DE-102021109506-B4 - Electro-hydraulic braking system

Abstract

Electro-hydraulic braking system with: several wheel brake arrangements designed to deliver braking forces to wheels; an electric brake booster with a motor to amplify a pedal force applied to a brake pedal; an electronic stability control (ESC) system comprising a pressure sensor for measuring hydraulic pressure and designed to open or close several valves arranged therein in order to distribute the hydraulic pressure to the multiple wheel brake assemblies; and an electronic control unit (ECU) designed to control a motor drive current within a range of current values less than or equal to a first limiting current when the hydraulic pressure measured by the pressure sensor is less than or equal to a first reference value, and to control the motor drive current within a range of current values greater than the first limiting current and less than or equal to a second limiting current when the hydraulic pressure is higher than the first reference value.

Inventors

• Ha Min JUNG

Assignees

• HYUNDAI MOBIS CO., LTD.

Dates

Publication Date

20260513

Application Date

20210415

Priority Date

20200417

Claims (9)

1. Electro-hydraulic braking device comprising: multiple wheel brake assemblies configured to deliver braking forces to wheels; an electric brake booster with a motor for amplifying a pedal force applied to a brake pedal; an electronic stability control (ESC) system comprising a pressure sensor for measuring hydraulic pressure and configured to open or close multiple valves arranged therein to distribute the hydraulic pressure to the multiple wheel brake assemblies; and an electronic control unit (ECU) configured to control a drive current of the motor within a range of current values less than or equal to a first limiting current when the hydraulic pressure measured by the pressure sensor is less than or equal to a first reference value, and to control the drive current of the motor within a range of current values greater than the first limiting current and less than or equal to a second limiting current when the hydraulic pressure is greater than the first reference value.
2. Electro-hydraulic braking system according to Claim 1 , in which the sensor contained in the ESC system is designed as multiple sensors.
3. Electro-hydraulic braking system according to Claim 2 , in which the ECU controls the motor's drive current according to an average value of values measured by the multiple pressure sensors.
4. Electro-hydraulic braking system according to Claim 1 , in which the ESC system has an X-shaped split structure.
5. Electro-hydraulic braking system according to Claim 1 , in which the ESC system further comprises: a traction control valve designed to interrupt hydraulic pressure supplied by a master brake cylinder when the brake pedal is actuated; an inlet valve designed to interrupt hydraulic pressure supplied to multiple wheel brakes; an actuator designed to supply hydraulic pressure to the multiple wheel brakes; and a high-pressure switching valve designed to interrupt hydraulic pressure supplied by the master brake cylinder.
6. Electro-hydraulic braking system according to Claim 1 , in which the ESC system further includes an outlet valve designed to adjust the hydraulic pressure supplied to the multiple wheel brake arrangements.
7. A method for controlling an electro-hydraulic brake, comprising the following steps: Measuring a hydraulic pressure value by a pressure sensor provided in an electronic stability control (ESC) system; Transmitting the hydraulic pressure value to an electronic control unit (ECU); and Controlling a drive motor within a range of current values less than or equal to a first limiting current when the hydraulic pressure measured by the pressure sensor is less than or equal to a first reference value, and controlling the drive current of the motor within a range of current values greater than the first limiting current and less than or equal to a second limiting current when the hydraulic pressure is higher than the first reference value.
8. Procedure according to Claim 7 , in which measuring a hydraulic pressure value involves measuring the hydraulic pressure in the ESC system with an X-shaped divided structure.
9. Procedure according to Claim 7 , in which measuring a hydraulic pressure value involves obtaining an average of hydraulic pressure values measured by several pressure sensors.

Description

Technical field The present invention relates to an electro-hydraulic brake unit. background The statements in this section merely provide background information regarding the present disclosure and do not necessarily represent prior art. A braking system comprises a reservoir, one or more lines, and multiple wheel brake assemblies. Brake fluid dispensed from the reservoir flows through the one or more lines to the multiple wheel brakes. This electro-hydraulic braking system applies braking force to the vehicle's brakes using the pedal force of a driver. However, with such a conventional electro-hydraulic brake, when the driver presses a pedal, the amplification limit of an electric brake booster motor is constantly set, regardless of the magnitude of the required force. This means that, since the motor's amplification limit is equal to its maximum value, the motor's rated point is set high based on this maximum amplification limit, even when the required braking force is low. Therefore, a motor with a high torque specification should be used if the motor's rated point is set high. This, however, presents disadvantages regarding the motor's cost-effectiveness. DE 11 2018 006 055 T5 Disclosing an electro-hydraulic braking device with multiple wheel brake assemblies configured to deliver braking forces to wheels; an electric brake booster with a motor for amplifying a pedal force applied to a brake pedal; an electronic stability control system comprising a pressure sensor for measuring hydraulic pressure and configured to open or close multiple valves arranged therein to distribute the hydraulic pressure to the multiple wheel brake assemblies; and an electronic control unit configured to limit a drive current of the motor when a condition for limiting the drive of the electric actuator is met. overview According to at least one embodiment, the present disclosure provides an electro-hydraulic braking device comprising: several wheel brake assemblies configured to deliver braking forces to wheels; an electric brake booster with a motor for amplifying a pedal force applied to a brake pedal; an electronic stability control (ESC) system comprising a pressure sensor for measuring hydraulic pressure and configured to open or close several valves arranged therein in order to distribute the hydraulic pressure to the several wheel brake assemblies; and an electronic control unit (ECU) configured to control a drive current of the motor within a range of current values less than or equal to a first limiting current when the hydraulic pressure measured by the pressure sensor is less than or equal to a first reference value, and to control the drive current of the motor within a range of current values greater than the first limiting current and less than or equal to a second limiting current when the hydraulic pressure is higher than the first reference value. Brief description of the drawings 1 is a block diagram of an electro-hydraulic braking device according to an embodiment of the present invention.2 is a block diagram of an electronic stability control system according to an embodiment of the present invention.3 is a graph of input/output characteristics according to an embodiment of the present invention.4 is a graph of a TNI curve of an engine according to an embodiment of the present invention. Reference symbol list 110Main body120electric brake booster130electronic control unit150Wheels200Hydraulic control systemFL, RR, RL and FRWheel brakes Detailed description According to one embodiment of the present invention, an intermediate amplification point is set for low-response braking, and a motor rating point is set based on this. This means that the motor rating point is set lower than that of a conventional motor. Because the motor rating point is set lower, the required motor power decreases. The present invention relates to the creation of an electric brake booster in which the size of the motor is reduced, and thus, due to the reduced motor power, the price of the motor is reduced, thereby lowering the manufacturing costs of the electric brake booster. Some exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings. In the following description, identical reference numerals preferably denote identical elements, even though the elements are shown in different drawings. Furthermore, for the sake of clarity and brevity, a detailed description of known functions and configurations included in some embodiments is omitted in the following description. Furthermore, alphanumeric codes such as first, second, i), ii), (a), (b), etc., are used in the numbering of components solely to distinguish one component from another, and not to imply or suggest the content, order, or sequence of the components. If a part is described as "containing" or "having" a component, this is to be understood throughout the description as meaning that the part may also have other component