Piezo actuator comprising means for compensating thermal length modifications and fuel injection valve comprising a piezo actuator

US7514847B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Jürgen Dick · Hemau, DE
• Heinz Lixl · Regensburg, DE
• Martin Simmet · Bad Abbach, DE

Key dates

• Filing date: Jan 11, 2005
• Grant date: Apr 7, 2009
• Expiry date: Mar 28, 2026

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M2200/26
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

In an actuator unit, the piezo actuator (1) is located inside a tubular spring (3) under pre-stress. To compensate the thermal length modifications of the piezo actuator (1) in relation to the actuator housing (4, 3, 6, 5), the compensation element is configured as an aluminium compensation cylinder (2) that is situated in an extension tube (6). The piezo actuator (1) and the compensation cylinder (2) are mounted in series and conjointly pre-stressed by means of the tubular spring (3) that is extended in relation to the actuator housing by the extension tube (6).