Method for extruding a profile or a similar billet from a bolt or bar and corresponding device

Abstract

A method for extruding a profile or a similar billet from a bolt or bar that is guided in a recipient bore of a recipient and that is extruded by an extrusion die through a shaping section of a shaping tool. Once the front face of the bar is placed on the rear surface of a preceding bar, air or similar flowing agents present on the surfaces are discharged during pressure build-up in an approximately radial relation together with the contaminations that are present in detached form on the transversal bur surface. During pressure build-up, parts of the transversal burs are radially displaced; the displaced parts of the traversal bur surface are discharged on the periphery in an approximately radial relation before the bar enters the shaping tool. To achieve this, a welding chamber or pre-chamber is disposed in the direction of extrusion (x) in a gap that can be adjusted between the recipient and the shaping tool. The chamber is provided with at least one lateral opening or discharge channel through which the displaced parts of the transversal bur are discharged.

1 - 19 . (cancelled)  
     
     
         20 . A process for extrusion molding a profile from a plurality of bars, comprising the steps of: 
 providing a holder ( 14 ) having a receiver bore ( 16 );    providing a molding tool ( 38 ) downstream, with respect to the extrusion direction (x), of the holder, wherein the molding tool includes a mold cross section ( 46 );    feeding at least a first ( 30 ) and a second ( 30   a ) bar axially to the mold cross section wherein the rear face ( 32   a ) of the first feed bar and the front face ( 34   a ) of the second feed bar are brought into contact upstream of the mold cross section resulting in a pressure build-up at the contacting faces of the first and the second bar; and    removing radially fluid media and contaminants from the contacting faces during pressure build-up.    
     
     
         21 . A process according to  claim 20 , wherein the contacting faces form a transverse extrusion seam and, on pressure build-up, parts of the transverse extrusion seam are displaced radially.  
     
     
         22 . A process according to  claim 21 , wherein the displaced parts of the transverse extrusion seam are discharged approximately radially at the periphery before entry into the molding tool.  
     
     
         23 . A process according to  claim 22 , wherein the displaced parts form at least one radial billet ( 31 ) which is discharged approximately radially.  
     
     
         24 . A process according to  claim 23 , wherein the radial billet ( 31 ) is cut away and its flow path ( 72 ) closed.  
     
     
         25 . A process according to  claim 24 , wherein the radial billet ( 31 ) is cut away prior to extruding in the molding tool.  
     
     
         26 . A process according to  claim 20 , wherein the extrusion process is performed under air exclusion.  
     
     
         27 . A process according to  claim 26 , wherein the radial billet ( 31 ) is expelled through a radial discharge channel ( 72 ).  
     
     
         28 . A device for extrusion molding a profile from a plurality of bars, comprises: 
 a holder ( 14 ) having a receiver bore ( 16 ) for receiving the bars;    a molding tool ( 38 ) downstream, with respect to the extrusion direction (x), of the holder;    means for moving one of the holder and the molding tool axially relative to the other in the direction (x) for adjusting a gap (n) therebetween; and    a prechamber ( 70 ) locating the gap (n), said prechamber having a discharge channel ( 72 ).    
     
     
         29 . A device according to  claim 28 , wherein the prechamber ( 70 ) is bordered by a tubular housing ( 68 ) in which is arranged at least one approximately radial discharge channel ( 72 ).  
     
     
         30 . A device according to  claim 29 , wherein the prechamber ( 70 ) has a diameter (i) which corresponds to that of the receiver bore ( 16 ).  
     
     
         31 . A device according to  claim 29 , wherein at least two approximately radial discharge channels are provided on a common axis (Q) in the housing ( 68 ) of the prechamber ( 70 ).  
     
     
         32 . A device according to  claim 28 , wherein a cutter ( 57 ) is arranged outlet opening ( 74 ) of the discharge channel ( 72 ).  
     
     
         33 . A device according to  claim 28 , wherein the prechamber ( 70 ) is firmly connected to one of the receiver ( 14 ) and the molding tool ( 38 ).  
     
     
         34 . A device according to  claim 32 , wherein the prechamber has a plurality of outlet openings ( 74 ) and, allocated to each opening ( 74 ) is a cutting blade ( 59 ) of a cutter ( 57 ).  
     
     
         35 . A device according to  claim 34 , wherein the cutter is a U-shaped cutter ( 57 ) having at least two parallel cutting blades ( 59 ).  
     
     
         36 . A device according to  claim 32 , wherein the cutting blade ( 59 ) of the cutter ( 57 ) span the opening ( 74 ) in a sealing manner.  
     
     
         37 . A device according to  claim 32 , wherein the cutter ( 57 ) is displaceable transverse to the longitudinal axis (A) of one of the receiver bore ( 26 ) and the prechamber ( 70 ).  
     
     
         38 . A device according to  claim 32 , wherein the cutter ( 57 ) is rotatable through 90° about its longitudinal axis (B).