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Figure 92
Phase 5
: in this Phase, once limit switch
c1
is reached, we need to change the Line from
U2
to
U3
. The output
signal coming from the limit switch
c1
corresponds to the pilot signal
S3
of the memory valve, which activates
LineU3
by changing over.
With the removal of
Line U2
, themonostable valve of cylinder
C
assumes the position defined by the spring, the
piston rod/piston changes direction and returns to its negative end position.
U2 * c1
=
S3
=
U3
=
C –
+
+
-
D
+
-
C
+
-
B
-
A
I.C.
a1
c1
U1 * I.C. * b0 =A+
U1 * a1=S2=U2=A-
U2 * a0 =B+
U2 * b1 =C+
U2 * c1=S3=U3=C-
b1
a0
Cil. "A"
Cil. "B"
Cil. "C"
Cil. "D"
a0 a1
b0 b1
c0 c1
d0 d1
b0
a1
a0
c1
b1
I.C.
U1
U2
U3
U1
U2
U3
S1
S3
S2
2 3
5
4 6
1 7 8
1
Fig. 92
Figure 93
Phase 6
:
LineU3
feeds limit switch
c0
which, activated by the return of cylinder
C
operates themain valve of the
cylinder
D
, stroke
D+
is obtained.
U3 * c0
=
D+
+
+
-
D
+
-
C
+
-
B
-
A
a1
c1
b1
a0
c0
U1 * I.C. * b0 =A+
U1 * a1=S2=U2=A-
U2 * a0 =B+
U2 * b1 =C+
U2 * c1=S3=U3=C-
U3 * c0 =D+
I.C.
Cil. "A"
Cil. "B"
Cil. "C"
Cil. "D"
a0 a1
b0 b1
c0 c1
d0 d1
b0
a1
a0
c1
b1
c0
I.C.
U1
U2
U3
U1
U2
U3
S1
S3
S2
2 3 4
6
1 7 8
1
5
Fig. 93
Figure 94
Phase7
: the piston rod/piston of cylinder
D
completes the positive stroke, it reaches and activates limit switch
d1
,
whose output
S1
operates the first memory valve, resetting the cascade, interrupting
Line U3
and reactivating
Line U1
. The interruption of
Line U3
cancels the operation on the monostable valve of cylinder
D
, which, by
repositioning itself, allows the piston rod/piston to complete its negative stroke.
U3 * d1
=
S1
=
U1
=
D –
5
184
CAMOZZI
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CIRCUIT TECHNIQUE