HYDRAULIC SYSTEM
TM 5-3805-258-24-1
SYSTEMS OPERATION
S C H E M A T I C O F S T E E R I N G A ND
I M P L E M E N T
S E C T I O NS
1 . C a m r i n g . 2 . R o t o r . 3 . O u t l e t . 4 . V a n e . 5 . I n l e t . 6 .
Slot. 7. Passage. 8. Inlet. 9. Insert. 10. Outlet, A, B, C, D, E
and F. Positions of vanes.
As rotor (2) turns, the vanes in positions (E) and
(F) move out and follow the shape (contour) of the
cam ring. The chamber area between the vanes in-
creases which causes a low pressure or vacuum in the
chamber. This pressure difference causes oil to flow
through inlet (8). The oil fills the space between
vanes at positions (D) and (E) and continues to fill
the space through positions (A) and (D). Oil between
the vanes at positions (A) and (D) will be trapped
(held) when the vane at position (D) passes the end of
inlet (8). As rotor (2) continues to turn, the vanes are
pushed in by the contour of cam ring (1). The
chamber area between the vanes now decreases. Oil
between the vanes at positions (A) and (B) is pushed
into outlet (3). The oil continues to be pushed out
through positions (B) and (C). When the vane at
position (B) passes the end of outlet (3), the cycle is
completed.
Both ends of the vanes are connected by passages
(7) in the rotor. The oil found in these passages keeps
the pressure even on both ends of the vanes and
permits the oil behind the vanes to go out (escape) as
the vanes are pushed back in.
Operation Of The Pilot Pump Section
The components of the pilot section are: a plate,
adapter, seal packs, cam ring (2), rotor (1) and vanes
(8). The operation of the pilot section is the same as
the other two sections, except that the pilot section
does not have inserts inside the vanes.
S C H E M A T I C O F P I L O T P U M P S E C T t ON
1. Rotor. 2. Cam ring. 3. Outlet. 4. Passage. 5. Inlet. 6.
Inlet. 7. Outlet. 8. Vane. A, B, C, D, E, F and G. Positions of
v a n e s .
At first, vanes (8) are pushed out against cam ring
(2) by centrifugal force. Pressure oil in passages (4)
of rotor (1) keeps the vanes pushed out against the
cam ring. Both ends of the vanes are connected by
these passages. This oil keeps the pressure even on
both ends of the vanes and permits the oil behind the
vanes to go out (escape) as the vanes are pushed back
in.
As rotor (1) turns, the vanes in positions (F) and
(G) move out and follow the shape (contour) of the
cam ring. The chamber area between the vanes in-
creases which causes a low pressure or vacuum in the
chamber. This pressure difference causes oil to flow
through inlet (6), The oil fills the space between
vanes at positions (F) and (G) and continues to fill
the space through positions (E) and (A). Oil between
the vanes at positions (E) and (A) will be trapped
(held) when the vane at position (E) passes the end of
inlet (6). As rotor (1) continues to turn, the vanes are
pushed in by the contour of cam ring (2). The
chamber area between the vanes now decreases. Oil
between the vanes at positions (A) and (B) is pushed
into outlet (3). The oil continues to be pushed out
through positions (C) and (D). When the vane at
position (C) passes the end of outlet (3), the cycle is
completed.
Operation Of The Pilot Section Relief Valve
NOTE
Models 950BNSCE and 950BSCE have a screen in the
chamber for spring (6).
Pressure oil from the pilot pump section comes into
housing (11) through inlet (1). At this time, valve (2)
is closed and the oil goes through orifice (8) and
outlet (9) to the steering and implement pilot sys-
tems. Some of this oil also goes through orifice (10)
to the chamber for spring (6).
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