User Guide

4-27
CHAPTER 4 Adjustment
3-4-1-5 Adjusting the Z-axis machine reference
The stroke end method is employed on the YK120X series robots for the absolute
reset of the Z-axis.
The origin position of the Z-axis is fixed at the upper end of the Z-axis stroke, and
it cannot be changed.
The machine reference is factory-adjusted at shipment, and readjustment is not
necessary for normal use.
The readjustment in the following procedure is required, however, if the machine
reference exceeds the tolerance range (26 to 74) of the absolute reset for any
reason.
!
CAUTION
The origin position may change when the machine reference amount is ad-
justed.
The point data must be reset after adjusting the machine reference.
1) Check that no one is inside the safeguard enclosure, and then turn on the
controller.
2) Place a sign indicating the robot is being adjusted, to keep others from oper-
ating the controller or operation panel.
3) Perform the Z-axis absolute reset.
To perform the Z-axis absolute reset, see "3-3-3 Stroke end method (Z-axis)"
in Chapter 4.
4) Turn off the controller.
5) Enter the safeguard enclosure.
6) Remove the Y-axis upper cover.
To remove the covers, see "7 Removing the Robot Covers" in Chapter 4.
Place the upper cover on the robot base (pedestal) side with the machine
harness still connected.
7) Confirm that the Z-axis rising end mechanical stopper is at the position shown
in Fig. 4-11 (a).
If not at that position, loosen the bolt and fix the stopper at the position shown
in the drawing. The tightening torque is 4.4kgfcm (0.43Nm).
Carry out steps 1) to 3) after fixing the mechanical stopper again.
After completing absolute reset, check to see if the machine reference value
is within the tolerance range for absolute reset. When within the tolerance
range, turn off the controller power switch and reinstall the Y-axis upper cover
to complete the work.