Piezoelectric drive for fuel-injector valve, has axial bore hole provided in housing and extending over portion of piezoelectric actuator and evaporation region of closed chamber, which contains cooling medium e.g. propanol

摘要

The drive has a piezoelectric actuator (2) and a housing (3) enclosing a cylindrical surface of the actuator. A closed chamber contains a cooling medium e.g. propanol, which is evaporated due to the heat output by the actuator and is condensed at evaporation and condensing regions, respectively of the chamber. An axial bore hole (6) provided in the housing extends over a portion of the actuator and the evaporation region.