A combiner does three jobs.
- Wait to receive an item through input port 1.
- Move items into first entered item through input ports larger than one by recipe table.
- Setup and process the item.
On Exit there is an option how you move the content of first item out:
- Pack: just release the first entered item.
- Join: delete the content of first entered item.
- Batch: release first the content and at last the first entered item.
Yes, it is possible to do the same with a crane.
- unload an item that would be unloaded through input port number one,
- let the item stay until process stacking is complete,
- move or unload items by recipe table into the first unloaded item and
- delay for a process time interval.
- Finally you execute a node that does the options join or batch.