Power line switch with time delay turn off

Claim 1

A power conservative time delay cut-off switch having a power on and power cut-off state for permitting a load to receive power from a power source for a predetermined event actuated period of time corresponding to the time that the switch is in the power on state and which draws no power in the power off state, comprising: a. a first switching device which has a conductive and a non-conductive state and includes input, output and control teminals, said input terminal being coupled to said power source and said output terminal being coupled to said load, for permitting power to reach said load while said device is in its conductive state; b. bias means; c. a second switching device which has a conductive and a non-conductive state and includes input, output and control terminals, said input terminal of said second device being coupled to said bias means and said output terminal of said second device being resistively coupled to the control terminal of said first device, for placing and maintaining said first device in the same conductivity state as said second device; d. means for providing a pulse of short duration to said second device to initially place said second device in its conductive state; e. means for storing an electric charge over said predetermined period which includes a first and second terminal, said first terminal being coupled to the output terminal of said first device and said second terminal being coupled, through a resistance of high impedance, to ground, for developing an electric charge for storage while said first device is in its conductive state; and f. means for varying the potential on the control terminal of said second device, coupled between said second device and said means for storing, directly as a function of the electric charge stored by said means for storing.