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:
Nov. 19, 2002
Filed:
Jul. 23, 2001
Isaac Lynnwood Flory, IV, Blacksburg, VA (US);
Hubbell Incorporated, Orange, CT (US);
Abstract
An apparatus and method are provided for operating one of a plurality of lamps employed within a luminaire via a single ballast, thereby extending the operational life of the luminaire. The operating lamp disables the lamps downstream from itself by preventing current from conducting through lamps other than the operating lamp. The lamps upstream from the operating lamp typically lack a sufficient voltage for ignition and operation. However, if any of the upstream lamps begin to operate, the lamps operating downstream cease to operate. In the event that two lamps begin to operate in an asymmetric manner, a capacitor is preferably provided to maintain a reverse voltage with respect to the output of the ballast, thus ensuring reduced voltage across the rectified lamps until one lamp extinguishes and the second lamp begins to operate.