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US 4,363,622 AGranted
Combustion flashbulb
AssigneeU.S. Philips Corporation
InventorAloysius M. M. van Laarhoven
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AssigneeU.S. Philips Corporation
InventorAloysius M. M. van Laarhoven
Estimating the term…
Combustion flashbulbs according to the invention have a light-pervious lamp envelope (1) filled with a tangled mass (5) of actinically combustible metal strips and an oxidizing gas. Current supply conductors (2, 3) are coated on parts situated within the lamp envelope with a dispersion (4) of metal powder in binder. This dispersion (4) adheres strips of the mass (5) to the current conductors (2, 3). The bulb can be ignited by a current pulse of approximately 25 V. Another method of igniting is to produce breakdown by applying a short-lasting voltage of approximately 25 V across the conductors (2, 3), afterwards succeeded by a filament current having a voltage of approximately 10 V. If the metal in the dispersion (4) is a nobler metal, the bulbs can be ignited with a current source of 10 V without preceding breakdown. The bulbs are simple of construction, rapid, and give a short-lasting lightflash.
A combustion flashbulb having a sealed vacuum-tight light-pervious lamp envelope which is filled with an oxidizing gas and a mass of actinically-combustible metal strips, in which current conductors extend at a distance from each other from outside the envelope through the wall thereof into the lamp envelope and are there each in contact with the mass of metal strips, said bulb having means to electrically ignite the bulb, characterized in that the current conductors inside the lamp envelope are coated at least locally with a dispersion of a metal powder in a binder and that the igniting means of the bulb consist of the current conductors and a part of the mass of metal strips, which part is adhered to the current conductors by means of the dispersion of metal powder in a binder.
Dependencies are inferred from the claim text.