GB1284510A - Acceleration enrichment circuit for electronic fuel control systems - Google Patents

Abstract

1284510 Fuel injection systems BENDIX CORP 15 Jan 1971 [17 Feb 1970] 2135/71 Heading G1N In an I. C. engine fuel injection control system fuel enrichment is provided during acceleration by a series of opening pulses applied to the injectors in addition to the main opening pulses. As shown, selected injectors are energized when a transistor 20 is conductive. Each main opening pulse is composed of two pulses, a first of which is provided by a multivibrator 28, 30 at a frequency dependent upon engine speed and having a duration dependent upon intake pressure (sensor 12). The second pulse occurs immediately after the first and has a duration dependent upon engine temperature (sensor 14). The two pulses are applied via resistors 22, 24 respectively to render transistor 20 conductive. Upon sensing a need for acceleration at 82, Fig.2, e.g. by a switch connecting point 82 to ground, the voltage jump on the collector of transistor 84 is applied to point C for a duration dependent upon the limiting voltage set by Zener diode 88. The pulse at point C renders transistor 20 conductive and thus causes additional fuel to be supplied by the most recently actuated injectors. Also the sensed need for acceleration at point 82 allows the trailing edge of the second pulse received at point B to render a transistor 94 non- conductive for a period determined by the charging of capacitors 98, the resulting pulse on the collector of transistor 94 rendering transistor 20 conductive thereby increasing the amount of fuel. The sequence of pulses produced by transistor 94 lasts for as long as the sensed need for accleration lasts.