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. 16, 2007
Filed:
Aug. 20, 2003
Yasuharu Hourai, Utsunomiya, JP;
Yasuharu Hourai, Utsunomiya, JP;
Keihin Corporation, Tokyo, JP;
Abstract
An excitation control circuit for suitably exciting a solenoid while current consumption and heating are effectively reduced. The control circuit has a driving circuit for driving a coil of a solenoid in response to a pulse signal supplied from an external device; a counter-electromotive force absorbing circuit, inserted in a path of a return current of the coil, for absorbing counter-electromotive force produced by the coil; and a return current circuit, connected in parallel to the counter-electromotive force absorbing circuit, for intermittently bypassing the return current. The return current circuit may have a field effect transistor switched on according to a signal for defining the timing of bypassing the return current, where the current path of the transistor is connected between a positive electrode and a negative electrode of the coil.