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:
Oct. 21, 2003
Filed:
May. 22, 2002
Akihiro Yanai, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
A valve is urged in the valve-opening direction by an upper spring and in the valve-closing direction by a lower spring. The valve is thus urged to a neutral position where the respective urging forces are balanced. The valve is controlled to be released from one of two terminal positions, that is, the full-open position or the full-closed position, and to be attracted to the position from which the valve has been released. The displacement pattern of the valve during this period is sensed by a displacement amount sensor, whereby the maximum displacement amount of the valve from that terminal position is measured. The change of the neutral position is detected based on the change of the measured maximum displacement amount with respect to a reference value.