Abstract An igniter for an internal combustion engine using a semiconductor switch is disclosed. A voltage dropping element is selectively inserted in a feeding circuit of an ignition coil of the engine which is connected to a DC electric source during the time of initiation of the engine or during a normal operation so as to compensate for a battery voltage drop at the time of initiation of the engine. A diode is provided for feeding a base current directly to the semiconductor switch at the time of ignition of the engine by short-circuiting the voltage dropping element at such time. A decrease in the base current of the semiconductor switch at the time of initiation of the engine, due to the voltage dropping element, is thereby avoided. The semiconductor switch is thus sufficiently conducted at the time of initiation of the engine, such that sufficient current is fed to the ignition coil so as to improve the ignition efficiency at the time of initiation of the engine.
An igniter for an internal combustion engine, which comprises: an electric power source; an ignition coil having a primary winding; a resistor connected between said power source and said primary winding of said ignition coil during the normal operation of said engine; means connecting said power source directly to a terminal of said primary winding during the cranking operation of said engine; a semiconductor switch for switching the electric current through said primary winding, said semiconductor switch including a base circuit connected directly to said power source during the normal operation of said engine; diode means connected between said base circuit and said terminal of said primary winding for increasing the conduction of said semiconductor switch during the cranking operation of said engine thereby increasing the voltage at said terminal of said primary winding whereby the current from said power source through said primary winding is increased during said cranking operation of said engine.
Claim 2
Dependent Claim
154 words
An igniter for an internal combustion engine, which comprises: an electric power source; an ignition coil having a primary winding; a resistor connected between said power source and said primary winding of said ignition coil during the normal operation of said engine; means connecting said power source directly to a terminal of said primary winding during the cranking operation of said engine; a semiconductor switch for switching the electric current through said primary winding, said semiconductor switch including a base circuit connected directly to said power source during the normal operation of said engine; diode means connected between said base circuit and said terminal of said primary winding for increasing the conduction of said semiconductor switch during the cranking operation of said engine thereby increasing the voltage at said terminal of said primary winding whereby the current from said power source through said primary winding is increased during said cranking operation of said engine.
Claim 3
Dependent Claim
56 words
The igniter for an internal combustwon engine according to claim 1, further comprising a second diode connected directly between said base circuit and said power source during the normal operation of said engine, said second diode connected in parallel with said first diode means and biased so as to feed electric current to said base circuit.