Linear DC Motors, Voice
Coil Motors (VCM) or Voice Coil Actuators (VCA) are the simplest type of
electric motors. These motors consist of two separate parts; the
magnetic housing and the coil.
Applying a voltage
across the terminals of the motor causes the motor to move to one
direction. Reversing the polarity of the applied voltage will move the
motor to the opposite direction. The
generated force is proportional to the current that
flows through the motor coil. This force is almost constant in the
specified stroke range of the motor.
Voice coil motors do
not need commutation and using a position sensor, positioning accuracies
of less than one micron or 0.00004 inches are achievable.
The non-commutated
motor construction increases reliability. The direct coupling of the
motor to the load allows for fast acceleration / deceleration and high
speed operation.
Speeds as high as 80
inches per second (2 meters per second) and accelerations as high as 20g
(20 m/sec2) are easily achievable.
The moving part needs
to be supported by a mechanism supplied by the customer.
This type of motor may be used in conjunction with a
position sensor and a motion controller for accurate positioning.
All the following motors are also available with
metric thread.