IAI X-SEL PX, Operation Manual, Page: 341 / 560

313
Part 4 Commands

PACH (Dedicated SCARA command)
Command, declaration
Extension condition
(LD, A, O, AB, OB)
Input condition
(I/O, flag)
Command,
declaration
Operand 1 Operand 2
Output
(Output, flag)
Optional Optional PACH
Palletizing
number
Position
number
PE
Perform arch motion from the current point and move to the palletizing points.
 Move to the palletizing points specified in operand 1, via arch motion.

Movements in the PX/PY-axis directions will begin after rising from the current point to the palletizing
start-point arch trigger. After the Z point specified in operand 2 (as the highest point) is passed and
movements in the PX/PY-axis directions are complete, the axes will pass near the palletizing end-
point arch trigger and reach the calculated palletizing point.

Palletizing arch triggers must have been set using a PTRG command.
(Note) If the specified palletizing setting involves both SCARA and linear movement axes, an
“Error No. 421, SCARA/linear movement axis simultaneous specification error” will
generate.
When setting palletizing where the palletizing points define an arch-motion movement,
make sure all operating axes are SCARA axes.
PCHZ 3
PTRG 11 13
PACH 1 12
* When the operation is resumed after a pause, depending on the position where the operation is
resumed the locus may follow the lines (dotted lines) indicated by asterisks in the diagram for the
composite section from ascent to horizontal movement or from horizontal movement to descent. Be
careful not to cause interference.
Highest point of palletizing arch motion
Position No. 12
* *
* *
Start point
End point
Palletizing No. 1
Palletizing start-point arch trigger
Position No. 11
Palletizing end-point arch trigger
Position No. 13
314
Part 4 Commands

The PZ-axis coordinate of the end point will become the PZ-axis component of the position
coordinates of the palletizing point, if any, plus the palletizing Z-axis offset. If there is no PZ
component, the PZ-axis coordinate of the end point will become the PZ-axis coordinate of the start
point plus the palletizing Z-axis offset. (Normally the offset is added to all palletizing positions, such
as the arch triggers and Z point.)
 An error will generate if the palletizing start-point arch trigger is set below the start point or the
palletizing end-point arch trigger is set below the end point. (Note: Up/down has nothing to do with
+/– on the coordinate system.)

The PZ-axis up direction refers to the direction toward the Z point from the start point (the down
direction refers to the opposite direction), and has nothing to do with the size of coordinate value.
Therefore, be sure to confirm the actual operating direction when using this command.

The PZ-axis will come down after a rise-process command value is output. Therefore, the operation
may follow the locus shown below depending on the settings of palletizing arch-trigger points and Z
point:
Fig. 5
In this case, change the palletizing arch triggers and PZ point to increase the operation efficiency.
 If palletizing composition (PEXT) is set, axes other than the PX, PY and PZ-axes will also be
operated if data is available for such axes. However, the composite axis will start/end operation at
positions above the arch triggers. If the R-axis is set with a PEXT command, R-axis operation will
start and end above the arch triggers.

Executing this command will not increment the palletizing position number by 1.
(Note 1) The PACH command executes PTP operation.
Z point
Palletizing start-point
arch-trigger point
Palletizing start-point
arch-trigger point
Start point
End point
Start point End point
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