Patent ID: 9701288
Date: 2017-07-11
CPC Classifications: B60T,F15B

Claim:
1. A hydraulic brake system for braking a vehicle, comprising: a high-pressure-source device configured to supply a working fluid that is highly pressurized; an electromagnetic pressure-increase linear valve and an electromagnetic pressure-decrease linear valve configured to adjust a pressure of the working fluid supplied from the high-pressure-source device to an adjusted pressure; a brake device provided in a wheel and configured to receive the working fluid having the adjusted pressure or a pressure in accordance with the adjusted pressure and to generate a braking force having a magnitude in accordance with the pressure of the received working fluid; a braking-force index detector configured to detect a braking-force index indicative of the braking force; and a controller configured to control the braking force generated by the brake device by controlling an energizing current supplied to each of the pressure-increase linear valve and the pressure-decrease linear valve, wherein the controller is configured to selectively execute one of: (a) a feedback control in which a feedback component that is a component of the energizing current supplied to each of the pressure-increase linear valve and the pressure-decrease linear valve is determined based on a difference between an actual braking-force index detected by the braking-force index detector and a target braking-force index that is a target of the braking-force index in a control, so as to lessen the difference and in which the energizing current that contains the feedback component is supplied to each of the pressure-increase linear valve and the pressure-decrease linear valve; and (b) a feedforward control in which a feedforward component that is a component of the energizing current supplied to each of the pressure-increase linear valve and the pressure-decrease linear valve is determined based on the target braking-force index, without determining the difference between the actual braking-force index detected by the braking-force index detector and the target braking-force index, so as to place each of the pressure-increase linear valve and the pressure-decrease linear valve in a valve equilibrium state that is a boundary between a valve open state and a valve closed state and in which the energizing current that contains the feedforward component is supplied to each of the pressure-increase linear valve and the pressure-decrease linear valve, and wherein the controller is configured to determine, when the feedforward control is executed, the energizing current supplied to at least one of the pressure-increase linear valve and the pressure-decrease linear valve so as to cause the braking force to be larger than the braking force caused when the energizing current is determined in an instance in which the feedforward component is set according to a preset relationship between the braking-force index and the energizing current in the valve equilibrium state.