Brake control apparatus and control method thereof
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsMasayasu Ohkubo, Akihiro Otomo, Tsukasa Fukasawa
Life of this patent
Estimating the term…
Abstract
A brake control apparatus has first and second wheel cylinders; a master cylinder unit; first and second systems; a separation valve; a pressure control mechanism that controls the working fluid pressure transferred to at least one of the first and second wheel cylinders independently of the brake operation, and a brake ECU. The brake ECU generates a differential pressure across the separation valve by operating the pressure control mechanism when there is no brake operation while a running drive source of a vehicle is stopped to determine whether the separation valve has a leakage abnormality.
Claims15
A brake control apparatus comprising:
- a first wheel cylinder that applies braking force to a first wheel;
- a second wheel cylinder that applies the braking force to a second wheel that is different from the first wheel;
- a manual hydraulic pressure source that pressurizes a working fluid in accordance with an amount of operation of a brake operating member;
- a first system that communicably connects the manual hydraulic pressure source and the first wheel cylinder, and that transfers working fluid pressure in the manual hydraulic pressure source to the first wheel cylinder;
- a second system that communicably connects the manual hydraulic pressure source and the second wheel cylinder, and that transfers the working fluid pressure in the manual hydraulic pressure source to the second wheel cylinder;
- a main channel that communicably connects the first system and the second system;
- a separation valve provided in the main channel;
- a pressure control mechanism that controls the working fluid pressure transferred to at least one of the first wheel cylinder and the second wheel cylinder independently of the amount of operation of the brake operating member;
- and
- a control device that, when the brake operating member is not operated and the separation valve is closed while a running drive source of a vehicle is stopped, actuates the pressure control mechanism and determines whether the separation valve has an abnormality based on a change in pressure difference between an upstream side and a downstream side of the separation valve.
A brake control method comprising:
- closing a separation valve, provided in a main channel communicably connecting a first system, which transfers working fluid pressure from a manual hydraulic pressure source that pressurizes a working fluid, in accordance with an amount of operation of a brake operating member, to a first wheel cylinder provided for applying braking force to a first wheel, and a second system, which transfers the working fluid pressure from the manual hydraulic pressure source to a second wheel cylinder provided for applying the braking force to a second wheel;
- operating a pressure control mechanism when the brake operating member is not operated while a running drive source of a vehicle is stopped;
- and
- determining whether the separation valve has an abnormality based on a change in pressure difference between an upstream side and a downstream side of the separation valve.
Dependencies are inferred from the claim text.