GB1181156A - Improvements in Grinding Machines - Google Patents

Abstract

1,181,156. Grinding. CHURCHILL MACHINE TOOL CO. Ltd. 1 Aug., 1968 [1 Sept., 1967], No. 40058/67. Heading B3D. A machine for grinding crank-pins of large diesel engine crank-shafts comprises a grinding wheel head assembly 6 including a pair of coaxial grinding wheels 7, 8, steady means 3 for supporting a workpiece 4 to be ground, and connecting means 13 between the grinding wheel head assembly and the steady means extending therebetween within the planes of the external lateral surfaces of the grinding wheels to provide a continuous support path lying wholly within said planes. The head assembly 6 is mounted on an infeed slide 11 which has its top and bottom of V-form engaging complementary grooves 12 in a slide 9 and forming hydrostatic bearings therewith. The slide 9 is movable longitudinally on a sub-frame 2 having a narrow web portion 13 connecting the steadies 3 to the head assembly, the steadies supporting a crank-pin 5 to be ground on a crank-shaft 4. The head assembly consists of the wheels 7, 8 which are of annular form and secured by collets 16, 17 to disc arbors 14, 15 having hollow bosses 18, 19, respectively, secured together by a bolt 20. The outer surface of boss 19 forms a hydrostatic bearing with the inner surface of a bearing bush 23 carried by a cranked arm 24 from the in-feed slide 11. A pulley 25 is mounted on the arbor 15 and driven by a belt 26 passing around the cranked arm 24. In another embodiment, the grinding wheels are mounted on a common spindle and a pulley is disposed between the wheels with a hydrostatic bearing between each wheel and the pulley, the bearings being carried by a Y-shaped member. In other embodiments, the hydrostatic bearings are replaced by air bearings.