Ignition advance circuit

Claim 2

An electrical circuit for controlling the ignition advance characteristics of an internal combustion engine having a rotating crankshaft so that the ignition point advances linearly with engine speed comprising: first signal generator means including impedance means connected to a breaker device controlled by a cam being driven from said crankshaft means, connected to a base of a NPN transistor having a grounded emitter and having its collector capacitively coupled to a PNP transistor having a grounded emitter, the collector of said PNP transistor having an output U1, kx, where k is a constant and x is the angular displacement of said crankshaft beyond a reference point, whereby said output U1 comprises a series of time-separated pulses of constant peak amplitude having a leading edge the slope of which increases with engine speed and approaches a limit established by the commencement of each time-separated pulse as a fixed speed value is attained; second signal generator means including said collector of said NPN transistor being capacitively coupled to a diode bridge, said diode bridge connected to a filter having a continuous output U2 a n, where a is a constant and n is the rotational speed of the crankshaft; pulse generator means including a further NPN transistor and connected to said first and second signal generator means by said further NPN transistor having its collector connected to the collector of said PNP transistor, having its emitter connected to said filter, and having the base thereof providing an output when U1 Beta U2, where Beta is a constant, said pulse generator output being utilized to control occurrence of the ignition spark in said engine, whereby said spark is advanced with engine speed and reaches a limit of advancement as said fixed speed value is reached in said engine.

Claim 3

Method for controlling the ignition advance characteristics of an internal combustion engine having a rotating crankshaft so that the ignition point advances linearly with engine speed comprising the steps: generating by means of impedance means connected to a breaker device controlled by a cam being driven from said crankshaft in which said impedance means is connected to a base of a NPN transistor having a grounded emitter, its collector is capacitively coupled to a PNP transistor having a grounded emitter and having its collector thus producing a first signal output U1 kx, where k is a constant and x is the angular displacement of said crankshaft beyond a reference point, said first signal output U1 comprising a series of time-separated pulses of constant peak amplitude having a leading edge the slope of which increases with engine speed and approaches a limit established by the commencement of each time-separated pulse as a fixed speed value is attained; a separate step of generating by means of said collector of said NPN transistor being capactively coupled to a diode bridge in which said diode bridge is connected to a filter thus producing a continuous signal output U2 a n, where a is a constant and n is the rotational speed of the crankshaft; a further step of generating a pulse signal responsive to said first and second signal output means of a further NPN transistor having its collector connected to the collector of said PNP transistor, and in which the emitter thereof is connected to said filteR and having the base thereof providing a pulse output when U1 Beta U2, where Beta is a constant; and controlling the occurrence of the ignition spark in said engine in response to said pulse output, said spark being advanced with engine speed and reaches a limit of advancement as said fixed speed value is reached in said engine.

Claim 4

Method for controlling the ignition advance characteristics of an internal combustion engine having a rotating crankshaft so that the ignition point advances linearly with engine speed comprising the steps: generating by means of impedance means connected to a breaker device controlled by a cam being driven from said crankshaft in which said impedance means is connected to a base of a NPN transistor having a grounded emitter, its collector is capacitively coupled to a PNP transistor having a grounded emitter and having its collector thus producing a first signal output U1 kx, where k is a constant and x is the angular displacement of said crankshaft beyond a reference point, said first signal output U1 comprising a series of time-separated pulses of constant peak amplitude having a leading edge the slope of which increases with engine speed and approaches a limit established by the commencement of each time-separated pulse as a fixed speed value is attained; a separate step of generating by means of said collector of said NPN transistor being capactively coupled to a diode bridge in which said diode bridge is connected to a filter thus producing a continuous signal output U2 a n, where a is a constant and n is the rotational speed of the crankshaft; a further step of generating a pulse signal responsive to said first and second signal output means of a further NPN transistor having its collector connected to the collector of said PNP transistor, and in which the emitter thereof is connected to said filteR and having the base thereof providing a pulse output when U1 Beta U2, where Beta is a constant; and controlling the occurrence of the ignition spark in said engine in response to said pulse output, said spark being advanced with engine speed and reaches a limit of advancement as said fixed speed value is reached in said engine.