Piezo technology
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The piezo technology is concerned with applications that use the so-called piezoelectric effect utilize certain crystals or polymers.
If an electrical voltage is applied to a piezoelectric crystal, it reacts with a mechanical tension, which leads to a change in shape. On the other hand, if a mechanical tension is exerted, the piezocrystal reacts conversely by generating an electrical tension.
In the piezo printer , this form changeability is used in tiny piezo nozzles to eject the ink in small droplets. Here are frequencies up to 23 kHz reached. Piezo printers are used in many ways in the field of marking, e.g. B. Barcode printing on packaging and in high-performance printing systems for advertising and textiles.
Further areas of application of the technology are the crystal scanners of turntables . The stylus is attached to two crystals arranged at 90 ° to each other, which read the side writing of the groove.
The piezoelectric crystals allow very high frequencies. They are also used as very sharply delimiting surface acoustic wave filters in radio reception technology.
In addition, they are used to generate ultrasound in cleaning systems in the kilowatt range.
There are also successful attempts to use piezo technology to generate electricity from human energy . Piezo elements are installed in boot heels or in the flooring of heavily frequented paths and squares.
This effect is also used in part for vehicle detection on traffic light systems with traffic-dependent controls.