Electromagnetic valve-controlled fuel injection pump for internal combustion engines, especially diesel engines

US6884041B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Peter Boehland · Erbach, DE
• Andreas Sterr · Leverkusen, DE
• Andreas Dutt · Stuttgart, DE

Key dates

• Filing date: Nov 16, 2001
• Grant date: Apr 26, 2005
• Expiry date: Mar 8, 2022

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M59/366
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A solenoid-valve-controlled fuel-injection pump for internal combustion engines, in particular diesel engines, has a solenoid valve, whose valve needle separates a high-pressure region from a low-pressure region, i.e. connects the high-pressure region and low-pressure region, in the pump housing, via a valve seat; the injection period being controlled by the opening of the solenoid valve. In addition, a low-pressure compensating piston situated in the low-pressure region is provided in order to compensate for pressure fluctuations in the low-pressure region. The exceptional feature is that the low-pressure compensating piston, which is positioned coaxially to the solenoid-valve needle, takes the form of a component part that is separate from the solenoid-valve needle. This ensures that the solenoid valve is opened unhindered and as rapidly as possible by the opening force exerted on the solenoid-valve needle by the electromagnet.