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. 19, 1999
Filed:
May. 22, 1998
Hiroshi Onuki, Hitachinaka, JP;
Takashi Ito, Hitachinaka, JP;
Katsuaki Fukatsu, Naka-gun, JP;
Ryoichi Kobayashi, Tokai-mura, JP;
Noboru Sugiura, Miro, JP;
Abstract
According to the invention, a primary winding of an ignition coil is coupled with an insulated-gate bipolar transistor (IGBT). The IGBT is controlled by a current restriction circuit, which includes a control transistor for performing the on-off operation of the IGBT such that the IGBT is made conductive upon occurrence of an ignition control signal, and nonconductive, when a primary current of the ignition coil reaches a certain value depending on a reference voltage determined by a bias circuit. The bias circuit has a condenser, which is charged by a base current of the control transistor to change the base potential of the transistor slowly, when the transistor is made nonconductive.