| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a driving gear switching a driving method in accordance with a controlled speed and an adjusted condition of a moving member which desires a plurality of the driving methods. <P>SOLUTION: This driving gear comprises a piezoelectric element 26 extended/ contracted by applying drive voltage, a support member 24 secured to one end in an extended/contracted direction of the piezoelectric element 26, a driving member 28 secured to the other end in the extended/contracted direction of the piezoelectric element 26, a moving member 30 engaged by prescribed frictional force with the driving member 28 to make relative movement to the support member 24 by extending/contracting the piezoelectric element 26 at a different speed, a driving circuit 14 generating the drive voltage, and a control unit 22 controlling a driving circuit 14 by switching a second driving method using a plurality of drive signals of different frequency and a first driving method using a drive signal of duty ratio D not a level amounting to 0.5. <P>COPYRIGHT: (C)2004,JPO |
