Process of and Device For Producing Metal Blanks With Different Thicknesses

Abstract

A process of producing metal blanks with different thicknesses from a metallic material includes: producing sheet metal blanks from a band material; changing the temperature of the metal blanks such that, in the blanks, a plurality of regions is produced with different temperatures; rolling the metal blanks having regions with different temperatures in a rolling tool with a roll gap setting, wherein the roll gap setting is kept constant during the operation of rolling the metal blanks, wherein, due to the regions with different temperatures in the sheet metal blanks, portions are produced with different thicknesses. The invention also relates to a suitable device for producing sheet metal blanks with different thicknesses from a metallic material.

What is claimed is: 
     
         1 . A process of producing metal blanks with different thicknesses from a metallic material, comprising the following process stages:
 producing metal blanks from a band material;   changing the temperature of the metal blanks such that a plurality of regions with different temperatures is generated in the metal blanks;   rolling the metal blanks having regions with different temperatures in a rolling tool with a roll gap setting, wherein the roll gap setting is kept constant during the operation of rolling the metal blanks, wherein, due to the regions with different temperatures in the metal blanks, portions are produced with different thicknesses.   
     
     
         2 . A process according to  claim 1 , wherein changing the temperature is effected such that of the regions with different temperatures, at least one region with a constant temperature and/or at least one region with a variable temperature is produced transversely to the rolling direction. 
     
     
         3 . A process according to  claim 1 , wherein changing the temperature in regions of the blanks is achieved by heating or cooling at least one region of the sheet metal blank, more particularly by means of at least one punch which is moved into contact with the metal blank, so that the sheet metal blank at least substantially assumes the temperature of the punch. 
     
     
         4 . A process according to  claim 1 , wherein changing the temperature in regions of the metal blanks is achieved by induction-heating of at least one region of the metal blank, wherein the metal blanks are guided through current-conducting rolls, wherein the regions with different temperatures are generated by varying the power of the current-conducting rolls while the metal blanks are being guided through. 
     
     
         5 . A process according to  claim 1 , wherein changing the temperature in regions of the metal blanks is effected by cooling at least one region of the metal blanks, wherein the metal blanks are heated homogenously to a first temperature prior to being cooled in said at least one region. 
     
     
         6 . A process according to  claim 1 , wherein the metal blanks are heated after having been rolled, more particularly normalized. 
     
     
         7 . A process according to  claim 1 , wherein after having been heated, the metal blanks are hot-formed. 
     
     
         8 . A process according to  claim 1 , wherein the metal blanks are made of steel material and, after changing the temperature, comprise high temperature regions which always comprise a temperature in excess of 500° C., more particularly in excess of 600° C., during the subsequent process stages of rolling and heat treatment up to the stage of being inserted into the forming tool. 
     
     
         9 . A device for producing metal blanks with different thicknesses from a metallic material, for carrying out the process according to  claim 1 , wherein the device comprises: a tool for producing metal blanks from a band material; a temperature-changing tool by means of which regions in the metal blanks can be produced with different temperatures; a rolling tool with a constant roll gap setting, by means of which the metal blanks having different temperature regions can be rolled, so that, due to the different temperature regions, portions with different thicknesses are produced in the metal blanks. 
     
     
         10 . A device according to  claim 9 , wherein the temperature-changing tool comprises at least one punch which can be heated or cooled. 
     
     
         11 . A device according to  claim 10 , wherein the punch comprises temperature controlling means, wherein the temperature controlling means are configured such that the temperature in at least one portion of the punch can be set individually. 
     
     
         12 . A device according to  claim 11 , wherein the punch comprises channels through which a cooling medium can flow in order to cool the punch, wherein, in particular, the through-flow speed of the cooling medium through the channels is controllable. 
     
     
         13 . A device according to  claim 9 , wherein a heat treatment device is arranged downstream the rolling tool and in which the metal blanks can be normalized. 
     
     
         14 . A device according to  claim 13 , wherein, furthermore, it comprises a forming tool which is arranged downstream the heat treatment system, more particularly a hot forming tool in which the metal blanks can be formed and at least partially hardened.