How voice coil motor works in speaker?
Loudspeakers were used to amplify or create a louder voice, thus
the name “voice coil” stuck. Voice coil motors use similar
technology to speakers, but they are designed to produce higher
forces over larger distances or “strokes”. Voice coil motors do not
have the commutator but uses a position sensor. These motors
consist of two separate parts; the magnetic housing and the coil.
voice coils typically consist of:
1.non-magnetic center pole;
2.cylindrical coil connected to the power supply;
and an outer cylindrical permanent magnet.
3.The current running through the coil creates a magnetic field,
which interacts with the field established by the permanent magnet.
The voice coil works because of the force between a static magnetic
field and an electric current perpendicular to the field.
Voice Coil Motor Characteristics:
1. Reliability – side forces developed are negligible, so bearing
loading can be very low to enable long life operation;
2. Simplicity – the voice coil motor is a single pole device
requiring no commutation. Both the device itself, and the
associated controller can be very simple and robust;
3. Flexible Configuration – the principle of operation lends itself
to many different mechanical layouts allowing great flexibility in
the design of associated systems;
4. Fast operation – Low electrical inductance, and low moving mass
enable fast inflow of current and high acceleration. Acceleration
of >500G is possible with custom devices;
