Takeuchi TB175W, Руководство по ремонту

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HYDRAULIC UNITS
CONTROL VALVE
IV-36
TB175W
Arm spool switching
1. Dump
Switching the spool (1) of the arm [1] by pressurizing
the port 5Pb2 closes the center bypass passage (2).
The oil supplied from the pump P2 passes through the
center bypass passage (2), tandem check valve (3),
passage (4), and the head of the spool (1), and then
flows into the port 5B2.
Concurrently, part of the oil from the pump P2 flows
through the parallel passages (5), orifice (6), load
check valve (7), and the passage (4), and then enters
the port 5B2.
Switching the spool (1) of the arm [1] causes the spool
(17) of the arm [2] to be switched by the passage (8) to close the center bypass passage (9). The oil sup-
plied from the pump P1 flows through the center
bypass passage (9), passage (10), and check valve
(11), and joins into the port 5B2. Part of the oil from
the pump P1 also, flows through the tandem check
valve (12), the passages (13) and (4), and the head of
the spool of the arm [1], and then joins into the port
5B2. Part of the oil from the orifice (14) of the spool
flows into the tank.
The return oil flows from the port 5A2 through the
head of the spool (1) of the arm [1], and back to the
tank passage (15).
2. Load
L2D216
17
11
10 14
12
9
2
13
15
5
3
7
1
6
8
4
L2D217
1
18
6
4
7 3
5
2
9
13
16
12
14
10
11
17