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:
Mar. 01, 2005
Filed:
Jan. 10, 2002
Takashi Kambara, Osaka, JP;
Toshiaki Nakamura, Osaka, JP;
Miki Kotani, Osaka, JP;
Hirofumi Konishi, Osaka, JP;
Toshifumi Tanaka, Osaka, JP;
Takashi Kambara, Osaka, JP;
Toshiaki Nakamura, Osaka, JP;
Miki Kotani, Osaka, JP;
Hirofumi Konishi, Osaka, JP;
Toshifumi Tanaka, Osaka, JP;
Matsushita Electric Works, Ltd., Kadoma, JP;
Abstract
An improved ballast for a discharge lamp includes a DC—DC converter which receives an input DC voltage from a voltage source to provide a pre-starting voltage to make the lamp ready for being ignited or started. The DC—DC converter has a switching element which is driven to turn on and off for generating the pre-starting voltage. A start-accelerating means in included in the ballast in order to vary at least one of the switching frequency and the on-period of the switching element based upon the monitored input DC voltage in a direction of accelerating the increase of the output DC voltage to the pre-starting voltage until the output DC voltage reaches the pre-starting voltage.