What is Moving Coil?
At the heart of all SMAC actuators is the moving coil, also described as a voice coil actuator. The essential principle is the same as you will find in any permanent magnet loudspeaker. The voice coil sits in a strong magnetic field, and by passing a current through the coil a force is generated in either direction. With SMAC actuators, the moving coil makes an ideal linear motor.
The amount of force generated is governed by the equation:
F N I B
F is the force generated
N is the number of turns in the winding (Constant)
I is the current flowing through the winding and
B is the magnetic flux (Constant)
Therefore, by controlling current we can accurately control the force output.
Benefits of Moving Coil Technology
- Lower moving mass with the voice coil actuator means extremely high acceleration and velocity, as opposed to the heavier “moving magnet” technology used in most linear motors.
- Safe and energy efficient: operates at low current, typically at 1.5 amps at 24 volt DC.
- Quite (< 55dB), airless operation: no expensive compressed air generation required. No air consumption or air leaks to attend to. No compressed air generating environmental particulate contamination.
- No pressure valves, no force fluctuations caused by air pressure fluctuations.
SMAC Unique Features and Advantages
- Fully programmable in Position, Acceleration, Velocity and Force.
- Direct drive = no backlash, a very high degree of accuracy & repeatability.
- Sub-micron resolution (5µm to 100nm)
- Force control = Soft-Land capability: light force without damaging parts/material being handled.
- >250 million cycles MTBF = long operation life
SMAC Actuators Offer Flexibility:
- Integrated position measuring system with glass scale and optical reader head (no contact wear).
- Ability to switch between operations - force, position and velocity mode - at any time.
- “On the fly” adjustable movement allows quick changeover.
- Constant force monitoring and control.
- Digital and analog input/output channels.
- SMAC linear motors are a servo system, hence can be programmed to decelerate smoothly and quickly. Mechanical slamming can be totally eliminated.
- Competitively priced electric actuators that offer all above features and benefits.
Take a look at this side-by-side comparison of moving coil technology vs pneumatics.
For more information on SMAC actuators, contact us to request a product demo.