Lamp dimmer
First Claim
1. A lamp dimmer for connection to at least one lamp circuit for interrupting a portion of each positive and negative half cycle of applied distribution line current to the lamp circuit, comprisingdiode routing means connected to the distribution line and to the lamp circuit for providing line voltage to the lamp circuit,an electronic switch connected to provide means for interrupting voltage through said diode routing means,a photocontroller including a photocontrol driver and a photocontrol receiver for operating said electronic switch,an automatically adjustable pulse timer for pulse operating said photocontrol driver, the output therefrom being adjustable with respect to pulse width within the first part of each half cycle of applied line voltage as dependent on the location of the onset of the timer operation,a delay timer connected to said pulse timer for determining the onset of timer operation of said photocontrol driver,a zero-crossing detector for producing an output with each line voltage zero-crossing and connected to said delay timer, andinput means for determining the amount of dimming, said input means being connected to said delay timer, the level output determining the output of said delay timer with respect to said zero-crossing output of said detector.
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Accused Products
Abstract
A lamp dimmer suited for fluorescent and other lamps which controllably notches the applied voltage to a lamp circuit each half cycle. Progressively larger dimming control voltages produces progressively wider notches as well as progressively causing the notches to be further from the zero-crossing occurrence toward the peak occurrence of the half cycles, thereby providing means for varying power to the light circuit. Optocoupler means is employed with respect to a power output bridge to isolate the control circuit from the power output circuit to the lamp. A photosensor used to sense the ambient light conditions is used to produce the dimming control voltage so as to achieve a balancing effect between the ambient and the artificial light produced by the lamp.
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Citations
11 Claims
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1. A lamp dimmer for connection to at least one lamp circuit for interrupting a portion of each positive and negative half cycle of applied distribution line current to the lamp circuit, comprising
diode routing means connected to the distribution line and to the lamp circuit for providing line voltage to the lamp circuit, an electronic switch connected to provide means for interrupting voltage through said diode routing means, a photocontroller including a photocontrol driver and a photocontrol receiver for operating said electronic switch, an automatically adjustable pulse timer for pulse operating said photocontrol driver, the output therefrom being adjustable with respect to pulse width within the first part of each half cycle of applied line voltage as dependent on the location of the onset of the timer operation, a delay timer connected to said pulse timer for determining the onset of timer operation of said photocontrol driver, a zero-crossing detector for producing an output with each line voltage zero-crossing and connected to said delay timer, and input means for determining the amount of dimming, said input means being connected to said delay timer, the level output determining the output of said delay timer with respect to said zero-crossing output of said detector.
Specification