Safety design fuel injector especially for self igniting IC engines has the electric contacts to the piezo module shunted via a controlled conductor

摘要

A safety design fuel injector, especially for a self igniting IC engine, has the electric contacts (21, 23) to the piezo module shunted via a controlled conductor (30) which does not affect the transmission of short time pulses, e.g. for the normal operation of the piezo module. In the event of an interruption in the electric supply to the piezo module the safety conductor progressively shorts the contacts and ensures that the piezo module is in the contacted settings, i.e. with the injector valve shut. The controlled conductor comprises a thin film conductor on an insulating substrate and is easily incorporated into conventional piezo modules.