175B TRACTOR SHOVEL
BENDIX WESTINGHOUSE MODEL 500 AIR COMPRESSOR
moving parts from the engine on which it is
DESCRIPTION AND
mounted.
GENERAL OPERATION
Oil is forced through the oil passage in the crank-
The function of the air compressor is to build up
shaft and out around each connecting rod journal.
a n d maintain the air pressure required to operate
The turning motion of the cranskshaft throws the oil
air power devices and air brake or air auxiliary
that is forced out at the journals, against the cylin-
systems.
d e r bores and crankcase walls, lubricating the
bores and crankshaft bearings.
The Model 500 compressor is a single stage re-
ciprocating piston type compressor with two cylin-
The wrist pins and wrist pin bushings are lubri-
ders. The rate capacity of all Bendix-Westinghouse
cated in two ways depending upon the type con-
compressors is their piston displacement in cubic
necting rods used (Fig. 2). If forged steel rods are
feet per minute when operating at 1,250 rpms. The
used, the oil is forced from the crankshaft through
B e n d i x - W e s t i n g h o u s e Model 500 is rated at 12
a drilled passage in the rod to the wrist pins and
cubic feet per minute (see figure number 1).
bushings. The other type connecting rod which is
currently being used is the aluminum die cast type.
Bendix-Westinghouse
compressors have auto-
The die cast type rod is not drilled between the
matic type inlet valves.
Their unloading mechan-
crankshaft journal and wrist pin connections, but is
i s m s are located in the
cylinder block and they
drilled at the top of the rod. The wrist pins and bush-
have no external moving
parts.
ings are lubricated by oil dripping from a drip-boss
on the piston into a "catch-funnel" at the top of the
The compressor is engine lubricated, which
rod and through the drilled passage to the bushings
means that it obtains the oil necessary to lubricate
and pins.
Figure 2
Pistons and Connecting Rods
Figure 1 Tu-Flo 500
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