Patent ID: 9041270
Filing Date: 2015-05-26
Classification: H02N

Abstract:
1. A driving apparatus comprising: a piezoelectric element expanding and contracting in accordance with a driving pulse signal; a supporting shaft connected to said piezoelectric element; a movable body frictionally engaged with said supporting shaft and capable of moving along said supporting shaft; and a driving portion applying said driving pulse signal having a voltage value that corresponds to a driving voltage value to said piezoelectric element in order to cause relative movement of said movable body to said supporting shaft, wherein a driving voltage waveform showing a time-varying of said driving voltage value that is the same as or in a proportional relation to a voltage value of said driving pulse signal and is controlled by said driving portion has a first dropping portion where said driving voltage value sharply drops from any first value to a second value that is smaller than said first value, a second dropping portion where said driving voltage value drops from said second value to a third value that is smaller than said second value more slowly than said first dropping portion, and a third dropping portion where said driving voltage value drops from said third value to a standard value that is smaller than said third value more sharply than said second dropping portion.