Method for starting an internal combustion engine, particularly an internal combustion engine having direct fuel injection

US6918367B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Helmut Denz · Stuttgart, DE
• Andreas Kufferath · Besigheim, DE
• Martin Ludwig · Wuppertal, DE

Key dates

• Filing date: Jan 12, 2004
• Grant date: Jul 19, 2005
• Expiry date: Jan 12, 2024

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2250/31
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

During a start, particularly during a cold start, of an internal combustion engine without additional auxiliary drive, a precisely metered fuel mass is introduced into a combustion chamber. In the case of an internal combustion engine having direct fuel injection, a rail pressure prevailing in a high-pressure accumulator is frequently only insufficiently built up during a start, which has an unfavorable effect on the mixture formation. To improve the start performance of the internal combustion engine, the injection pressure available in the high-pressure accumulator is monitored during the start, and fuel from the high-pressure accumulator is first injected into the at least one combustion chamber when the injection pressure has reached or exceeded a specifiable threshold value. This ensures that the rail pressure is high enough, in order to inject a sufficient quantity of fuel into the combustion chamber so that an ignitable air/fuel mixture is formed.