Vehicle brake mechanism and method for controlling the vehicle brake mechanism

Abstract

A vehicle brake mechanism and a method for controlling the vehicle brake mechanism. In a BBW brake mechanism, a driven cylinder having a single hydraulic with a simple structure is employed so as to realize the standby when one system in two brake systems is failed. A master cut valve 32 is closed and a connection control valve 41 is opened to make first and second liquid paths Pb, Qb connect with the driven cylinder 42, thereby simplifying the structure without a serial driven cylinder. When the power supply is failed, the master cut valve 32 is opened and the connection control valve 41 is closed. The brake hydraulic pressure generated by the first and second hydraulic chambers of the master cylinder 11 respectively drives the wheel cylinders 26, 27, 30, and 31 of the first and second systems to act. Herein, the brake force is guaranteed through the action of the other system even if one system in the first and second systems generates the liquid leakage defect because the first and second liquid paths Pb, Qb are separated.

Description

technical field [0001] The present invention relates to a so-called BBW (full circuit brake) system that converts the operation of the brake pedal by the driver into an electric signal, and uses the brake hydraulic pressure generated by the slave cylinder controlled based on the electric signal to activate the wheel cylinder. A braking device for a vehicle and a control method thereof. Background technique [0002] According to the following patent document 1, it is known that such a BBW-type vehicle brake device includes a tandem master cylinder, a tandem slave cylinder, a first system wheel cylinder, and a second system wheel cylinder, so that the master cylinder The first hydraulic chamber of the cylinder is connected with the wheel cylinder of the first system via the first hydraulic chamber of the slave cylinder, and the second hydraulic chamber of the master cylinder is connected with the wheel cylinder of the second system via the second hydraulic chamber of the slave...

AI Technical Summary

Problems solved by technology

[0004] However, in the above-mentioned conventional device, the slave cylinder needs to have the first and second hydraulic chambers corresponding to the wheel cylinders of the first system and the wheel cylinder of the second system, so there is a problem that the structure of the slave cylinder is complicated.

In order to solve this problem, when the brake hydraulic pressure is supplied from the slave cylinder with a single hydraulic chamber to the wheel cylinders of the first and second systems, the brake hydraulic pressure generated by the master cylinder will operate the wheel cylinders when the slave cylinder fails. If there is a defect such as fluid leakage in the wheel cylinder of one of the first and second systems, there is a possibility that the braking force of the wheel cylinders of both the first and second systems will be lost.

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