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:
Jan. 09, 2001
Filed:
Sep. 30, 1999
Toshimitsu Oka, Aichi-ken, JP;
Koji Aoki, Aichi-ken, JP;
Hideyuki Kanie, Aichi-ken, JP;
Hitoshi Ishikawa, Aichi-ken, JP;
Aisin Seiki Kabushiki Kaisha, Kariya, JP;
Abstract
A device for determining a rotational number of an electric dc motor which drives a moving body of an automobile accessory such a sunroof, or a glass pane of a power window includes a switched capacitance filter for eliminating noise from the motor, a cutoff frequency of the switched capacitance filter being dependent on a clock input thereof; a pulse shaping circuit for generating a ripple pulse signal indicative of the rotational number of the motor by wave-shaping an output of the switched capacitance filter; and a pulse generating circuit providing an output pulse signal so as to establish a condition wherein the frequency of the ripple pulse signal is equalized to the cutoff frequency of the a switched capacitance filter.