Electromagnetic Device Surpasses Hydraulic Piston for Controlling Motion

Advanced Motion Technologies

Electromagnetic actuators take the place of hydraulic cylinders

Since the late 1700´s, the venerable hydraulic piston has been the mainstay for controlling mechanical motion. However, hydraulics have numerous drawbacks: they are relatively clumsy, leak pollutants, require frequent maintenance, and are energy inefficient and susceptible to corrosion.

This article features a new technology that is electromagnetic instead of hydraulic -- a completely new type of electric linear motor that is more precise, energy-efficient, extremely powerful, and easier to maintain than is the hydraulic piston. Called an electromagnetic actuator, this device features a single moving part that is capable of thrusts between 2.2 pounds (1kg) and 100 tons. The patented technology uses a magnet array mounted on a piston/armature that moves on simple slide bearing rings inside a coil array cylinder. The armature is sealed, creating a pneumatic piston with an internal gas spring reservoir that can be tuned for maximum efficiency and used to counteract motion caused by the deadweight of any device to which it is attached. Unlike a piston, the electromagnetic actuator features an output shaft through one end of the cylinder, enabling the device to be mounted by the other end to a universal joint for maximum movement in virtually any direction. And because everything is internal, the entire device can be fully sealed and watertight, capable of operating in both sterile and harsh environments. Unlike hydraulic pistons, this actuator is totally silent and extremely smooth, making it ideal for closed areas and an almost unlimited number of applications.

The remarkable precision, strength, and flexibility of this technology make it perfect for a wide range of uses, including entertainment rides/games; training simulators, precision manufacturing (robotics, pick-and-place operations), automotive (suspension, steering, stabilization), marine steering and jet aircraft launching; flying shears in industry; elevator closures; weight-bearing motion (entry opening and shock absorbing systems); and periscopes, to name a few.