초록 ▼

A power controller having first and second power outlets, connections between one side of an A.C. line to one side of each outlet, a current sensing impedance connected between the other side of the A.C. line and the other side of the first power outlet, a triac connected between the other side of t

A power controller having first and second power outlets, connections between one side of an A.C. line to one side of each outlet, a current sensing impedance connected between the other side of the A.C. line and the other side of the first power outlet, a triac connected between the other side of the A.C. line and the other side of the second power outlet, a first operational amplifier normally maintaining the triac in a non-conductive condition and a second operational amplifier to cause current to flow through the triac to the second power outlet after a selected time delay whenever an appliance such as a power tool that is coupled to the first power outlet draws a given amount of current through the sensing impedance.

대표청구항 ▼

A power control circuit comprising: first and second A.C. power input terminals, a first power outlet having two contacts, a second power outlet having two contacts, a connection from said first input terminal to one contact in each power outlet, a sensing impedance connected between said second inp

A power control circuit comprising: first and second A.C. power input terminals, a first power outlet having two contacts, a second power outlet having two contacts, a connection from said first input terminal to one contact in each power outlet, a sensing impedance connected between said second input terminal and the other contact of said first power outlet, a triac having a gate and two terminals, a connection between one of said terminals of said triac and the other contact of said second power outlet, a connection between the other of said terminals of said triac and said second input terminal, control means for applying a voltage to said gate so as to prevent current from flowing between the terminals of said triac until a given time after a predetermined minimum value of current starts flowing in said sensing impedance and continues flowing for a given period.