Koda and Androlia
Stress detector
 A stress detector including an AC power source for generating an AC symmetrical wave form voltage, an exciting coil driven by the AC power source for alternatingly magnetizing at least a portion of a ferromagnetic material to be measured in a predetermined direction, a detecting coil for detecting a magnetic flux generated due to the alternating magnetization, and an adder circuit for taking out a part of a voltage applied to the exciting coil, setting an amplitude and a phase of a wave form of the taken-out part of the voltage to preset values, adding the voltage thus obtained to a voltage induced in the detecting coil. The detector gives an output signal representative of a value of stress applied to the material to be measured as a variation either in amplitude or phase depending on the preset phase. 
Kabushiki Kaisha Toyota Chuo Kenkyusho
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inventional inventional inventional inventional
Jun Yutaka Hirofumi Masaharu
Sugiyama Nonomura Komatsubara Takeuchi