Hitachi Automotive Systems, Ltd.

Tatsuji Ohkubo

Daisuke Goto

Toshiyuki Innami

Kentaro Ueno

Tohma Yamaguchi

Masayuki Kikawa

Makoto Matsuura

An ECU () outputs control signals to an electric booster () of a fluid-pressure generating device () and to an ESC (). In this way, the establishment and cutting off of communication through pressure-increase control valves (), ('), (), and (&#x2032;) of the ESC () are controlled to connect each of wheel cylinders () to () in turn to the master cylinder (). In doing so, the electric booster () is controlled for each of the wheel cylinders () to () to measure a stroke of a piston (), () of a master cylinder (), or a volume of brake fluid proportional to the stroke of the piston (), (), and a fluid pressure detected by fluid-pressure sensors () and (). The fluid volume-pressure characteristic of each of the wheel cylinders () to () so determined is used for comparison to detect any atmospheric air in each pipeline.

Brake apparatus and method for detecting air in pipelines of the brake apparatus

A second ECU determines whether or not there is an abnormality in a hydraulic-pressure sensor in a first cycle based on a detection value of the hydraulic-pressure sensor, and outputs a signal indicating a determination of an occurrence of the abnormality to a first ECU via a signal line when determining the occurrence of the abnormality in the hydraulic-pressure sensor. The first ECU receives the detection value of the hydraulic-pressure sensor through communication from the second ECU via the signal line to determine whether or not there is the abnormality in the hydraulic-pressure sensor in a second cycle that is shorter than the first cycle. When determining that the hydraulic-pressure sensor is abnormal, the first ECU controls driving of an electric actuator based on a braking command from an operation-amount detection sensor without using the detection value of the hydraulic-pressure sensor determined to be abnormal.

Vehicle control apparatus and brake control apparatus

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Maebashi, Japan

Tatsuji Ohkubo