Block Search
Bu içerik henüz dilinizde mevcut değil.
A tool breaks two hours into a four-hour program. Nobody wants to cut the first two hours again.
Block search starts the program from a block you choose. The problem it has to solve is that everything before that block still happened as far as the program is concerned: a tool was changed, a spindle was started, coolant came on. Jumping straight to block 900 would run it with no tool, no spindle and no coolant.
So the control replays what the skipped region would have set, then approaches the restart point, and only then carries on.
Running a search
Section titled “Running a search”On the BLOCK SEARCH screen:
SEARCHpicks the block to restart from. The control scans the program up to that point and records what it would have set.GO SAFEif you need the tool out of the way first.RESUME, then cycle start. The control replays the setup, approaches, and runs on.
ABORT leaves the search without restarting.
What gets restored
Section titled “What gets restored”Scanning the skipped region collects three things:
| Restored | From |
|---|---|
| the tool | the last tool selected before the target block |
| the spindle speed | the last speed commanded before it |
| every M code | in the order the program had them |
The M codes are re-issued as ordinary blocks. The control does not interpret them: it does not know that one of them means coolant and another means a clamp. That is why a machine-specific M code reaches the PLC exactly as it would have, and an M code that a machine has aliased to a macro expands exactly as it would have in the program.
Speed is restored before the spindle M code, so the spindle starts at the right speed rather than starting slow and being corrected.
The approach
Section titled “The approach”The restart point is the start of the target block, in machine coordinates.
The approach is deliberately shaped so the tool never crosses the part on the way in:
- Z clears first to the machine’s safe height. If the tool is already at or above it, clearing would be a descent and is skipped.
- X and Y traverse at that height.
- Z enters last, down to the restart point.
If there is no restart point, or the machine has no safe height configured, the control approaches nothing and leaves you to position by hand. Traversing XY at an unknown Z is the exact collision the retract exists to prevent, so it will not guess.
What block search does not do
Section titled “What block search does not do”- It does not cut the skipped part. Only the setup is replayed, never the motion. Everything the skipped blocks would have machined is still uncut. Restarting into a finishing pass over material that was never roughed breaks the replacement tool as well.
- It does not know why you stopped. If the tool broke, the datum did not move. But if the part shifted, restarting mid-program cuts the new position with the old numbers.
- It does not replace looking at the program. Read the blocks around the restart point before you resume, especially if the skipped region contained anything the program depends on later.