Patent ID: 7798576
Filing Date: 2010-09-21
Classification: B60T

Abstract:
1. A brake control device for a vehicle, comprising: a brake operating member to be operated by a driver; an operation amount sensor for detecting an operation amount of the brake operating member; a first and a second front wheel cylinder, which are respectively installed to two front wheels; a first and a second rear wheel cylinder, which are respectively installed to two rear wheels; a reservoir for storing brake fluid; a main conduit for connecting the first and second front wheel cylinders and the first and second rear wheel cylinders with the reservoir, the main conduit branching into four sections which are respectively connected with the first and second front wheel cylinders and the first and second rear wheel cylinders; a first pump located in a first one of the four sections, the first pump for pressurizing a first one of the first front wheel cylinder, the second front wheel cylinder, the first rear wheel cylinder, and the second rear wheel cylinder by drawing in and discharging the brake fluid stored in the reservoir; a second pump located in a second one of the four sections, the second pump for pressurizing a second one of the first front wheel cylinder, the second front wheel cylinder, the first rear wheel cylinder, and the second rear wheel cylinder by drawing in and discharging the brake fluid stored in the reservoir; a third pump located in a third one of the four sections, the third pump for pressurizing a third one of the first front wheel cylinder, the second front wheel cylinder, the first rear wheel cylinder, and the second rear wheel cylinder by drawing in and discharging the brake fluid stored in the reservoir; a fourth pump located in a fourth one of the four sections, the fourth pump for pressurizing a fourth one of the first front wheel cylinder, the second front wheel cylinder, the first rear wheel cylinder, and the second rear wheel cylinder by drawing in and discharging the brake fluid stored in the reservoir; a first electrical motor for driving the first and second pumps which are provided to a first conduit system of the main conduit and pressurize the first conduit system; a second electrical motor for driving the third and fourth pumps which are provided to a second conduit system of the main conduit and pressurize the second conduit system; first to fourth adjustment conduits, which are located respectively in parallel with the first to fourth pumps and return the brake fluid to the reservoir; first to fourth linear valves, which are respectively located in the first to fourth adjustment conduits; and a control means for controlling, based on a detection signal from the operation amount sensor, the first to fourth linear valves, the first electrical motor, and the second electrical motor, wherein the control means includes: a first calculating portion for calculating target wheel cylinder pressures corresponding to the operation amount detected by the operation amount sensor when the operation amount sensor detects that the brake operating member is operated; a second calculating portion for calculating slip ratios of the front wheels and the rear wheels; an ABS control portion for executing an ABS control based on the slip ratios calculated by the second calculating portion; a friction estimating portion for estimating friction coefficients of sections of a road on which the front wheels and the rear wheels are located, respectively; a motor control portion for: wherein the motor control portion: