Engine control systems

Claim 2

An engine control system for an engine in which an operating function of the engine is controlled by the length of an electric pulse applied to the engine, comprising in combination a first transducer producing a first signal representative of a first engine parameter, a second transducer producing a second signal representative of another engine parameter, a programmed logic circuit means, to which said signals are fed, said logic circuit means producing an output dependent on the values of said first and second signals, a controllable output circuit means for normally producing an output pulse having a predetermined length in the absence of an output signal from said logic circuit means, said output pulse controlling said operating function of the engine, means controlled by the engine for initiating each output pulse, and means coupling said logic circuit means to the output stage, such that the length of said output pulse is increased in accordance with and upon the occurrence of said output signal from said logic circuit means.

Claim 3

An engine control system as claimed in claim 1 wherein the output from said logic means is digital, the system further including a comparator, means coupling the logic circuit means to the comparator, a second increasing digital signal being applied to the comparator after the first predetermined period of time by said logic means, and the comparator producing an output when the second digital signal becomes equal to the first digital signal, the output pulse being terminated when the comparator has produced at least one output signal.

Claim 4

An engine control system as claimed in claim 2 including scanning means coupling the comparator to the storage memory unit so that said comparator scans the output from said logic means n times, where n is greater than 1, and terminates the output pulse only after n scannings.

Claim 5

An engine control system as claimed in claim 1 in which said scanning means includes means for varying the signals applied to said logic means by small increments so that for a given value of each engine parameter, n outputs are produced cyclically by said logic means, these n outputs being scanned in turn before the output pulse is terminated.

Claim 6

An engine control system as claimed in claim 2 including a counter providing the required second input to said comparator, a clock pulse generator providing an input to said counter, and a dividing network incorporated between the clock pulse generator and the counter to provide the predetermined period of time before the output from said logic means is scanned.

Claim 7

An engine control system as claimed in claim 5 wherein means is provided for varying the frequency of the clock pulse generator in accordance with a further engine parameter, so as to vary the length of the output pulse in accordance with said further engine parameter.

Claim 8

An engine control system for an engine in which an operating function of the engine is controlled by the length of an electric pulse applied to the engine, comprising in combination a first transducer producing a first signal representative of a first engine parameter, a second transducer producing a second signal representative of another engine parameter, a Programmed logic circuit means to which said signals are applied, said said logic circuit means producing a digital output dependent on the values of said first and second signals, a digital register to which the output from said logic means is fed, an output circuit means for initiating commencement of an output pulse used to control said operating function of the engine, and for terminating said output pulse when the digital register has produced n outputs, where n is at least 2, counting means coupled to said digital register, said counting means serving when operative to scan the output of the register n times, each scanning causing the digital register to produce an output after a period of time dependent on the value of the signal fed to the digital register by said logic means, and means coupling said counting means to said output circuit means whereby said output circuit means initiates operation of said counting means at the same time that an output pulse is initiated.

Claim 9

An engine control system for an engine in which an operating function of the engine is controlled by the length of an electric pulse applied to the engine, comprising in combination a first transducer producing a first signal representative of a first engine parameter, a second transducer producing a second signal representative of another engine parameter, a Programmed logic circuit means to which said signals are applied, said said logic circuit means producing a digital output dependent on the values of said first and second signals, a digital register to which the output from said logic means is fed, an output circuit means for initiating commencement of an output pulse used to control said operating function of the engine, and for terminating said output pulse when the digital register has produced n outputs, where n is at least 2, counting means coupled to said digital register, said counting means serving when operative to scan the output of the register n times, each scanning causing the digital register to produce an output after a period of time dependent on the value of the signal fed to the digital register by said logic means, and means coupling said counting means to said output circuit means whereby said output circuit means initiates operation of said counting means at the same time that an output pulse is initiated.

Claim 10

An engine control system as claimed in claim 7 including means for varying the signals applied to said logic means by small increments so that for a given value of each parameter, n outputs are produced cyclically by said logic means, these n outputs being scanning in turn before the output pulse is terminated.

Claim 11

An engine control system as claimed in claim 7 wherein the digital register is a comparator which receives a digital input from said logic means and an increasing signal from the counting means, and produces an output when the signals are equal.

Claim 12

An engine control system for an engine in which an operating function of the engine is controlled by the length of an electric pulse applied to the engine, comprising in combination a first transducer producing a first signal representative of a first engine parameter, a second transducer producing a second signal representative of another parameter, a programmed logic circuit means to which said signals are fed, said logic circuit means producing a digital output dependent on the values of said first and second signals, a digital register to which the output from said logic means is fed, an output circuit means for initiating an output pulse used to control said operating function of the engine, and for terminating said output pulse when the digital register has produced at least one output, a pulse generator coupled to said digital register, said pulse generator serving when operative to scan the output of the register and cause the register to produce an output after a period of time dependent on the value of the signal fed to the digital register by said logic means, means coupling said pulse generator to said output circuit means whereby said pulse generator is rendered operative when an output pulse is initiated by said output circuit means, and means for changing the frequency of the pulse generator in accordance with a further parameter.

Claim 13

An engine control system for an engine in which an operating function of the engine is controlled by the length of an electric pulse applied to the engine, comprising in combination a first transducer producing a first signal representative of a first engine parameter, a second transducer producing a second signal representative of another parameter, a programmed logic circuit means to which said signals are fed, said logic circuit means producing a digital output dependent on the values of said first and second signals, a digital register to which the output from said logic means is fed, an output circuit means for initiating an output pulse used to control said operating function of the engine, and for terminating said output pulse when the digital register has produced at least one output, a pulse generator coupled to said digital register, said pulse generator serving when operative to scan the output of the register and cause the register to produce an output after a period of time dependent on the value of the signal fed to the digital register by said logic means, means coupling said pulse generator to said output circuit means whereby said pulse generator is rendered operative when an output pulse is initiated by said output circuit means, and means for changing the frequency of the pulse generator in accordance with a further parameter.

Claim 14

An engine control system as claimed in claim 10 including means for varying the frequency of the pulse generator in accordance with three parameters, the pulse generator including a capacitor which is charged by a transistor, the base voltage of which is determined by one of the said parameters and the collector current of which is determined, for a given base voltage, by another of said parameters, and a thyristor the cathode potential of which is determined by the charge on the capacitor and the gate potential of which is determined by the third of said parameters, the capacitor charging through the transistor until the thyristor turns on, and then discharging through the thyristor after which the cycle is repeated.