
B-63783EN-1/01 5.AUTOMATIC OPERATION
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Signal
Retrace signal RVS <G029#4>
[Classification] Input signal
[Function] Directs the control unit to retrace the tool along the path which the tool
was moved in automatic operation (DNC operation and MDI operation
<except memory operation and binary operation>).
[Operation] When RVS turns to "1" while the tool is being moved
forward (hereafter referred to as forward), the tool retraces the tool
path along which it was moved. Note, however, that the tool does not
start retrace immediately after this signal turns to "1" ; the tool starts
retrace after the block performing the current forward operation is
executed. When RVS turns to "0" while retrace is in progress, the tool
switches from retrace operation to re-forward. In this case also, the tool
does not start re-forward to resume machining immediately after this
signal turns to "0" retrace; the tool starts re-forward after retracing all
commands of the block currently subject to retrace.
The movement of a tool can be immediately switched from forward to
retrace or from retrace to re-forward. For this purpose, first turn the
feed hold signal *SP to "0" to stop automatic operation. Then, change
the state of RVS after the automatic operation start in-progress signal
STL turns to "0" and the automatic operation stop state is set. And the
feed hold lamp SPL turns to "1". Next, turn feed hold signal *SP the
automatic operation start signal ST from "1" to "0" to start automatic
operation. Then, the tool can switch its movement to retrace or re-
forward during execution of a block.