Apparatus and method for modifying an edge

Abstract

Edge modifying apparatuses that include a disc chuck, a disc edge modifying unit having an abrasive article support, and a uniform velocity linear oscillation driver coupled to at least one of the disc chuck and the abrasive article support are described. The uniform velocity linear oscillation driver provides a substantially constant velocity for at least 80 % of each half-cycle of oscillation. Methods of modifying the edge of disc using such apparatuses are also described.

1 . An edge modifying apparatus comprising:
 (a) a disc chuck having a disc-mounting surface and a disc chuck axis of rotation;   (b) a disc edge modifying unit comprising an abrasive article support having a support surface and a support axis of rotation; and   (c) a uniform velocity linear oscillation driver coupled to at least one of the disc chuck and the abrasive article support.   
     
     
         2 . The apparatus of  claim 1 , wherein the uniform velocity linear oscillation driver is mechanically coupled to the abrasive article support. 
     
     
         3 . The apparatus of  claim 1 , wherein the uniform velocity linear oscillation driver comprises a cam having a peripheral edge defined by a curve resulting in a substantially constant linear oscillation velocity during at least 80% of each half-cycle of oscillation. 
     
     
         4 . The apparatus of  claim 3 , further comprising a cam follower mechanically coupled to the peripheral edge of the cam, wherein the peripheral edge is defined by a curve resulting in a substantially constant linear oscillation velocity during at least 90% of each half-cycle of oscillation. 
     
     
         5 . The apparatus of  claim 1 , wherein the disc chuck axis of rotation forms an angle of between about 30 degrees and about 75 degrees, inclusive, relative to the support axis of rotation. 
     
     
         6 . The apparatus of  claim 1 , wherein the disc chuck axis of rotation and the support axis of rotation are coplanar. 
     
     
         7 . The apparatus of  claim 1 , wherein the disc chuck axis of rotation is tilted by between about 15 degrees and about 50 degrees, inclusive. 
     
     
         8 . The apparatus of  claim 1  further comprising a fixed abrasive article adjacent at least a portion of the support surface. 
     
     
         9 . The apparatus of  claim 1 , wherein the uniform velocity linear oscillation driver comprises at least one of a stepper motor, a screw drive, a magnetic drive, and a linear gear. 
     
     
         10 . The apparatus of  claim 1 , wherein the uniform velocity linear oscillation driver comprises a reversible motor and a control to reverse the direction of the reversible motor. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . A method of modifying the edge of a disc comprising:
 (a) providing an edge modifying apparatus comprising:
 (i) a disc chuck including a disc-mounting surface and a disc chuck axis of rotation; 
 (ii) a disc edge modifying unit comprising an abrasive article support having a support surface and a support axis of rotation; and 
 (iii) a uniform velocity linear oscillation driver coupled to at least one of the disc chuck and the abrasive article support; 
   (b) centering a disc on the disc-mounting surface of the disc chuck;   (c) positioning an edge of the disc relative to a fixed abrasive article adjacent the support surface of the abrasive article support such that at least a portion of the edge of the disc contacts an abrasive surface of the fixed abrasive article;   (d) rotating the disc chuck; and   (e) providing a linear oscillation of the fixed abrasive support surface relative to the disc-mounting surface, wherein the linear oscillation has a substantially constant velocity for at least 80% of each half-cycle of oscillation.   
     
     
         15 . The method of  claim 14 , wherein creating a linear oscillation of the fixed abrasive support surface relative to the disc-mounting surface comprises oscillating the fixed abrasive article support. 
     
     
         16 . The method of  claim 14  further comprising rotating the abrasive article support. 
     
     
         17 . The method of  claim 14 , wherein the uniform velocity linear oscillation driver comprises a cam having a peripheral edge. 
     
     
         18 . The method of  claim 17 , wherein the uniform velocity linear oscillation driver further comprising a cam follower mechanically coupled to the peripheral edge of the cam, and wherein the peripheral edge is defined by a curve resulting in a substantially constant oscillation velocity during at least 90% of each half-cycle of oscillation. 
     
     
         19 . The method of  claim 14 , wherein the uniform velocity linear oscillation driver comprises at least one of a stepper motor, a screw drive, a magnetic drive, and a linear gear. 
     
     
         20 . The method of  claim 14 , wherein the uniform velocity linear oscillation driver comprises a reversible motor and a control to reverse the direction of the reversible motor. 
     
     
         21 . The apparatus of  claim 1 , further comprising a positioning assembly coupled to the disc chuck.