1-22. ELECTRO-OPTICAL TEST BENCH SET
The electro-optical test bench set is comprised of a dayside test bench, test
console test bench, and a nightside test bench, mounted to a common base assembly.
The base assembly together with the pneumatic system (FO-11) provides Support,
leveling, and isolation of the electro-optical test bench set. The dayside test
bench, test console test bench, and nightside test bench are described in paragraphs
1-23, 1-24, and 1-25.
b. PNEUMATIC LEVELING AND ISOLATION SYSTEM
(1) Pneumatic Isolators.
The E/O bench assembly is supported by four air springs
(isolators) controlled by three height sensing servo valves. When the isolators are
deflated, the E/O bench assembly rests on four pivot plates. (The pivot plates fit
into pivot plate sockets on the base assembly. ) The three master isolators (isolators
with servo valves) control the height of the base assembly. Once the system is
activated and operating height adjusting screws are locked, the base assembly
maintains its height and remains level, even though the total weight and/or center of
This function is performed by the height sensing mechanical servo
When the load on each master isolator is balanced by the internal air
pressure, both sides of the servo valves remain closed. When the load is decreased,
the bleed side of the valve opens and releases pressure. The preset position of the
base assembly with respect to the floor remains fixed.
(2) Pneumatic Control Panel.
Air pressure (maximum 125 psi) from a facility air
supply is supplied to an on/off valve on the pneumatic control panel. When the valve
is opened (on or down position) air is routed through an air filter to an air
The air regulator is used to reduce air supply pressure to an operating
From the air regulator, air is routed through the REGULATED AIR PRESSURE
gage to three servo valves.
The three servo valves are attached to isolators number
1, number 2, and number 3.
Isolator number 4 (located at rear of dayside test bench)
is controlled by the servo valve attached to isolator number 3.
Air pressure from
each servo valve output is monitored by a gage on the front of the panel.