Komatsu 730E - Injector Operation

OM4211 07/09 Maintenance - Section 42
Automatic Lubrication System Page 42-11
INJECTOR OPERATION
STAGE 1.
Injector piston (2)
is in its normal or
rest position. Dis-
charge chamber
(3) is filled with lu-
bricant from the
previous cycle.
Under the pres-
sure of incoming
lubricant (6), slide
valve (5) is about
to open passage
(4) leading to mea-
suring chamber
(1) above injector
piston (2).
STAGE 2.
When slide valve
(5) uncovers pas-
sage (4), lubricant
(6) is admitted to
measuring cham-
ber (1) above in-
jector piston (2),
which forces the
lubricant from dis-
charge chamber
(3) through outlet
port (7) to the
bearing.
STAGE 3.
As injector piston (2)
completes its stroke,
it pushes slide valve
(5) past passage (4),
cutting off further ad-
mission of lubricant
(6) to passage (4)
and measuring
chamber (1). Injector
piston (2) and slide
valve (5) remain in
this position until the
lubricant pressure in
supply line (6) is
vented.
STAGE 4.
After venting, the in-
jector spring ex-
pands, causing slide
valve (5) to move, so
that passage (4) and
discharge chamber
(3) are connected by
valve port (8). Fur-
ther expansion of the
spring causes the
piston to move up-
ward, forcing the lu-
bricant in measuring
chamber (1) through
passage (4) and
valve port (8) to refill
discharge chamber
(3).
The injector is now
ready for the next
cycle.