Mitsubishi Denki Kabushiki Kaisha

Fuji Ceramics Corporation

Hidehiro Inaba

Harumasa Shibata

Akito Yokoi

Keizo Miyake

A knock sensor of the invention includes a base having a cylindrical part mounted on a vibration generating part and a flange part, an annular piezoelectric element fitted to the cylindrical part and for converting a knocking vibration of the vibration generating part into an electric signal to detect it, electrodes respectively provided to be in contact with both surfaces of the piezoelectric element, terminal plates disposed to be in contact with the respective electrodes and for extracting an output of the piezoelectric element to outside, and a hold unit for pressure holding the piezoelectric element, the electrodes and the terminal plates to the flange part, in which a conductive adhesive material having an almost equal thickness to the electrode is provided on a portion of the piezoelectric element which is not in contact with the electrode.

Knock sensor

A knock sensor of the invention includes a base having a cylindrical part mounted on a vibration generating part and a flange part, an annular piezoelectric element fitted to the cylindrical part and for converting a knocking vibration of the vibration generating part into an electric signal to detect it, electrodes respectively provided to be in contact with both surfaces of the piezoelectric element, terminal plates disposed to be in contact with the respective electrodes and for extracting an output of the piezoelectric element to outside, and a hold unit for pressure holding the piezoelectric element, the electrodes and the terminal plates to the flange part, in which the electrodes are provided to be in partial contact with the piezoelectric element, and an electric insulating material having an almost equal thickness to the electrode is provided on a portion of the piezoelectric element which is not in contact with the electrode.

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Shizuoka, Japan

Hidehiro Inaba