Ignition system for an internal combustion engine

An internal combustion engine ignition system including at least one spark plug, means for firing the spark plug including a first solid state electronic switching device, and a triggering circuit for switching the first electronic switching device for firing the spark plug comprising:

• a second solid state electronic device, electromagnetic pulse generating means for generating a succession of electrical trigger pulses in timed relation to the operating cycle of the engine and which increase in amplitude with an increase in engine speed to make the second switching device electronically conductive for switching the first device, voltage bias means connected between the pulse generating means and the second switching device to advance with increase in engine speed the time in the engine cycle the second switching device is made conducting, and means for controlling the voltage of the bias means independently of pulse amplitude to control the time in the engine cycle the second switching device is conducting to control spark timing, the means for controlling the voltage on the bias means being connected in parallel with the bias means and including:
• a transisitor connected in parallel with said voltage biasing means;
• and
• means for operating said transistor in the active region of its operating characteristics wherein its circuit resistance varies during operation of the engine.

An ignition system for an internal combustion engine comprising:

• at least one spark plug, means for firing the spark plug including a first solid-state electronic switching device and a triggering circuit for switching the first electronic switching device, said triggering circuit comprising a second solid-state electronic switching device having a gate circuit, electromagnetic pulse generating means for generating a succession of electrical trigger pulses in timed relation to the operating cycle of the engine and which increase in amplitude with an increase in engine speed to make said second switching device electrically conductive to switch said first switching device, and means for preventing a portion of the trigger pulses from going to said second switching device and for varying the portion of the trigger pulse going to the second switching device, said means for preventing and varying the portion of the pulse going to the second switching device comprising:
• a parallel circuit comprised of a transistor connected in parallel with a capacitor, said parallel circuit connected to the gate circuit of said second solid state switching device;
• and
• means for operating said transistor in the active region of its operating characteristics wherein its circuit resistance varies during its operation.