| 摘要 |
PURPOSE:To obtain a machining accuracy by enabling machining of a vibrating body to be in a plane shape for simplification by providing a recessed part on a surface which is partially in contact with a traveling body for a width of the vibrating body. CONSTITUTION:A first elastic body 1 constitutes a torus-shaped vibrating body 3 along with a piezoelectric body 2 and a recessed part 4 is provided at the inside which does not reach an outer diameter in a width of a plane of the tours-shaped vibrating body 3. A vibrating body 5 is in contact with this vibrating body 3 through a friction material 8 by pressing. The amount of displacement of a vibration displacement in the radial direction of the torus- shaped plate vibrating body 3 becomes larger toward the outside since a primary vibration mode is in use. However, since mechanical rigidity changes in proportion to a power of three of the plate thickness by providing the recessed part 4 at the inside, the amount of displacement can be flattened in the radial direction so that a stable contact can be achieved even when the center is shifted due to poor accuracy of shaft. Also, since the traveling body is driven at the inside where the amplitude of the vibration body 3 is small, stable property against fluctuation of load can be achieved. |
