Dwell period control for engine ignition

US4467776A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Manfred Mezger · Markgröningen, DE
• Georg Pfaff · Schifferstadt, DE
• Karl Seeger · Ditzingen, DE

Key dates

• Filing date: Jul 15, 1982
• Grant date: Aug 28, 1984
• Expiry date: Jul 15, 2002

Classification

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

Abstract

A countdown counter (14) counts out a speed dependent number to determine the start of the dwell period when a comparison number (Z17) is reached which is adjusted dynamically by a regulation counter (17). The countdown counter's contents are reduced by a value dependent upon acceleration when acceleration is present in order to improve the dynamic correction. In the case of strong accelerations these dynamic corrections are insufficient and when such a strong acceleration occurs the regulation counter content is set to a high value to assure a succession of strong ignition sparks. The high value of acceleration necessary for this precaution may be determined by comparing the difference of successive engine speed counts with a predetermined value or it may be determined by the failure of the current in the ignition coil primary to reach some predetermined value. After the generation of strong sparks is thus assured, the comparison count value provided by the regulation counter gradually returns to normal by the operation of the provisions for normal accommodation to dynamic conditions.