Vehicular headlight providing high-beam and depressed-beam illumination, and light source therefor

US5725298A · kind A · utility

Assignees

• Hella KGaA Hueck & Co. · DE
• Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

• Franz-Josef Kalze · Harsewinkel, DE
• Wolfgang Peitz · Warstein, DE
• Rolf Kiesel · Aalen, DE

Key dates

• Filing date: Feb 20, 1997
• Grant date: Mar 10, 1998
• Expiry date: Feb 20, 2017

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J61/025
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

To provide for improved light distribution of a vehicular headlight furning both depressed-beam and high-beam illumination, a shadow cap (9, 25) partly surrounds a main light source, typically filaments of halogen incandescent lamp, located in a reflector (2) which has two segments (14, 15) of different contours. The first one (14) of the reflector segments is optically associated with the main filament furnishing depressed-beam illumination, and this segment has a free-formed surface reflection contour. A second segment of the reflector is optically associated with an auxiliary filament (8, 18). The shadow cap (9, 25) provides a shadow angle of between 100.degree. and 140.degree. with respect to light emitted from the main filament (7) to define a shadow zone (12) and a light zone (13) on the reflector. The shadow cap is shaped and positioned with respect to the auxiliary filament (8, 18) such that the auxiliary filament is located within the shadow zone (12). The auxiliary filament is located by an offset of between 0.25 and 2 times below the optical axis (A) of the reflector, and the spatial distribution of the segments is such that the reflector is associated with a light zone …