Accelerometer for IC engine knock vibration detection - has piezo-ceramic plate loaded via seismic mass with pre-stressing arrangement

摘要

An accelerometer contg. a piezoceramic plate (1), a seismic mass (2) and a piezoceramic plate stressing arrangement (5,6,8) can be used to detect the vibrations associated with knock in an internal combustion engine. The seismic mass (2) and the piezoceramic plate stressing components (5,6,8) are tuned to the frequency of the knock vibrations. The piezoceramic plate is loaded via the seismic mass, to which an insulating plate (4) is stuck. The seismic plate is loaded via a steel plate (5) with the force exerted by a plate spring (6). The steel plate protects the insulating plate from excessive surface pressure and eventually against wear. The piezoceramic plate is held in position by a locating disc (7).