Fuel-injection valve

US7500648B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Werner Kammerer · Leinfelden, DE
• Klaus Noller · Oppenweiler, DE
• Hubert Stier · Asperg, DE
• Dietmar Schmieder · Markgröningen, DE
• Michael Huebel · Gerlingen, DE
• Thomas Gerschwitz · Lambach, DE
• Christian Leitner · Summerau, AT

Key dates

• Filing date: Feb 14, 2004
• Grant date: Mar 10, 2009
• Expiry date: Dec 15, 2024

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M51/0603
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A fuel injector has a piezoelectric or magnetostrictive actuator, which actuates a valve-closure member cooperating with a valve-seat surface a sealing seat. An hydraulic coupler includes a master piston, a slave piston, and a coupler volume formed in-between, the coupler volume being connected to a compensating chamber via a throttle. An elastic flexible section delimits the compensating chamber at least partially, and the coupler volume, the throttle, and the compensating chamber are filled with an hydraulic medium. The flexible section exerts a pressure on the hydraulic medium due to prestressing, and the force of a compression spring, which is braced either directly and/or via fixed components on the slave piston and the master piston, is directed with an initial stress in such a way that the force enlarges the coupler volume.