ABSTRACT
Direct linear electrical propulsion systems have been in use for some time, a well known example being the maglev passenger transport system at Birmingham International Airport. The system as a whole is managed by a supervisory system which handles automatic train operation vehicle propulsion functions and automatic train protection safety functions. Motor and lead screw is similar in many respects to the motor and ball screw. The principal difference is the higher friction generated at the nut/screw interface. The working pressures for hydraulic systems are typically between 100 bar and 300 bar, and may be higher in military equipment where economy of space is a major consideration. Thus construction is almost always in steel. Actual or potential applications for such devices include central door locking systems for cars and the remote operation of on/off fluid control valves.
