Lapping machine

Claim 1

In a lapping machine including a lapping disk having an annular horizontal planar lapping surface rotatable about a central axis, an apparatus for lapping a plurality of workpieces on said lapping surface while simultaneously maintaining such planar lapping surface in a flat condition, such apparatus comprising; A. a bridge member spanning said planar lapping surface and including a plurality of laterally extending arms also extending transversely and generally horizontally above such lapping surface; B. a spindle assembly supported on a respectively associated one of each of said arms for horizontal movement of each such assembly along the length of its respectively associated arm and each such assembly including, I. manually operable means for horizontally varying the position of the assembly along its said associated arm, II. a vertically movable and rotatable spindle, III. a first motor for reciprocatively and vertically moving the lower end of the associated spindle toward and away from said lapping surface, and IV. a variable speed second motor for rotatably driving the associated spindle; and C. a combined workpiece holder and pressure plate attached to the lower end of each said spindle for driven rotation thereby, whereby said spindle assemblies can, in relation to each other, be staggeringly horizontally positioned along the lengths of their respectively associated transverse arms with workpieces disposed between said lapping surface and said combined workpiece holders and pressure plates to thereby define different but radiaLly overlapping paths of rotation of said workpieces about said central axis of said lapping surface, and the rotational speed of the workpieces by each said workpiece holder and pressure plate can be varied to render the speeds of movement of all said workpieces over said lapping surface substantially equal to thereby maintain such lapping surface flat while simultaneously lapping said workpieces.