THEORY OF OPERATION (SHEET 2 OF 2)
Unloader Operation. When pressure in air reservoir is at high pressure setting of
governor, governor sends pressurized air to unloader.
This pressurized air pushes
diaphragms and plungers down to hold inlet valve open.
With inlet valves held open,
there is no compression of air and air moves between two cylinders. When pressure in
air reservoir is at low pressure setting of governor, governor stops flow of pres-
surized air to unloader.
The pressurized air in unloader leaves through an exhaust
port in governor and compression cycle begins again.