Machine for producing parts having skew surfaces of predetermined configuration

Claim 1

In an apparatus for abrading a surface on a workpiece, the apparatus including an endless abrasive belt which has essentially inelastic circumferential length, deformable elastic transverse width and an abrasive outer surface, a base for holding said workpiece and supporting said endless belt, a support movably mounted on said base for maintaining said belt in tension, first drive means for driving said belt circumferentially, and second drive means for moving said support and thereby moving said belt into engagement with said workpiece, the improvement wherein said support comprises: a plurality of frames generally aligned and mounted on said support, each frame having opposite ends, a first set of similar cylindrical shaping rollers, one rotatably mounted on one end of each frame, a second set of similar cylindrical rollers, one rotatably mounted on the opposite end of each frame, the axes of said rollers being parallel, the distance between the axes of the two rollers on each frame being the same, each frame having a longitudinal axis extending between the axes of the two rollers thereon, a first belt circumscribing said two sets of rollers, said first belt having essentially inelastic circumferential length and deformable elastic transverse width, said frames being aligned with their longitudinal axes generally coplanar, each frame being movable in the direction of its longitudinal axis relative to said support and to the other frames, whereby the peripheral edges of the adjacent shaping rollers define (a) a profile curve corresponding to the relative moved position of said frames and (b) a straight cylindrical surface when the axes of these rollers are coincident and the portion of said first belt that engages said first set of rollers being deformed according to said profile curves, said abrasive belt being caused to circumscribe at least the portion of said first belt which engages said first set of rollers, said belts being driven by said first drive means, and said abrasive belt being deformed similarly as said first belt, said second drive means adapted to move said frames selectively to create a selected profile curve in said abrasive belt for engaging said workpiece.