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. 27, 2011
Filed:
Feb. 25, 2009
Xuefei Xie, ShangHai, CN;
Gang Yao, Shang Hai, CN;
Chenghua Zhu, ShangHai, CN;
BO Zhang, ShangHai, CN;
Xuefei Xie, ShangHai, CN;
Gang Yao, Shang Hai, CN;
Chenghua Zhu, ShangHai, CN;
Bo Zhang, ShangHai, CN;
General Electric Company, Schenectady, NY (US);
Abstract
The present disclosure thus provides a technique for providing multi-level operation of ballast circuitry for discharge lamps. In one version, an auxiliary capacitance is switched in and out of circuit by a user controlled switch for lower the frequency of the voltage from the inverter to the transformer resulting in lower power output to the lamps. In another version, the auxiliary capacitance may be switched in and out of circuit by a user operated switch wherein the capacitance is connected to the secondary or output winding of the transformer for selectively reducing power to the lamps for reduced illumination. In other versions, auxiliary inductances are selectively switched in and out of circuit to alter the frequency of the primary voltage to the transformer. In another version, an auxiliary winding is selectively switched in and out of the secondary of the transformer for providing normal and reduced level power to the lamps. In another version, a variable direct current power supply is provided to the coupled inductors of the ballast circuitry for user control of the power supply to the ballast circuitry.