Electronic ignition control method and apparatus

An electronic ignition control apparatus for an internal combustion engine having an output shaft rotated by a piston, an ignition coil adapted to generate a spark voltage upon deenergization of the primary winding thereof and a spark plug activated by the spark voltage to ignite the airfuel mixture metered into a combustion chamber of said engine so as to operate said piston, the control apparatus comprising:

• a first signal generator for producing a first signal at a predetermined angular interval of rotation of said output shaft;
• a second signal generator for producing a second binary signal indicative of rotation speed N of said output shaft in response to the first signal;
• a third signal generator for producing a third binary signal indicative of the amount G.sub.a of air sucked into the combustion chamber of said engine in response to the first signal;
• first memory means for storing first data indicating a first parameter f.sub.1 (G.sub.a) in relation to the amount G.sub.a of the sucked air to produce a fourth binary signal indicative of an optimum value of said first parameter f.sub.1 (G.sub.a) in accordance with the third signal, said first parameter defining an ascent of a linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), approximately representing a relationship between an optimum advance angle .theta. for activation of said spark plug and the rotation speed N of said output shaft in consideration with the amount G.sub.a of the sucked air;
• second memory means for storing second data indicating a second parameter f.sub.2 (G.sub.a) in relation to the amount G.sub.a of the sucked air to produce a fifth binary signal indicative of an optimum value of said second parameter f.sub.2 (G.sub.a) in accordance with the third binary signal, said second parameter defining an ordinates' intersection of the linear equation, .theta.=f.sub.1 (G.sub.a).multidot.N+f.sub.2 (G.sub.a), in consideration with the amount G.sub.a of the sucked air;
• a calculation circuit for calculating the linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), in accordance with the second, fourth and fifth binary signals to obtain the optimum advance angle .theta. in relation to the rotation speed N of said output shaft;
• and
• a timing signal generator for generating a timing signal in accordance with the optimum advance angle .theta. such that the primary winding of said ignition coil is deenergized in response to the timing signal.

An electronic ignition control method for an internal combustion engine having an output shaft rotated by a piston, an ignition coil adapted to generate a spark voltage upon deenergization of the primary winding thereof and a spark plug activated by the spark voltage to ignite the air-fuel mixture metered into a combustion chamber of said engine so as to operate said piston, the method comprising the steps of:

• automatically producing a first signal at a predetermined angular interval of rotation of said output shaft;
• automatically producing a second binary signal indicative of rotation speed N of said output shaft in response to the first signal;
• automatically producing a third binary signal indicative of the amount G.sub.a of air sucked into the combustion chamber of said engine in response to the first signal;
• reading out first data preliminarily stored in a memory indicating a first parameter f.sub.1 (N) in relation to the rotation speed N of said output shaft to automatically produce a fourth binary signal indicative of an optimum value of said first parameter f.sub.1 (N) in accordance with the second binary signal, said first parameter defining an ascent of a linear equation, .theta.=-f.sub.1 (N)G.sub.a +f.sub.2 (N), representing a relationship between an optimum advance angle .theta. for activation of said spark plug and the amount G.sub.a of the sucked air in consideration with the rotation speed N of said output shaft;
• reading out second data preliminarily stored in a memory indicating a second parameter f.sub.2 (N) in relation to the rotation speed N of said output shaft to automatically produce a fifth binary signal indicative of an optimum value of said second parameter f.sub.2 (N) in accordance with the second binary signal, said second parameter defining an ordinates' intersection of the linear equation, .theta.=-f.sub.1 (N).multidot.G.sub.a +f.sub.2 (N), in consideration with the rotation speed N of said output shaft;
• automatically calculating the linear equation, .theta.=-f.sub.1 (N)G.sub.a +f.sub.2 (N), in accordance with the third, fourth and fifth binary signals to obtain the optimum advance angle .theta. in relation to the amount G.sub.a of air;
• and
• automatically generating a timing signal in accordance with the optimum advance angle .theta. such that the primary winding of said ignition coil is deenergized in response to the timing signal.

An electronic ignition control method for an internal combustion engine having an output shaft rotated by a piston, an ignition coil adapted to generate a spark voltage upon deenergization of the primary winding thereof and a spark plug activated by the spark voltage to ignite the air-fuel mixture metered into a combustion chamber of said engine so as to operate said piston, the method comprising the steps of:

• automatically producing a first signal at a predetermined angular interval of rotation of said output shaft;
• automatically producing a second binary signal indicative of rotation speed N of said output shaft in response to the first signal;
• automatically producing a third binary signal indicative of the amount G.sub.a of air sucked into the combustion chamber of said engine in response to the first signal;
• reading out first data preliminarily stored in a memory indicating a first parameter f.sub.1 (G.sub.a) in relation to the amount G.sub.a of the sucked air to automatically produce a fourth binary signal indicative of an optimum value of said first parameter f.sub.1 (G.sub.a) in accordance with the third signal, said first parameter defining an ascent of a linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), approximately representing a relationship between an optimum advance angle .theta. for activation of said spark plug and the rotation speed N of said output shaft in consideration with the amount G.sub.a of the sucked air;
• reading out second data preliminarily stored in a memory indicating a second parameter f.sub.2 (G.sub.a) in relation to the amount G.sub.a of the sucked air to automatically produce a fifth binary signal indicative of an optimum value of said second parameter f.sub.2 (G.sub.a) in accordance with the third binary signal, said second parameter defining an ordinates' intersection of the linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), in consideration with the amount G.sub.a of the sucked air;
• automatically calculating the linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), in accordance with the second, fourth and fifth binary signals to obtain the optimum advance angle .theta. in relation to the rotation speed N of said output shaft;
• and
• automatically generating a timing signal in accordance with the optimum advance angle .theta. such that the primary winding of said ignition coil is deenergized in response to the timing signal.

An electronic ignition control apparatus for an internal combustion engine having an output shaft rotated by a piston, an ignition coil adapted to generate a spark voltage upon deenergization of the primary winding thereof and a spark plug activated by the spark voltage to ignite the air-fuel mixture metered into a combustion chamber of said engine so as to operate said piston, the control apparatus comprising:

• a first signal generator for producing a first binary signal indicative of rotation speed N of said output shaft;
• a second signal generator for producing a second binary signal indicative of an amount G.sub.a of air sucked into the combustion chamber of said engine;
• first memory means for storing first data indicating a first parameter f.sub.1 (N) in relation to the rotation speed N of said output shaft to produce a third binary signal indicative of an optimum value of said first parameter f.sub.1 (N) in accordance with the first binary signal, said first parameter defining an ascent of a linear equation, .theta.=-f.sub.1 (N).multidot.G.sub.a +f.sub.2 (N), representing a relationship between an optimum advance angle .theta. for activation of said spark plug and the amount G.sub.a of the sucked air in consideration with the rotation speed N of said output shaft;
• second memory means for storing second data indicating a second parameter f.sub.2 (N) in relation to the rotation speed N of said output shaft to produce a fourth binary signal indicative of an optimum value of said second parameter f.sub.2 (N) in accordance with the first binary signal, said second parameter defining an ordinates' intersection of the linear equation, .theta.=-f.sub.1 (N).multidot.G.sub.a +f.sub.2 (N), in consideration with the rotation speed N of said output shaft;
• a calculation circuit for calculating the linear equation, .theta.=-f.sub.1 (N).multidot.G.sub.a +f.sub.2 (N), in accordance with the second, third and fourth binary signals to obtain the optimum advance angle .theta. in relation to the amount G.sub.a of air;
• and
• a timing signal generator for generating a timing signal in accordance with the optimum advance angle .theta. such that the primary winding of said ignition coil is deenergized in response to the timing signal.

An electronic ignition control apparatus for an internal combustion engine having an output shaft rotated by a piston, an ignition coil adapted to generate a spark voltage upon deenergization of the primary winding thereof and a spark plug activated by the spark voltage to ignite the air-fuel mixture metered into a combustion chamber of said engine so as to operate said piston, the control apparatus comprising:

• a first signal generator for producing a first binary signal indicative of rotation speed N of said output shaft;
• a second signal generator for producing a second binary signal indicative of the amount G.sub.a of air sucked into the combustion chamber of said engine;
• first memory means for storing first data indicating a first parameter f.sub.1 (G.sub.a) in relation to the amount G.sub.a of the sucked air to produce a third binary signal indicative of an optimum value of said first parameter f.sub.1 (G.sub.a) in accordance with the second signal, said first parameter defining an ascent of a linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), approximately representing a relationship between an optimum advance angle .theta. for activation of said spark plug and the rotation speed N of said output shaft in consideration with the amount G.sub.a of the sucked air;
• second memory means for storing second data indicating a second parameter f.sub.2 (G.sub.a) in relation to the amount G.sub.a of the sucked air to produce a fourth binary signal indicative of an optimum value of said second parameter f.sub.2 (G.sub.a) in accordance with the second binary signal, said second parameter defining an ordinates' intersection of the linear equation, .theta.=f.sub.1 (G.sub.a).multidot.N+f.sub.2 (G.sub.a), in consideration with the amount G.sub.a of the sucked air;
• a calculation circuit for calculating the linear equation, .theta.=f.sub.1 (G.sub.a)N+f.sub.2 (G.sub.a), in accordance with the first, third and fourth binary signals to obtain the optimum angle .theta. in relation to the rotation speed N of said output shaft;
• and
• a timing signal generator for generating a timing signal in accordance with the optimum advance angle .theta. such that the primary winding of said ignition coil is deenergized in response to the timing signal.