Method for producing a seam using a bending machine, and bending machine configured for this purpose

Abstract

A method for producing a seam on a workpiece made of flat material using a bending machine is disclosed. The bending machine comprises a first clamping jaw, a second clamping jaw that is mounted movably relative to the first clamping jaw and configured to clamp, together with the first clamping jaw, the workpiece in a clamping plane, and a bending unit that is arranged on one of the clamping jaws and has a bending tool, the bending unit being configured to bend a portion of the workpiece by moving the bending tool relative to the associated clamping jaw to form a fold. The method comprises producing a pre-seam on the workpiece such that it is located in an area in front of the clamping jaws, comprising forming a fold, wherein the pre-seam extends at an angle relative to the clamping plane, and changing the angle by displacing the bending tool.

1 . A method for producing a seam on a workpiece made of flat material using a bending machine,
 the bending machine comprising:
 a first clamping jaw; 
 a second clamping jaw that is mounted movably relative to the first clamping jaw and configured to clamp, together with the first clamping jaw, the workpiece in a clamping plane; and 
 a bending unit that is arranged on one of the clamping jaws and has a bending tool, the bending unit being configured to bend a portion of the workpiece by moving the bending tool relative to the associated clamping jaw to form a fold in the workpiece; 
   the method comprising:
 producing a pre-seam on the workpiece such that the workpiece is located in an area in front of the clamping jaws, comprising forming the fold, wherein the pre-seam extends at an angle relative to the clamping plane; and 
 changing the angle by moving the bending tool. 
   
     
     
         2 . The method of  claim 1 , wherein the step of changing the angle is performed by extending the bending tool relative to the associated clamping jaw. 
     
     
         3 . The method of  claim 2 , wherein the bending tool of the bending unit comprises a hook-shaped bending portion having an inner surface and an outer surface, and wherein the step of changing the angle is performed by pressing with the outer surface as the bending tool extends relative to the associated clamping jaw. 
     
     
         4 . The method of  claim 1 , wherein the step of changing the angle is performed by retracting the bending tool relative to the associated clamping jaw. 
     
     
         5 . The method of  claim 4 , wherein the bending tool of the bending unit comprises a hook-shaped bending portion having an inner surface and an outer surface, and wherein the step of changing the angle is performed by pressing with the inner surface as the bending tool extends relative to the associated clamping jaw. 
     
     
         6 . The method of  claim 1 , wherein producing a pre-seam on the workpiece comprises forming a plurality of folds. 
     
     
         7 . The method of  claim 1 , wherein the bending machine further comprises a further bending unit that is arranged on the other clamping jaw and has a further bending tool, and wherein the further bending unit is configured to bend a portion of the workpiece by moving the further bending tool to form a fold, and wherein the step of changing the angle is performed by moving the further bending tool. 
     
     
         8 . The method of  claim 7 , wherein, in the step of producing the pre-seam, the fold is formed by bending with the further bending tool. 
     
     
         9 . The method of  claim 8 , wherein more than one fold is formed by bending with the further bending tool in the step of producing the pre-seam. 
     
     
         10 . The method of  claim 1 , wherein the seam comprises an inclined seam. 
     
     
         11 . The method of  claim 1 , wherein the flat material comprises sheet metal. 
     
     
         12 . The method of  claim 1 , wherein the bending machine comprises a long folding machine. 
     
     
         13 . A bending machine for producing a seam on a workpiece made of flat material, comprising:
 a first clamping jaw;   a second clamping jaw that is mounted movably relative to the first clamping jaw and configured to clamp, together with the first clamping jaw, the workpiece in a clamping plane;   a bending unit that is arranged on the associated clamping jaw and has a bending tool, the bending unit being configured to bend a portion of the workpiece by moving the bending tool relative to the associated clamping jaw to form a fold in the workpiece; and   a control unit configured to:
 produce a pre-seam on the workpiece such that the workpiece is located in an area in front of the clamping jaws, comprising forming the fold, wherein the pre-seam extends at an angle relative to the clamping plane; and 
 change the angle by moving the bending tool. 
   
     
     
         14 . The bending machine of  claim 13 , wherein the bending tool of the bending unit comprises a hook-shaped bending portion having an inner surface and an outer surface. 
     
     
         15 . The bending machine of  claim 13 , further comprising a further bending unit that is arranged on the other clamping jaw and has a further bending tool, and wherein the further bending unit is configured to bend a portion of the workpiece by moving the further bending tool to form a fold. 
     
     
         16 . The bending machine of  claim 13 , wherein the bending machine comprises a long folding machine. 
     
     
         17 . The bending machine of  claim 13 , wherein the seam comprises an inclined seam. 
     
     
         18 . The bending machine of  claim 13 , wherein the flat material comprises sheet metal.