A simple buzzer is an electro-acoustic transducer that converts electrical energy into sound energy. It is commonly used to produce a buzzing or beeping sound in various electronic devices like alarm clocks, doorbells, and electronic toys. The basic construction of a simple buzzer consists of a coil of wire, a magnet, and a diaphragm.
Here's how it works in an electrical circuit:
Coil of Wire: The buzzer contains a coil of wire, usually made of copper, wound around a hollow or solid core. This coil acts as an electromagnet when an electric current flows through it.
Magnet: Inside the coil, there is a permanent magnet or a ferromagnetic material. This magnet provides a magnetic field within the coil.
Diaphragm: Connected to the coil is a flexible diaphragm, usually made of thin metal or plastic. The diaphragm serves as the vibrating element.
Circuit Connection: The buzzer has two terminals, typically labeled as positive (+) and negative (-). When you connect the buzzer to a power source, current flows through the coil and creates a magnetic field around it.
Electromagnetic Attraction: When the current flows through the coil, it turns the coil into an electromagnet. The magnetic field produced by the coil interacts with the permanent magnet or ferromagnetic material inside the coil, causing an attraction or repulsion force between them.
Diaphragm Movement: As the magnetic force attracts or repels the diaphragm, it causes the diaphragm to move back and forth rapidly.
Sound Generation: The rapid movement of the diaphragm creates compression and rarefaction waves in the surrounding air, generating sound waves. The frequency of the sound depends on the rate of the diaphragm's movement, which, in turn, depends on the frequency of the electric current flowing through the coil.
Continued Operation: As long as the electric current is supplied to the buzzer, it will continue to produce sound. When the current is removed, the magnetic field dissipates, and the diaphragm returns to its resting position, stopping the sound.
By controlling the electric current's on/off pattern through an electronic circuit, you can create different buzzing or beeping patterns to suit the intended application of the buzzer.