Koda & Androlia
Engine vibration sensor
 An engine vibration sensor for detecting the engine vibration as an electric signal including a vibrator set to resonate at a specific frequency of vibration of an engine to which it is attached, the vibrator being composed of at least one piezoelectric plate and having a root and a vibrator element; means for increasing the cross-sectional area of the vibrator element to make the second moment of area of the root of the vibrator relatively larger than that of the vibrator element; a base to be connected to an engine body; and a clamp for retaining the root firmly between the clamp and the base. The clamp may be provided with a projection having a flat surface for retaining the root of the vibrator. This construction prevents a change in the effective length of the vibrator element, thereby stabilizing the characteristics of the resonant frequency of the vibrator. 
Kabushiki Kaisha Toyota Chuo Kenkyusho
G G G G
G01L G01N G01P G01H
inventional additional inventional inventional
Koji Haruyoshi Masaharu
Tsukada Kondo Takeuchi