Engine knock vibration sensor with adjustable resonant frequency - has adjustable spring acting on seismic mass influencing sensor

摘要

A seismic mass (14) acts upon a transducer element (12) converting force into an electrical voltage. The resonant frequency is adjusted by varying the effect of an adjustable spring (15) acting in the mass (14) or by the removal of material from the mass. The sensor is attached to the engine casing via a bolt (10) attached directly to its housing (11). The spring (15) is adjusted by using a screw (16) passing through the housing. The spring enables both negative and positive accelerations acting on the sensor to be detected.