
B--65245EN/02
3. PERIPHERAL EQUIPMENT CONTROLHANDLING
93
This function moves the machine movable part automatically or manually
in a specified direction to return to a reference position. This method of
reference position return is referred to as the grid method. With this
method, a reference position is determined by an electronic grid position
determined by the one--rotation signal of a position detector.
The deceleration signal for reference position return (*DEC) is placed in
the same position as the high --speed interlock signal (*RILK) on the
built --in DI. So, when the reference position return function with dogs is
used, the high--speed interlock signal (*RILK) cannot be used.
The machine movable part moves by rapid traverse when the jog feed
mode is set, 4 is set as function code, 15 is set as command data 1, and
feed toward a reference position is specified using the feed axis and
direction select signal (+X or --X).
If the deceleration signal for reference position return (*DEC) is set to 0
because a deceleration limit switch is pressed, the feedrate is reduced,
then movement continues at a low constant feedrate.
When an electronic grid position is reached after the deceleration limit
switch is released and the deceleration signal for reference position return
is set to 1 again, feed operation stops. At this time, the reference position
return completion signal (ZPX) is set to 1.
A reference position return direction can be set in a parameter.
The operation described above is shown in the timing chart below.
Grid (one--rotation signal)
Each rotation of the detector
Rapid
traverse rate
Jog feed mode
Function code = 4
Command data 1 = 15
+X/--X
V
*DEC
ZPX
3.5
REFERENCE
POSITION RETURN
FUNCTION WITH
DOGS
3.5.1
Explanation of
Function
3.5.1.1
Reference position
return operation (grid
method)