Yale A7S1, Руководство по обслуживанию

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On the drive shaft side, a fluid seal is installed on the
pump housing. A seal between the pump housing and
the cover rely on a specially-shaped seal ring.
STEERING CONTROL UNIT
The steering control unit is a gear pump consisting of a
pump housing, pump cover, one pair of gears, a
bearing, and seal rings. The pump employs a load-
balancing bearing and a special lubrication method
which minimizes the gap at the gear ends.
Because the pump housing and pump cover are made
from aluminum, they are light and sturdy. The active
gear and the passive gear each have two shafts that
are individually installed on the pump housing
bearings. These bearings are made of special
material, to bear the radial load of the gear and also
serve as the baffle seats for the gear ends.
On the drive shaft side, a fluid seal is installed on the
pump housing. A seal between the pump housing and
the cover rely on a specially-shaped seal ring.
MULTI-WAY VALVE AND PRIORITY SPOOL
The 4-disk multi-way valve consists of a six-plate valve
body, four spool valves, one relief valve, and one
priority spool. The six-plate valve body is assembled
using three stub bolts and nuts. The tilt spool valves
are fitted with a tilt auto-locking valve.
1. SAFETY
OVERFLOW VALVE
2. LIFTING SPOOL
VALVE
3. TILT SPOOL VALVE
4. AUX. SPOOL
VALVE
5. PORT (OIL OUTLET)
6. BYPASS VALVE
(CONNECTED WITH
STEERING GEAR)
7. PORT (OIL INLET)
Figure 37. Multi-way Valve
Operation of Spool Valve
The Tilt Spool Valve is described below. All other spool
valves operate, and are repaired in a similar fashion.
Neutral Position
In the NEUTRAL position, the high-pressure fluid is
drained from the pump and returns to the fluid tank.
See Figure 38.
Hydraulic System 8000 YRM 2199
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