Light dimming system for grounded-side control of discrete indicator lamps
AssigneeBoeing Vertol Company
InventorsClark W. Sechler, Archie T. Sherbert, Jr.
Life of this patent
Estimating the term…
Abstract
A light dimming system for simultaneously controlling the brightness of a plurality of two-terminal indicating lights, each having one terminal connected to receive a constant voltage relative to ground. The system includes a single dimmer control for producing an arbitrarily variable control voltage, and a like plurality of interface circuits, connected between the dimmer control and the other terminals of the indicating lights, respectively, for varying the voltage at the other terminals of the indicating lights proportional to the control voltage supplied to the interface circuits from the dimmer control.
Claims8
Light dimming apparatus, which comprises:
- voltage supply means for supplying a substantially constant supply voltage relative to ground;
- dimmer control means, connected to receive the supply voltage, for producing an arbitrarily variable control voltage relative to ground;
- and
- at least one light circuit which includes
- a two terminal, electrically-actuated, light emitter having one terminal connected to receive the supply voltage, and
- interface circuit, having an input terminal connected to receive the supply voltage, a control terminal connected to receive the control voltage, and an output terminal connected to the other terminal of the light emitter, for producing at its output terminal an output voltage relative to ground which is proportional to the difference of the supply voltage and the control voltage, whereby the voltage across the ligh emitter is proportional to the control voltage.
Dependencies are inferred from the claim text.