Lighting control system for incandescent lamps

Claim 1

An apparatus for operating an electric light comprising: a bistable device having at least one gate terminal and a pair of main terminals connected in series with the electric light and a source of alternating current power; means operatively connected to said source of AC power and said gate terminal for generating an electrical signal so as to cause the impedance between the main terminals of said bistable device to change from a high non-conducting state to a low conducting state during a portion of the alternating current cycle; a switch having an ON position and an OFF position; automatic means for producing a progressive increase in the phase time of each succeeding AC cycle at which the bistable device changes from a high impedance non-conducting state to a low impedance conducting state, following a change to the ON state of said switch, said automatic phase increase means comprising: a network including a capacitor and a temperature sensitive resistive element; means for heating said temperature sensitive resistive element when the state of said switch is changed so as to cause said element to alter its resistance, and wherein said temperature sensitive resistive element and said means for heating said temperature sensitive resistive element comprises a self-heated thermistor; and further including: automatic means for producing a progressive decrease in the phase time of each succeeding cycle at which the bistable device changes from a high impedance non-conducting state to a low impedance conducting state following a change in the state of said switch to the OFF state.

Claim 2

An apparatus for operating an electric light comprising: a bistable device having at least one gate terminal and a pair of main terminals connected in series with the electric light and a source of alternating current power; means operatively connected to said source of AC power and said gate terminal for generating an electrical signal so as to cause the impedance between the main terminals of said bistable device to change from a high non-conducting state to a low conducting state during a portion of the alternating current cycle; a switch having an ON position and an OFF position; automatic means for producing a progressive increase in the phase time of each succeeding AC cycle at which the bistable device changes from a high impedance non-conducting state to a low impedance conducting state, following a change to the ON state of said switch, said automatic phase increase means comprising: a network including a capacitor and a temperature sensitive resistive element; means for heating said temperature sensitive resistive element when the state of said switch is changed so as to cause said element to alter its resistance, and wherein said temperature sensitive resistive element and said means for heating said temperature sensitive resistive element comprises a self-heated thermistor; and further including: automatic means for producing a progressive decrease in the phase time of each succeeding cycle at which the bistable device changes from a high impedance non-conducting state to a low impedance conducting state following a change in the state of said switch to the OFF state.

Claim 4

An apparatus for operating an electric light comprising: a bistable device having at least one gate terminal and a pair of main terminals connected in series with the electric light and a source of alternating current power; means operatively connected to said source of AC power and said gate terminal for generating an electrical signal so as to cause the impedance between the main Terminals of said bistable device to change from a high non-conducting state to a low conducting state during a portion of the alternating current cycle; a switch having an ON position and an OFF position; automatic means for producing a progressive decrease in the phase time of each succeeding AC cycle at which the bistable device changes from a high impedance nonconductive state to a low impedance conducting state following a change to the OFF state of said switch, said automatic phase decreasing means comprising: a network including a capacitor and a temperature sensitive resistive element; means for heating said temperature sensitive resistive element during the time that said switch is in the ON state; means for decreasing the heat supplied by said heating means when said switch is changed to said OFF state.

Claim 5

An apparatus for operating an electric light comprising: a bistable device having at least one gate terminal and a pair of main terminals connected in series with the electric light and a source of alternating current power; means operatively connected to said source of AC power and said gate terminal for generating an electrical signal so as to cause the impedance between the main Terminals of said bistable device to change from a high non-conducting state to a low conducting state during a portion of the alternating current cycle; a switch having an ON position and an OFF position; automatic means for producing a progressive decrease in the phase time of each succeeding AC cycle at which the bistable device changes from a high impedance nonconductive state to a low impedance conducting state following a change to the OFF state of said switch, said automatic phase decreasing means comprising: a network including a capacitor and a temperature sensitive resistive element; means for heating said temperature sensitive resistive element during the time that said switch is in the ON state; means for decreasing the heat supplied by said heating means when said switch is changed to said OFF state.

Claim 9

An apparatus for operating a household incandescent light comprising: a variable impedance device having at least one control terminal and a pair of main terminals; means for connecting said main terminals in series with an electric light; and means for connecting a source of alternating current power to the series circuit comprised of said variable impedance device and light and; a manually operable switch having at least one ON position and one OFF position; means for supplying a control voltage to said control terminal so as to vary the impedance between the main terminals of said variable impedance device, said means including: a control network operatively connected to said switch and said control terminal, said network comprising at least one temperature sensitive resistive element whereby the impedance between the main terminals of said variable impedance device will be dependent upon the state of said switch and the temperature of at least one temperature sensitive resistive element included in said network; means for causing a temperature change of a control network temperature sensitive resistive element following a change in the state of said switch so as to produce a continuous variation in light intensity for an observable period; and further including a manually adjustable impedance means operably connected to said control terminal of said variable impedance element for adjusting the steady state intensity of the light.

Claim 10

An apparatus for operating a household incandescent light comprising: a variable impedance device having at least one control terminal and a pair of main terminals; means for connecting said main terminals in series with an electric light; and means for connecting a source of alternating current power to the series circuit comprised of said variable impedance device and light and; a manually operable switch having at least one ON position and one OFF position; means for supplying a control voltage to said control terminal so as to vary the impedance between the main terminals of said variable impedance device, said means including: a control network operatively connected to said switch and said control terminal, said network comprising at least one temperature sensitive resistive element whereby the impedance between the main terminals of said variable impedance device will be dependent upon the state of said switch and the temperature of at least one temperature sensitive resistive element included in said network; means for causing a temperature change of a control network temperature sensitive resistive element following a change in the state of said switch so as to produce a continuous variation in light intensity for an observable period; and further including a manually adjustable impedance means operably connected to said control terminal of said variable impedance element for adjusting the steady state intensity of the light.

Claim 13

An apparatus for operating an incandescent lamp comprising: a variable impedance device having at leaSt one control terminal and first and second main terminals; means for connecting the 1st main terminal of said variable impedance device to one side of a household AC main''s supply; means for connecting the second main terminal of said variable impedance device to one terminal of an incandescent lamp which has the opposite terminal connected to the other side of the AC main''s supply; a 1st switch having at least two positions; a network operatively connected to said control terminal and said 1st switch, said network including means for applying a signal to said control terminal to vary the impedance of said variable impedance device so as to produce a continuous decrease in the light intensity of said lamp for a period of at least two seconds following a change in the state of said switch to one position.

Claim 14

An apparatus for operating an incandescent lamp comprising: a variable impedance device having at leaSt one control terminal and first and second main terminals; means for connecting the 1st main terminal of said variable impedance device to one side of a household AC main''s supply; means for connecting the second main terminal of said variable impedance device to one terminal of an incandescent lamp which has the opposite terminal connected to the other side of the AC main''s supply; a 1st switch having at least two positions; a network operatively connected to said control terminal and said 1st switch, said network including means for applying a signal to said control terminal to vary the impedance of said variable impedance device so as to produce a continuous decrease in the light intensity of said lamp for a period of at least two seconds following a change in the state of said switch to one position.