Patent ID: 6283834
Filing Date: 2001-09-04
Classification: B24B

Abstract:
A diaphragm-support disc for a polishing machine of the type in which a work piece to be polished is sandwiched between a radial front face of a diaphragm and a polishing surface or cloth, the diaphragm being extended across a radial front face of the disc and wrapped around a peripheral edge of the radial front face of the disc, and a radial rear face of the diaphragm being subjected to pressure from a fluid, said diaphragm-support disc comprising:a main annular part projecting from the radial front face of the disc, the main annular part being located in a peripheral region of the radial front face of the disc and a predetermined distance from the peripheral edge of the radial front face of the disc; anda secondary annular part projecting from the radial front face of the disc, the secondary annular part being located on the peripheral edge of the radial front face of the disc,wherein during polishing of the workpiece, the main annular part physically contacts the diaphragm so as to press the diaphragm against the work piece and press the work piece onto the polishing surface or cloth by an axial displacement of the disc with respect to the polishing surface or cloth, andthe secondary annular part does not extend as far from the radial front face of the disc as the main annular part, and the main annular part is located some distance from the secondary annular part.