Means and method for controlling the occurrence and the duration of time

Abstract

A control system controls the occurrence and duration of time intervals during which sparks may be provided in the cylinders of an internal combustion engine driving a crankshaft as a function of loading parameters on the engine. In an automotive engine control system, parameters such as the vacuum in the carburetor, the throttle setting and the torque of the crankshaft are sensed and corresponding signals are provided by the sensors. A first pulse signal is provided. The pulses in the first pulse signal correspond to the rotational speed of the crankshaft. The distributor provides a second pulse signal. Each pulse in the second pulse signal has a width corresponding to a predetermined rotational displacement of the crankshaft and has a relationship to the position of a piston in a corresponding cylinder. A circuit shapes the pulses of the second pulse signal and provides them to a network which provides a start pulse in accordance with the shaped pulses and the first pulse signal. A preload circuit preloads a counter in the start pulse network in accordance with the sensed parameter signals and the first pulse signal to control the occurrence of the start pulses. A second network provides a stop signal in accordance with the first pulse signal and a spark time interval pulse signal. A pulse circuit receiving the spark pulses and the stop signal provides the spark time interval pulse signal to the ignition system and to the stop signal network so that the stop signal network controls the duration of each pulse in the spark time interval pulse signal. The ignition system provides sparks in the engine in a predetermined manner during the occurence of a pulse in the spark time interval pulse signal.