Corrugated insert cutting apparatus and method

Abstract

An insert cutting apparatus useable in a production line for producing tubes from shaped sheet-metal strips includes an upper die having a first row of punches, and a lower die having a second row of punches. The first and second rows of punches can form predetermined breaking points in at least one of the shaped sheet-metal strips, and the first and second rows of punches can alternate, so that two punches of the first row of punches have a punch of the second row of punches therebetween.

1 .- 9 . (canceled) 
     
     
         10 . A device useable as part of a production line for producing tubes from shaped sheet-metal strips, the device comprising:
 an upper die having a first row of punches; and   a lower die having a second row of punches;   wherein the first and second rows of punches form predetermined breaking points in at least one of the shaped sheet-metal strips, and   wherein a punch of the second row of punches engages between two punches of the first row of punches.   
     
     
         11 . The device according to  claim 10 , wherein the predetermined breaking points comprise perforations. 
     
     
         12 . The device according to  claim 10 , wherein at least one of the shaped sheet-metal strips has a transverse corrugation defining a plurality of wave crests and wave troughs, and wherein the first row of punches acts in the wave crests and the second row of punches acts in the wave troughs. 
     
     
         13 . The device according to  claim 10 , wherein the two punches of the first row of punches each include a piercing tool. 
     
     
         14 . The device according to  claim 13 , wherein the piercing tool includes a perforation needle. 
     
     
         15 . The device according to  claim 13 , wherein the punch of the second row of punches includes a piercing tool. 
     
     
         16 . The device according to  claim 15 , wherein the piercing tool includes a perforation needle. 
     
     
         17 . The device according to  claim 15 , wherein the piercing tools of the two punches of the first row of punches are spaced apart a first distance, such that the piercing tools of the two punches of the first row of punches have the piercing tool of the punch of the first row of punches therebetween. 
     
     
         18 . The device according to  claim 15 , wherein at least one of the shaped sheet-metal strips has a transverse corrugation defining a plurality of wave troughs and wave crests, and wherein the piercing tools of the first row of punches pierce the wave troughs and the piercing tool of the second row of punches pierces the wave crests. 
     
     
         19 . The device according to  claim 10 , wherein the upper die includes a first roll and the lower die includes a second roll. 
     
     
         20 . The device according to  claim 19 , wherein the first roller defines an outer surface, the first row of punches extending across the outer surface, such that rotation of the first roller moves the first row of punches into and out of engagement with the at least one the shaped sheet metal strips. 
     
     
         21 . A production line for producing tubes from a first shaped endless sheet-metal strip, and a second shaped endless sheet-metal strip, the production line comprising:
 a first device including
 an upper die having a first row of punches; and 
 a lower die having a second row of punches; 
 wherein the first and second rows of punches form predetermined breaking points in the first shaped sheet-metal strip, and 
 wherein a punch of the second row of punches engages between two punches of the first row of punches; 
   a second device positioned at a common location along the production line with the first device, the second device operable to form predetermined breaking points in the second shaped endless sheet-metal strip;   a first section upstream of the first device and the second device, the first section operable to shape the first and second shaped endless sheet-metal strips; and   a second section downstream of the first device and the second device, the second section operable to combine the first and second shaped endless sheet-metal strips,   wherein the first device and the second device work simultaneously to form the predetermined breaking points.   
     
     
         22 . The device according to  claim 21 , wherein the predetermined breaking points comprise perforations. 
     
     
         23 . A device useable as part of a production line for producing tubes from shaped sheet-metal strips, the device comprising:
 an upper die having a first wave shape; and   a lower die having a second wave shape,   wherein at least one of the shaped sheet-metal strips has a transverse corrugation substantially matching the first wave shape and the second wave shape, and   wherein the upper die and the lower die produce predetermined breaking points in at least one of the shaped sheet-metal strips in the transverse corrugation without the corrugation being damaged.   
     
     
         24 . The device according to  claim 23 , wherein the predetermined breaking points comprise perforations. 
     
     
         25 . The device according to  claim 23 , wherein the upper die includes a knife and the lower die includes a roller. 
     
     
         26 . A method for producing tubes on a production line having rolls, the method comprising:
 shaping sheet-metal strips;   combining the sheet-metal strips to form a tube;   after shaping and combining, forming predetermined breaking points in the tube by contacting a first side of the tube with at least two punches from a first row of punches and contacting a second side of the tube with at least one punch from a second row of punches, wherein the at least two punches of the first row of punches have the at least one punch from the second row of punches therebetween.   
     
     
         27 . The method according to  claim 26 , further comprising severing individual tubes from the tube, wherein the tubes are severed along the predetermined breaking points. 
     
     
         28 . The method according to  claim 26 , wherein forming predetermined breaking points including forming perforations. 
     
     
         29 . The method according to  claim 26 , wherein contacting the tube first side includes inserting the two punches into respective wave troughs of the tube and wherein contacting the tube second side includes inserting the one punches into a wave crest of the tube.