Method for producing reversible blades

Abstract

The invention relates to a method for producing reversible knives (W) with profiled cross section, in particular for a use in chopping machines for wood chipping, composed in cross section of a proximal support part ( 2 ) with at least one fitting means ( 21, 22 ) for fastening the knife (W) in a detachable and displacement-proof manner and on both sides on the support part ( 2 ) a distal chipping region ( 5 ) containing the cutting edges ( 52 ) , wherein a preliminary material ( 1 ) with large longitudinal extension is subjected to a surface processing ( 11 ) and a support profile ( 2 ) is formed therefrom by rolling. In order to economically optimize the property profile of reversible knives it is provided according to the invention that the distal regions ( 23 ) of the support part ( 2 ), worked in an overfilled rolling groove and having a large longitudinal extension, are removed in passage, respectively forming a bonding surface ( 31 ) axially symmetrically in the longitudinal direction, after which respectively one attachment part ( 4 ) of tool steel is attached to these processed surfaces ( 31 ) of the support part ( 2 ) by means of metallic bonding ( 41 ), and from the attachment parts ( 4 ) chipping regions ( 5 ) with respectively one blade region ( 51 ) and one cutting edge ( 52 ) are shaped by chip removal, on which edge regions ( 5 ) a thermal material treatment and subsequently a cutting to length take place to produce reversible knives (W) ready for operation.

1 . A method for producing reversible knives (W) with profiled cross section, in particular for a use in chopping machines for wood chipping, composed in cross section of a proximal support part ( 2 ) with at least one fitting means ( 21 ,  22 ) for fastening the knife (W) in a detachable and displacement-proof manner and on both sides on the support part ( 2 ) a distal chipping region ( 5 ) containing the cutting edges ( 52 ) , wherein a preliminary material ( 1 ) with large longitudinal extension is subjected to a surface processing ( 11 ) and a support profile ( 2 ) is formed therefrom by rolling, characterized in that the distal regions ( 23 ) of the support part ( 2 ), worked in an overfilled rolling groove and having a large longitudinal extension, are removed in passage, respectively forming a bonding surface ( 31 ) axially symmetrically in the longitudinal direction, after which respectively one attachment part ( 4 ) of tool steel is attached to these processed surfaces ( 31 ) of the support part ( 2 ) by means of metallic bonding ( 41 ), and from the attachment parts ( 4 ) chipping regions ( 5 ) with respectively one blade region ( 51 ) and one cutting edge ( 52 ) are shaped by chip removal and/or cold forming, on which edge regions ( 5 ) a thermal material treatment and subsequently a cutting to length take place for reversible knives (W) ready for operation. 
     
     
         2 . The method according to  claim 1 , characterized in that the preliminary material ( 1 ) with large longitudinal extension, after a dimensionally exact processing of the surface thereof and before a rolling to form a support part ( 2 ), is heated by a rapid heating in a period of less than 50 sec., in particular of less than 15 sec., preferably by means of induction heating, in passage to a temperature of less than 900° C. with the proviso that the structure of the material remains in a cubic body-centered atomic structure. 
     
     
         3 . The method according to  claim 1 , characterized in that axially symmetrically distal regions are removed from the shaped support part ( 2 ) during its guidance by the fitting means ( 21 ,  22 ) in passage with the formation of processed flat surfaces ( 31 ), wherein the width of the surfaces is more than 0.9 mm but less than 2.9 mm. 
     
     
         4 . The method according to  claim 1 , characterized in that with a shift in the longitudinal axial direction and with guidance of the support part ( 2 ) by the fitting means ( 21 ,  22 ), this is metallically fixed with attached parts ( 4 ) with a thickness of more than 0.9 mm but less than 2.9 mm and a width of 1.0 mm to 4 mm, preferably by fusion without any additional material, in particular by means of laser welding. 
     
     
         5 . The method according to  claim 1 , characterized in that the attached parts ( 4 ) are further developed by cutting and/or by non-cutting shaping to form chipping regions ( 5 ) essentially triangular in cross section with cutting edges ( 52 ). 
     
     
         6 . The method according to  claim 1 , characterized in that the blade regions ( 51 ) with the cutting edges ( 52 ) on the chipping region ( 5 ) of the support part ( 2 ) after a final machining to the axially symmetrical representation of the cutting edges ( 52 ) in passage are subjected to a material heat treating by quenching and tempering the blade region ( 51 ) of tool steel. 
     
     
         7 . The method according to  claim 1 , characterized in that a support part ( 2 ) with great longitudinal extension after shaping of the distal chipping and blade regions ( 5 ,  51 ) and a thermal quenching and tempering of the dressed cutting edges ( 52 ) is cut to length and finally formed to produce reversible knives ready for use.