Ignition system with ignition current and minimum spark duration controls

US4231348A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Werner Schiele · Ludwigsburg, DE
• Richard Schleupen · Großingersheim, DE

Key dates

• Filing date: Dec 27, 1978
• Grant date: Nov 4, 1980
• Expiry date: Dec 27, 1998

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B1/04
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

To prevent misfires, the current through an ignition coil is increased in response to an error signal indicating that the actual spark duration was less than a predetermined minimum spark duration. At the start of the spark, a capacitor is discharged at a known rate. The time required for the voltage across the capacitor to reach a predetermined level is the desired spark duration. This regulation of ignition current causes the spark duration to be very close to the minimum spark duration, thereby cutting losses in the apparatus.