Scanning For Ideas: Shaped Pistons Let Air Cylinder Move Smoothly
Most air cylinders are prone to wear and contamination, don’t withstand extreme temperatures, and generate significant friction.
Edited by Stephen J. Mraz
The Airpel-AB single-acting (air-extend)
pneumatic drivers from Airpot Corp., Norwalk,
Conn. (airpot.com), overcome these limitations with a
specially shaped steel piston fitted to a borosilicate glass
cylinder. Putting pressurized air into the cylinder creates
an air-bearing airflow effect around the piston. So the
same air that drives the cylinder generates a stiff cushion
of air that supports the piston around its edge, preventing
contact with the cylinder wall and reducing friction
without lubricants. A low-friction ball joint connects the
rod to actuator, so no output force is lost to friction.
The AB line is offered in four bore diameters and 10
strokes, and can provide driving or supporting forces
ranging from 2 gm to 58 kg at pressures starting at 5 psi.
They operate in temperatures from –20 to 90°C. Because
there is little friction or wear, the manufacturer guarantees
their AB air cylinder will outlast any piece of equipment
in which it is installed.