PNEUMATIC PRESSURE INDICATOR MECHANISM

When a pressure is developed, air enters through hole 1 and raises piston 2 in a transparent cylinder of plexiglas. At the end of the piston stroke, rubber insert 4 closes the hole in cover 5 leading to the atmosphere. The side surfaces of the piston are painted red. By watching the piston, the operator can tell when he has air under pressure. When hole 1 is connected to the atmosphere, piston 2 d…