GB829516A - Grinding machine - Google Patents

Abstract

829,516. Grinding. AUTOFLOW ENGINEERING Ltd. Oct. 6, 1958 [Jan. 1, 1958], No. 24/58. Class 60. A machine for grinding the surface of a workpiece 11 comprises a cam-like abutment 33 which is driven in timed relationship to a relative traverse between the workpiece and grinding head and is arranged so that it initially limits the operation of a piston-and-cylinder device 23 for advancing the table 16 supporting the workpiece to a position wherein the workpiece contacts a grinding wheel 13 and, on its continued rotation, then controls the feed of the workpiece by permitting a continuance of the table advancing operation of the device 23. The workpiece, such as a substantially rectangular block of glass which is to be ground to a convex curvature 10, is supported on the table 16 which is bolted to a shaft 17 rotatably mounted in taper-roller bearings 18, 19 in a sleeve 20 located on a plate 21. The table 16 is rotated by a chain drive 46 from a shaft 38 connected by universal couplings 42, 43 to an electric motor 35 mounted on the plate 21. The sleeve 20, together with the table and its drive and the plate 21, is upwardly movable in a guide 26 by the piston-andcylinder device 23, which movement is limited by a roller 31 mounted on the plate 21 engaging the abutment 33 which is of snail-shape and rotatably mounted in a slide 50 vertically movable by a worm drive 52, 53. The abutment 33 is rotated by a motor or other means in timed relation to the movement about the centroid of the glass block of the head 12. carrying the grinding wheel 13, which is driven by an electric motor 14, to permit further movement of the table by the device 23 to thereby grind the block to the contour 10. Wear of the grinding wheel is compensated by vertical adjustment of the abutment 33 by means of the drive 52, 53, graduations on the slide 50 and its guide 51 permitting accurate setting of the abutment. Coolant and abrasive material is prevented from reaching the bearings of the table by a labyrinth 54, 55, 56 and a plate 57.