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:
Dec. 17, 1991
Filed:
Sep. 28, 1990
Tsutomu Kakitani, Yokohama, JP;
Toshiba Lighting and Technology Group, Tokyo, JP;
Abstract
The invention circuit for a discharge lamp comprising a first switching circuit, a series resonant circuit, and a current transformer. The series resonant circuit energizes the discharge lamp by means of resonant output corresponding to the output from the first switching circuit. The current transformer incorporates the first, second, and the third windings. When the first winding inserted in the series resonant circuit is driven, the first winding outputs a predetermined amount of current to the second and third windings. The inverter circuit further comprises a second switching circuit, a pair of time constant circuits, and a control circuit. The second switching circuit controls ON-OFF operation of the first switching circuit in response to the output from the second winding. A pair of time constant circuits respectively contains the predetermined time constant values, and based on the predetermined time constant, each of the time constant circuits controls the switching timing of the second switching circuit. The control circuit controls the time constant of these time constant circuits in response to the output from the third winding of the current transformer.