Vehicle headlamp
US4246631A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1979 |
| Grant date | Jan 20, 1981 |
| Priority date | — |
| Expiry date | May 14, 1999 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21S41/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A vehicle headlamp for producing a Z-beam pattern has a reflector provided with a reflective area lying on a surface defined by rotating an ellipse about an axis which passes through the inner focus of the ellipse and which is inclined an acute angle (1.degree.-2.degree.) to the focal axis of the ellipse. A shielded filament for producing an inclined cut-off line to the beam is used and is orientated in the opposite sense to that in which it is orientated in a conventional headlamp for producing an inclined cut-off. Lensing at the front of the reflector splits the area of the basic beam pattern immediately below a horizontal portion of the cut-off line into parts which define upper and lower, mutually laterally displaced horizontal cut-off portions in the required Z-beam pattern. The lensing also utilizes a part-circular cut-off portion of the basic beam produced by the reflector and bulb to define an inclined portion of the Z-beam and depress and/or shifts other portions of the basic beam to reinforce other portions of the Z-beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.