Ignition apparatus for internal combustion engine

An ignition apparatus for an internal combustion engine comprising, in combination:

• first means, responsive to the rotational speed of an engine, for generating a first signal for each rotational angle of the engine corresponding to a prescribed rotational angle;
• second means, coupled to said first means, for generating a second signal delayed in time by a period of time starting with the instant of the generation of said first signal;
• third means, coupled to said second means, for generating a third signal representative of the product of the length of time elapsed beginning with the instant of the generation of said second signal until the generation of the next first signal by said first means and a first predetermined coefficient, and for generating a fourth signal representative of the product of the length of time elapsed beginning with the instant of the generation of said next first signal independent of the speed of rotation of the engine and a second predetermined ccoefficient;
• fourth means, coupled to said third means, for generating an ignition timing signal when the level of said fourth signal reaches a predetermined value, said ignition timing signal being applied to a primary coil circuit of an ignition circuit for said engine, so that electromagnetic induction is caused in the primary coil of said primary coil circuit to generate high voltage ignition energy in a secondary coil of said ignition circuit.

An ignition apparatus for an internal combustion engine comprising, in combination:

• first means, responsive to the rotational speed of an engine, for generating a first signal for each rotational angle of the engine corresponding to a first portion of a prescribed rotational angle and a second signal subsequent to said first signal, for each rotational angle of the engine corresponding to a second portion of said prescribed rotational angle;
• second means, coupled to said first means, for generating a third signal delayed in time by a period of time starting with the instant of the generation of said first signal;
• third means, coupled to said first and second means, for generating a fourth signal representative of the product of the length of time elapsed beginning with the instant of the generation of said third signal by said second means until the generation of said second signal by said first means and a first predetermined coefficient, and for generating a fifth signal representative of the product of the length of time elapsed beginning with the instant of the generation of said second signal and second predetermined coefficient;
• fourth means, coupled to said third means, for generating an ignition timing signal when the level of said fifth signal reaches a predetermined value, said ignition timing signal being applied to a primary coil of an ignition circuit for said engine, so that electromagnetic induction is caused in said primary coil to generate high voltage ignition energy in a secondary coil of said ignition circuit.

An ignition apparatus for an internal combustion engine comprising, in combination:

• pickup means for generating one rotational angle signal for one ignition cycle of an internal combustion engine,
• a monostable multivibrator coupled to said pickup means and energized for a predetermined period of time in response to the rotational angle signal,
• a capacitor, coupled to said monostable multivibrator, and adapted to begin to be charged with a constant current immediately when said monostable multivibrator is de-energized and to begin to discharge with a constant current immediately when the next rotational angle signal is produced from said pickup means,
• a constant current charging circuit for charging said capacitor,
• a constant current discharging current for discharging said capacitor,
• a comparator circuit, coupled to said capacitor, for comparing a voltage across said capacitor with a predetermined reference voltage during the discharge of said capacitor, so as to generate an output signal when the voltage across said capacitor coincides with said reference voltage, and
• an ignition circuit, coupled to said comparator circuit, and adapted to be actuated in response to the signal produced by said comparator circuit.

An ignition apparatus for an internal combustion engine comprising:

• pickup means for generating a pair of rotational angle signals for each ignition cycle of an internal combustion engine;
• a monostable multivibrator coupled to said pickup means and being energized for a predetermined period of time in response to a rotational angle signal;
• a capacitor, coupled to said monostable multivibrator, and adapted to begin to be charged with a constant current immediately when said monostable multivibrator is de-energized and to begin to discharge with a constant current immediately when the next rotational angle signal is produced from said pickup means;
• a constant current charging circuit for charging said capacitor in response to a first one of said pair of rotational angle signals,
• a constant current discharging circuit for discharging said capacitor in response to the next one of said pair of rotational angle signals;
• a comparator circuit, coupled to said capacitor, for comparing a voltage across said capacitor with a predetermined reference voltage during the discharge of said capacitor, so as to generate an output signal when the voltage across said capacitor coincides with said reference voltage;
• and
• an ignition circuit, coupled to said comparator circuit, and adapted to be actuated in response to the signal produced by said comparator circuit.

An ignition apparatus for an internal combustion engine comprising, in combination:

• pickup means for generating one rotational angle signal for each ignition cycle of an internal combustion engine;
• first and second fixed frequency oscillators;
• a first counter actuated in response to the output signal from said pickup means and coupled to said first fixed frequency oscillator to count the output pulses of said first fixed frequency oscillator, so as to produce an output signal when the counted contents of said counter reach a predetermined number;
• an up-down counter adapted to be actuated in response to the output signal from said first counter to count up the output pulses from said first fixed frequency oscillator and then count down, in response to the next rotational angle signal with the output pulses of said second fixed frequency oscillator, from the number of said up counts;
• a comparator circuit, coupled to said up-down counter, for producing an output signal upon the contents of said counter reaching a predetermined value while said counter is effecting count-down operation;
• and
• an ignition circuit adapted to be actuated in response to the output signal from said comparator circuit.

An ignition apparatus for an internal combustion engine comprising, in combination:

• pickup means for generating a rotational angle signal with a width varying with the rotational speed of an engine;
• first and second fixed frequency oscillators;
• an up-down counter adapted to be actuated at the rising time of the output of said pickup means, to count up to the output pulses from said first fixed frequency oscillator, and then count down, from the up count, in response to output pulses of said second fixed frequency oscillator from the point of the falling time of the output signal from said pickup means;
• a comparator, coupled to said up-down counter, for producing an output signal upon the contents of said counter reaching a predetermined value while said counter is effecting a count-down operation;
• and
• an ignition circuit adapted to be actuated in response to the output signal from said comparator circuit.