Near-Point Dog Method - Mitsubishi Electric MELSEC iQ-F Series FX5 User Manual

Near-point dog method

The following shows an operation overview of the near-point dog method, one of the OPR methods.
Operation chart
Machine OPR start
([Cd.184] Positioning start signal)
OPR request flag
([Md.31] Status: b3)
OPR complete flag
([Md.31] Status: b4)
Deviation counter clear output
[Md.26] Axis operation status
[Md.34] Movement amount
after near-point dog ON
[Md.20] Current feed value
[Md.21] Machine feed value
1.
The machine OPR is started. (The machine starts accelerating according to the setting of "[Pr.51] OPR acceleration time
selection" in the direction specified in "[Pr.44] OPR direction", and moves at the speed set in "[Pr.46] OPR speed" when
the acceleration is completed.)
2.
When the on state of the near-point dog is detected, the machine starts decelerating.
3.
The machine decelerates to the speed set in [Pr.47] Creep speed and moves at the creep speed after that. (During the
deceleration, the near-point dog must be ON. Otherwise a deceleration stop will occur.)
4.
After the near-point dog turns OFF and at the first input of zero signals, the positioning module stops outputting pulses
and outputs "Deviation counter clear output" to the drive unit. (Deviation counter clear signal output time is set in [Pr.55].)
5.
After "Deviation counter clear" output finishes, the OPR complete flag ([Md.31] Status: b4) turns OFF→ON, and the OPR
request flag ([Md.31] Status: b3) turns ON→OFF.
Restrictions
A pulse generator with a zero signal is required. When using a pulse generator without a zero signal, produce a zero signal
using an external signal.
8 OPR CONTROL
76
8.2 Machine OPR
V
[Pr.46] OPR speed
1.
OFF
Near-point dog
Zero signal
ON
OFF
ON
OFF
OFF
Standby OPR
0
Not set
Store traveled value
Not set
Deceleration using near-point dog ON
[Pr.47] Creep speed
t
2. 3. 4. 5.
[Md.34] Movement amount after near-point dog ON
ON
Adjust so that the near-point dog OFF position
is as close to the 0-point signal HIGH center
as possible. If the near-point dog OFF position
is applied to the 0-point signal, a difference
may occur in the servomotor 1 rotation at the
machine OPR stop position.
Servomotor 1 rotation
ON
[Pr.55] Deviation counter clear signal output time
Standby
Value of *1
OP address
*1