Mitsubishi Electric MELSEC-Q Series - Home Position Return by the Dog Cradle Method

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6 POSITIONING CONTROL
6.23.9 Home position return by the dog cradle method
(1) Dog cradle method
After deceleration stop by the proximity dog ON, if the zero point is passed (zero
pass signal: M2406+20n ON) after traveling to reverse direction and turning the
proximity dog OFF, the deceleration stop is made. And it moves to direction of
home position return again with creep speed and the first zero point after
proximity dog ON is home position in this method.
(2) Home position return by the dog cradle method
Operation of home position return by the dog cradle method for setting the
proximity dog in the home position return direction is shown below.
V
Home position
return direction
ON
Acceleration time Deceleration time
Home position
return speed
Creep speed
Home position
return start
Home position
Proximity dog
The travel value in this range is stored in the monitor
register "travel value after proximity dog ON".
The travel value in this range is stored in the monitor
register "home position return re-travel value".
Zero point
1) It travels to preset direction of home
position return with the home position return
speed, and a deceleration stop is made by
the proximity dog ON.
2) After a deceleration stop, it travels to
reverse direction of home position return
with the home position return speed.
3) If the zero point is passed by the proximity
dog OFF, a deceleration stop is made.
4) After a deceleration stop, it travels to
direction of home position return with the
creep speed, the home position return ends
with first zero point after the proximity dog
ON.
1)
4)
3)
2)
Fig. 6.40 Home position return operation by the dog cradle method
(3) Home position return execution
Home position return by the dog cradle method is executed using the servo
program in Section 6.23.19.
(4) Cautions
(a) When home position return retry function is not set, if home position return is
executed again after home position return end, a minor error (error code:
115) will occur, the home position return is not executed.