Piezo-actuator for use as part of injector for common rail diesel fuel injection system, has air gap between outer side of spring and inner wall of housing, and punched and/or curved sheet metal heat guiding plate arranged in air gap

摘要

The piezo-actuator (1) has a tubular housing (4) with two ends, an external wall (5) directed outwards and an inner wall (6) directed inwards. A head plate (7) closes one of the two ends of the tubular housing. A tubular spring (28) is arranged within the tubular housing and fixed at the head plate. A spring is designed such that an air gap is formed between the outer side of the spring and the inner wall of the housing. Punched and/or curved sheet metal heat guiding plate is arranged in the air gap for providing direct heat transmission between the spring and the housing.