Home Position Return - Mitsubishi Electric Q172CPU Programming Manual

8 AUXILIARY AND APPLIED FUNCTIONS

8.5 Home Position Return

Home position return methods
Proximity dog type 1
Proximity dog type
Proximity dog type 2
Count type 1
Count type
Count type 2
Count type 3
Data set type 1
Data set type
Data set type 2
Dog cradle type
Stopper type 1
Stopper type
Stopper type 2
Limit switch combined type
(1) Use the home position return at the power supply ON and other times where
confirmation of axis is at the machine home position is required.
(2) The following six methods for home position return are shown below.
• Proximity dog type
• Count type
• Data set type
• Dog cradle type
• Stopper type
• Limit switch combined type
(3) The home position return data must be set for each axis to execute the home
position return.
(4) Select the optimal home position return method for the system configuration and
applications with reference to the following.
Contents
• Home position is zero point of
servomotor.
• When the proximity dog is ON, it
cannot be started.
• Home position is zero point of
servomotor.
• When the proximity dog is ON, it
can be started.
• Home position is zero point of
servomotor.
• Zero point is not used in the home
position return.
• Home position is zero point of
servomotor.
• Home position is command
position of Motion CPU.
• Home position is real position of
servomotor.
• Home position is zero point of
servomotor immediately after the
proximity dog signal ON.
• Home position is position which
stopped the machine by the
stopper.
• Proximity dog is used.
• Home position is position which
stopped the machine by the
stopper.
• Proximity dog is not used.
• Home position is zero point of
servomotor.
• Proximity dog is not used.
• External limit switch is surely used.
• It is used in the system which can surely pass a zero point
from the home position return start to proximity dog ON
OFF.
• This method is valid when the stroke range is short and
"proximity dog type 1" cannot be used.
• It is used in the system which can surely pass a zero point
from the home position return start to point of travel
distance set as "travel value after proximity dog ON".
• This method is used when the proximity dog is near the
stroke end and the stroke range is narrow.
• This method is valid when the stroke range is short and
"count type 1" cannot be used.
• External input signals such as dog signal are not set in
this absolute position system.
• This method is valid for the data set independent of a
deviation counter value.
• External input signals such as dog signal are not set in
this absolute position system.
• It is easy to set the position of proximity dog, because the
proximity dog is set near the position made to the home
position.
• This method is valid to improve home position accuracy in
order to make the home position for the position which
stopped the machine by the stopper.
• It is used in the system that the proximity dog signal
cannot be used and only external limit switch can be
used.
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Applications