Mitsubishi Electronics QD75D, QD75P 8.2.5 OPR method (3): Stopper method 2)

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MELSEC-Q
8 OPR CONTROL
8.2.5 OPR method (3): Stopper method 2)
The following shows an operation outline of the "stopper meth od 2 )" OPR met h od.
Operation chart
1)
The machine OPR is started.
(The machine begins the acceleration designated in " Pr.51 OPR acceleration time selection", in the dir ection designated in
"Pr.44 OPR direction". It then moves at the " Pr.46 OPR speed" when the acceleration is completed.)
2) The machine begins decelerating when the near-point do g ON is detected.
3) The machine decelerates to the " Pr.47 Creep speed", and subsequently moves at that spee d.
(Torque limiting is required at this time. If the torque is not limited, the servomotor m ay fail in step 4).)
4) The machine presses against the stopper at the creep speed and sto ps.
5)
The pulse output from the QD75 will stop at th e zero signal after the machine stops, outp utting the "deviation counter clear output" to the
drive unit.
(A "deviation counter clear signal output time" is set in the Pr.55 .)
6) After a "deviation counter clear output" is output to the dr i ve uni t, th e O PR co mp le te flag (Md.31 Status: b4) turns from OFF to ON ,
and the OPR request flag ( Md.31 Status: b 3) turns from ON to OFF.
t
ON
OFF
ON
OFF
OFF
ON
0
V
ON
Zero signal
1) 2) 3) 4)
Pr. 46 OPR speed Pr. 47 Creep speed
Stops at stopper
6)
5)
Valid torque limit range
Near-point dog OFF
Torque limit
Machine OPR start
(Positioning start signal)
Deviation counter clear output
Md.26 Axis operation status Standing by
Inconsistent
Inconsistent
In OPR
Value the machine moved is stored
OPR request flag
[ Md.31 Status : b3]
OPR complete flag
[ Md.31 Status : b4]
Md.34 Movement amount
after near-point dog ON
Md.20 Current feed value
Md.21 Machine feed val ue
Standing by
OP address
Pr.55 Deviation counter clear signa
l
output time
Fig. 8.7 Stopper method 2) machine OPR