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:
Sep. 26, 2006
Filed:
Mar. 11, 2004
Yasuyoshi Numajiri, Shizuoka, JP;
Ken Kato, Shizuoka, JP;
Shigeyoshi Yotoriyama, Shizuoka, JP;
Kiyotaka Fukawa, Shizuoka, JP;
Masao Okawa, Shizuoka, JP;
Yasuyoshi Numajiri, Shizuoka, JP;
Ken Kato, Shizuoka, JP;
Shigeyoshi Yotoriyama, Shizuoka, JP;
Kiyotaka Fukawa, Shizuoka, JP;
Masao Okawa, Shizuoka, JP;
Koito Manufacturing Co., Ltd., Tokyo, JP;
Abstract
Lamp units for radiating a beam ahead of a vehicle in a light distribution pattern are housed in a lamp body. Illumination of the auxiliary lamp units is controlled based on driving conditions. Illumination control means extinguish light through dimming by gradually decreasing voltage applied to the light sources. When the applied voltage has dropped to a threshold value, the applied voltage is controlled to zero immediately. Compared to when the lamps remaining in an illuminated state are suddenly extinguished, a change in quantity of light is mild, and no uncertainty arises. Below a threshold value where the applied voltage gradually drops to the threshold value and a change may arise in the filament crystalline structure due to annealing at a transition temperature, the applied voltage approaches zero. Hence, the filament does not pass from the transition temperature while being rapidly cooled, thus avoiding filament crystalline structure change.