Method and apparatus for marking workpieces

Abstract

A method and an apparatus are provided for marking a sheet-shaped workpiece using a marking tool. The marking tool is mounted in a punch holder of a punch press and a counter-support is fixed in place on a side opposite of a marking surface of the workpiece to be marked. The surface of the workpiece is marked by displacing the workpiece in its plane while engaging the marking tool with the workpiece. In one form, a support roller provides counter-support. In another form, an elastic element is cooperatively associated with the punch stroke of the punch press to translate an exactly defined contact pressure force between the tool tip and the workpiece to be marked.

1 . An device for marking a sheet-shaped workpiece, comprising: 
 a tool holder having a support and adapted to be mounted in a punch press and constructed to receive at its upper end a force of a punch press to move the support downwardly,    a marking tool mounted in the support and having a sheet marking tip at its lower end, and    an elastic element operatively mounted in the device between the support and the marking tool, the support being movable downwardly by a force received from a punching press, until the marking tip engages the workpiece, after which further downward movement of the support compresses the elastic element to cause the marking tip to increase its force against the workpiece.    
   
   
       2 . The device of  claim 1 , including a pressure plate located in the support and positioned to receive the force of the elastic element and transfer such force to the marking tool.  
   
   
       3 . The device of  claim 2 , including a guide insert mounted at the lower end of the guide support and a tool shaft extending from the pressure plate, through the guide insert to the marking tip.  
   
   
       4 . The device of  claim 1 , including a driving head positioned to receive a force of a punching press and transfer such force to the support.  
   
   
       5 . The device of  claim 4 , including a guide bushing positioned to transfer a force of a punching press from the driving head to the support.  
   
   
       6 . The device of  claim 1 , including a counter-support located on the opposite side of the workpiece from the marking tip.  
   
   
       7 . The device of  claim 1 , wherein the counter-support includes at least one rotatable support roller or support ball.  
   
   
       8 . The device of  claim 1 , in combination with a punching press in which the device is disposed.  
   
   
       9 . The device of  claim 1 , wherein the elastic element is a metallic spring.  
   
   
       10 . The device of  claim 1 , wherein the elastic element is a pneumatic spring.  
   
   
       11 . The device of  claim 1 , wherein the elastic element is a hydraulic spring.  
   
   
       12 . The device of  claim 1 , wherein the marking tip is selected from the group consisting of diamond, boron nitride, or a hard alloy.  
   
   
       13 . The device of  claim 1 , wherein the support is adjustable to vary the position of the marking tip and/or the pre-stress of the elastic element.  
   
   
       14 . The device of  claim 1 , wherein the marking tool comprises an ink point for writing a marking on the surface of the workpiece.