User's Manual

4-36
CHAPTER 4 Adjustment
3-4-2-4 Adjusting the Z-axis machine reference
The stroke end method is employed on the YK180X 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 the Z-axis upper-end mechanical stopper is at the position shown
in Fig. 4-15.
If not, loosen the bolt and adjust the mechanical stopper to the specified
position. Retighten the bolt to a torque of 20kgfcm (2.0Nm).
2) Check that no one is inside the safeguard enclosure, and then turn on the
controller.
3) Place a sign indicating the robot is being adjusted, to keep others from oper-
ating the controller or operation panel.
4) 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.
5) 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 (26 to 74%), the distance between the upper end urethane damper and
the lower end of the spline nut is approximately 5mm.
6) If the machine reference value is not within the tolerance range, perform the
following steps.
7) Turn off the controller.
8) Enter the safeguard enclosure.