by Tobias Hemsel, Jörg Wallaschek
Abstract:
Piezoelectric ultrasonic motors have been investigated for several years and have already found their first practical applications. Their key feature is that they are able to produce a high thrust force related to their volume. Beside rotary drives like the travelling wave motor, linear drives have also been developed, but only a few are presently commercially available. In the present paper, we first describe the state of the art of linear piezoelectric motors. The motors are characterized with respect to their no-load velocity, maximum thrust force, efficiency and other technical properties. In the second part, we present a new motor, which is judged to be capable of surpassing the characteristics of other piezoelectric motors because of its unique design which allows the piezoelectric drive elements to be pre-stressed in the direction of their polarization. The piezoelectric elements convert energy using the longitudinal d33 effect which allows an improved reliability, large vibration amplitudes and excellent piezoelectric coupling. Energy loss by vibration damping is minimized, and the efficiency can be improved significantly. Experimental results show that the motor characteristics can be optimized for a particular task by choosing the appropriate operating parameters such as exciting voltage, exciting frequency and normal force.
Reference:
Hemsel, T.; Wallaschek, J.: Survey of the present state of the art of piezoelectric linear motors. Ultrasonics, volume 38, 2000.
Bibtex Entry:
@ARTICLE{Hemsel2000,
author = {Tobias Hemsel and J{\"o}rg Wallaschek},
title = {Survey of the present state of the art of piezoelectric linear motors},
journal = {Ultrasonics},
year = {2000},
volume = {38},
pages = {37 - 40},
__markedentry = {[K. Agbons jr:6]},
abstract = {Piezoelectric ultrasonic motors have been investigated for several
years and have already found their first practical applications.
Their key feature is that they are able to produce a high thrust
force related to their volume. Beside rotary drives like the travelling
wave motor, linear drives have also been developed, but only a few
are presently commercially available. In the present paper, we first
describe the state of the art of linear piezoelectric motors. The
motors are characterized with respect to their no-load velocity,
maximum thrust force, efficiency and other technical properties.
In the second part, we present a new motor, which is judged to be
capable of surpassing the characteristics of other piezoelectric
motors because of its unique design which allows the piezoelectric
drive elements to be pre-stressed in the direction of their polarization.
The piezoelectric elements convert energy using the longitudinal
d33 effect which allows an improved reliability, large vibration
amplitudes and excellent piezoelectric coupling. Energy loss by vibration
damping is minimized, and the efficiency can be improved significantly.
Experimental results show that the motor characteristics can be optimized
for a particular task by choosing the appropriate operating parameters
such as exciting voltage, exciting frequency and normal force. },
bdsk-url-1 = {http://www.sciencedirect.com/science/article/pii/S0041624X99001432},
bdsk-url-2 = {http://dx.doi.org/10.1016/S0041-624X(99)00143-2},
doi = {http://dx.doi.org/10.1016/S0041-624X(99)00143-2},
issn = {0041-624X},
keywords = {Linear motor},
owner = {K. Agbons jr},
timestamp = {2013.11.23},
url = {http://www.sciencedirect.com/science/article/pii/S0041624X99001432}
}