Electronic brake system and method of operating same

Abstract

An electronic brake system and a method of operating the same are disclosed. The disclosed electronic brake system includes: a reservoir storing a pressurized medium; the integrated master cylinder comprises a main piston connected with the brake pedal, a main chamber of which the volume can be changed according to the displacement of the main piston, and a pedal simulator connected with the main piston to provide a treading feeling; a hydraulic pressure supply device that operates the hydraulic piston to generate hydraulic pressure according to an electric signal output in accordance with the displacement of the brake pedal; a first hydraulic circuit that controls the flow of the pressurized medium supplied to the first wheel cylinder and the second wheel cylinder; a second hydraulic circuit that controls the flow of the pressurized medium supplied to the third wheel cylinder and the fourth wheel cylinder; a single backup flow path having one end connected to the main chamber and the other end connected to any one of the first hydraulic circuit and the second hydraulic circuit; a shutoff valve provided in the backup flow path to control the flow of the pressurized medium; and a connection flow path connecting the first hydraulic circuit and the second hydraulic circuit, the other ends of the connection flow path and the backup flow path communicating with each other.

Description

Technical Field

[0001] The present invention relates to an electronic brake system, and more particularly, to an electronic brake system that generates braking force by using an electrical signal corresponding to a brake pedal displacement. Background Art

[0002] A vehicle must be equipped with a brake system for performing braking, and for the safety of a driver and passengers, various types of brake systems have been proposed.

[0003] Conventional braking systems primarily utilize a mechanically connected booster to supply the required braking fluid to the wheel cylinders when the driver depresses the brake pedal. However, with increasing market demand for various braking functions that precisely respond to vehicle operating conditions, electronic braking systems have become increasingly popular in recent years. These systems receive the driver's braking intent via an electrical signal from a pedal displacement sensor that detects the brake pedal's displacement. Based on this signal, the hydraulic pressure supply device operates to supply the required braking fluid to the wheel cylinders.

[0004] These electronic braking systems generate and provide braking information in response to the driver's brake pedal operation in normal operation mode or during autonomous vehicle operation using electrical signals. Based on these signals, they electrically operate and control the hydraulic pressure supply device, generating the required braking hydraulic pressure and transmitting it to the wheel cylinders. As described above, these electronic braking systems and operating methods are electrically operated and controlled, enabling complex and diverse braking actions. However, technical problems with electronic components can lead to instability in generating the required braking hydraulic pressure, potentially posing a threat to passenger safety.

[0005] Therefore, when components malfunction or become uncontrollable, the electronic brake system enters an abnormal operating mode. In this case, a mechanism is required to directly link the driver's brake pedal application to the wheel cylinders. Specifically, in the electronic brake system's abnormal operating mode, the hydraulic pressure required for braking must be generated immediately upon the driver's application of brake pedal force and transmitted directly to the wheel cylinders.

[0006] Furthermore, a solution is needed to enable the electronic brake system to stably achieve braking not only in a normal operation mode but also in an abnormal operation mode while minimizing configurations such as hydraulic flow paths and valves provided within the system.

[0007] Prior art document: Korean Patent Publication No. 2023-0133072 (September 19, 2023) Summary of the Invention

[0008] Problems to be solved by the invention

[0009] This embodiment aims to provide an electronic brake system that can effectively achieve braking under various operating conditions.

[0010] This embodiment aims to provide an electronic brake system that can achieve braking through a simple structure and operation.

[0011] The present embodiment aims to provide an electronic brake system capable of reducing noise generated during braking by reducing the number of valves.

[0012] This embodiment aims to provide an electronic brake system capable of reducing costs by reducing the number of components.

[0013] Means used to solve problems

[0014] According to one aspect of the present invention, an electronic braking system includes: a reservoir for storing pressurized medium; an integrated master cylinder including a main piston connected to a brake pedal, a main chamber whose volume can change according to the displacement of the main piston, and a pedal simulator connected to the main piston to provide a pedaling feel; a hydraulic supply device that operates the oil pressure piston according to an electrical signal output corresponding to the displacement of the brake pedal to generate hydraulic pressure; a first oil pressure circuit that controls the flow of pressurized medium supplied to the first wheel cylinder and the second wheel cylinder; a second oil pressure circuit that controls the flow of pressurized medium supplied to the third wheel cylinder and the fourth wheel cylinder; a single backup flow path, one end of which is connected to the main chamber and the other end of which is connected to any one of the first oil pressure circuit and the second oil pressure circuit; a shut-off valve that is arranged in the backup flow path to control the flow of pressurized medium; and a connecting flow path that connects the first oil pressure circuit and the second oil pressure circuit, and the other ends of the connecting flow path and the backup flow path are connected to each other.

[0015] The other ends of the connecting flow path and the backup flow path may be directly communicated with each other without the intervention of a valve.

[0016] The integrated master cylinder may include: a first master piston connected to the brake pedal; a second master piston configured to be displaced according to the displacement of the first master piston; a first master chamber whose volume can be changed according to the displacement of the first master piston; and a second master chamber whose volume can be changed according to the displacement of the second master piston, and one end of the backup flow path is connected to the second master chamber.

[0017] The pedal simulator may be disposed between the first master piston and the second master piston.

[0018] According to one aspect of the present invention, the electronic braking system may further include: an oil pressure control device, which is arranged between the hydraulic supply device and the first oil pressure circuit and the second oil pressure circuit to regulate the flow of the pressurized medium, and the first oil pressure circuit and the second oil pressure circuit respectively include at least one inlet valve, and the inlet valve is used to control the flow of the pressurized medium transmitted to at least one of the first wheel cylinder to the fourth wheel cylinder, and the connecting flow path can be arranged between the rear end of the oil pressure control device and the front end of the inlet valve.

[0019] The hydraulic supply device includes a first pressure chamber arranged in front of the oil pressure piston and a second pressure chamber arranged behind the oil pressure piston. The oil pressure control device may include a first oil pressure flow path connecting the first pressure chamber and the connecting flow path, a second oil pressure flow path connecting the second pressure chamber and the connecting flow path, a third oil pressure flow path connected to the first oil pressure flow path at one end and connected to the second oil pressure flow path at the other end, and a fourth oil pressure flow path connecting the third oil pressure flow path and the connecting flow path.

[0020] The oil pressure control device may include a first valve arranged in the first oil pressure flow path to control the flow of the pressurized medium, a second valve arranged in the second oil pressure flow path to control the flow of the pressurized medium, a third valve arranged in the third oil pressure flow path and between one end and the connection part of the fourth oil pressure flow path, and a fourth valve arranged in the third oil pressure flow path and between the other end and the connection part of the fourth oil pressure flow path.

[0021] The first valve may be configured as a check valve that only allows the flow of pressurized medium discharged from the first pressure chamber, the second valve may be configured as a check valve that only allows the flow of pressurized medium discharged from the second pressure chamber, and the third valve and the fourth valve may be configured as solenoid valves that control the bidirectional flow of pressurized medium.

[0022] The electronic brake system according to one aspect of the present invention may further include a first reservoir flow path connecting the reservoir and the second master chamber.

[0023] The first main chamber may be configured as a dry type that does not contain a pressurized medium.

[0024] The electronic brake system according to one aspect of the present invention may further include: a second reservoir flow path connecting the reservoir and the first main chamber.

[0025] The electronic brake system according to one aspect of the present invention may further include a detection sensor configured to detect a liquid level of the pressurized medium contained in the reservoir.

[0026] The electronic brake system according to one aspect of the present invention may further include a dump control portion provided between the reservoir and the hydraulic pressure supply device to control the flow of the pressurized medium.

[0027] The dump control portion may include a first dump control portion controlling the flow of the pressurized medium between the first pressure chamber and the reservoir, and a second dump control portion controlling the flow of the pressurized medium between the second pressure chamber and the reservoir.

[0028] The first dump control portion may include a first dump flow path connecting the first pressure chamber and the reservoir and a first bypass flow path that branches off from the first dump flow path and then rejoins. The second dump control portion may include a second dump flow path connecting the second pressure chamber and the reservoir and a second bypass flow path that branches off from the second dump flow path and then rejoins.

[0029] According to another aspect of the present invention, a method for operating an electronic braking system is provided, wherein a normal operating mode gradually increases as the hydraulic pressure of the pressurized medium transmitted from the hydraulic supply device to the wheel cylinder, including: a first braking mode, supplying hydraulic pressure for a first time; a second braking mode, supplying hydraulic pressure for a second time; and a third braking mode, supplying hydraulic pressure for a third time.

[0030] According to another aspect of the present invention, a method for operating an electronic brake system may be provided, characterized in that in the first braking mode, the oil hydraulic piston moves forward to transfer the pressurized medium contained in the first pressure chamber to the first to fourth wheel cylinders.

[0031] According to another aspect of the present invention, a method for operating an electronic brake system may be provided, characterized in that in the second braking mode, the oil hydraulic piston moves rearward so that the pressurized medium accommodated in the second pressure chamber is transferred to the first to fourth wheel cylinders.

[0032] According to another aspect of the present invention, a method for operating an electronic brake system can be provided, in which, in a third braking mode, the third valve and the fourth valve are opened, and the oil hydraulic piston moves forward again to transfer a portion of the pressurized medium of the first pressure chamber to the first to fourth wheel cylinders, while the remaining pressurized medium of the first pressure chamber is transferred to the second pressure chamber.

[0033] According to another aspect of the present invention, a method for operating an electronic braking system can be provided, which also includes a fallback mode to be switched when the brake of the hydraulic supply device fails. The fallback mode is that the pressurized medium discharged from the integrated master cylinder is completely transferred to the first wheel cylinder to the fourth wheel cylinder through the backup flow path and the connecting flow path.

[0034] Effects of the Invention

[0035] This embodiment provides an electronic brake system that can effectively achieve braking under various operating conditions.

[0036] This embodiment provides an electronic brake system that can achieve braking through a simple structure and operation.

[0037] This embodiment provides an electronic brake system capable of reducing noise generated during braking by reducing the number of valves.

[0038] This embodiment provides an electronic brake system that can reduce costs by reducing the number of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 FIG. 1 is a hydraulic circuit diagram showing an electronic brake system according to a first embodiment of the present invention.

[0040] Figure 2 1 is a hydraulic circuit diagram showing a state in which the electronic brake system according to the first embodiment of the present invention executes a first braking mode.

[0041] Figure 3 1 is a hydraulic circuit diagram showing a state in which the electronic brake system according to the first embodiment of the present invention executes the second brake mode.

[0042] Figure 4 1 is a hydraulic circuit diagram showing a state in which the electronic brake system according to the first embodiment of the present invention executes the third brake mode.

[0043] Figure 5 1 is a hydraulic circuit diagram showing a state in which the electronic brake system according to the first embodiment of the present invention executes a non-normal operation mode (fallback mode).

[0044] Figure 6 FIG. 1 is a hydraulic circuit diagram showing an electronic brake system according to a second embodiment of the present invention.

[0045] Description of Reference Numerals

[0046] 1000, 2000: Electronic braking system

[0047] 1100: Reservoir 1200: Integrated master cylinder

[0048] 1300: Hydraulic supply device 1400: Oil pressure control device

[0049] 1510: First hydraulic circuit 1520: Second hydraulic circuit

[0050] 1600: Alternative flow path 1610: Stop valve

[0051] 1700: Storage channel 1800: Dump control unit

[0052] 1900: Connecting flow path DETAILED DESCRIPTION

[0053] Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. The following embodiments are presented to fully convey the concepts of the present invention to those skilled in the art. The present invention is not limited to the embodiments presented herein and may be implemented in other forms. To clarify the present invention, portions not relevant to the description may be omitted from the drawings, and the dimensions of components may be exaggerated to a certain extent for ease of understanding.

[0054] Figure 1 1 is a hydraulic circuit diagram showing an electronic brake system 1000 according to a first embodiment of the present invention.

[0055] Reference Figure 1 The electronic brake system 1000 of the first embodiment of the present invention includes: a reservoir 1100 for storing a pressurized medium; an integrated master cylinder 1200 for providing a reaction force according to the pedaling force of the brake pedal 10 to the driver while pressurizing and discharging a pressurized medium such as brake oil contained therein; a hydraulic supply device 1300 for receiving the driver's braking intention in the form of an electrical signal via a pedal displacement sensor for detecting the displacement of the brake pedal 10 and generating a hydraulic pressure of the pressurized medium through mechanical operation; an oil pressure control device 1400 for controlling the hydraulic pressure supplied from the hydraulic supply device 1300; oil pressure circuits 1510 and 1520 including wheel cylinders 20 for receiving the hydraulic pressure of the pressurized medium to perform braking of each wheel (RR, RL, FR, FL); a dump control unit 1800 provided between the hydraulic supply device 1300 and the reservoir 1100 for controlling the flow of the pressurized medium; and a backup flow path. a reservoir flow path 1700, hydraulically connecting the reservoir 1100 to the integrated master cylinder 1200; and an electronic control unit (ECU, not shown), controlling the hydraulic supply device 1300 and various valves according to the hydraulic information and the pedal displacement information.

[0056] The integrated master cylinder 1200 is configured to provide a reaction force to the driver when the driver applies a pedaling force to the brake pedal 10 to perform a braking operation, thereby providing a stable pedaling feel and pressurizing and discharging the pressurized medium contained inside through the operation of the brake pedal 10.

[0057] The integrated master cylinder 1200 includes a simulation part that provides a pedaling feel to the driver and a main cylinder part that pressurizes and discharges the pressurized medium contained inside according to the pedaling force of the brake pedal, and the simulation part and the main cylinder part can be arranged on the same axis within a cylinder body 1210.

[0058] Specifically, the integrated master cylinder 1200 may include: a cylinder body 1210 having a chamber formed therein; a first master chamber 1220a formed at an inlet side of the cylinder body 1210 connected to the brake pedal 10; a first master piston 1220 disposed in the first master chamber 1220a and connected to the brake pedal 10 so as to be displaced according to the operation of the brake pedal 10; a second master chamber 1230a formed in the cylinder body 1210 at an inner side or a front side (in order to Figure 1 a second master piston 1230, which is disposed in the second master chamber 1230a and can be displaced according to the displacement of the first master piston 1220 or the hydraulic pressure of the pressurized medium contained in the first master chamber 1220a; and a pedal simulator 1240, which is arranged between the first master piston 1220 and the second master piston 1230 to provide a pedaling feel through the elastic restoring force generated during compression.

[0059] The first master chamber 1220a and the second master chamber 1230a can be opened from the brake pedal 10 side (with Figure 1 as the reference) to the inside (with Figure 1 Furthermore, the first and second master pistons 1220 and 1230 are disposed in the first and second master chambers 1220a and 1230a, respectively, and can form hydraulic pressure or negative pressure in the pressurized medium contained in each chamber according to forward and backward movement.

[0060] The cylinder body 1210 may include a large diameter portion 1211 having a first main chamber 1220a formed therein and having a relatively large inner diameter, and a small diameter portion 1212 having a second main chamber 1230a formed therein and having an inner diameter relatively smaller than the large diameter portion 1211. The large diameter portion 1211 and the small diameter portion 1212 of the cylinder body 1210 may be integrally formed.

[0061] The first main chamber 1220a may be formed at the inlet side or rear side of the cylinder 1210 (in order to Figure 1 On the inner side of the large diameter portion 1211 (on the right side when φ is a reference), the first master piston 1220 connected to the brake pedal 10 through the input rod 12 can be accommodated in the first master chamber 1220a in a manner that allows for reciprocal movement.

[0062] The pressurized medium can flow into and be discharged from the first main chamber 1220a through the first oil pressure port 1280a. The first oil pressure port 1280a is connected to the second reservoir flow path 1720 described later, thereby allowing the pressurized medium to flow from the reservoir 1100 into the first main chamber 1220a or to be discharged from the first main chamber 1220a to the reservoir 1100.

[0063] The first master piston 1220 is accommodated and disposed in the first master chamber 1220a and can be moved forward (by Figure 1 The left direction when the reference is taken as the reference) applies pressure to the pressurized medium contained in the first main chamber 1220a to form hydraulic pressure, or moves backward (with the reference as the reference) to form hydraulic pressure. Figure 1 The first master piston 1220 may include: a first body 1221 formed in a cylindrical shape to be in close contact with the inner circumference of the first master chamber 1220a; and a first flange 1222 formed at the rear end of the first body 1221 (with the Figure 1 The first master piston 1220 can be elastically supported by a first piston spring 1220b, and the first piston spring 1220b can be configured to have one end supported by the front surface of the first flange 1222 (with Figure 1 The left side when it is the reference) is supported and the other end is supported by the outer surface of the cylinder body 1210.

[0064] A first sealing member 1290a may be provided between the outer circumferential surface of the first master piston 1220 and the cylinder body 1210 to isolate the first master chamber 1220a from the outside. The first sealing member 1290a is disposed on the outermost side of the brake pedal side of the inner circumferential surface of the cylinder body 1210 and is positioned within a receiving groove recessed into the inner circumferential surface of the cylinder body 1210 to contact the outer circumferential surface of the first master piston 1220. Thus, the first sealing member 1290a prevents the pressurized medium contained in the first master chamber 1220a from leaking to the outside and prevents foreign matter from entering the first master chamber 1220a.

[0065] The second main chamber 1230a may be formed on the inner side or the front side of the cylinder 1210 (in order to Figure 1 The second master piston 1230 may be reciprocably accommodated in the second master chamber 1230a.

[0066] The pressurized medium can flow into and out of the second main chamber 1230a through the second oil pressure port 1280b and the third oil pressure port 1280c. The second oil pressure port 1280b is connected to the first reservoir flow path 1710 described later so that the pressurized medium contained in the reservoir 1100 can flow into the second main chamber 1230a side.

[0067] The second master piston 1230 is housed and disposed in the second master chamber 1230a, and can form the hydraulic pressure of the pressurized medium contained in the second master chamber 1230a by moving forward, and can form negative pressure in the second master chamber 1230a by moving backward. The second master piston 1230 may include: a second body 1231 formed in a cylindrical shape to be in close contact with the inner circumference of the second master chamber 1230a; and a second flange 1232 at the rear end portion of the second body 1231 (with a Figure 1 The second main body 1231 is provided with a second main body 1232 and a second main body 1233. The second main body 1231 is provided with a second main body 1232 and a second main body 1233. The second main body 1231 is provided with a second main body 1232 and a second main body 1233. Figure 1 The left side when it is the reference is supported and the other end is supported by the inner surface of the cylinder body 1210.

[0068] A second sealing member 1290b may be provided between the outer circumferential surface of the second master piston 1230 and the cylinder body 1210 to seal the first master chamber 1220a from the second master chamber 1230a. The second sealing member 1290b may be disposed in a receiving groove recessed into the inner circumferential surface of the cylinder body 1210 to contact the outer circumferential surface of the second master piston 1230. The second sealing member 1290b may prevent the pressurized medium contained in the first master chamber 1220a from leaking into the second master chamber 1230a.

[0069] A cut-off hole 1230c is provided in the second master piston 1230. The cut-off hole 1230c is connected to the second master chamber 1230a and is connected to the second oil pressure port 1280b and the first reservoir flow path 1710 in a non-operating state, i.e., in a standby state before displacement occurs. In addition, a third sealing member 1290c may be provided between the outer circumferential surface of the second master piston 1230 and the cylinder body 1210 so as to block the flow of pressurized medium from the second master chamber 1230a to the first reservoir flow path 1710 connected to the second oil pressure port 1280b. The third sealing member 1290c is formed in a recess on the inner circumferential surface of the cylinder body 1210 in front of the second oil pressure port 1280b (with a diameter of 1 / 4 of the cylinder body 1210). Figure 1The third sealing member 1290c may be provided in front of the second sealing member 1290b (with Figure 1 as the left side of the reference), and can allow the pressurized medium to flow from the first reservoir flow path 1710 connected to the second oil pressure port 1280b to the second main chamber 1230a, and block the pressurized medium from flowing from the second main chamber 1230a to the second oil pressure port 1280b and the first reservoir flow path 1710.

[0070] The pedal simulator 1240 can be arranged between the first master piston 1220 and the second master piston 1230, and provide the driver with a stepping feel of the brake pedal 10 through its own elastic restoring force. Specifically, the pedal simulator 1240 can be arranged between the front surface of the first master piston 1220 and the rear surface of the second master piston 1230, and can be made of a compressible and expandable elastic material (such as rubber, etc.). The pedal simulator 1240 may include: a main body, a cylindrical shape, at least a portion of which is inserted into and supported on the front surface of the first master piston 1220; and a conical portion, at least a portion of which is inserted into and supported on the rear surface of the second master piston 1230 and which is inclined to the front (with a diameter of 100 mm) as it approaches the front. Figure 1 The diameter of the left side (when the reference is taken) gradually decreases. At least a portion of each end of the pedal simulator 1240 is inserted into the first master piston 1220, providing stable support. Furthermore, by utilizing the tapered portion to change the elastic restoring force according to the degree of depression force on the brake pedal 10, a stable and familiar pedaling feel can be provided to the driver.

[0071] The pedal simulation operation of the integrated master cylinder 1200 will be described below. In normal operation mode, the driver operates the brake pedal 10 while shutoff valve 1610, located in the backup flow path 1600 (described later), is closed. As the brake pedal 10 is operated, the first master piston 1220 moves forward. However, as shutoff valve 1610 is closed, the second master chamber 1230a is sealed, preventing the second master piston 1230 from moving. At this point, the pressurized medium contained in the first master chamber 1220a flows in through the second reservoir flow path 1720 (described later). When the second master piston 1230 is unable to move forward, the first master piston 1220 continues to move forward, compressing the pedal simulator 1240. This allows the elastic restoring force of the pedal simulator 1240 to be transmitted to the driver as a pedaling feel. Then, when the driver releases the pedaling force of the brake pedal 10, the first master piston 1220, the second master piston 1230 and the pedal simulator 1240 are restored to their original shapes and return to their original positions due to the elastic restoring force of the first piston spring 1220b and the second piston spring 1230b and the pedal simulator 1240, and the pressurized medium is supplied from the reservoir 1100 to the first master chamber 1220a through the second reservoir flow path 1720, so that the first master chamber 1220a can be filled.

[0072] As described above, since the interiors of the first master chamber 1220a and the second master chamber 1230a are always filled with pressurized medium, the friction between the first master piston 1220 and the second master piston 1230 is minimized during the pedal simulation operation, thereby improving the durability of the integrated master cylinder 1200 and blocking the influx of foreign matter from the outside.

[0073] The reservoir 1100 may accommodate and store a pressurized medium therein, and may supply or receive the pressurized medium by being connected to each component such as the integrated master cylinder 1200 , a hydraulic supply device 1300 described later, and an oil pressure circuit described later.

[0074] The reservoir flow path 1700 is provided to connect the integrated master cylinder 1200 and the reservoir 1100 .

[0075] The reservoir flow path 1700 may include a second reservoir flow path 1720 connecting the first master chamber 1220a and the reservoir 1100, and a first reservoir flow path 1710 connecting the second master chamber 1230a and the reservoir 1100. To this end, the second reservoir flow path 1720 may communicate with the first master chamber 1220a at one end via the first oil pressure port 1280a of the integrated master cylinder 1200, and with the reservoir 1100 at the other end. Furthermore, the first reservoir flow path 1710 may communicate with the second master chamber 1230a at one end via the second oil pressure port 1280b of the integrated master cylinder 1200, and with the reservoir 1100 at the other end. Furthermore, the second reservoir flow path may also communicate with the first master chamber 1220a at one end via the first oil pressure port 1280a of the integrated master cylinder 1200, and with the first reservoir flow path 1710 at the other end.

[0076] The hydraulic pressure supply device 1300 is configured to receive a driver's braking intention in the form of an electrical signal from a pedal displacement sensor for detecting displacement of the brake pedal 10 , and generate hydraulic pressure of a pressurized medium through a mechanical operation.

[0077] The hydraulic supply device 1300 may include: a hydraulic supply unit that provides pressurized medium pressure to be transmitted to the wheel cylinder 20; a motor (not shown) that generates rotational force through an electrical signal from a pedal displacement sensor; and a power conversion unit (not shown) that converts the rotational motion of the motor into linear motion to transmit it to the hydraulic supply unit.

[0078] The hydraulic supply unit includes: a cylinder 1310 configured to accommodate a pressurized medium, an oil hydraulic piston 1320 accommodated in the cylinder 1310, a sealing member 1350 arranged between the oil hydraulic piston 1320 and the cylinder 1310 to seal the pressure chambers 1330 and 1340, and a drive shaft 1390 that transmits the power output by the power conversion unit to the oil hydraulic piston 1320.

[0079] The pressure chambers 1330 and 1340 may include: a first pressure chamber 1330 located in front of the oil pressure piston 1320 (with Figure 1 and a second pressure chamber 1340, located behind the hydraulic piston 1320 (with Figure 1 That is, the first pressure chamber 1330 is configured to be divided by the cylinder body 1310 and the front surface of the oil piston 1320 so that its volume changes with the movement of the oil piston 1320, and the second pressure chamber 1340 is configured to be divided by the cylinder body 1310 and the rear surface of the oil piston 1320 so that its volume changes with the movement of the oil piston 1320.

[0080] The first pressure chamber 1330 is connected to a first oil pressure path 1401 described later via a first communication hole 1360 a formed in the cylinder 1310 , and the second pressure chamber 1340 is connected to a second oil pressure path 1402 described later via a second communication hole 1360 b formed in the cylinder 1310 .

[0081] The sealing members include a piston sealing member 1350a, which is provided between the oil pressure piston 1320 and the cylinder body 1310 to seal between the first pressure chamber 1330 and the second pressure chamber 1340; and a drive shaft sealing member 1350b, which is provided between the drive shaft 1390 and the cylinder body 1310 to seal the opening between the second pressure chamber 1340 and the cylinder body 1310. The hydraulic pressure or negative pressure in the first pressure chamber 1330 and the second pressure chamber 1340 generated by the forward or backward movement of the oil pressure piston 1320 is sealed by the piston sealing member 1350a and the drive shaft sealing member 1350b to prevent leakage and is transmitted to the first and second oil pressure flow paths 1401 and 1402, which will be described later.

[0082] A motor (not shown) is configured to generate a driving force for the oil pressure piston 1320 by an electrical signal output by an electronic control unit (ECU). The motor may be configured to include a stator and a rotor, and by rotating forward or backward, thereby providing power to change the displacement of the oil pressure piston 1320. The speed and rotation angle of the motor can be precisely controlled by a motor control sensor. Since the motor is a well-known technology, a detailed description will be omitted.

[0083] The power conversion unit (not shown) is configured to convert the rotational force of the motor into linear motion. As an example, the power conversion unit may be configured to include a worm shaft (not shown), a worm wheel (not shown), and a drive shaft 1390.

[0084] The worm shaft can be integrally formed with the motor's rotating shaft, and a worm can be formed on its outer circumference to mesh with the worm gear, thereby rotating the worm gear. The worm gear can mesh with the drive shaft 1390 to allow the drive shaft 1390 to move linearly. The drive shaft 1390 is connected to the hydraulic piston 1320 to operate as a single unit, thereby allowing the hydraulic piston 1320 to slide within the cylinder 1310.

[0085] To reiterate the above operation, when the pedal displacement sensor detects the displacement of brake pedal 10, the detected signal is transmitted to the electronic control unit, which drives the motor to rotate the worm shaft in one direction. The rotational force of the worm shaft is transmitted to drive shaft 1390 through the worm gear. The oil pressure piston 1320 connected to drive shaft 1390 moves forward within cylinder 1310, generating hydraulic pressure in first pressure chamber 1330.

[0086] Conversely, when the brake pedal 10 is released, the electronic control unit drives the motor to rotate the worm shaft in the opposite direction. Consequently, the worm wheel also rotates in the opposite direction, and the hydraulic piston 1320 connected to the drive shaft 1390 moves backward within the cylinder 1310, generating negative pressure in the first pressure chamber 1330.

[0087] The generation of hydraulic pressure and negative pressure in second pressure chamber 1340 can be achieved by operating in the opposite direction to that described above. Specifically, when the pedal displacement sensor detects displacement of brake pedal 10, the detected signal is transmitted to the electronic control unit, which drives the motor to rotate the worm shaft in the opposite direction. The rotational force of the worm shaft is transmitted to drive shaft 1390 via the worm gear. The hydraulic piston 1320 connected to drive shaft 1390 generates hydraulic pressure in second pressure chamber 1340 by moving backward within cylinder 1310.

[0088] Conversely, when the brake pedal 10 is released, the electronic control unit drives the motor in one direction, causing the worm shaft to rotate in one direction. Consequently, the worm wheel also rotates in the opposite direction, and the hydraulic piston 1320 connected to the drive shaft 1390 moves forward within the cylinder 1310, generating negative pressure in the second pressure chamber 1340.

[0089] As described above, hydraulic pressure supply device 1300 can generate hydraulic pressure or negative pressure in first pressure chamber 1330 and second pressure chamber 1340, respectively, depending on the rotational direction of the worm shaft when the motor is driven. Furthermore, a control valve can be used to determine whether to transmit hydraulic pressure for braking or to release the brake using negative pressure. A detailed description of this will be provided later.

[0090] On the other hand, the power conversion part according to this embodiment is not limited to any one structure as long as it can convert the rotational motion of the motor into the linear motion of the oil hydraulic piston 1320, and even if it is implemented by devices of various structures and methods, it should be understood in the same way.

[0091] The hydraulic supply device 1300 can be hydraulically connected to the reservoir 1100 via a dump control unit 1800. The dump control unit can be disposed between the reservoir and the hydraulic supply device to control the flow of pressurized medium. The dump control unit 1800 may include a first dump control unit for controlling the flow of pressurized medium between a first pressure chamber 1330 and the reservoir 1100; and a second dump control unit for controlling the flow of pressurized medium between the second pressure chamber 1340 and the reservoir 1100. The first dump control unit may include a first dump flow path 1810 connecting the first pressure chamber 1330 and the reservoir 1100, and a first bypass flow path 1830 that branches off from the first dump flow path 1810 and then rejoins. The second dump control unit may include a second dump flow path 1820 connecting the second pressure chamber 1340 and the reservoir 1100, and a second bypass flow path 1840 that branches off from the second dump flow path 1820 and then rejoins.

[0092] A first dump check valve 1811 and a first dump valve 1831 may be provided in the first dump flow path 1810 and the first bypass flow path 1830, respectively, for controlling the flow of pressurized medium. The first dump check valve 1811 may be configured to only allow the pressurized medium to flow from the reservoir 1100 to the first pressure chamber 1330 and block the flow of pressurized medium in the opposite direction. The first bypass flow path 1830 is connected to the first dump flow path 1810 in parallel with the first dump check valve 1811 and may be provided with the first dump valve 1831 for controlling the flow of pressurized medium between the first pressure chamber 1330 and the reservoir 1100. In other words, the first bypass flow path 1830 may be connected to the first dump flow path 1810, bypassing the front and rear ends of the first dump check valve 1811, and the first dump valve 1831 may be configured as a two-way solenoid valve for controlling the flow of the pressurized medium between the first pressure chamber 1330 and the reservoir 1100. The first dump valve 1831 may be configured as a normally closed solenoid valve that is normally closed and is operated to open the valve upon receiving an electrical signal from the electronic control unit.

[0093] Second dump check valves 1821 and 1841 may be provided on second dump flow path 1820 and second bypass flow path 1840, respectively, for controlling the flow of pressurized medium. Second dump check valve 1821 may be configured to only allow pressurized medium to flow from reservoir 1100 to second pressure chamber 1330 and block flow in the opposite direction. Second bypass flow path 1840 is connected to second dump flow path 1820 in parallel with second dump check valve 1821 and may be provided with second dump valve 1841 for controlling the flow of pressurized medium between second pressure chamber 1330 and reservoir 1100. In other words, the second bypass flow path 1840 may be connected to the second dump flow path 1820, bypassing the front and rear ends of the second dump check valve 1821, and the second dump valve 1841 may be configured as a two-way solenoid valve for controlling the flow of the pressurized medium between the second pressure chamber 1330 and the reservoir 1100. The second dump valve 1841 may be configured as a normally open solenoid valve that is normally open and is operated to close the valve upon receiving an electrical signal from the electronic control unit.

[0094] The oil pressure circuit may be provided to control the flow of hydraulic pressure supplied to the wheel cylinders, and may include a first oil pressure circuit 1510 and a second oil pressure circuit 1520 .

[0095] The first hydraulic circuit 1510 can control the hydraulic pressure of the first wheel cylinder 21 and the second wheel cylinder 22, which are two wheel cylinders 20 among the four wheels (RR, RL, FR, FL), and the second hydraulic circuit 1520 can control the hydraulic pressure of the third wheel cylinder 23 and the fourth wheel cylinder 24, which are the other two wheel cylinders 20.

[0096] The connecting flow path 1900 may be provided to connect the first oil pressure circuit 1510 and the second oil pressure circuit 1520. The connecting flow path 1900 may be provided between the rear end of the oil pressure control device 1400 (to be described later) and the front ends of the inlet valves 1511a, 1511b, 1521a, and 1521b of the first oil pressure circuit 1510 and the second oil pressure circuit 1520 (to be described later). The connecting flow path 1900 may be connected to the oil pressure flow path of the oil pressure control device 1400 to transfer pressurized medium supplied by the hydraulic supply device to the first oil pressure circuit 1510 or the second oil pressure circuit 1520. Furthermore, the connecting flow path 1900 may be connected to the backup flow path 1600 (to be described later) to transfer pressurized medium supplied by the hydraulic supply device 1300 to the first oil pressure circuit 1510 or the second oil pressure circuit 1520.

[0097] The first hydraulic circuit 1510 can receive or discharge hydraulic pressure through the connecting flow path 1900. Figure 1As shown, the connecting flow path 1900 on the first hydraulic circuit side may be provided to branch into two flow paths connected to the first wheel cylinder 21 and the second wheel cylinder 22. In addition, the second hydraulic circuit 1520 may receive or discharge hydraulic pressure through the connecting flow path 1900. For this purpose, as shown in FIG. Figure 1 As shown, connecting flow path 1900 on the second hydraulic circuit side may be provided to branch into two flow paths connected to third wheel cylinder 23 and fourth wheel cylinder 24 .

[0098] The first to second hydraulic circuits 1510 and 1520 may include at least one inlet valve to control the flow and hydraulic pressure of the pressurized medium delivered to the first to fourth wheel cylinders 21, 22, 23, and 24. Specifically, the first to second hydraulic circuits 1510 and 1520 may include first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b, respectively. The first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b are respectively arranged upstream of the first to fourth wheel cylinders 21, 22, 23, and 24 and may be configured as normally open solenoid valves that are normally open and are operated to close the valves in response to an electrical signal from an electronic control unit.

[0099] The first to second hydraulic circuits 1510 and 1520 may include first to fourth check valves 1513a, 1513b, 1523a, and 1523b connected in parallel to the first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b. The check valves 1513a, 1513b, 1523a, and 1523b may be provided in bypass flow paths connecting the first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b on the first and second hydraulic circuits 1510 and 1520, respectively, to allow only the flow of pressurized medium from each wheel cylinder 20 to the hydraulic supply device 1300 and block the flow of pressurized medium from the hydraulic supply device 1300 to the wheel cylinders 20. The hydraulic pressure of the pressurized medium applied to each wheel cylinder 20 can be quickly released through the first to fourth check valves 1513a, 1513b, 1523a, and 1523b, and even if the first to fourth inlet valves 1511a, 1511b, 1521a, and 1521b do not operate normally, the hydraulic pressure of the pressurized medium applied to the wheel cylinder 20 can be smoothly restored to the hydraulic supply unit.

[0100] First hydraulic circuit 1510 and second hydraulic circuit 1520 may include at least one outlet valve to control the flow of pressurized medium discharged from first to fourth wheel cylinders 21, 22, 23, 24, thereby improving performance when brakes on first to fourth wheel cylinders 21, 22, 23, 24 are released. Specifically, first to fourth hydraulic circuits 1510, 1520 may include first to fourth outlet valves 1512a, 1512b, 1521a, 1522b, respectively. First to fourth outlet valves 1512a, 1512b, 1521a, 1522b are disposed on the discharge sides of first to fourth wheel cylinders 21, 22, 23, 24, respectively, to control the flow of pressurized medium transferred from first to fourth wheel cylinders 21, 22, 23, 24 to reservoir 1100. First to fourth outlet valves 1512a, 1512b, 1521a, and 1522b may be configured as normally closed solenoid valves that are normally closed and are operated to open when receiving an electrical signal from an electronic control unit. When the vehicle is in anti-lock braking system (ABS) mode, first to fourth outlet valves 1512a, 1512b, 1521a, and 1522b may selectively release the hydraulic pressure of the pressurized medium applied to first and fourth wheel cylinders 23 and 22, transferring the hydraulic pressure to reservoir 1100.

[0101] The hydraulic pressure control device 1400 may be provided between the hydraulic pressure supply device and the first and second hydraulic pressure circuits 1510 and 1520 to control the hydraulic pressure transmitted to each wheel cylinder 20. The hydraulic pressure control device may include a plurality of flow paths and valves to control the hydraulic pressure transmitted from the hydraulic pressure supply device 1300 to the wheel cylinders 20, and an electronic control unit (ECU) may be configured to control the hydraulic pressure supply device 1300 and the various valves based on hydraulic pressure information and pedal displacement information.

[0102] The first oil pressure flow path 1401 may be configured to connect the first pressure chamber 1330 and the connecting flow path 1900 , thereby communicating with the first pressure chamber 1330 , and the second oil pressure flow path 1402 may be configured to connect the second pressure chamber 1340 and the connecting flow path 1900 , thereby communicating with the second pressure chamber 1340 .

[0103] The third oil pressure flow path 1403 can be set to be connected to the first oil pressure flow path 1401 at one end and to the second oil pressure flow path 1402 at the other end so that the first oil pressure flow path 1401 and the second oil pressure flow path 1402 are connected, and the fourth oil pressure flow path 1404 can be set to connect the third oil pressure flow path 1403 and the flow path 1900 so that the first oil pressure flow path 1401 and the second oil pressure flow path 1402 are connected to the connecting flow path 1900 after merging in the third oil pressure flow path 1403.

[0104] A first valve 1411 for controlling the flow of pressurized medium may be provided in the first hydraulic flow path 1401. The first valve 1411 may be configured as a check valve that allows only the flow of pressurized medium discharged from the first pressure chamber 1330 and blocks the flow of pressurized medium in the opposite direction. Furthermore, a second valve 1412 for controlling the flow of pressurized medium may be provided in the second hydraulic flow path 1402. The second valve 1412 may be configured as a check valve that allows only the flow of pressurized medium discharged from the second pressure chamber 1340 and blocks the flow of pressurized medium in the opposite direction.

[0105] A third valve 1413 and a fourth valve 1414 may be provided in the third hydraulic flow path 1403 to control the flow of the pressurized medium. The third valve 1413 may be provided in the third hydraulic flow path 1403 between one end of the third hydraulic flow path 1403 and the connection between the third hydraulic flow path 1403 and the fourth hydraulic flow path 1404. The fourth valve 1414 may be provided in the third hydraulic flow path 1403 between the other end of the third hydraulic flow path 1403 and the connection between the third hydraulic flow path 1403 and the fourth hydraulic flow path 1404. The third valve 1413 and the fourth valve 1414 may be configured as two-way control valves for controlling the flow of the pressurized medium along the third hydraulic flow path 1403. The third valve 1413 and the fourth valve 1414 may be configured as normally closed solenoid valves, which are normally closed and are operated to open the valves in response to an electrical signal from an electronic control unit.

[0106] With this configuration of hydraulic flow paths and valves, the hydraulic control device 1400 can sequentially transmit the hydraulic pressure generated in the first pressure chamber 1330 as the hydraulic piston 1320 moves forward through the first hydraulic flow path 1401 and the connecting flow path 1900 to the first hydraulic circuit 1510 and the second hydraulic circuit 1520. Furthermore, the hydraulic pressure generated in the second pressure chamber 1340 as the hydraulic piston 1320 moves backward can sequentially transmit the hydraulic pressure through the second hydraulic flow path 1402 and the connecting flow path 1900 to the first hydraulic circuit 1510 and the second hydraulic circuit 1520.

[0107] Conversely, the negative pressure generated in the first pressure chamber 1330 as the hydraulic piston 1320 moves backward can sequentially recover the pressurized medium supplied to the first hydraulic circuit 1510 through the first hydraulic flowpath 1401 and the connecting flowpath 1900 to the first pressure chamber 1330, and can sequentially recover the pressurized medium supplied to the second hydraulic circuit 1520 through the second hydraulic flowpath 1402 and the connecting flowpath 1900 to the first pressure chamber 1330. Furthermore, the negative pressure generated in the second pressure chamber 1340 as the hydraulic piston 1320 moves forward can sequentially recover the pressurized medium supplied to the first hydraulic circuit 1510 through the first hydraulic flowpath 1401 and the connecting flowpath 1900 to the first pressure chamber 1340, and can sequentially recover the pressurized medium supplied to the second hydraulic circuit 1520 through the second hydraulic flowpath 1402 and the connecting flowpath 1900 to the second pressure chamber 1340.

[0108] It should be noted that Figure 1 The connection of the oil pressure flow path shown is an example to help understand the present invention and is not limited to this structure. Even if it is connected in various ways and structures, for example, when an additional oil pressure flow path is provided between the first oil pressure flow path 1401 and the second oil pressure flow path 1402 to connect with another oil pressure flow path, or other valves are provided on the oil pressure flow path, etc., it should be understood in the same way.

[0109] The electronic brake system 1000 of the first embodiment of the present invention may include a backup flow path 1600. This allows braking to be achieved by directly supplying pressurized medium discharged from the integrated master cylinder 1200 to the wheel cylinders 20 when the system is unable to operate normally due to a malfunction or other reasons. The mode in which the hydraulic pressure of the integrated master cylinder 1200 is directly transmitted to the wheel cylinders 20 is referred to as an abnormal operating mode, i.e., a fallback mode.

[0110] The backup flow path 1600 may be provided singly to be connected to the master chambers 1220 a and 1230 a of the integrated master cylinder 1200 and any one of the first hydraulic circuit 1510 and the second hydraulic circuit 1520 .

[0111] At least one shutoff valve 1610 may be provided in the backup flow path 1600 to control the bidirectional flow of the pressurized medium. The shutoff valve 1610 may be a normally open solenoid valve that is normally open and is operated to close when receiving an electrical signal from an electronic control unit.

[0112] When shutoff valve 1610 is closed, the pressurized medium in integrated master cylinder 1200 is prevented from being directly transmitted to wheel cylinders 20, and the hydraulic pressure supplied by hydraulic pressure supply device 1300 is also prevented from leaking toward integrated master cylinder 1200. Furthermore, when shutoff valve 1610 is opened, the pressurized medium in integrated master cylinder 1200 is directly supplied to first and second hydraulic circuits 1510, 1520 via backup flow path 1600, thereby enabling braking.

[0113] One end of the backup flow path 1600 may be connected to the main chambers 1220a, 1230a, and the other end may be connected to any one of the first oil pressure circuit 1510 and the second oil pressure circuit 1520. Specifically, Figure 1 As shown, one end of the backup flow path 1600 can be connected to the second main chamber 1230a, and the other end of the backup flow path 1600 is in communication with the connecting flow path 1900. In this case, the other end of the backup flow path 1600 can be directly in communication with the connecting flow path 1900 without a valve therebetween.

[0114] exist Figure 1 In the figure, the backup flow path 1600 is shown as being connected to the connecting flow path 1900 connecting the first oil pressure flow path 1401 and the first oil pressure circuit 1510, but is not limited to this. When the backup flow path 1600 is connected to any part of the connecting flow path 1900, for example, when the backup flow path 1600 is connected to the connecting flow path 1900 connecting the second oil pressure flow path 1402 and the second oil pressure circuit 1520, etc., it should also be understood in the same way.

[0115] As described above, even if the backup flow path 1600 is provided singly, the pressurized medium contained in the main chambers 1220a and 1230a of the integrated master cylinder can be connected to the first hydraulic circuit 1510 and the second hydraulic circuit 1520, and can be connected to the first to fourth wheel cylinders 21, 22, 23, and 24, thereby achieving braking through simple structural operations while reducing costs.

[0116] Electronic brake system 1000 may include a circuit pressure sensor PS1 for detecting the hydraulic pressure of the pressurized medium supplied by hydraulic pressure supply device 1300, and a cylinder pressure sensor PS2 for detecting the hydraulic pressure in second master chamber 1230a. Circuit pressure sensor PS1 is located on the hydraulic circuit side to detect the hydraulic pressure of the pressurized medium contained within the hydraulic circuit, while cylinder pressure sensor PS2 is located between second master chamber 1230a and shutoff valve 1610 on backup flow path 1600 to detect the hydraulic pressure of the pressurized medium contained within second master chamber 1230a.

[0117] The electronic brake system 1000 may include a detection sensor for detecting the liquid level of the pressurized medium contained in the reservoir 1100. Therefore, liquid leakage of the pressurized medium can be detected by the detection sensor (not shown), thereby easily diagnosing whether the pressurized medium, which should be contained and communicated in a plurality of configurations, has leaked to the outside.

[0118] Hereinafter, an operating method of the electronic brake system 1000 according to the first embodiment of the present invention will be described.

[0119] The electronic brake system 1000 according to the first embodiment of the present invention may include: a normal operation mode, in which various components operate normally without failure or abnormality to perform braking; and an abnormal operation mode (fallback mode), in which the vehicle is braked urgently when a failure or abnormality occurs in the brake system.

[0120] Hereinafter, a normal operation mode of the electronic brake system 1000 according to the first embodiment of the present invention will be described.

[0121] In the normal operating mode of the electronic brake system 1000 of the first embodiment of the present invention, as the hydraulic pressure transmitted to the wheel cylinders 20 by the hydraulic pressure supply device 1300 increases, the system can be operated in different braking modes, namely, first through third braking modes. Specifically, in the first braking mode, the hydraulic pressure provided by the hydraulic pressure supply device 1300 is supplied to the wheel cylinders 20 for the first time. In the second braking mode, the hydraulic pressure provided by the hydraulic pressure supply device 1300 is supplied to the wheel cylinders 20 for the second time, thereby transmitting a higher braking pressure than in the first braking mode. In the third braking mode, the hydraulic pressure provided by the hydraulic pressure supply device 1300 is supplied to the wheel cylinders 20 for the third time, thereby transmitting a higher braking pressure than in the second braking mode.

[0122] The first through third braking modes can be changed by varying the operation of hydraulic pressure supply device 1300 and oil pressure control device 1400. By applying the first through third braking modes, hydraulic pressure supply device 1300 can provide a sufficiently high hydraulic pressure for the pressurized medium without requiring a high-specification motor, further preventing unnecessary loads on the motor. Consequently, the cost and weight of the braking system can be reduced while ensuring stable braking force, and the durability and operational reliability of the system can be improved.

[0123] Figure 2 1 is a hydraulic circuit diagram showing a state in which the electronic brake system 1000 according to the first embodiment of the present invention executes the first braking mode.

[0124] Reference Figure 2At the initial stage of braking, when the driver depresses the brake pedal 10, the motor (not shown) is operated to rotate in one direction. The motor's rotational force is transmitted to the hydraulic pressure supply unit via the power conversion unit. As the hydraulic piston 1320 of the hydraulic pressure supply unit moves forward, hydraulic pressure is generated in the first pressure chamber 1330. The hydraulic pressure discharged from the first pressure chamber 1330 is transmitted to each wheel cylinder 20 through the hydraulic pressure control device 1400, the first hydraulic circuit 1510, and the second hydraulic circuit 1520 to generate braking force.

[0125] Specifically, the hydraulic pressure of the pressurized medium formed in first pressure chamber 1330 is transmitted to the first through second wheel cylinders in first and second hydraulic circuits 1510, sequentially through first hydraulic flow path 1401 and connecting flow path 1900. At this time, first valve 1411 functions as a check valve, allowing only the flow of pressurized medium discharged from first pressure chamber 1330. This ensures smooth transmission of the hydraulic pressure of the pressurized medium to first through fourth wheel cylinders 21, 22, 23, and 24. Furthermore, the first through fourth inlet valves in the first and second hydraulic circuits remain open, and shutoff valve 1610 remains closed, preventing leakage of the pressurized medium to backup flow path 1600.

[0126] In the first braking mode, the third valve 1413 and the fourth valve 1414 are controlled to be closed to prevent the hydraulic pressure of the pressurized medium formed in the first pressure chamber 1330 from leaking into the second pressure chamber 1340. In addition, the first dump valve 1831 provided in the first bypass flow path 1830 remains closed to prevent the hydraulic pressure formed in the first pressure chamber 1330 from leaking into the reservoir 1100.

[0127] On the other hand, as the oil piston 1320 moves forward, negative pressure is generated in the second pressure chamber 1340, and the hydraulic pressure of the pressurized medium is transferred from the reservoir 1100 to the second pressure chamber 1340 via the second dump flow path 1820, thereby preparing for the second braking mode described later. A second dump check valve 1821 provided in the second dump flow path 1820 allows the pressurized medium to flow from the reservoir 1100 to the second pressure chamber 1340, thereby stably supplying the pressurized medium to the second pressure chamber 1340. Furthermore, the first dump valve 1841 provided in the second bypass flow path 1840 is switched to an open state, thereby quickly supplying the pressurized medium from the reservoir 1100 to the first pressure chamber 1330.

[0128] In the first braking mode in which the wheel cylinder 20 is braked by the hydraulic supply device 1300 , the shutoff valve 1610 provided in the backup flow path 1600 is switched to be closed, thereby preventing the pressurized medium discharged from the integrated master cylinder 1200 from being transmitted to the wheel cylinder 20 side.

[0129] Specifically, while the driver is operating the brake pedal 10, the shutoff valve 1610, located in the backup flow path 1600 (described later), is closed. As the brake pedal 10 continues to be operated, the first master piston 1220 moves forward. However, as the shutoff valve 1610 is closed, the second master chamber 1230a is sealed, preventing the second master piston 1230 from moving forward. When the second master piston 1230 is unable to move forward, the first master piston 1220 continues to move forward, compressing the pedal simulator 1240. This allows the elastic restoring force of the pedal simulator 1240 to be transmitted to the driver as a pedaling feel.

[0130] When a braking pressure higher than that in the first braking mode is required, the electronic braking system 1000 according to the first embodiment of the present invention can be switched from the first braking mode to the Figure 3 Second braking mode shown.

[0131] Figure 3 1 is a diagram showing a hydraulic circuit of the electronic brake system 1000 according to the first embodiment of the present invention in a state where the electronic brake system 1000 performs the second braking mode. Figure 3 When the displacement or operating speed of the brake pedal 10 detected by the pedal displacement sensor is higher than a preset level, or the hydraulic pressure detected by the pressure sensor is higher than a preset level, the electronic control unit determines that a higher braking pressure is required, so that it can switch from the first braking mode to the second braking mode.

[0132] When switching from the first braking mode to the second braking mode, the motor is operated to rotate in the other direction, and the rotational force of the motor is transmitted to the hydraulic pressure supply unit through the power conversion unit, causing the hydraulic piston 1320 to move rearward, thereby generating hydraulic pressure in the second pressure chamber 1340. The hydraulic pressure discharged from the second pressure chamber 1340 is transmitted to each wheel cylinder 20 through the hydraulic control device 1400, the first hydraulic circuit 1510, and the second hydraulic circuit 1520 to generate braking force.

[0133] Specifically, the hydraulic pressure generated in second pressure chamber 1340 passes through second hydraulic flow path 1402 and connecting flow path 1900, and is transmitted a second time to the first through fourth wheel cylinders 21, 22, 23, and 24, located in first and second hydraulic circuits 1510 and 1512. At this time, second valve 1412, located in second hydraulic flow path 1402, serves as a check valve that only allows the flow of pressurized medium discharged from second pressure chamber 1340. This ensures smooth transmission of the hydraulic pressure of the pressurized medium to first through fourth wheel cylinders 21, 22, 23, and 24. First through fourth inlet valves 1511b, located in first and second hydraulic circuits 1510 and 1512b, remain open, and shutoff valve 1610 remains closed, preventing leakage of the hydraulic pressure of the pressurized medium toward backup flow path 1600.

[0134] In the second braking mode, the third valve 1413 and the fourth valve 1414 are controlled to be in the closed state, thereby preventing the hydraulic pressure of the pressurized medium formed in the second pressure chamber 1340 from leaking into the first pressure chamber 1330. In addition, the second dump valve 1841 is switched to the closed state, thereby preventing the hydraulic pressure of the pressurized medium formed in the second pressure chamber 1340 from leaking into the reservoir 1100.

[0135] On the other hand, as the hydraulic piston 1320 moves backward, negative pressure is generated in the first pressure chamber 1330, and the hydraulic pressure of the pressurized medium is transferred from the reservoir 1100 to the first pressure chamber 1330 via the first dump flow path 1810, thereby preparing for the third braking mode, which will be described later. A first dump check valve 1811 provided in the first dump flow path 1810 allows the pressurized medium to flow from the reservoir 1100 to the first pressure chamber 1330, thereby stably supplying the pressurized medium to the first pressure chamber 1330. Furthermore, a first dump valve 1831 provided in the first bypass flow path 1830 is switched to an open state, thereby quickly supplying the pressurized medium from the reservoir 1100 to the first pressure chamber 1330.

[0136] The operation of the integrated master cylinder 1200 in the second braking mode is the same as the operation of the integrated master cylinder 1200 of the above-described electronic brake system in the first braking mode, and thus description will be omitted to avoid duplication of content.

[0137] When a higher braking pressure than the second braking mode is required, the electronic braking system 1000 according to the first embodiment of the present invention can be switched from the second braking mode to the Figure 4 The third braking mode is shown.

[0138] Figure 4 1 is a hydraulic circuit diagram showing a state in which the electronic brake system 1000 according to the first embodiment of the present invention performs the third braking mode. Figure 4 When the displacement or operating speed of the brake pedal 10 detected by the pedal displacement sensor is higher than a preset level or the hydraulic pressure detected by the pressure sensor is higher than a preset level, the electronic control unit determines that a higher braking pressure is required, so that it can switch from the second braking mode to the third braking mode.

[0139] When switching from the second braking mode to the third braking mode, the motor (not shown) is operated to rotate in one direction, and the rotational force of the motor is transmitted to the hydraulic pressure supply unit through the power conversion unit, causing the hydraulic piston 1320 of the hydraulic pressure supply unit to move forward again, thereby generating hydraulic pressure in the first pressure chamber 1330. The hydraulic pressure discharged from the first pressure chamber 1330 is transmitted to each wheel cylinder 20 through the hydraulic pressure control device 3400, the first hydraulic circuit 1510, and the second hydraulic circuit 1520 to generate braking force.

[0140] Specifically, a portion of the hydraulic pressure generated in first pressure chamber 1330 is transmitted sequentially through first hydraulic flow path 1401 and connecting flow path 1900 to the first through fourth wheel cylinders 21, 22, 23, and 24 provided in the first and second hydraulic circuits. At this time, first valve 1411 functions as a check valve, allowing only the flow of pressurized medium discharged from first pressure chamber 1330. This ensures smooth transmission of the hydraulic pressure of the pressurized medium to the first through fourth wheel cylinders 21, 22, 23, and 24. Furthermore, first through fourth inlet valves 1511b provided in first and second hydraulic circuits remain open, and shutoff valve 1610 remains closed, preventing leakage of the pressurized medium's hydraulic pressure toward backup flow path 1600.

[0141] On the other hand, since the third braking mode provides high-pressure hydraulic pressure, as hydraulic piston 1320 moves forward, the hydraulic pressure in first pressure chamber 1330 increases the force that forces hydraulic piston 1320 to move backward, dramatically increasing the load applied to the motor. Therefore, in the third braking mode, third valve 1413 and fourth valve 1414 are opened and operated, allowing pressurized medium to flow through third and fourth hydraulic flow paths 1403 and 1404. In other words, the remaining hydraulic pressure generated in first pressure chamber 1330 is supplied to second pressure chamber 1340 via first and third hydraulic flow paths 1401 and 1403, respectively. This allows the first and second pressure chambers 1330 and 1340 to communicate with each other, synchronizing the hydraulic pressures. This reduces the load applied to the motor and improves the durability and reliability of the device.

[0142] In the third braking mode, the first dump valve 1831 is switched to a closed state, thereby preventing the hydraulic pressure of the pressurized medium formed in the first pressure chamber 1330 from leaking to the reservoir 1100 along the first bypass flow path 1830, and the second dump valve 1841 is also controlled to a closed state, and as the oil hydraulic piston 1320 moves forward, a negative pressure is quickly formed in the second pressure chamber 1340, so that the pressurized medium provided from the first pressure chamber 1330 can be smoothly received.

[0143] In the third braking mode, the operation of the integrated master cylinder 1200 is the same as that of the integrated master cylinder 1200 of the above-described electronic brake system in the first and second braking modes, and thus description will be omitted to avoid duplication of content.

[0144] Hereinafter, the state in which the electronic brake system 1000 according to the first embodiment of the present invention cannot operate normally, ie, the operating state in the fall-back mode, will be described.

[0145] Figure 5 This is a hydraulic circuit diagram showing an operating state in an abnormal operating mode (reverse mode) when the electronic brake system 1000 according to the first embodiment of the present invention cannot operate normally due to a device failure or the like.

[0146] Reference Figure 5 In the non-normal operating mode, each valve is controlled to an initial braking state, representing a non-operating state. At this point, when the driver applies a pedal force to brake pedal 10, first and second master pistons 1220 and 1230, connected to brake pedal 10, move forward and undergo displacement. In the non-operating state, shutoff valve 1610 is set to an open state. Therefore, as the second master piston moves forward, the pressurized medium contained in the second master chamber is transferred via backup flow path 1600 and connecting flow path 1900 to the first through fourth wheel cylinders 21, 22, 23, and 24 of the first and second hydraulic circuits, thereby achieving braking.

[0147] Hereinafter, an electronic brake system 2000 according to a second embodiment of the present invention will be described.

[0148] Figure 6 2 is a hydraulic circuit diagram showing an electronic brake system 2000 according to a second embodiment of the present invention. Figure 6 Unlike the first embodiment, the electronic brake system 2000 according to the second embodiment omits the second reservoir flow path 1720 communicating the reservoir 1100 and the first master chamber, and omits the first sealing member 1290a sealing the first master chamber 1220a from the outside.

[0149] The description of the electronic brake system 2000 according to the second embodiment of the present invention described below is the same as the description of the electronic brake system 1000 according to the first embodiment of the present invention described above, except for the use of additional figure marks, and therefore the description is omitted to avoid duplication of content.

[0150] The electronic brake system of the first embodiment of the present invention can accommodate a pressurized medium within the first master chamber 1220a, thereby enabling wet operation. However, the electronic brake system of the second embodiment can be configured to operate in a dry mode, without accommodating a pressurized medium within the first master chamber 2220a. Therefore, compared to the first embodiment, the electronic brake system of the second embodiment can omit components such as the second reservoir flow path 1720 and the first sealing member 1290a, thereby achieving braking with a simpler structure and operation, and contributing to cost reduction.

[0151] As described above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited thereto, and a person skilled in the art may make various modifications and variations within the technical concept of the present invention and the equivalent scope of the following claims.

Claims

1. An electronic braking system, characterized in that: include: Reservoirs, storing pressurized media, The integrated master cylinder includes a master piston connected to the brake pedal, a master chamber whose volume can be changed according to the displacement of the master piston, and a pedal simulator connected to the master piston to provide a pedaling feel. A hydraulic pressure supply device operates a hydraulic piston to generate hydraulic pressure according to an electrical signal outputted corresponding to the displacement of the brake pedal. The first hydraulic circuit controls the flow of pressurized medium supplied to the first wheel cylinder and the second wheel cylinder. The second hydraulic circuit controls the flow of pressurized medium supplied to the third and fourth wheel cylinders. A single backup flow path, one end of which is connected to the main chamber, and the other end of which is connected to either the first hydraulic circuit or the second hydraulic circuit. a stop valve provided in the backup flow path to control the flow of the pressurized medium, and a connecting flow path connecting the first hydraulic circuit and the second hydraulic circuit; The connecting flow path and the other end of the backup flow path communicate with each other.

2. The electronic braking system according to claim 1, characterized in that: The connecting flow path and the other end of the backup flow path are directly communicated with each other without a valve provided therebetween.

3. The electronic braking system according to claim 2, characterized in that: The integrated master cylinder comprises: The first master piston is connected to the brake pedal. The second master piston is configured to be displaceable according to the displacement of the first master piston, a first master chamber, the volume of which can be changed according to the displacement of the first master piston, and a second master chamber, the volume of which can be changed according to the displacement of the second master piston; One end of the backup flow path is connected to the second main chamber.

4. The electronic braking system according to claim 3, characterized in that: The pedal simulator is disposed between the first master piston and the second master piston.

5. The electronic braking system according to claim 2, characterized in that: Also includes: an oil pressure control device, disposed between the hydraulic supply device and the first and second oil pressure circuits to regulate the flow of a pressurized medium; The first hydraulic circuit and the second hydraulic circuit each include at least one inlet valve for controlling the flow of pressurized medium delivered to at least one of the first to fourth wheel cylinders. The connecting flow path is provided between a rear end of the oil pressure control device and a front end of the inlet valve.

6. The electronic braking system according to claim 5, characterized in that: The hydraulic supply device includes a first pressure chamber provided in front of the oil pressure piston and a second pressure chamber provided behind the oil pressure piston. The oil pressure control device includes: a first hydraulic flow path connecting the first pressure chamber and the connecting flow path; a second hydraulic flow path connecting the second pressure chamber and the connecting flow path; A third hydraulic flow path has one end connected to the first hydraulic flow path and the other end connected to the second hydraulic flow path. The fourth hydraulic flow path connects the third hydraulic flow path and the connecting flow path.

7. The electronic braking system according to claim 6, characterized in that: The oil pressure control device includes: a first valve, provided in the first hydraulic flow path to control the flow of the pressurized medium; A second valve is provided in the second hydraulic flow path to control the flow of the pressurized medium. a third valve provided in the third hydraulic flow path and between one end of the third hydraulic flow path and a connection portion between the third hydraulic flow path and the fourth hydraulic flow path; and The fourth valve is provided in the third hydraulic flow path and is provided between the other end of the third hydraulic flow path and a connection point between the third hydraulic flow path and the fourth hydraulic flow path.

8. The electronic braking system according to claim 7, characterized in that: The first valve is configured as a check valve that only allows the flow of pressurized medium discharged from the first pressure chamber. The second valve is configured as a check valve that only allows the flow of the pressurized medium discharged from the second pressure chamber. The third valve and the fourth valve are configured as solenoid valves for controlling bidirectional flow of the pressurized medium.

9. The electronic braking system according to claim 3, characterized in that: Also includes: The first reservoir flow path connects the reservoir and the second main chamber.

10. The electronic brake system according to claim 3, characterized in that: The first main chamber is configured as a dry type that does not contain a pressurized medium.

11. The electronic braking system according to claim 9, characterized in that: Also includes: The second reservoir flow path connects the reservoir and the first main chamber.

12. The electronic brake system according to claim 1, characterized in that Also includes: The detection sensor detects a liquid level of the pressurized medium contained in the reservoir.

13. The electronic brake system according to claim 6, characterized in that: Also includes: A dump control unit is provided between the reservoir and the hydraulic supply device to control the flow of the pressurized medium.

14. The electronic brake system according to claim 13, characterized in that: The dump control unit includes: a first dump control unit that controls the flow of the pressurized medium between the first pressure chamber and the reservoir, The second dump control unit controls the flow of the pressurized medium between the second pressure chamber and the reservoir.

15. The electronic brake system according to claim 14, characterized in that: The first dump control unit includes: a first dump flow path connecting the first pressure chamber and the reservoir, a first bypass flow path that branches off from the first dump flow path and then rejoins; The second dump control unit includes: a second dump flow path connecting the second pressure chamber and the reservoir, The second bypass flow path branches off from the second dump flow path and then rejoins.

16. A method for operating an electronic brake system, wherein the electronic brake system is the electronic brake system according to claim 7, characterized in that: The normal operation mode gradually increases the hydraulic pressure of the pressurized medium transmitted from the hydraulic pressure supply device to the first to fourth wheel cylinders, including: In the first braking mode, hydraulic pressure is supplied for the first time. Second braking mode, providing hydraulic pressure a second time, and In the third braking mode, hydraulic pressure is supplied for the third time.

17. The method for operating an electronic brake system according to claim 16, characterized in that: In the first braking mode, the pressurized medium contained in the first pressure chamber is transferred to the first to fourth wheel cylinders by the forward movement of the oil piston.

18. The method for operating an electronic brake system according to claim 17, wherein: In the second braking mode, the pressurized medium contained in the second pressure chamber is transferred to the first to fourth wheel cylinders by the rearward movement of the oil piston.

19. The method for operating an electronic brake system according to claim 18, wherein: In the third braking mode, the third valve and the fourth valve are opened, and the oil piston moves forward again to transfer a portion of the pressurized medium of the first pressure chamber to the first to fourth wheel cylinders, and the remaining pressurized medium of the first pressure chamber to the second pressure chamber.

20. The method for operating an electronic brake system according to claim 16, wherein: Also includes: a fallback mode, which is switched when the brake of the hydraulic supply device fails; In the fallback mode, the pressurized medium exhausted from the integrated master cylinder passes through the backup flow path and the connecting flow path and is entirely delivered to the first to fourth wheel cylinders.

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