| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonic motor which can be controlled with accuracy by detecting the quantity of rotation of the rotor and also is downsized more. SOLUTION: A slit body 31 is attached to a rotor 15 rotating by a piezoelectric element 11. Moreover, a spring sheet 20 to support, from outside, a leaf spring 16 to push the rotor 15 against the side of the piezoelectric element 11 is provided with a recess 23. A light emitting part 32 is attached onto this recess 23 and a light receiving part 33 to the bottom. Moreover, the slit body 31 enters this recess 23. Accordingly, the detection of the quantity of rotation of the rotor 15 is possible without providing its outside with,new parts, and besides an ultrasonic motor, which has become smaller by using the leaf spring 16, can be manufactured. |
