Flanging with a leading and following flanging die

1. A flanging device for beading a flanging web of a component part around a flanging edge, said flanging device comprising:

a) a tool head;

b) a first flanging die and a second flanging die which the tool head bears, simultaneously situated in a processing position, and one of which is arranged following the other in a processing direction;

c) a bearing unit which mounts the first flanging die and is mounted by the tool head such that the bearing unit can be moved in a transverse direction relative to the processing direction; and

d) an actuating means which the tool head bears, wherein the bearing unit is chargeable, by means of the actuating means, with a force which acts in the transverse direction;

wherein the first flanging die can be advanced by means of the actuating means in the transverse direction towards the flanging web far enough that the first flanging die protrudes beyond the second flanging die and can be moved back in the transverse direction far enough from the flanging web that it is short of the second flanging die.

2. The flanging device according to claim 1 further comprising a guide which guides the bearing unit on the tool head in the transverse direction.

3. The flanging device according to claim 1 , wherein the flanging die which is arranged as following is a finishing flanging roller for completely beading the flanging web.

4. The flanging device according to claim 1 , wherein the first and second flanging dies are fixable relative to each other on the tool head with respect to a plurality of degrees of freedom of movement.

5. The flanging device according to claim 1 , wherein the second flanging die is supported on the tool head via a force measuring means.

6. The flanging device according to claim 1 , wherein the first flanging die can be moved transverse to the flanging edge relative to the second flanging die, following the contour of the flanging edge, in order to compensate for a curve in the flanging edge.

7. The flanging device according to claim 1 , wherein the first flanging die is arranged following the second flanging die.

8. The flanging device according to claim 1 , wherein the second flanging die is arranged following the first flanging die.

9. The flanging device according to claim 1 wherein the tool head bears an actuating means, by means of which the bearing unit can be charged transverse to the flanging edge with a force which causes a transverse movement of the bearing unit relative to the second flanging die.

10. The flanging device according to claim 1 wherein a guiding member is arranged on the bearing unit, for a guiding contact with a guiding curve, wherein in the guiding contact of the guiding member, the bearing unit is moved in the transverse direction, following the contour of the flanging edge, and the bearing unit mounts the first flanging die such that it can be moved transversely together with the guiding member.

11. The flanging device according to any claim 1 , wherein the tool head mounts the bearing unit such that it can be moved transversely counter to a restoring force.

12. The flanging device according to claim 1 , wherein the bearing unit is pneumatically supported on the tool head.

13. The flanging device according to claim 1 wherein the tool head mounts the bearing unit such that it can be moved parallel to or angularly to a pressure which the first flanging die exerts on the flanging web during beading.

14. The flanging device according to claim 1 , wherein at least one of the flanging dies is a flanging roller.

15. The flanging device according to claim 1 wherein the transverse direction has at least a direction component in common with a rotational axis of one of the flanging dies which is formed as a flanging roller or with an axis pointing at a right angle to the rotational axis.

16. The flanging device according to claim 1 wherein the flanging device is used for hemming on a vehicle part

17. The flanging device according to claim 1 , wherein the force is constant.

18. The flanging device according to claim 1 , wherein the force is adjustable.

19. The flanging device according to claim 4 , wherein the first and second flanging dies are fixable relative to each other at an inclination which is invariable at least during flanging.

20. The flanging device according to claim 11 , wherein the restoring force is an elasticity force.

21. The flanging device according to claim 16 , wherein the flanging device is used for roll-hemming on a vehicle part.

22. A method for beading a flanging web of a component part around a flanging edge, comprising:

a) moving a tool head, which bears a leading flanging die and a following flanging die, along the flanging edge in a processing run, wherein the tool head bears one of the flanging dies such that it can be moved transverse to the flanging edge relative to the other flanging die;

b) beading the flanging web with the leading flanging die; and

c) further beading the flanging web with the following flanging die in the same processing run;

wherein a corner region of the flanging edge is passed over repeatedly, by reversing the processing direction, and in a first pass, the following flanging die is lifted off the flanging web and in a subsequent, second pass, the leading flanging die is lifted off the flanging web, while in each pass, the other flanging die in each case beads the flanging web.

23. The method according to claim 22 , wherein, during beading, at least one of the flanging dies spring-deflects relative to the other in a direction which is transverse to the flanging edge and also angular or at least substantially parallel to a pressure which the spring-deflecting flanging die exerts on the flanging web during beading.

24. The method according to claim 22 , wherein the component part is accommodated by a component part receptacle which absorbs a pressure exerted by the flanging dies.

25. The method according to claim 22 , wherein at least one of the flanging dies acts on the flanging web with a constant pressure.