hydraulic pressure required for braking to the brake wheel cylinders according to the electrical signal.

[0005] In this situation, there is a need to develop a technology that can effectively and stably achieve the displacement of the brake pedal in the autonomous driving mode as described above in the electronic braking system. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] The present invention is intended to solve the problems described above. The purpose of the present invention is to provide an electronic braking system that repositions the brake pedal to improve the utilization of legroom in the driver's seat in an autonomous driving mode where brake pedal operation is not required.

[0008] Another object of the present invention is to provide an electronic braking system that reliably repositions the brake pedal to a position operable by the driver when the driver-controlled mode ends and the driver needs to perform braking operations.

[0009] The subject matter of this invention is not limited to those mentioned above, but may be clearly understood by those skilled in the art from the following description.

[0010] (II) Technical Solution

[0011] According to one aspect of the present invention, an electronic braking system is provided, comprising: a pedal unit connected to a brake pedal and operated by a driver's pedal force; and a brake operation unit that generates pressure of a pressurized medium for braking a vehicle based on a signal output corresponding to a change in the position of the brake pedal. The pedal unit includes a pedal displacement actuator that, when entering an autonomous driving mode where driver braking is not required, displaces the brake pedal from a first position to a second position; the brake operation unit includes a first control unit that controls the generation of the pressure; and when entering the autonomous driving mode, the first control unit controls the pedal displacement actuator to displace the brake pedal from the first position to the second position.

[0012] At this time, the second position can be the same as the position of the brake pedal when the brake pedal is pressed with a predetermined force.

[0013] In addition, the second position is a position where the brake pedal can be linearly displaced forward of the vehicle.

[0014] Alternatively, the second position can be the position where the brake pedal is close to the boundary between the driver's seat and the front engine compartment of the vehicle, i.e., the position on the firewall side.

[0015] In addition, when the driver needs to brake to end the autonomous driving mode, the first control unit can control the pedal displacement actuator to move the brake pedal from the second position to the first position.

[0016] In addition, the first control unit sends control signals for the pedal position actuator to the pedal position actuator via the vehicle's CAN (Controller Area Network).

[0017] In addition, the first control unit is directly connected to the pedal position actuator. If the transmission of the control signal for the pedal position actuator via the vehicle's CAN fails, the first control unit can directly transmit the control signal to the pedal position actuator.

[0018] In addition, the first control unit can be directly connected to the pedal position actuator via wiring that can transmit the control signal for the pedal position actuator.

[0019] In addition, the braking operation unit also includes a pressure pump, which generates the pressure of the pressurizing medium according to the signal, and the first control unit can control at least a portion of the power of the pressure pump.

[0020] In addition, the pedal unit and the braking operation unit can be physically separated from each other.

[0021] In addition, the braking operation unit also includes a second control unit, which controls the generation of pressure together with the first control unit or, in the event of a failure of the first control unit, takes over the control of the pressure generation. When entering the autonomous driving mode, if the first control unit fails to control the pedal displacement actuator, the second control unit can control the pedal displacement actuator to move the brake pedal from the first position to the second position.

[0022] In addition, the first control unit and the second control unit can be connected to independent power supplies.

[0023] In addition, the first control unit and the second control unit are configured in a single control module package, and each can be configured with an independent PCB (printed circuit board).

[0024] Additionally, the pedal unit includes a pedal simulator, which may include: a cylinder body having a single chamber on its inner side; an elastic member disposed inside the chamber; and a piston that presses the elastic member by applying a force to the brake pedal.

[0025] Additionally, a pressurizing medium is filled in the chamber, and the pressurizing medium filled in the chamber in the reversing mode of the braking operation unit can be supplied to the braking operation unit.

[0026] (III) Beneficial Effects

[0027] The electronic braking system of the present invention can effectively change the position of the brake pedal through a pedal displacement actuator in an unmanned driving mode where the driver does not need to operate the brake pedal, thereby improving the space utilization of the legroom in the driver's seat in the unmanned driving mode.

[0028] The electronic braking system of the present invention provides high reliability during brake pedal displacement by ensuring control redundancy of the pedal displacement actuator.

[0029] The effects of the present invention are not limited to those described above, but should be understood to include all effects that can be inferred from the detailed description of the invention or the structure of the invention as set forth in the claims. Attached Figure Description

[0030] Figure 1 This is a structural diagram of the electronic braking system according to the first embodiment of the present invention.

[0031] Figure 2 This is a diagram showing the brake pedal changing from a first position to a second position in the electronic braking system of the first embodiment of the present invention.

[0032] Figure 3 This is a diagram illustrating the control-related structures and the flow of signals and power in the electronic braking system according to a first embodiment of the present invention.

[0033] Figure 4 This is a structural diagram of the electronic braking system according to the second embodiment of the present invention.

[0034] Figure 5 This is a diagram showing the brake pedal changing from a first position to a second position in an electronic braking system according to a second embodiment of the present invention. Detailed Implementation

[0035] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings to enable those skilled in the art to readily implement the invention. The present invention can be implemented in various different forms and is not limited to the embodiments described herein. For the sake of clarity, parts unrelated to the description are omitted.

[0036] The embodiments described in this specification and the structures shown in the accompanying drawings are preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, at the time of application of the present invention, there may be various equivalents and modifications of this structure.

[0037] In this specification, the terms "including" or "having" should be understood as specifying the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, without precluding the possibility of the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Furthermore, "connected" to another component means, unless otherwise specified, that it includes not only direct connections but also indirect connections.

[0038] Figure 1 This is a structural diagram of the electronic braking system according to the first embodiment of the present invention.

[0039] Reference Figure 1 The electronic braking system of the first embodiment of the present invention may include: a pedal unit 1000A connected to the brake pedal 10 and operated by the driver's pedal force; and a brake operation unit 1000B that generates pressure of a pressurized medium for braking the vehicle based on a signal output corresponding to the displacement of the brake pedal 10. At this time, the displacement of the brake pedal 10 can be detected by a pedal displacement sensor 11, and the signal can be an electrical signal output by the pedal displacement sensor 11.

[0040] In the first embodiment of the present invention, the pedal unit 1000A and the brake operation unit 1000B can be physically separated from each other. By physically separating the pedal unit 1000A and the brake operation unit 1000B, the flexibility in setting up the electronic braking system can be improved. For example, the pedal unit 1000A can be configured adjacent to the driver's seat, and the brake operation unit 1000B can be configured in other spare space inside the vehicle, thereby improving the space utilization of the vehicle and the ease of setting up the electronic braking system.

[0041] The pedal unit 1000A includes a pedal displacement actuator 120, which displaces the brake pedal 10 from a first position to a second position when entering an autonomous driving mode where driver braking is not required. The pedal displacement actuator 120 can directly change the position of the brake pedal 10 or change the position of any structure connected to the brake pedal 10, thereby altering the position of the brake pedal 10. For example, the first position is where the driver can operate the brake pedal 10, while the second position can be a position where the brake pedal 10 is moved away from the driver's seat to improve the utilization of legroom. In autonomous driving mode, the brake pedal 10 is positioned in the second position, thereby expanding the space available for the driver's leg movement and improving the vehicle's space utilization.

[0042] The pedal position actuator 120 can be mounted on the connection tool 12 side of the pedal simulator 1200 described later. However, the mounting position of the pedal position actuator 120 is not limited, and it can also be mounted on any other structural side connected to the brake pedal 10. On the other hand, the pedal position actuator 120 may include a drive motor.

[0043] Figure 2 This is a diagram illustrating the change of the brake pedal from a first position to a second position in the electronic braking system of the first embodiment of the present invention. (Refer to...) Figure 2 In the first embodiment of the present invention, the second position may be the same as the position of the brake pedal 10 when it is depressed with a predetermined force. Of course, the second position should not be limited by the first embodiment of the present invention. As another example, the second position may be a position where the brake pedal 10 is linearly displaced forward of the vehicle. Alternatively, the second position may also be a position where the brake pedal 10 is close to the boundary between the driver's seat and the engine compartment at the front of the vehicle, i.e., on the firewall side.

[0044] On the other hand, when the autonomous driving mode ends and the driver needs to brake, the pedal displacement actuator 120 moves the brake pedal 10 from the second position to the first position. Accordingly, the driver can operate the brake pedal 10.

[0045] Additionally, the pedal unit 1000A also includes a pedal simulator 1200, which generates a reaction force to the driver's pedal force to provide the driver with pedal feel. When the driver applies pedal force to the brake pedal 10 for braking, the pedal simulator 1200 provides the driver with a reaction force to that pedal force, thereby providing a stable pedal feel.

[0046] The pedal simulator 1200 may include: a cylinder body 1210; a single chamber 1220 formed inside the cylinder body 1210; an elastic member 1230 disposed inside the chamber 1220; and a piston 1240 that presses the elastic member 1230 by a force applied to the brake pedal 10. The piston 1240 is connected to the brake pedal 10 via a connecting tool 12 and is reciprocally accommodated in the chamber 1220. For example, the connecting tool 12 may be an input rod. The piston 1240 presses the elastic member 1230 by a force applied to the brake pedal 10. The elastic member 1230 is compressed as the piston 1240 displaces by the force applied, providing pedal feel.

[0047] In a first embodiment of the present invention, an elastic member 1230 is disposed in the chamber 1220 of the pedal simulator 1200, and the chamber 1220 is not filled with a pressurizing medium. This pedal simulator 1200 can be defined as a dry type.

[0048] The brake operation unit 1000B generates pressure for the pressurized medium used to brake the vehicle based on a signal output corresponding to the displacement of the brake pedal 10. In a first embodiment of the present invention, the brake operation unit 1000B may include a first control unit 130 and a second control unit 140. The first control unit 130 controls the generation of pressure of the pressurized medium. Furthermore, the second control unit 140 controls the generation of pressure of the pressurized medium together with the first control unit 130, or replaces the first control unit 130 in controlling the generation of pressure of the pressurized medium when the first control unit 130 fails.

[0049] The first control unit 130 controls the pressure generation of the pressurized medium and simultaneously controls the pedal displacement actuator 120. More specifically, when entering the autonomous driving mode, the first control unit 130 controls the pedal displacement actuator 120 to move the brake pedal 10 from a first position to a second position. Additionally, when the autonomous driving mode ends and driver braking is required, the first control unit 130 can control the pedal displacement actuator 120 to move the brake pedal 10 from the second position to the first position.

[0050] The second control unit 140 can control the pedal displacement actuator 120 to move the brake pedal 10 from the first position to the second position if the first control unit 130 fails to control the pedal displacement actuator 120 when entering the autonomous driving mode. Furthermore, even when the autonomous driving mode ends and driver braking is required, if the brake pedal 10 cannot move from the second position to the first position due to the first control unit 130's failure to control the pedal displacement actuator 120, the second control unit 140 can control the pedal displacement actuator 120 to move the brake pedal 10 from the second position to the first position. Therefore, the displacement of the brake pedal 10 is reliably achieved when entering and ending the autonomous driving mode.

[0051] The first control unit 130 and the second control unit 140 can send control signals for the pedal position actuator 120 to the vehicle's CAN(C) network. That is, the first control unit 130 and the second control unit 140 can be indirectly connected to the pedal position actuator 120 via the vehicle's CAN(C) network.

[0052] Furthermore, the first control unit 130 and the second control unit 140 can be directly connected to the pedal position actuator 120. That is, in the event of a failure to transmit the control signal via CAN(C), either the first control unit 130 or the second control unit 140 can directly transmit the control signal to the pedal position actuator 120. More specifically, the first control unit 130 and the second control unit 140 can be directly connected to the pedal position actuator 120 via wiring that allows the transmission of control signals. (See also...) Figure 1 The first control unit 130 can be directly connected to the pedal position actuator 120 via the first line W1, and the second control unit 140 can be directly connected to the pedal position actuator 120 via the second line W2.

[0053] The braking operation unit 1000B may further include: a reservoir 1100 for storing pressurized medium; a pressure pump 1300 for receiving an electrical signal corresponding to the driver's braking intention from a pedal displacement sensor 11 that detects the displacement of the brake pedal 10, thereby generating pressure of the pressurized medium through mechanical operation; a pressure regulating unit 1400 for regulating the pressure of the pressurized medium discharged from or returned to the pressure pump 1300; first and second hydraulic circuits 1510 and 1520, having wheel cylinders 21, 22, 23, and 24, which transmit hydraulic pressure of the pressurized medium to perform braking of each wheel; and a pressure transfer unit 1700 disposed between the pressure pump 1300 and the reservoir 1100 to control the flow of the pressurized medium.

[0054] The reservoir 1100 can contain and store pressurized medium inside. The reservoir 1100 is connected to multiple components such as the pressure pump 1300, the first and second hydraulic circuits 1510 and 1520, and the pressure transfer unit 1700 to supply or receive pressurized medium.

[0055] The pressure pump 1300 generates pressure of the pressurized medium according to the signal. For example, the first control unit 130 controls a portion of the power of the pressure pump 1300, while the second control unit 140 can control the remaining power of the pressure pump 1300. In the first embodiment of the invention, the pressure pump 1300 can be driven by a motor 1380, which can be a dual-winding motor. In this case, the first control unit 130 supplies power to one winding of the dual-winding motor, while the second control unit 140 can supply power to the remaining winding. On the other hand, in the event of a failure of either the first control unit 130 or the second control unit 140, the remaining winding can generate additional power to control the pressure pump 1300.

[0056] The pressure pump 1300 may further include: a cylinder 1310 for containing the pressurized medium; a hydraulic piston 1320 housed within the cylinder 1310; and sealing components 1350a and 1350b disposed between the hydraulic piston 1320 and the cylinder 1310 to seal the pressure chambers 1330 and 1340. At this time, the motor 1380 rotates via an electrical signal from the pedal position sensor 11, and the driving force of the motor 1380 is transmitted to the hydraulic piston 1320 via the drive shaft 1390.

[0057] Pressure chambers 1330 and 1340 may include: a first pressure chamber 1330 located on one side of the hydraulic piston 1320; and a second pressure chamber 1340 located on the other side of the hydraulic piston 1320. Additionally, sealing components 1350a and 1350b include: a piston sealing component 1350a disposed between the hydraulic piston 1320 and the cylinder 1310 to seal the space between the first pressure chamber 1330 and the second pressure chamber 1340; and a drive shaft sealing component 1350b disposed between the drive shaft 1390 and the cylinder 1310 to seal the opening between the second pressure chamber 1340 and the cylinder 1310.

[0058] When the motor 1380 rotates in one direction, the drive shaft 1390 moves the hydraulic piston 1320 to one side, thereby generating pressure in the first pressure chamber 1330. Conversely, when the motor 1380 rotates in another direction, the drive shaft 1390 moves the hydraulic piston 1320 to the other side, thereby generating pressure in the second pressure chamber 1340.

[0059] The pressure regulating unit 1400 can regulate the flow of pressurized medium from the pressure pump 1300 to the cylinders 21, 22, 23, and 24, or from the cylinders 21, 22, 23, and 24 back to the pressure pump 1300. The pressure regulating unit 1400 may include multiple flow paths and valves to flexibly regulate the flow or pressure of the pressurized medium. The valves included in the pressure regulating unit 1400 can be controlled by either the first control unit 130 or the second control unit 140. Specifically, the first control unit 130 performs control first, and if the first control unit 130 fails, the second control unit 140 can perform control.

[0060] The first hydraulic circuit 1510 controls the flow of pressurized medium supplied from the pressure regulating unit 1400 to the first cylinder 21 and the second cylinder 22. The second hydraulic circuit 1520 controls the flow of pressurized medium supplied to the third cylinder 23 and the fourth cylinder 24. The first hydraulic circuit 1510 and the second hydraulic circuit 1520 can be controlled by either the first control unit 130 or the second control unit 140. Specifically, the first control unit 130 and the second control unit 140 can control one or more valves configured in the first hydraulic circuit 1510 and the second hydraulic circuit 1520. In the first embodiment of the present invention, the first control unit 130 first controls the first hydraulic circuit 1510 and the second hydraulic circuit 1520; if the first control unit 130 fails to control them, the second control unit 140 can control the first hydraulic circuit 1510 and the second hydraulic circuit 1520.

[0061] The first hydraulic circuit 1510 and the second hydraulic circuit 1520 may have first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b to control the flow and pressure of the pressurized medium delivered to the first to fourth wheel cylinders 21, 22, 23, and 24, respectively. Additionally, the first and second hydraulic circuits 1510 and 1520 may include first to fourth check valves 1513a, 1513b, 1523a, and 1523b, which are connected in parallel with the first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b. The first to fourth check valves 1513a, 1513b, 1523a, and 1523b are configured as bypasses, allowing only the flow of the pressurized medium from each wheel cylinder toward the pressure pump 1300.

[0062] Additionally, the first and second hydraulic circuits 1510 and 1520 may have first to fourth outlet valves 1512a, 1512b, 1522a, and 1522b, which control the flow of pressurized medium discharged from the first to fourth wheel cylinders 21, 22, 23, and 24 to the reservoir 1100 to improve performance when the wheel cylinders are released from braking. The discharge sides of the first and second outlet valves 1512a and 1512b are connected to the reservoir 1100 via a first discharge flow path 1610. Furthermore, the discharge sides of the third and fourth outlet valves 1522a and 1522b are connected to the reservoir 1100 via a second discharge flow path 1620.

[0063] The pressure transfer unit 1700 regulates the flow of the pressurizing medium between the pressure pump 1300 and the reservoir 1100. The pressure transfer unit 1700 may include multiple flow paths and valves. The valves included in the pressure transfer unit 1700 may be controlled by either the first control unit 130 or the second control unit 140. Specifically, the first control unit 130 performs control first, and if the first control unit 130 fails, the second control unit 140 may perform control.

[0064] When the electronic braking system of the first embodiment of the present invention brakes, the braking operation unit operates as follows.

[0065] As the motor 1380 of the pressure pump 1300 rotates in one direction or another, the hydraulic piston 1320 moves to one side or the other, thereby generating pressure in the first pressure chamber 1330 or the second pressure chamber 1340. The pressure discharged from the first pressure chamber 1330 or the second pressure chamber 1340 is transmitted to each wheel cylinder 21, 22, 23, and 24 through the pressure regulating unit 1400, the first hydraulic circuit 1510, and the second hydraulic circuit 1520 to generate braking force.

[0066] Specifically, the first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b are kept in the open state. In addition, the first to fourth outlet valves 1512a, 1512b, 1522a, and 1522b are switched to the closed state to prevent the pressure of the pressurized medium from leaking to the first outlet flow path 1610 or the second outlet flow path 1620.

[0067] On the other hand, as the hydraulic piston 1320 shifts, a negative pressure is generated in either the first pressure chamber 1330 or the second pressure chamber 1340. The pressure transfer unit 1700 operates to supply the pressurized medium stored in the reservoir 1100 to either the first pressure chamber 1330 or the second pressure chamber 1340 that generates the negative pressure.

[0068] Figure 3This is a diagram illustrating the control-related structures and signal and power flow of the electronic braking system according to a first embodiment of the present invention. (Refer to...) Figure 3 It provides a more detailed explanation of the structure, signal, and power flow related to the control of the electronic braking system.

[0069] In a first embodiment of the present invention, a first control unit 130 and a second control unit 140 are included as lower-level structures that can serve as the autonomous driving-related control module A. Furthermore, the first control unit 130 and the second control unit 140 may have independent power supplies. That is, the first control unit 130 receives power from a first power supply B1, and the second control unit 140 may receive power from a second power supply B2. Accordingly, when the pedal position actuator 120 is controlled by the first control unit 130, the first power supply B1 is supplied to the pedal position actuator 120; when the pedal position actuator 120 is controlled by the second control unit 140, the second power supply B2 may be supplied to the pedal position actuator 120. This ensures redundancy in power supply and improves reliability. On the other hand, the first power supply B1 and the second power supply B2 may each be composed of batteries.

[0070] When the vehicle enters autonomous driving mode, a request to move the brake pedal 10 to the second position is generated by the autonomous driving control-related structure. This request is received by the first control unit 130 or the second control unit 140, which then generates a control signal for the pedal position actuator 120. At this time, the request to move the brake pedal 10 to the second position can also be transmitted to the autonomous driving-related control module A (R1) via the vehicle's CAN (C), or it can be transmitted directly from the autonomous driving ECU or chassis domain controller to the autonomous driving-related control module A (R2).

[0071] On the other hand, regarding the control of the motor 1380 of the pressure pump 1300, the first control unit 130 and the second control unit 140 can receive information related to the rotational position of the motor 1380 from the motor position sensor (MPS) of the motor 1380. Based on this, the first control unit 130 and the second control unit 140 can send control signals for the motor 1380. Additionally, the first control unit 130 and the second control unit 140 can also control the motors P1 and P2 of the electronic parking brake. More specifically, the first control unit 130 controls the motor P1 of the first electronic parking brake, and the second control unit 140 controls the motor P2 of the second electronic parking brake. For example, the first electronic parking brake can be installed on the left wheel of the vehicle, and the second electronic parking brake can be installed on the right wheel of the vehicle.

[0072] As described above, the first control unit 130 and the second control unit 140 can control the motors P1 and P2 of the vehicle's parking brake, in addition to the motors 1380 of the pressure pump 1300 and the drive motors of the pedal position actuator 120. In this case, the first control unit 130 and the second control unit 140 are configured with independent drive circuits for each motor. Accordingly, in the first embodiment of the present invention, when controlling the pedal position actuator 120, the drive of the motor 1380 of the pressure pump 1300 and the drive of the motors P1 and P2 of the parking brake are not affected.

[0073] On the other hand, the first control unit 130 and the second control unit 140 are configured in a single control module package and can be configured with independent PCBs.

[0074] Figure 4 This is a structural diagram of the electronic braking system according to the second embodiment of the present invention.

[0075] Reference Figure 4 The electronic braking system of the second embodiment of the present invention may include: a pedal unit 2000A connected to the brake pedal 10 and operated by the driver's pedal force; and a brake operation unit 2000B that generates pressure for the pressurized medium used for vehicle braking based on a signal output corresponding to the displacement of the brake pedal 10. In this case, the displacement of the brake pedal 10 can be detected by a pedal displacement sensor 11, and the signal can be an electrical signal output by the pedal displacement sensor 11.

[0076] The pedal unit 2000A includes a pedal displacement actuator 220, which displaces the brake pedal 10 from a first position to a second position when entering an autonomous driving mode where driver braking is not required. For example, the first position is a position provided to allow the driver to operate the brake pedal 10, and the second position can be a position where the brake pedal 10 is moved away from the driver's seat to improve the utilization of legroom in the driver's seat.

[0077] Figure 5 This is a diagram illustrating the change of the brake pedal from a first position to a second position in the electronic braking system of a second embodiment of the present invention. (Refer to...) Figure 5 In a second embodiment of the present invention, the second position may be a position where the brake pedal 10 is linearly displaced a predetermined distance toward the front of the vehicle. On the other hand, when the driver needs to brake at the end of the autonomous driving mode, the pedal displacement actuator 220 can displace the brake pedal 10 from the second position to the first position.

[0078] The braking operation unit 2000B includes a first control unit 230 and a second control unit 240. Similar to the description in the first embodiment of the present invention, the first control unit 230 and the second control unit 240 control the pedal displacement actuator 220. When entering the autonomous driving mode, the first control unit 230 controls the pedal displacement actuator 220 to move the brake pedal 10 from a first position to a second position. Additionally, when the autonomous driving mode ends and driver braking is required, the first control unit 230 can control the pedal displacement actuator 220 to move the brake pedal 10 from the second position to the first position. Conversely, if the first control unit 230 fails to control the pedal displacement actuator, the second control unit 240 can control the pedal displacement actuator 220.

[0079] In the second embodiment of the present invention, the first control unit 230 and the second control unit 240 can transmit control signals for the pedal position actuator 220 to the pedal position actuator 120 via the vehicle's CAN(C). Furthermore, the first control unit 230 and the second control unit 240 can be directly connected to the pedal position actuator 220 via the first line W1 and the second line W2, respectively. Additionally, the control-related structures, signal and power flow of the electronic braking system of the first embodiment of the present invention can also be directly applied to the second embodiment.

[0080] On the other hand, the reservoir 2100, pressure pump 2300, pressure regulating unit 2400, first and second hydraulic circuits 2510 and 2520, and pressure transfer unit 2700 of the brake operation unit 2000B are the same as those described in the first embodiment of the present invention. The structure of the pressure pump 2300, namely the cylinder 2310 forming pressure chambers 2330 and 2340 inside, the hydraulic piston 2320, the sealing components 1350a and 1350b, the motor 2380, and the drive shaft 2390, are also the same as those in the first embodiment of the present invention. In addition, the first and second hydraulic circuits 2510 and 2520 include: first to fourth inlet valves 2511a, 2511b, 2521a, and 2521b; first to fourth check valves 2513a, 2513b, 2523a, and 2523b; and first to fourth outlet valves 2512a, 2512b, 2522a, and 2522b.

[0081] Hereinafter, the structure of the second embodiment of the present invention that differs from that of the first embodiment will be described in detail.

[0082] In a second embodiment of the present invention, the pedal unit 2000A includes a pedal simulator 2200, which generates a reaction force to the driver's pedal force to provide the driver with pedal feel. The pedal simulator 2200 includes: a cylinder body 2210; a single chamber 2220 formed inside the cylinder body 1210; an elastic member 2230 disposed inside the chamber 2220; and a piston 2240 that pressurizes the elastic member 2230 by applying a pedal force to the brake pedal 10. Furthermore, in addition to the elastic member 2230, the chamber 2220 is also filled with a pressurizing medium F. For example, the pressurizing medium F can be brake fluid. The pressurizing medium F filling the chamber 2220 can be the same as the pressurizing medium of the brake operating unit 2000B. Additionally, the pedal simulator 2200 may also include an auxiliary reservoir 2250, which flows through the cylinder body 2210 to supply fluid to the cylinder body 2210, or stores pressurized medium F recovered from the cylinder body 2310.

[0083] As described above, the pedal simulator 2200, which is filled with pressurized medium F inside chamber 2220, can be configured as a wet type. When the pedal simulator 2200 is configured as a wet type, in the reversing mode of the brake operating unit 2000B, the pressurized medium F filled in chamber 2220 of the pedal simulator 2200 can be supplied to the brake operating unit 2000B. Here, the reversing mode refers to the situation where the pressure pump 2300 of the brake operating unit 2000B cannot normally provide braking force. When the pressure pump 2300 of the brake operating unit 2000B normally provides braking force, the pressurized medium F filled in chamber 2220 of the pedal simulator 2200 is not supplied to the wheel cylinders. However, when the pressure pump 2300 of the brake operating unit 2000B cannot supply braking force, the pressurized medium F inside chamber 2220 can supply hydraulic pressure to at least one wheel cylinder through the third hydraulic circuit 2800 described later.

[0084] In response, the brake operation unit 2000B may include a third hydraulic circuit 2800. When braking force cannot be provided by the pressure pump 2300 of the brake operation unit 2000B, the third hydraulic circuit 2800 supplies the pressure of the pressurized medium generated by the pedal simulator 2200 to at least one of the first to fourth wheel cylinders 21, 22, 23, and 24. In a second embodiment of the invention, when the pressure pump 2300 fails to generate pressure for the pressurized medium, or when the pressure of the pressurized medium cannot be supplied to the first to fourth wheel cylinders 21, 22, 23, and 24 via the first hydraulic circuit 2510 and the second hydraulic circuit 2520, the first control unit 230 or the second control unit 240 may control the third hydraulic circuit 2800 to supply the pressure of the pressurized medium F generated by the pedal simulator 2200 to at least one of the first to fourth wheel cylinders 21, 22, 23, and 24.

[0085] More specifically, the third hydraulic circuit 2800 may include: a first backup flow path 2810, connecting the pedal simulator 2200 and the first wheel cylinder 21; and a second backup flow path 2820, connecting the pedal simulator 2200 and the fourth wheel cylinder 24. A first shut-off valve 2811 may be configured in the first backup flow path 2810, and a second shut-off valve 2821 may be configured in the second backup flow path 2820.

[0086] Under normal conditions, the first shut-off valve 2811 and the second shut-off valve 2821 are closed, disconnecting the pedal simulator 2200 from the first and fourth wheel cylinders 21 and 24. If braking force cannot be provided via the pressure pump 2300, the first shut-off valve 2811 and the second shut-off valve 2821 are opened, allowing the pedal simulator 2200 to supply pressurized medium F to the first and fourth wheel cylinders 21 and 24. For example, the first wheel cylinder 21 and the fourth wheel cylinder 24 can be respectively located on the front left and front right wheels of the vehicle. That is, even if braking force cannot be provided via the pressure pump 2300, pressure is still provided from the pedal simulator 2200 to the front two wheels of the vehicle, thus ensuring safety at a minimum.

[0087] On the other hand, the auxiliary reservoir 2250 and the reservoir 2100 can be connected via the auxiliary flow path 2260. Although not in Figure 4 As shown, a valve may also be configured in the auxiliary flow path 2260, and the valve is opened only when pressure is supplied from the auxiliary reservoir 2250 to the wheel cylinder side, which can connect the auxiliary reservoir 2250 and the reservoir 2100.

[0088] Furthermore, regarding the control of the third hydraulic circuit 2800, namely the control of the first shut-off valve 2811 and the second shut-off valve 2821, the first control unit 230 may perform the control first. Additionally, if the first control unit 230 fails to control the circuit, the second control unit 240 may perform the control.

[0089] Embodiments of the present invention have been described, but the spirit of the invention is not limited to the embodiments presented in this specification. Those skilled in the art who understand the spirit of the invention will readily propose other embodiments by adding, changing, deleting, or adding components, etc., within the same conceptual scope, but these are also included within the spirit scope of the invention.

Claims

1. An electronic braking system, comprising: The pedal unit is connected to the brake pedal and is operated by the driver's pedaling force; and The braking operation unit generates the pressure of the pressurized medium for braking the vehicle based on the signal output corresponding to the displacement of the brake pedal. The pedal unit includes a pedal displacement actuator, which displaces the brake pedal from a first position to a second position when entering an autonomous driving mode where the driver's braking operation is not required. The braking operation unit includes: a first control unit that controls the generation of the pressure; and a second control unit that controls the generation of the pressure together with the first control unit, or takes over the control of the pressure generation in the event of a failure of the first control unit. When entering the autonomous driving mode, the first control unit or the second control unit controls the pedal displacement actuator to move the brake pedal from the first position to the second position. The first control unit and the second control unit send control signals for the pedal position actuator to the pedal position actuator via the vehicle's controller area network, i.e., CAN. The first control unit is directly connected to the pedal position actuator via a first line, and the second control unit is directly connected to the pedal position actuator via a second line. In the event that the control signal fails to be transmitted via the CAN bus, the first control unit or the second control unit transmits the control signal directly to the pedal position actuator via the first line or the second line.

2. The electronic braking system according to claim 1, characterized in that, The second position is the same as the position of the brake pedal when the brake pedal is pressed with a predetermined force.

3. The electronic braking system according to claim 1, characterized in that, The second position is the position where the brake pedal is linearly displaced forward of the vehicle.

4. The electronic braking system according to claim 1, characterized in that, When the driver needs to brake to end the autonomous driving mode, the first control unit controls the pedal displacement actuator to move the brake pedal from the second position to the first position.

5. The electronic braking system according to claim 1, characterized in that, When entering the autonomous driving mode, if the first control unit fails to control the pedal displacement actuator, the second control unit controls the pedal displacement actuator to move the brake pedal from the first position to the second position.

6. The electronic braking system according to claim 1, characterized in that, The braking operation unit also includes a pressure pump, which generates the pressure of the pressurizing medium according to the signal; The first control unit controls a portion of the power of the pressure pump, and the second control unit controls the remaining power of the pressure pump.

7. The electronic braking system according to claim 6, characterized in that, In the event of a failure in either the first control unit or the second control unit, the remaining control unit generates additional power and controls the pressure pump.

8. The electronic braking system according to claim 7, characterized in that, The braking operation unit further includes: a first hydraulic circuit for controlling the flow of pressurized medium supplied to the first wheel cylinder and the second wheel cylinder; and a second hydraulic circuit for controlling the flow of pressurized medium supplied to the third wheel cylinder and the fourth wheel cylinder; The first control unit first controls the first hydraulic circuit and the second hydraulic circuit. In the event of a failure of the first control unit, the second control unit controls the first hydraulic circuit and the second hydraulic circuit.

9. The electronic braking system according to claim 8, characterized in that, The pedal unit also includes a master cylinder, which generates pressure of the pressurizing medium according to the pedal force; The braking unit further includes a third hydraulic circuit, which provides the pressure of the pressurized medium generated in the master cylinder to at least one of the first to fourth wheel cylinders.

10. The electronic braking system according to claim 9, characterized in that, In the event that the pressure of the pressurizing medium cannot be generated by the pressure pump, or that the pressure of the pressurizing medium cannot be supplied to the first to fourth wheel cylinders through the first and second hydraulic circuits. The first control unit or the second control unit controls the third hydraulic circuit to provide pressure of the pressurized medium generated in the master cylinder to at least one of the first to fourth wheel cylinders.

11. The electronic braking system according to claim 1, characterized in that, The pedal unit and the braking operation unit are physically separate from each other.

12. The electronic braking system according to claim 1, characterized in that, The pedal unit also includes a pedal simulator that generates a reaction force in response to the pedaling force to provide pedal feel to the driver.

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