A system consisting of several devices which continuously monitor
actual information (position, velocity), compares those values to
desired outcome and makes necessary corrections to minimize that
In motion control, the portion of a move made at a constant
The order of a series of operation or movements, To drive flow
of accomplish a subsequent operation or movement.
Valve: A pressure operated valve which, at its setting, diverts
flow to a secondary line while holding a predetermined minimum pressure
in the primary line.
Data Transmission: A form of digital data transmission in which
the data bit of a binary word are processed or transmitted one at
a time. Slower than parallel data transmission, but does not require
separate circuitry for each bit.
Mechanism: A mechanism subjected to the action of a controlling
device which operates as if it were directly actuated by the controlling
device, but capable of supplying power output many times that of
the controlling device, this power being derived from an external
and independent source.
Valve: A valve which modulates output as a function of an input
command, A flow valve.
Acting Cylinder: A cylinder in which hydraulic energy can produce
output as a function of an input command., A follow valve.
Internal leakage of hydraulic fluid.
An electromechanical device that converts electrical energy
into linear mechanical motion. Used to actuate directional valves.
May be air gap or wet armature type.
A coarse filter.
Torque: The maximum torque available at zero speed.
Angle: The angle the shaft rotates upon receipt of a single
The ability to resist movement induced by an applied torque. Is
often specified as a torque displacement curve, indicating the amount
a motor shaft will rotate upon application of a known external force
The length of travel of a piston or plunger, To change the displacement
of a variable displacement pump or motor.
An auxiliary mounting for a hydraulic component providing a
means of connecting piping to the component.
Line: The hydraulic line connecting the pump inlet port to the
reservoir or sump.
A rotary electromagnetic device generally used as an AC feedback
signal generator which indicates position. It can also be used as
a reference signal generator.
A Motor rotating at a speed correctly corresponding to the applied
step pulse frequency is said to be in synchronism. Load torques
in excess of the motor's capacity (rated torque) will cause a loss
of synchronism. The condition is not damaging to a step motor.