TM 5-4310-376-14
1-13. COMPONENT DESCRIPTIONS - Continued
Exhaust Stroke
The exhaust valve opens and the upward stroke of the piston forces
out all of the burnt gases.
The exhaust valve closes, the intake valve opens, and the engine is
ready to repeat the cycle just described.
EXHAUST STROKE
COMPRESSOR PUMP
1.
LOW PRESSURE PISTON 5.
EXHAUST VALVE
2.
INLET VALVE
6.
INTERSTAGE RELIEF VALVE
3.
AIR INLET
HIGH PRESSURE PISTON
7.
4.
EXHAUST VALVE
INTERCOOLER
8.
The cycle starts with the low pressure piston (1) at the top of its stroke. When the piston
moves down (suction stroke), the inlet valve (2) opens and air is drawn through the air inlet
(3) into the cylinder.
On the upstroke (compression stroke), the inlet valve (2) closes and the piston pushes air out
into the intercooler tube (4) through the exhaust valve (5).
The interstage relief valve (6) is a safety valve to protect the first-stage against damage from
over pressure. It is set to release at approximately 60 psi.
The compression stroke of the high pressure piston (7) (second stage) compresses the air to the
final discharge pressure and forces it through the exhaust valve (8) into the unloading control
valve.
If there is an excessive pressure buildup due to a stuck valve or other air blockage, the air tank
safety valve opens to prevent damage to the compressor.
UNLOADING CONTROL VALVE
When the compressor starts, air is delivered through air inlet tube through check valve (1), and
exits from air outlet (2) to the air tank.
1-6
