Common rail injector

US6726121B1 · kind B1 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Dieter Kienzler · Leonberg, DE
• Patrick Mattes · Stuttgart, DE
• Wolfgang Stoecklein · Stuttgart, DE
• Friedrich Boecking · Stuttgart, DE

Key dates

• Filing date: Aug 20, 2001
• Grant date: Apr 27, 2004
• Expiry date: Jun 26, 2022

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M2547/003
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, which system has an injector housing (1) with a fuel inlet (24) that is in communication with a central high-pressure fuel reservoir outside the injector housing (1) and with a pressure chamber (27) inside the injector housing (1), from which fuel subjected to high pressure is injected as a function of the position of a control valve (18) that assures that a nozzle needle (8), which is movable back and forth and received in a longitudinal bore (6) of the injector axially counter to the prestressing force of a nozzle spring (21) that is received in a nozzle spring chamber (20), lifts from a seat when the pressure in the pressure chamber (27) is greater than the pressure in a control chamber (30) that communicates with the fuel inlet (24) via an inlet throttle (19).To achieve markedly higher nozzle needle speeds, the control chamber (15) is formed by a cylindrical chamber, in which a control peg (12), embodied on the end of the nozzle needle (8) remote from the combustion chamber, is displaceable causing a sealing effect, and that the nozzle spring ch…