| 摘要 |
PROBLEM TO BE SOLVED: To detect changes in an amount of a lubrication oil and the deterioration degree of the lubrication oil in a vibration actuator early.SOLUTION: A vibration actuator includes: a stator 13 which generates vibrations; a rotor 30 which makes pressure contact with the stator 13 and is rotated by the vibrations of the stator 13; a sponge body 80 which is impregnated with a lubrication oil and is disposed contacting with the rotor 30 so as to supply the lubrication oil to contact surfaces of the rotor 30 and the stator 13; and a color sensor 90 which detects color change of the sponge body 80 thereby detecting changes in an amount of the lubrication oil contained in the sponge body 80 and the deterioration degree of the lubrication oil. |
