TCM FB-8 Series, Руководство по обслуживанию

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7.1.6 FLOW REGULATOR VALVE
The flow regulator valve is located at the
position as shown in Figure 7.12. It not only
controls the fork lowering speed but works as
a safety device in case of a rupture of the high-
pressure hose.
The oil flowing from the control valve to
the lift cylinders is not controlled, but the oil
returning from the lift cylinders is controlled.
■
Flow regulator valve operation (1- to 3-ton
trucks)
The oil returning from the lift cylinders
flows into the chamber
G
from which it flows
through the chambers D . E , D , C , B and A
back into the control valve.
In this step, the more the oil flow via the
hole C in the piston
④
becomes, the larger the
pressure difference between the front and rear
of the piston becomes.
When the force that pushes the piston
④
,
produced by the pressure differential, is greater
than the spring force
⑦
, the piston
④
moves to the right. The hole D is narrowed by the hole C
to limit the flow rate, and the fork lowering speed is thus controlled.
When the forks are raised, the high-pressure oil from the control valve flows through the
chambers A , B , C , D , E , F , and G into the lift cylinders.
カットバルブ
Fig. 7.12 Mast Piping
This sketch shows the flow regulator valve and related
components for the 1- to 2.5-ton trucks. On 3- to 3.5-ton
trucks, the positions of the flow regulator vale and cut-off
vale are reversed from this sketch.
LIfT CYLINDER
(RIGHT)
LIfT CYLINDER (LEfT)
to OIL TANK
to CONTROL
VALVE
fLOW
REGULATOR
VALVE
CUT-Off VALVE
① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨
自由流
制限流
コントロールバルブ側
リフトシリンダ側
Fig. 7.13 Flow Regulator Valve (1.0- to 3.0-ton Trucks)
1. CASE
2. SPRING
3. BALL
4. PISTON
5. SLEEVE
6. ORIFICE
7. SPRING
8. “O”-RING
9. NIPPLE
Lift cylinder side
Free flow
Regulated
flow
Control valve side
7. HYDRAULIC SYSTEM