Structural knowledge of electromagnetic buzzer

02/08/2021
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Electromagnetic buzzer is often used in buzzer. The main structural components include iron core, coil, magnetic ring, PCB component, shell, diaphragm, etc. the following is followed by the small series of SMD buzzer to see what its structure is!
1. Iron core: it is mainly divided into two processing technologies: stamping and die casting. The material is an iron nickel coating. The reason for choosing iron is better permeability, and nickel coating is added to achieve the purpose of rust prevention. The core buzzer is mainly used as the support for PCB, permeability and gap control action, so the height and dimensional accuracy of the core are high, and the overall tolerance is controlled within ± 0.01 mm.

2. Coil: self-adhesive enamelled copper wire is used. The number of turns of the working coil is controlled by the microcomputer winding machine system, and the self-adhesive fixed value is reached through the alcohol concentration.

3. Magnetic ring: ferrite beads, constant magnetic field. In the buzzer, the main vibration superimposes the electromagnetic field on the diaphragm.

4. Diaphragm: it is made of iron nickel alloy and consists of two connectors of different sizes. It is composed of controlled high current spot welding. It is mainly used as vibration source in buzzer. Generally, the working frequency can be adjusted through a smaller diaphragm. The thicker the smaller diaphragm, the lower the frequency, and the thinner the frequency, the higher the frequency.

5. PCB assembly: epoxy copper single panel, in which the main function of the passive buzzer is connected and fixed to the fixed and enamelled wire lead or pin, the excessive active buzzer oscillation part.

6. Shell: ABS, PPO, LCP, PBT and other materials are generally used for injection molding. Different temperature resistant materials can be selected according to the customer's welding methods. The main function of the buzzer is to protect and amplify all components.
The above is the introduction of the structure knowledge of SMD buzzer. I hope it can help you.