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:
Apr. 12, 1977
Filed:
Nov. 25, 1975
Leonard Woldring, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a capacitively stabilized discharge lamp shunted by a coil. During the starting procedure of the lamp the coil is brought into saturation so that, by means of resonance with the capacitive ballast, a high voltage is applied across the lamp to start it. The B-H magnetization curve of the coil has been chosen so that a transition from the unsaturated condition to the saturated condition also occurs during the operating condition of the device, namely just before the lamp is extinguished during each half cycle of the a.c. supply voltage. Consequently the ratio of the r.m.s. voltage of the a.c. voltage source to the operating voltage of the lamp may be relatively small. A resistor having a positive temperature coefficient shunts the lamp and is in series with the coil so as to limit the electric current if the lamp refuses to start.