TOOL POSITIONING MEANS FOR LENS GRINDER

摘要

A toric lens grinding machine has means for swinging a lens blank past a cup-shaped grinding wheel and in contact therewith, the wheel being mounted on crossed slides. A computer device secured to the wheel carrying slide has a transparent portion overlying an upward beam of light fixed on the machine base. The computer has first dial means marked in diopters for setting an aiming tube so as to be movable along a straight line calculated to determine the base curve of the ground lens. Second dial means marked in diopters are provided for moving the aiming tube along the straight line a calculated distance for determining the cylinder curve of the ground lens. A valve connected to hydraulic motor means for moving the crossed slides has a single lever for moving both slides so that the wheel is moved in a single direction determined by the direction the lever is moved so that the aiming tube and beam of light may be quickly aligned to position the wheel in the machine for grinding the toric lens set on the dials. The aiming tube is illuminated and a mirror overlying the computer device projects images of the tube and light beam on a translucent screen at the side of the machine.