TRUCK SERVICE MANUAL
BREAK-AIR
Fig .
2 Sectional View of Compressor Oiling System
Fig .
1 Exterior View of TuFlo 400 and 5 Compressor
OPERATION
DESCRIPTION
The compressors run continuously while the
engine is running, but the actual compression of air is
The TuFlo
500
compressors are single
controlled by the governor, which, acting in conjunction
acting reciprocating piston type compressors. The rated
with the unloading mechanism in the compressor
capacity of a compressor is based on the piston
cylinder block, starts or stops the compression of air by
displacement in cubic feet per minute when operating at
loading or unloading the compressor when the pressure
1250 RPM.
in the air brake system reaches the 'desired minimum
(8085 p. s. i. ) or maximum (100105 p.s. i. ).
The capacity of the TuFlo
500 is 12 cubic feet per minute.
Compressing Air (Loaded)
The TuFlo 500 and 600 compressors
During the down stroke of each piston a partial
have water-cooled cylinder heads and water-cooled
vacuum is created above the piston which unseals the
cylinder blocks. Various mounting and drive adaptations
inlet valve, allowing air drawn through the intake strainer
are used depending on design of the engine.
to enter the cylinder above the piston, Fig. 3. As the
piston starts the upward stroke, the air pressure on top of
Engine lubricated compressors are dependent
the inlet valves plus the inlet valve return spring force
on the vehicle engine for oil and oil pressure, Fig. Z. In
closes the inlet valve. The air above the piston is further
these compressors oil from the vehicle engine enters the
compressed until the pressure lifts the discharge valve
compressor through a passage in the compressor end
and the compressed air is discharged through the
cover and is fed to the connecting rod bearings through
discharge line into the reservoir, Fig. 4. As each piston
drilled holes in the crankshaft. The wrist pins are
starts its down stroke the discharge valve above it
lubricated through holes in the top of the connecting rod
returns to its seat, preventing the compressed air from
wrist pin bearing and bushing by means of oil dripping
returning to the cylinder, and the same cycle is repeated.
from a drip boss on the piston. The main bearings are
splash lubricated. Surplus oil returns to the engine
crankcase through the open compressor base.
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