Phase control device which compensates for input variations

Claim 2

A phase control device, comprising: (a) an a.c. power source; (b) a full wave rectifying circuit connected to said a.c. power source and for rectifying an input a.c. voltage from said a.c. power source; (c) a synchronous signal generating circuit also connected to said a.c. power source and for generating a synchronous signal based on the input a.c. voltage; (d) a comparison signal generating circuit connected to said full wave rectifying circuit and said synchronous signal generating circuit and for generating a comparison signal for every half a.c. wave upon its receipt of said synchronous signal; (e) a power source different from said input a.c. power source for producing a preset phase control angle signal; (f) a comparison circuit for directly comparing said comparison signal from said comparison signal generating circuit with said preset phase control angle signal from said different power source, and for obtaining a control signal for the phase control; and (g) at least one phase control element connected with said comparison circuit, and rendered conductive by an output from said comparison circuit.

Claim 3

A phase control device, comprising: (a) an a.c. power source; (b) a full wave rectifying circuit connected to said a.c. power source to rectify an input a.c. voltage from said a.c. power source; (c) a synchronous signal generating circuit also connected to said a.c. power source to generate a synchronous signal based on the input a.c. voltage; (d) a comparison signal generating circuit connected to said full wave rectifying circuit and said synchronous signal generating circuit to generate a comparison signal for every half a.c. wave upon receipt of said synchronous signal; (e) a holding circuit connected to said comparison signal generating circuit to hold therein the maximum value of an output therefrom; (f) a signal reversing circuit also connected to said comparison signal generating circuit to reverse the direction of a comparison signal waveform derived therefrom; (g) a variable resistor connected to said holding circuit to divide an output voltage from said holding circuit so as to establish a preset phase control angle signal; (h) a comparison circuit to directly compare said comparison signal from said comparison signal generating circuit with said preset phase control angle signal to be obtained from a different power source from said a.c. power source, and to obtain a control signal for the phase control; and (i) at least one phase control element connected with said comparison circuit, said element being rendered conductive by an output from said comparison circuit.

Claim 4

A phase control device, comprising: (a) an a.c. power source; (b) a full wave rectifying circuit connected to said a.c. power source to rectify an input a.c. voltage from said a.c. power source; (c) a synchronous signal generating circuit also connected to said a.c. power source to generate a synchronous signal based on the input a.c. voltage; (d) a comparison signal generating circuit connected to said full wave rectifying circuit and said synchronous signal generating circuit to generate a comparison signal for every half a.c. wave upon receipt of said synchronous signal; (e) a holding circuit connected to said comparison signal generating circuit to hold therein the maximum value of an output therefrom; (f) a signal reversing circuit also connected to said comparison signal generating circuit to reverse the direction of a comparison signal waveform derived therefrom; (g) a variable resistor connected to said holding circuit to divide an output voltage from said holding circuit so as to establish a preset phase control angle signal; (h) a comparison circuit to directly compare said comparison signal from said comparison signal generating circuit with said preset phase control angle signal to be obtained from a different power source from said a.c. power source, and to obtain a control signal for the phase control; and (i) at least one phase control element connected with said comparison circuit, said element being rendered conductive by an output from said comparison circuit.

Claim 5

The device as set forth in claim 2, wherein a plurality of integration circuits constituting said comparison signal generating circuit are connected in parallel.

Claim 6

The device as set forth in claim 2, wherein a pluraity of integration circuits constituting said comparison signal generating circuit are serially connected to enable the integration operations to be conducted for a plurality of times after an output from said full wave rectifier circuit has passed through a square circuit therein.

Claim 7

The device as set forth in claim 2, wherein said comparison signal generating circuit comprises a square circuit, a VF converter, photocell means to convert an output from said full wave rectifier into pulse number, and said holding and signal reversing circuits include a plurality of memory circuits and subtraction counter to store said pulse number and to count down the contents of said memory circuits.