With bending devices it is frequently desired that there be only a short, straight end piece between the cutting plane and the last bend which the bending head produces.
A bending device is known from EP 0 379 030 B1 (corresponding to DE 690 03 116 T2) in which upstream of the bending head, a cutting device is provided that can be moved in feed direction of the workpiece. It is thus possible to vary the distance between the end of the workpiece produced after cutting and the bending head. However, with this known bending machine, the cutting device, even in its position moved furthest towards the bending head, is still a clear distance from the bending head. As a result, there is in every case a relatively long straight end piece of the workpiece between the cutting point and the bending head.
In DE 10 2009 024 075 A1, a bending device for rod-shaped workpieces is described in which the cutting device mounted upstream of the bending head can likewise be shifted in feed direction of the workpieces. The bending head is attached to the front end of the machine frame, wherein the cutting device can be moved up to a frontmost position in which it is situated immediately in front of the bending head. Although the cutting plane of the cutting device can thus be moved up fairly close to the bending head, in different cases of application this still leads to a straight end piece which turns out to be longer than desired.
In order to still further shorten such relatively short straight end pieces between the last bend in the workpiece and its end, with known bending devices the workpiece has previously been moved backwards via the feeder (or a movable feeder) and the last bend already produced positioned at the cutting unit, in order to make a cut in this position. However, the required reversal of the conveyance direction of the workpiece leads to an undesired reduction in the machine's throughput. In addition, some bending devices also have no movable feeder, in which case it is not even possible to convey the workpiece backwards. Moreover, a rearward conveyance of the workpiece via the feeder is also very problematic when large workpiece diameters are used.
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