Electromagnetic buzzer: What are the working principles of electromagnetic buzzer?
Electromagnetic buzzer AC signal generates alternating magnetic flux on the rod of the bracket through the wire wound on the bracket. The alternating magnetic flux is superimposed with the constant magnetic flux of the magnetic ring, so that the molybdenum sheet vibrates at a given AC signal frequency. And cooperate with the resonant cavity to sound.
What are the working principles of the electromagnetic buzzer recommended by Fuhongda?
The response curve of the overall frequency and sound pressure of the speaker product is directly related to the gap value, the natural vibration frequency of the molybdenum plate (which can be roughly refracted to the thickness of the small molybdenum plate), the frequency of the shell (Helmholtz resonator), and the magnetic intensity of the magnetic ring.
buzzer chip, coupled with a specific oscillation circuit and resonant cavity, has become a finished buzzer. What you remove from the induction cooker is only a honeycomb, there is no oscillation circuit, and the resonant cavity is on the shell of the induction cooker! To make a buzzer, there must be a resonant cavity and an oscillation circuit.
It is also necessary to know the resonant cavity. If there is no resonant cavity, the sound will be very small! In addition, each beehive has its own specific oscillation frequency, and only at this frequency can it make a stronger sound.
If only you had the means to test. You can measure the operating frequency of the buzzer in your hand. Then make an oscillation circuit of this frequency, and then make a resonant cavity. Here is the oscillation circuit. The oscillation frequency should be adjusted according to the frequency of your buzzer.
Generally, a low-power buzzer can be used. If you want to make a beep, you need to add a modulation circuit to the oscillation circuit to make a sound similar to an alarm clock. Just like the previous circuit, the oscillation frequency is much smaller to more than 100 times smaller.
Piezoelectric buzzer uses piezoelectric material, that is, when the piezoelectric material is deformed by external force, the piezoelectric material will generate electric charge. Similarly, piezoelectric materials deform when energized.
The electromagnetic buzzer mainly uses the characteristics that the energized conductor can generate a magnetic field, and uses a fixed magnet and an energized conductor to generate magnetic force to push the eardrum fixed on the coil.
Due to the different sounding principles of the two buzzers, the piezoelectric structure is simple and durable, but the single tone and tone are poor, and it is suitable for equipment such as alarms. Electromagnetic because the sound is good, so for voice, music and other equipment.
above is the content collected by Changzhou fuhongda electronics co., ltd. if necessary, please contact us.
Mobile two-dimensional code