One article to share the use of electromagnetic buzzer
Electromagnetic buzzer is a kind of buzzer, which is different from piezoelectric buzzer. Electromagnetic buzzer is an electronic buzzer that uses electromagnetic coil to sound the buzzer and is used to make sound devices for electronic products. Electromagnetic buzzers are widely used in computers, printers, copiers, alarms, electronic toys, automotive electronic equipment, telephones, timers and other electronic products for sounding devices; piezoelectric buzzers for music greeting cards, electronic doorbells and electronic toys and other small electronic products for sounding devices.
According to the different construction methods, can be divided into: electromagnetic buzzer and piezoelectric buzzer.
1, electromagnetic buzzer
electromagnetic buzzer mainly uses the characteristic that the energized conductor will generate magnetic field, and uses a fixed permanent magnet and the energized conductor to generate magnetic force to push the eardrum fixed on the coil. Electromagnetic due to good timbre, so more for voice, music and other equipment.
2, Piezoelectric Buzzer
The main component of the piezoelectric buzzer is an electronic sound element called a piezoelectric ceramic sheet, which is a piezoelectric ceramic dielectric material placed between two copper circular electrodes. When an AC audio signal is connected to the two electrodes, the piezoelectric sheet vibrates according to the magnitude and frequency of the signal to generate corresponding sound. The difference between
electromagnetic buzzer and piezoelectric buzzer
piezoelectric buzzer uses the piezoelectric effect of piezoelectric ceramics to drive the vibration of metal sheets to produce sound. The electromagnetic buzzer uses the principle of electromagnetism to suck down the metal diaphragm when energized and bounce back according to the elastic force of the diaphragm when not energized, so the piezoelectric buzzer is driven by square wave.
electromagnetic type is 1/2 square wave drive, piezoelectric buzzer requires a relatively high voltage to have sufficient sound pressure, generally recommended for more than 9V. Some specifications of piezoelectric can reach the above, and larger sizes are also easy to reach. The electromagnetic buzzer can emit more than 1.5V sound pressure.
Then we all know that piezoelectric buzzers mainly rely on pulse current to act on piezoelectric ceramics, thereby causing piezoelectric ceramics to vibrate and sound. However, in this case, the sound is relatively small, so we need to often install an auxiliary sound cavity on one side to improve the sound. Then some piezoelectric buzzers are equipped with light-emitting diodes, which are mainly different from the coil of the energized part moving in the magnetic field composed of permanent magnets, the sound disc glued to the coil is driven to vibrate and sound, and the sound quality is better than that of the piezoelectric type.
When the electromagnetic buzzer is turned on, the audio signal current generated by the oscillator will pass through the electromagnetic coil, causing the electromagnetic coil to generate a magnetic field, then the vibrating diaphragm will interact with the electromagnetic coil and the magnet Under the action, vibration occurs periodically.
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