Patent ID: 8887582

Claim:
A piezoelectric vibration type force sensor, comprising: a vibration body including a ring-shaped piezoelectric material having a hollow through hole and a pair of drive electrodes attached to both sides of the piezoelectric material, for vibrating in a spreading direction of the piezoelectric material when an AC voltage is applied to the pair of drive electrodes; a substrate to be brought into contact with a surface on one side of the vibration body; an elastic member that is disposed to be brought into contact with a surface on another side of the vibration body, for transmitting a force applied externally to the vibration body by elastic deformation; a holding portion including a contact portion that is larger than the hollow through hole and that does not protrude from an outer circumferential portion of the vibration body so as to be brought into contact with the surface on the another side of the vibration body, and a loose-fit portion that loosely fits in the hollow through hole, the loose-fit portion being fastened to the substrate; and a pair of signal electrodes for applying the AC voltage to the pair of drive electrodes.