MTS Series 248 Actuators - Manual (Page 17)

About Actuator Operation
Series 248 Actuator Product Information Introduction 17
Functional Description
About Actuator Operation
Actuator piston rod movement is accomplished by supplying high- pressure
hydraulic fluid to one side of the actuator piston and opening the other side to a
return line. High-pressure hydraulic fluid is ported into the cylinder through the
retraction port or the extension port. The differential pressure across the piston
forces the piston rod to move. The amount of hydraulic fluid and the speed and
direction of piston rod movement is controlled by a servovalve.
If the piston rod contacts some external reaction point, then a force is applied to
that point equal to the effective piston area times the actuating pressure. The
main criteria for selecting an actuator are the force and stroke (displacement)
required for the job.
Retraction
Port
Extension
Port
LVDT Core
Mount
LVDT Core
Extension
LVDT Coil