Injection pump having cold start acceleration for direct injection internal combustion engines

US6792922B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Helmut Simon · Göppingen, DE
• Helmut Haberer · Gerlingen, DE

Key dates

• Filing date: Nov 15, 2002
• Grant date: Sep 21, 2004
• Expiry date: Nov 15, 2022

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D2001/186
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A fuel delivery unit for an internal combustion engine including a housing, which includes a timing unit for shifting the point of injection of fuel into the combustion chambers of the internal combustion engine. An injection timing piston is accommodated in the timing unit, which is displaceably mounted in the timing unit and which encloses a trailing piston displaceably relative thereto. The timing unit contains a pressure chamber which may be pressurized/depressurized via an actuator, a cold start accelerator piston being movable via the pressure chamber, acting upon both the trailing piston via a spring element and, together with a spring-sleeve combination, influencing the injection timing piston.