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:
Nov. 27, 2007
Filed:
Feb. 13, 2004
Tohma Yamaguchi, Tokyo-to, JP;
Takeshi Yamamura, Iwata, JP;
Tohma Yamaguchi, Tokyo-to, JP;
Takeshi Yamamura, Iwata, JP;
Kabushiki Kaisha Hitachi Seisakusho, Tokyo, JP;
Abstract
An object of the present invention is to provide an electric disc brake apparatus having a simple constitution in which the operating condition of a parking brake can be reliably detected. A controller detects the operating condition (steps S, S) of a solenoid for driving a parking brake locking mechanism (holding mechanism) by means of a motor current (step S). As a result, a state in which thrust generated by the motor (first electric actuator) is maintained by the parking brake locking mechanism, and accordingly the operative and inoperative states of the parking brake can be understood easily. Further, detection of the motor current is performed using a current sensor that is also used to realize a function of the motor (a function for moving brake pads toward a disc rotor), and hence separate current detection means need not be provided. Accordingly, the operative or inoperative state of the parking brake can be understood by means of a simple constitution, enabling a reduction in the cost of the apparatus.