Patent ID: 6522087
Filing Date: 2003-02-18
Classification: H05B

Abstract:
An ignition circuit comprising:master switch circuit, ignition, and first timer control circuit; fuse, PTC, full wave bridge rectifier, MOSFET, inverse circuit composed by inverse transistor and inverse resistor form the master switch circuit; AC power source, fuse, PTC, and the AC terminals of full wave bridge rectifier are connected in serial; a positive terminal of said full wave bridge rectifier is connected to a drain terminal of said MOSFET and one junction of inverse resistor, a negative terminal of said full wave bridge rectifier is connected to a source terminal of MOSFET and an emitter of the inverse transistor a collector of said inverse transistor is connected to a gate terminal of said MOSFET and another junction of said inverse resistor, a base of said inverse transistor is connected to the collector of the ignition transistor and one junction of resistor of the ignition circuit; divided circuit, time coefficient resistor, time coefficient capacitor, ignition resistor, and ignition transistor form and ignition circuit; two serial resistors compose divided circuit, one junction of said resistor is connected to a positive terminal of said full wave bridge rectifier, the one junction of resistor is connected to the negative terminal of full wave bridge rectifier, and a center junction of the divided resistors is connected to one junction of time coefficient resistor; another junction of said time coefficient resistor is connected to a positive terminal of said time coefficient capacitor and a base of said ignition transistor, a negative terminal of said time coefficient capacitor is connected to the negative terminal of full wave bridge rectifier; a collector of said ignition transistor is connected to one junction of ignition resistor and the base of inverse transistor, the emitter of ignition transistor is connected to a negative terminal of said full wave bridge rectifier, the base of the ignition transistor is connected to the positive terminal of said time coefficient capacitor, the other junction of said ignition resistor is connected to the positive terminal of full wave bridge rectifier; the base of the ignition transistor is connected to the emitter of a PNP type transistor of the first time control circuit; power supply circuit, timer IC circuit, and control transistor circuit form the first time control circuit; power supply circuit is formed by a zener diode, forward action diode, step-down resistor, zener diode, and filter capacitor; an N junction of said zener diode is connected to the positive terminal of said full wave bridge rectifier, a P junction of said zener diode is connected to the P junction of forward action diode, the N junction of said forward action diode is connected to the one junction of said step-down resistor, the zener diode, forward action diode, and step-down resistor are connected in serial, the other junction of said resistor is connected to the N junction of zener diode, positive terminal of filter capacitor, and the positive terminal of the timer IC, the P junction of zener diode, negative terminal of filter capacitor and the negative terminal of timer IC is connected to the negative terminal of said full wave bridge rectifier; timer IC circuit is a standard astatic with independently controllable timing periods circuit, the output terminal of the timer IC is connected to the one junction of divided resistor, the center junction of divided resistors is connected to the said base of control transistor, the other junction of resistor is connected to the negative terminal of said fill wave bridge rectifier; and control transistor is a PNP type transistor, the emitter of the transistor is connected to the base of the ignition transistor of ignition circuit, the base of transistor is connected to the center junction of divided resistors, the collector of transistor is connected to the negative terminal of full wave bridge rectifier, and consist of at least one of the following, fuse, thermal fuse, or semiconductor fuse.