Semiconductor ignition system for internal combustion engines

US4100908A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Reinhard Leussink · Leinfelden, DE
• Walter Ruf · Ditzingen, DE

Key dates

• Filing date: Jul 21, 1976
• Grant date: Jul 18, 1978
• Expiry date: Jul 21, 1996

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02P3/0556
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

To provide for gradual decay of current flow through the primary of an ignition coil, and hence suppression of spurious sparks at spark plugs, a main switching transistor has its conductivity controlled by the conductivity of the emitter-collector path of a control transistor, the base-emitter path of which forms part of a discharge circuit of a control capacitor, which discharge circuit has a sufficiently high resistance to provide for gradual discharge of the capacitor and hence gradual transition of the conductivity of the control transistor.