Takeuchi TB175W, Руководство по ремонту

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HYDRAULIC UNITS
CONTROL VALVE
IV-33
TB175W
Independent Operation
Travel spool switching
Switching the spool (1) on the right travel lever closes
the center bypass passage (2), and the oil supplied
from the pump P1 passes through the center bypass
passage (2) and bridge passage (3), and flows into the
port 4A1. The return oil flows from the port 4B1
through the head of the spool (1) and back to the tank
passage (4).
Switching the spool (5) on the left travel lever allows the oil supplied from the pump P2 to pass through the
parallel passages (6), the head of straight travel spool
(7), the passages (8) and (9), and to flow into the port
5A5. The return oil flows from the port 5B5 to the tank
passage (4). Part of the oil from the pump P2 passes
through the orifice (10), raises the poppet (11), passes
through the passage (3), and flows into the port 5A5.
Bucket spool switching
Switching the spool (1) by pressurizing the port 4Pa2
closes the center bypass passage (2). The oil supplied
from the pump P1 raises the parallel passages (3) and
the load check valve (4). Then the oil flows through
the passage (5) and the head of the spool (1), and
enters the port 4A2. The return oil flows from the port
4B2 through the head of the spool (1), and back to the tank passage (6). Also, part of the oil is supplied from
the orifice (7) to the left travel section, enabling
concurrent operations of the buckets during right and
left travel operations.
L3D210
7
2
6
8
1
3
2
4
P2
5
9
10
11
5Pb4
4Pb2
5Pa4
4Pa2
4Pa2
5A4 5B4
4A2 4B2
2 3
4
5
7
6
1
L3D211