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:
Jun. 02, 2009
Filed:
Mar. 28, 2005
Tohma Yamaguchi, Tokyo, JP;
Tohma Yamaguchi, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
When a solenoid is operated so as to move an engaging pawl to a disengaged position, if a displacement detection device (an angular position sensor and a controller) detects that a motor rotor has not been displaced by an amount equal to or exceeding a predetermined level, that is, if the motor has not returned by an amount equal to or exceeding the predetermined level within a predetermined time period, a defect in an unlocked condition (an unlocking failure of a park braking lock mechanism) is determined. In this case, a driver is notified of the failure, so that prompt action can be taken to rectify the unlocking failure of the park braking lock mechanism.