Fuel injection pump for internal combustion engines

US4975030A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Gunter Bofinger · Leinfelden, DE
• Claus Maier · Ludwigsburg, DE
• Gerhard Reichan · Stuttgart, DE

Key dates

• Filing date: Apr 21, 1989
• Grant date: Dec 4, 1990
• Expiry date: Apr 21, 2009

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M41/126
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A fuel injection pump for internal combustion engines comprising a pump plunger displaceable in a pump cylinder for delivering fuel to a plurality of injection locations, and elements for controlling fuel injection quantity. The controlling elements include a relief channel in the pump plunger for communicating a pump working space defined by the pump plunger with a relief chamber, an outlet port on an outer surface of the pump plunger for communicating the relief channel with the relief chamber, at least two connecting cross-sections of different shape for communicating the relief chamber with the outer port, and a slide valve displaceable along the outer surface of the plunger and having a control edge for controlling flow of fuel through the connecting cross-sections during a delivery stroke of the pump plunger.