Fuel injection nozzle for internal combustion engines

US4909446A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Ewald Eblen · Stuttgart, DE
• Rolf J. Giersch · Eberdingen, DE
• Karl Hofmann · Neckarrems, DE

Key dates

• Filing date: Aug 17, 1988
• Grant date: Mar 20, 1990
• Expiry date: Aug 17, 2008

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M61/06
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

Fuel injection nozzle for internal combustion engines comprising an inwardly opening valve needle (14) and a nozzle bore hole (20) into which a throttle pivot (18) of the valve needle (14) dips during an initial lift. The throttle pivot (18) is provided with at least two flattened portions (30, 32 and 30, 32, 40, respectively) for forming preferred pass-through cross sections in the nozzle bore hole (20), wherein at least two flattened portions (30, 32 and 32, 40, respectively) end in different cross-sectional planes of the throttle pivot (18). Accordingly, a stepwise enlargement of the total cross section in the nozzle bore hole (20) can be achieved during the initial lift of the valve needle (14) with manufacturing methods which can be controlled in a favorable manner.