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. 04, 1978
Filed:
Feb. 28, 1977
Edward W Morton, Bronx, NY (US);
John F Gilmore, Verona, NJ (US);
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Abstract
There is provided in combination with a rapid-start series-sequence type ballast for two low-pressure mercury discharge lamps, apparatus for reducing the power consumption of both lamps. The apparatus utilizes switch means in conjunction with a capacitor to limit the current supply to the lamps after the lamps are energized. The switch means has two members in series circuit arrangement with one of the electrodes of one of the lamps. Each member is connected on opposite sides of the electrode. The capacitor is connected in parallel circuit arrangement with one of the members. Initially upon energization the switch means has a low impedance state to permit current flow and then switches to a high impedance state. The switch means permits preheating of the electrode and thereafter upon response to current flow switches and causes the lamp current to pass through the capacitor and thereby decrease by a predetermined amount the current through the normally operating lamps. The switch means may comprise switch members having a positive temperature coefficient of electrical resistance.