*3.7.1 Piezoelectric printers*

There are two main types of printers that use piezoelectric actuators:

## *3.7.1.1 A dot-matrix printer*

In a piezoelectric dot matrix printer (**Figure 8**), piezoelectric actuators in the printer head move needle-like pins that "poke" through a strip of ink tape (similar to a typewriter) against a piece of paper in various patterns to form characters. For most applications, the use of dot-matrix printers has been superseded by other technologies. However, a dot-matrix printer is the only printer technology capable of generating duplicate and triplicate carbon-copy printouts.

#### *3.7.1.2 Inkjet printer*

In a piezoelectric inkjet printer, piezoelectric actuators in the printer head act on small diaphragms or otherwise change the geometry of an inkwell so that ink droplets are forced out of an orifice onto paper. This is one of the dominant technologies in the printer market to date (**Figure 9**).

#### *3.7.2 Piezoelectric speakers*

Piezoelectric speakers are featured in virtually every application that needs to efficiently produce sound from a small electronic gadget. These types of speakers

*3.7.3 Piezoelectric buzzers*

*Piezoelectricity and Its Applications*

*DOI: http://dx.doi.org/10.5772/intechopen.96154*

*3.7.4 Piezoelectric humidifiers*

*3.7.5 Electronic toothbrushes*

*3.8.1 Piezoelectric igniters*

and improvised potato cannons.

that can either be used or stored for later use.

*(a) Piezoelectric buzzer block diagram. (b) Piezoelectric buzzer.*

*3.8.2 Electricity generators*

**Figure 11.**

**85**

electronic toothbrushes (**Figure 11**).

Piezoelectric buzzers are similar to piezoelectric speakers, but they are usually designed with lower fidelity to produce a louder volume over a narrower frequency

Many cool mist humidifiers use a piezoelectric transducer to transmit ultrasonic

Linear piezoelectric actuators are implemented to vibrate the bristles in some

This is, perhaps, the most well-known and ubiquitous use of piezoelectricity. In piezoelectric igniters, a button or trigger is used to cock and release a spring-loaded hammer, and the hammer is used to strike a rod shaped piezoelectric ceramic. The sudden mechanical shock to the piezoelectric ceramic produces a rapid rise in voltage that is high enough to jump a sizable spark gap and ignite fuel. Piezoelectric igniters are commonly used for butane lighters, gas grills, gas stoves, blowtorches,

Some applications require the harvesting of energy from pressure changes, vibrations, or mechanical impulses. The harvesting of energy is possible by using piezoelectric materials to convert deflections or displacements into electrical energy

range. Buzzers are used in a seemingly endless array of electronic devices.

sound energy into a pool of water. The ultrasonic vibrations cause fine water droplets to break away and atomize from the surface of the pool where they become

entrained in an air stream and enter the desired space.

**3.8 Piezoelectricity other applications in daily life**

**Figure 8.** *A dot-matrix printer.*

**Figure 9.** *Inkjet printer working.*

**Figure 10.** *Piezoelectric speakers.*

are usually inexpensive and require little power to produce relatively large sound volumes. Thus, piezoelectric speakers (**Figure 10**) are often found in devices such as the following:


## *Piezoelectricity and Its Applications DOI: http://dx.doi.org/10.5772/intechopen.96154*
