SMC Networks XGT312-50336 Series, Operation Manual

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3-2 Operation
Figure 1A and B are front view of a slit valve. In these figures, the slit valve closes an opening
(slit)
○
23
which transfers workload and a gate
②
(seal material
③
) does not clamp (seal) a
seating face
⑲
.
In Figure 2A, the slit valve opens and makes the slit
○
23
able to transfer workload.
Figure 2B shows the condition same as Figure 1B and Figure 2C, that
’s, the gate ②
clamps
and seals the seating face
⑲
by the seal
③
.
3-2-1 Overall construction
In Figure 1A and 1B, a piston rod
⑧
integrated with a piston
○
26
and a roller block
⑨
are
integrated and held to an actuating base
○
22
. And a shaft
⑱
fixed to these components and a
lever
⑫
are separated away by force of spring
⑬
. On the other hand, since the lever is bound
by a plate
○
27
fixed to the roller block
⑨
, the shaft
⑱
and the roller block
⑨
can be moved up
and down simultaneously by action of spring
⑬
.
When the shaft
⑱
moves up and down, axial seal between a body
○
21
and outside is realized
by O-rings
⑤
and
⑥
and a bellows
⑦
. And fixing seal between the bonnet ASSY and the
body
○
21
is realized by an O-ring
④
.
3-2-2 Closing gate (Figure 2A to Figure 2B)
The roller block
⑨
integrated with the piston rod
⑧
moves up when pressure is applied to
“CLOSE” side of pressure piping (in other words, pressure is exhausted from “OPEN” side of
pressure piping). On the other hand, although the lever
⑫
, the shaft
⑱
and the gate
②
continue to move up because the roller block
⑨
pushes the shaft
⑱
integrated with the lever
⑫
by force of spring
⑬
, a roller bearing A
⑯
gets into an U-shaped fulcrum groove
⑰
, stops
and closes the slit
○
23
of the body
○
21
.
In Figure 2B, a cam groove
⑩
of the roller block
⑨
and a roller bearing B
⑪
guides the
movement in lateral direction.
Further, the guide groove
⑮
of the plate
○
27
held to the roller block
⑨
and the guide pin
⑭
held to the lever
⑫
are also guiding the lateral movement.
On the other hand, the movement in vertical direction is fixed by constant distance between the
lever
⑫
and the roller block
⑨
. The distance is kept constant by the roller bearing B
⑪
and the
plate
○
27
, which are clamped by spring
⑬
after touching each other. These mechanism to guide
and fix the movement makes the lever
⑫
, the shaft
⑱
and the gate
②
able to move up and
down stably from the gate open position shown in Figure 2A to the gate close position shown in
Figure 2B.