Sealed beam headlights

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In the case of sealed beam headlights , the actual light source ( incandescent lamp or halogen lamp ) is inseparably connected to the reflector, which bundles the light, and to the closed, transparent housing, which can be made of glass or polycarbonates , to form a unit ("pressed glass bulb") ( sealed beam means in English literally sealed [light] ray ). Therefore they are weatherproof (the reflector cannot be damaged by penetrating water) and can be used outdoors without further protective measures. They can contain several light sources - separate filaments in the case of incandescent lamps. The disadvantage is that the entire headlight has to be replaced when it burns out.

Embodiments

Sealed beam lamps come in different housing sizes as PAR spotlights with a circular light exit surface and are mainly used in stage lighting technology , for shop window lighting and in the garden area.

Headlights in motor vehicles

Sealed beam headlights were mandatory on automobiles in the United States from 1940 to 1983; the limited range of types of this headlight technology severely restricted the possibility of vehicle front design. Car models imported into the USA were often downright defaced by the compulsion to install sealed beam headlights. B. the steering headlights of the Citroën DS built from 1967 onwards. Since May 1, 1997, the main headlights approved in the USA have been compliant with ECE regulation R 1 and R 8.

  • Mercedes-Benz 107 series : on the left with the German headlight version, on the right in the US version with sealed beam headlights

  • Example Citroën DS

In Germany , sealed-beam headlights were banned for motor vehicles made in Germany; US import models could be equipped with it.

Individual evidence

  1. ^ Robert Bosch GmbH: Kraftfahrtechnisches Taschenbuch. 26th, revised and supplemented edition. Friedr. Vieweg & Sohn, Wiesbaden 2007, ISBN 978-3-8348-0138-8 , p. 957.
  2. ↑ Expertise in automotive engineering. 2nd Edition. Holland + Josenhans Verlag, Stuttgart 1982, ISBN 3-7782-3520-6 , p. 364.