VOICE COIL MOTORS
Voice Coil Actuators are the technical implementation of the Lorentz-Force-Principle: The force of a current carrying conductor in a magnetic field is proportional to the field strength and the current. An alternation in the current direction also alternates the direction of the force so that voice coil actuators are bidirectional actuators with similar behaviour in both directions. Both rotary and linear versions are available. Electrically voice coil motors are single phase motors and can be operated like conventional DC-motors. One big advantage e.g. over proportional solenoids is the extremely small hysteresis which makes voice coil actuators ideally suited for applications requiring well controllable movement in both directions. Also requirements regarding audible noise, small overshoot or very good controllability on force can be fulfilled easily with voice coils.
General characteristics of voice coil motors:
- very small hysteresis
- no cogging
- high dynamic response due to small moving mass
- high overload capacity
Voice coil motors very often are supplied as pure actuators, where the feedback for the control is derived from other variables in the application, e.g. like pressure or gas mixture in medical or valve applications.
Some customers would like to do all the integration of components for their applications. For this purpose we supply two families of voice coil actuators, with no integrated sensors and only limited or no guiding: The VM series (standard with linear sleeve bearing; custom version without bearing possible) and the CVC series with no bearing.
Our partner SMAC went the opposite direction and supplies fully integrated voice coil actuators with a long life bearing and encoder as position feedback, so that together with an according servocontroller these voice coil actuators can directly be used as system components in a positioning system. Further versions also include a rotary movement in addition to the linear actuation and gripper type versions. On customer demand also multi axis systems are available.
As servocontroller for voice coil motors we recommend:
Our Voice Coil Motor models:
- VM: voice coil actuators in pot version with integrated sleeve bearing as standard; 1 to 45N continuous, 16 to 80mm diameter, stroke up to about 30mm, custom versions welcome!
- CVC: voice coil actuators in pot version without guiding, up to 612,5N continuous, 20 to 180mm diameter
- CAL: round voice coil actuators with 12 / 35 / 36 / 75mm diameter with up to 25N continuous force; integrated with long life bearing and encoder with up to 0.1µm resolution; stroke up to 50mm, made to replace pneumatic cylinders and LVDTs!
- LAL: linear voice coil actuator in block design with up to 500N force, integrated with long life bearing and encoder with up to 0.5µm resolution; stroke up to 100mm
- LAR: rotary / linear voice coil actuator in block design with up to 100N force / 0.13Nm torque, integrated with long life bearing and encoder up to 0.5µm / 20,000 counts / rev resolution; stroke up to 100mm
- LXY(Z): up to 3 axis, up to 100N force, integrated with long life bearing and encoder with up to 0.5µm resolution; stroke up to 100mm
- GRP: gripper mechanism, up to 45N force, integrated with long life bearing and encoder with up to 0.5µm resolution; stroke up to 15mm