US 7,621,603 B2 · Vehicle brake control device

Abstract

When the ABS control is executed by the ABS control portion, the vehicle brake control device calculates the first rotational speeds of the first and second motors necessary to achieve the corresponding pressure increase rates and calculates the second rotational speeds of the first and second motors as the upper limits caused by the unlocking pressure limits. Then the vehicle brake control device controls current values of the currents to be supplied to the first and second motors so that they are rotated in the rotational speeds obtained within a range from the first rotational speeds to the second rotational speeds.

A vehicle brake control device, 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 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 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
control means for controlling, based on a detection signal from the operation amount sensor, the first to fourth linear valves, the first motor, and the second 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 third calculating portion for calculating pressure increase rates of the wheel cylinder pressures based on the target wheel cylinder pressures calculated by the first calculating portion;
a fourth calculating portion for estimating friction coefficients of sections of the road on which the front wheels and the rear wheels are located, respectively;
a fifth calculation portion for calculating unlocking pressure limits for the front wheel cylinders and the rear wheel cylinders based on the estimated friction coefficients;
a sixth calculation portion for calculating target rotational speeds of the first and second motors so that the target rotational speed of the first motor is within a range from first one of first rotational speeds to first one of second rotational speeds and the target rotational speed of the second motor is within a range from second one of the first rotational speeds to second one of the second rotational speeds, wherein the first rotational speeds correspond respectively to the pressure increase rates calculated by the third calculating portion and the second rotational speeds correspond respectively to the unlocking pressure limits calculated by the fifth calculation portion;
and
an adjusting portion for adjusting current values of currents to be supplied to the first and second motors based on the target rotational speeds of the first and second motors calculated by the sixth calculation portion.

23 more elements

Description12,166 words

Summary1,969 words

#This application is based on and incorporates herein by reference Japanese patent applications No. 2006-59421 filed on Mar. 6, 2006 and No. 2006-286614 filed on Oct. 20, 2006.

#The present invention relates to a vehicle brake control device which generates pressures (hereinafter referred to as W/C pressures) in wheel cylinders (hereinafter referred to as W/Cs) by causing pumps to apply pressures.

#In Japanese Patent Publication No. H10-203338, a brake-by-wire vehicle brake control device is proposed which has four pumps respectively for the four wheels of a vehicle. Two of the four pumps are located in a common conduit system for two of the four wheels and are driven by a common motor. The other two of the four pumps are located in another common conduit system for the other two of the four wheels and are driven by another common motor.

Brief description of the drawings14 figures

#The invention, together with additional objective, features and advantages thereof, will be best understood from the following description, the appended claims and the accompanying drawings. In the drawings:

#FIG. 1 is a diagram showing a hydraulic circuit configuration of a vehicle brake control device according to a first embodiment of the present invention;

#FIG. 2 is a block diagram showing input-output relationships of signals of a brake ECU that controls a control system of the vehicle brake control device shown in FIG. 1;

Detailed description9,838 words

#Embodiments of the present invention will be described below with reference to the drawings. In the embodiments below, identical reference symbols are used in the drawings to represent identical or equivalent elements.

#A vehicle brake control device according to a first embodiment of the present invention is applied to a vehicle with an X-shaped hydraulic circuit including two conduit systems, one of which serves the right front wheel and the left rear wheel and the other of which serves the left front wheel and the right rear wheel.

#As shown in FIG. 1, the vehicle brake control device includes a brake pedal 1, a depression force sensor 2, a master cylinder (hereinafter referred to as an M/C) 3, a stroke control valve SCSS, a stroke simulator 4, a brake fluid pressure control actuator 5, and wheel cylinders (hereinafter referred to as W/Cs) 6FL, 6FR, 6RL, 6RR, as well as a brake ECU 100 shown in FIG. 2.

Facts

Application

11/709,092Filed 22 Feb 2007

Priority

JP 2006-0594216 Mar 2006

Published

US 2007/0205658 A16 Sep 2007

Granted

24 Nov 2009

Term ends

18 May 2028

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 451 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification4 codes

B60T 7/042
Foot actuated: by electrical means, e.g. using travel or force sensors
B60T 8/4059
Control of the pump unit: involving the rate of delivery
B60T 8/4081
Systems in which a driver input signal is used as a control signal for the additional fluid circuit which is normally used for braking: systems…
B60T
Vehicle brake control systems or parts thereof

Timeline

6 Mar 2006Priority claimedJP 2006-059421
22 Feb 2007Application filedUS 11/709,092
22 Feb 2007Assigned to Advics Co., Ltd.assignment of assignor's interest
6 Sep 2007PublishedUS 2007/0205658 A1
24 Nov 2009GrantedUS 7,621,603 B2
12 Oct 2026TodayWithin its term
18 May 2028Term endsEstimated, includes 451 days of adjustment

Vehicle brake control device

Life of this patent

Vehicle brake control device

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims7

Description12,166 words

Drawings

Classification4 codes

Life of this patent

Description12,166 words