Omron TJ2-MC64 - PROGRAMMING Programming Manual page 150

BASIC commands
/i
• link_position
The absolute position where MOVELINK will start when link_option is
set to 2
Note: The command uses the BASE and AXIS, and unit conversion factors in
a similar way to other MOVE commands.
Note: The "link" axis may move in either direction to drive the output motion.
The link distances specified are always positive.
/i
Example A flying shear that moves at the speed of the material cuts a long sheet of
paper into cards every 160 m. The shear can move up to 1.2 metres, of which
1m is used in this example. The paper distance is measured by an encoder.
The unit conversion factor is set to give units of metres on both axes. Note
that axis 7 is the link axis.
WHILE IN(2)=ON
MOVELINK(0,150,0,0,7) ' dwell (no movement) for 150m
MOVELINK(0.3,0.6,0.6,0,7) ' accelerate to paper speed
MOVELINK(0.7,1.0,0,0.6,7) ' track the paper then decelerate
WAIT LOADED ' wait until acceleration movelink is finished
OP(8,ON) ' activate cutter
MOVELINK(-1.0,8.4,0.5,0.5,7) retract cutter back to start
WAIT LOADED
OP(8,OFF) ' deactivate cutter at end of outward stroke
WEND
In this program, the controller waits for the roll to feed out 150 m in the first
line. After this distance the shear accelerates to match the speed of the paper,
moves at the same speed, and then decelerates to a stop within the 1 m
stroke. This movement is specified using two separate MOVELINK com-
mands. This allows the program to wait for the next move buffer to be clear,
NTYPE=0, which indicates that the acceleration phase is complete. Note that
the distances on the measurement axis (the link distance in each MOVELINK
command), 150, 0.8, 1.0 and 8.2, add up to 160 m. To make sure that the
speed and the positions of the cutter and paper match during the cut process,
the parameters of the MOVELINK command must be correct. The easiest
way to do this is to consider the acceleration, constant speed and decelera-
tion phases separately, and then combine them as required, according to
these 2 rules:
PROGRAMMING MANUAL
fig. 42
LEAD SCREW
SERVO MOTOR
(AXIS 0)
ENCODER (AXIS 7)
144