Method and smoothing tool for finishing surfaces

Abstract

The invention relates to a method and a smoothing tool for finishing surfaces as well as a workpiece that is machined by smoothing. In accordance with the invention, the surface that is to be machined is smoothed by a shaping process with the aid of a convex smoothing tool.

1 . A method for finishing surfaces, especially bearing recesses, comprising the steps of:
 pre-machining a surface, including fine-boring the surface; and   smoothing the machined surface by partial re-shaping by means of a convex smoothing tool which is pressed against the surface and moved along the same.   
   
   
       2 . A method according to  claim 1 , wherein the smoothing tool is guided approximately along the track of the tool for pre-machining. 
   
   
       3 . A method according to  claim 1 , wherein the smoothing tool is pressed against the surface with a predetermined surface pressure or a predetermined biasing force. 
   
   
       4 . A method according to  claim 1 , wherein the roughness depth after smoothing is less than 1/1000 mm. 
   
   
       5 . A method according to  claim 1 , wherein groove-shaped or slot-shaped recesses are formed in the surface. 
   
   
       6 . A method according to  claim 5 , wherein a circumferential groove having a depth within the micrometer range is formed in the surface. 
   
   
       7 . A method according to  claim 1 , wherein the smoothing tool is operatively connected such that the surface pressure or the biasing force is constantly within a predetermined tolerance range. 
   
   
       8 . A method according to  claim 1  comprising the steps of:
 presetting a pre-machining tool used in the pre-machining step to a theoretical setting;   wherein the pre-machining step is performed until approximately a middle of a tolerance range is reached;   picking up a dimension associated with the pre-machining step and identifying the dimension as a zero dimension in the machine;   transferring the zero dimension to a measuring station and fixing it;   in the case of tool change, picking up the zero dimension from the measuring station and transferring it to the tool in the machine.   
   
   
       9 . A method according to  claim 1 , wherein after the smoothing step the smoothing tool is checked in a measuring station to determine whether the smoothing tool is in position. 
   
   
       10 . A method according to  claim 1 , wherein a deformation of the smoothing tool during smoothing is compensated. 
   
   
       11 . A smoothing tool comprising a convex smoothing member which projects from a rigid tool shaft. 
   
   
       12 . A smoothing tool according to  claim 11 , wherein the smoothing member consists of diamond. 
   
   
       13 . A smoothing tool according to  claim 11 , wherein the tool shaft is clamped in a radially feedable infeed head. 
   
   
       14 . A smoothing tool according to  claim 13 , wherein the infeed head is a diaphragm tilting head. 
   
   
       15 . A smoothing tool according to  claim 11 , comprising at least one pre-machining cutting edge. 
   
   
       16 . A smoothing tool according to  claim 15 , wherein the pre-machining cutting edge is arranged approximately diametrically with respect to the smoothing member. 
   
   
       17 . A smoothing tool according to  claim 11 , wherein the radius of a smoothing surface of the smoothing member is between 2 and 6 mm. 
   
   
       18 . A smoothing tool according to  claim 11 , wherein the smoothing member is fixed to the tool shaft. 
   
   
       19 . A workpiece comprising at least one bearing recess the circumferential wall of which is finished by smoothing. 
   
   
       20 . A workpiece according to  claim 19 , wherein a circumferential groove is formed in a center portion of the circumferential wall. 
   
   
       21 . A workpiece according to  claim 20 , wherein the groove has a depth of less than 20 μm. 
   
   
       22 . A workpiece according to  claim 21 , wherein the depth is between about 1 μm and 5 μm.