Braking force control system

Patent metadata

Field	Value
Publication number	US-2016264111-A1
Application number	US-201415034272-A
Country	US
Kind code	A1
Filing date	Nov 7, 2014
Priority date	Nov 8, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

Motor-generators are arranged both at front and rear wheels so as to be capable of using all of four wheels for regeneration. The horizontal axis indicates deceleration of a vehicle, and the vertical axis indicates braking forces for the front and rear wheels, respectively above and below the horizontal axis. A setting value indicates a limit braking force for the rear wheels to be locked. A frictional braking force and a regenerative braking force at the rear wheels are controlled so that the total braking force for the rear wheels does not exceed the setting value.

First claim

1 . A braking force control system comprising:
a regenerative braking force controller that controls a regenerative braking force for rear wheels of a vehicle, which is generated by a first motor-generator for driving the rear wheels; a frictional braking force controller that controls a frictional braking force to be generated by the rear wheels of the vehicle; and a braking force determiner that determines the frictional braking force and the regenerative braking force inclusive of a braking force equivalent to an engine brake, so that a total braking force to be applied to the rear wheels does not exceed a preset value.

2 . The braking force control system according to claim 1 ,
wherein the braking force determiner sets the preset value based on an ideal braking force distribution to the rear wheels, with which the rear wheels are not locked.

3 . The braking force control system according to claim 1 ,
wherein the braking force determiner sets the preset value so as to be smaller than a limit value of the braking force for front wheels of the vehicle to be locked.

4 . The braking force control system according to claim 3 ,
wherein the regenerative braking force controller also controls the regenerative braking force for the front wheels to be generated by a second motor-generator for driving the front wheels of the vehicle; the frictional braking force controller also controls the frictional braking force to be generated by the front wheels of the vehicle; and the braking force determiner sets in advance distributions to the frictional braking forces of the frictional braking force to be generated by the front wheels and the frictional braking force to be generated by the rear wheels, and, on the condition that a deceleration of the vehicle is within a predetermined range, makes the distribution of the frictional braking force to be generated by the rear wheels, in accordance with the preset distribution, smaller than the limit value for the rear wheels to be locked, and makes the distribution of the frictional braking force to be generated by the front wheels larger than a limit value for the front wheels to be locked.

5 . The braking force control system according to claim 1 ,
wherein the regenerative braking force controller also controls the regenerative braking force for the front wheels to be generated by the second motor-generator for driving the front wheels of the vehicle; and the frictional braking force controller also controls the frictional braking force to be generated by the front wheels of the vehicle, includes a slip state detector for detecting that the vehicle is slipping, and, on the condition that the slip state detector detects the vehicle for which the regenerative braking force is being generated is slipping, reduces at a predetermined ratio the regenerative braking force being applied to the front wheels and the regenerative braking force being applied to the rear wheels.

6 . The braking force control system according to claim 5 ,
wherein the predetermined ratio is the ideal distribution ratio for distributing the frictional braking force to the front and rear wheels.

7 . The braking force control system according to claim 5 ,
wherein the predetermined ratio is set so that the sum of the frictional braking force and regenerative braking force to be applied to the rear wheels does not exceed a limit braking force for the rear wheels to be locked.

8 . The braking force control system according to claim 1 , further comprising:
an ABS controller that executes antilock brake control for reducing the frictional braking force upon detecting that the vehicle is slipping, wherein the slip state detector detects that the vehicle is slipping, to reduce the regenerative braking forces to be applied to the front and rear wheels, with a variation in a vehicle condition which is smaller than that of the ABS controller detecting that the vehicle is slipping.

9 . The braking force control system according to claim 1 ,
wherein if an accelerator pedal is stepped for operation at a time of the slip state detector detecting that the vehicle is slipping, a traveling mode is switched to one in which the front and rear wheels are driven by the first and second motor-generators, respectively.

Assignees

• Honda Motor Co Ltd

Inventors

• Doi Shigeru
• Shimoda Akio
• Yanagida Hisanori

Classifications

• B60T8/267

  for hybrid systems with different kind of brakes on different axles · CPC title

• B60T8/4081

  Systems with stroke simulating devices for driver input (B60T8/4077 takes precedence) · CPC title

• B60T2270/602

  ABS features related thereto · CPC title

• B60T8/1766 Primary

  Proportioning of brake forces according to vehicle axle loads, e.g. front to rear of vehicle · CPC title

• B60T2270/604

  Merging friction therewith; Adjusting their repartition · CPC title