METHOD FOR PRODUCING A TUBULAR SPRING

摘要

A method for producing a tubular spring ( 12 ) in the form of a cylindrical hollow body, especially for pre-tensioning a piezoelectric actuator element ( 2 ) of an actuator unit ( 1 ) of a fuel injector comprises the step of providing a thin-walled, solid-drawn steel tube with a plurality of regularly arranged longish recesses ( 14 ) by means of laser cutting. Thus, an actuator unit ( 1 ) comprises a piezoelectric actuator element ( 2 ) which is arranged in a thin-walled cylindrical hollow body, wherein the hollow body being elastically embodied and pre-tensioning the actuator element ( 2 ). Furthermore, the hollow body is a solid-drawn steel tube which is provided with a plurality of longish recesses ( 14 ).