The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 21, 2015
Filed:
Sep. 22, 2011
Yukihiko Yamada, Minami-ALPS, JP;
Kentaro Ueno, Minami-ALPS, JP;
Yusuke Nozawa, Minami-ALPS, JP;
Daisuke Kojima, Minami-ALPS, JP;
Tohma Yamaguchi, Minami-ALPS, JP;
Yukihiko Yamada, Minami-ALPS, JP;
Kentaro Ueno, Minami-ALPS, JP;
Yusuke Nozawa, Minami-ALPS, JP;
Daisuke Kojima, Minami-ALPS, JP;
Tohma Yamaguchi, Minami-ALPS, JP;
Hitachi Automotive Systems, Ltd., Ibaraki, JP;
Abstract
An electric motor is controlled based on an operation of a brake pedal to move a primary piston forward through a ball screw mechanism, thereby generating a hydraulic pressure in a master cylinder. At this time, a reaction force from the hydraulic pressure in the master cylinder is fed back to the brake pedal through an input piston. Automatic brake control, which generates the hydraulic pressure by driving the electric motor regardless of whether there is the operation of the brake pedal, is carried out. During the automatic brake control, an actual relative position is compared with a determination threshold value set based on the relative position between the primary piston and the input piston which is generated by a movement of the primary piston, and it is determined that the brake pedal is operated in a case where the relative position is smaller than the determination threshold value.