what is piezoelectric actuators?

Answer 1

Piezoelectric devices (piezo, for short) are ceramic or crystal materials that deform when an electric signal is applied to them. Some also work the opposite way: they generate an electrical signal when they are deformed. The deformation can be almost any mechanical movement. Pressure, bending, twisting, can cause a piezo device to generate a signal proportional to the amount of pressure, etc, that is applied.

A piezo sound generator will vibrate at the same mechanical rate as the electrical signal applied to it. They are used for earphones and tweeter (high frequency speakers.) (Most tiny in-the-ear earphones are made with piezo materials.)

Some piezo devices are microscopically small. In some projectionTV systems, there is a laser that is deflected by tiny piezo devices to reflect at different points on the screen. This happens so rapidly, you are not able to follow the spot, and it appears to be a continuous beam. They use a separate beam for the three primary colors of light, and presto! You have a color TV picture on the screen.

Piezo devices are used to create little electric sparks, in cigarette lighters, to ignite the butane gas. Youpress down the lever, a spring snaps against the piezo device, and the electric charge is led out by means of a fine wire to the jet where the gas is allowed to escape, and it ignites.

An actuator is something that moves something else, so what you are asking about is the type that moves (bends or deforms) when an electrical signal is applied to it. Even the best piezo devices can only move a tiny fraction of an inch. So if you need greater range of motion, you must either attach a lever to the piezo device trading off the amount it can move for greater range of distance) or us a solenoid (which would use much more current) instead.

30 JAN 07, 2105 hrs, GMT.

Answer 2

You need to know that certain crystal materials will produce a voltage when compressed (piezoelectric). This voltage is very linear and stable. If you amplify this voltage it becomes usable in actuating various types of equipment. But, you should remember that the crystal must be deformed by weight, pressure, vacuum or other methods. So these are sometimes referred to as the "actuators".