About electromagnetic actuators............
General
1. Simple electromagnetic actuator is a specially design electromagnet that consists of a coil and a movable iron core
When the coil is energized, the core moves
The movable core is usally spring-loaded to allow the core to retract when coil is not energized.
The force generated is approximately proportional to the square of the current
and inversely proportional to the square of the length of the air gap.
Basically it converts electric energy to linear motion.
2. Magnetic actuators and sensors use magnetic fields to produce and sense motion.
Magnetic actuators allow an electrical signal to move small or large objects. To obtain
an electrical signal that senses the motion, magnetic sensors are often used.
3. Even electric motor with driver and position control are electromagnetic actuator with electronic control.
( spindle motors, linear motors, positioning systems with motor )
For ex. They are used in
relays and contactors
hydraulic and pneumatic valves
speaker/voice coils
electric door locks
automotive start motors
Electrohydraulic valves in airplanes, tractors, robots, automobiles, and other
mobile or stationary equipment
Fuel injectors in engines of automobiles, trucks, and locomotives
Biomedical prosthesis devices for artificial hearts, limbs, ears, and other organs
Head positioners for computer disk drives
etc...
Vacuum circuit breaker with magnetic actuator mechanism
**broken link removed**
http://www05.abb.com/global/scot/scot235.nsf/veritydisplay20guide.pdf
Electronic Control & Monitoring of PM Actuators
IPEC Engineering Ltd - Electronic Control & Monitoring of PM Actuators
Magnetic Actuators and Sensors, by John R. Brauer
http://media.wiley.com/product_data/excerpt/92/04717316/0471731692.pdf
Magnetic actuators
CEDRAT Group: Magnetic actuators
KAK