Adjustable timing electronic internal combustion engine ignition swit system

US4127092A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Jurgen Fresow · Schwieberdingen, DE
• Bert Wurst · Asperg, DE

Key dates

• Filing date: May 11, 1977
• Grant date: Nov 28, 1978
• Expiry date: May 11, 1997

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/40
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A universally applicable system should permit easy matching of ignition timing characteristics to specific engines. In order to control a digital electronic ignition system, a marker signal is generated when a piston has reached a predetermined angular position with respect to upper dead center (UDC) position, and additional marker signals are generated as the piston moves, for example by sensing the teeth on a starwheel coupled to the engine or, for example, in an automotive engine by providing signals each time a tooth of the starter gear passes by a transducer. Two counter stages are provided which go through two count cycles for any one ignition event. The marker starts counting of both counters. The first counter stage counts for a predetermined time interval to provide a speed-dependent output number which is stored in a multiplex or memory stage, the output of which is blocked while the second counter counts. Upon the second count cycle, the second counter provides an output signal representative of an angular position with respect to UDC position, which is representative of the count state stored in the multiplex or memory circuit when deriving the speed-representative numb…