GB867259A - Crankshaft lathe and method of operation - Google Patents

Abstract

867,259. Crank-shaft lathes. R.K. LEBLOND MACHINE TOOL CO. April 20, 1959 [Feb. 4, 1959], No. 13323/59. Class 83 (3). A lathe for turning crank-shafts and the like, adaptable to workpieces of different dimensions, has a base for receiving one of a number of tool units each comprising spaced stationary plates, tool-blocks fitted between the plates, master crank-shafts with line bearings journalled in the plates and crank-pin bearings journalled in the tool-blocks, gearing on the ends of the crankshafts outside one of the end-plates, interconnecting the master crank-shafts and the workpiece &c., to give orbital movement to the tools, one of the gears being adjustable to provide the correct drive when setting up the tool unit. The machine is supported by a base 10, Fig. 6, on which brackets 18 are arranged to support an oscillatable work-supporting cradle 12. The latter has rearwardly extending brackets 14 and bearings 20 supported by a shaft 26 arranged parallel to the work-axis. A headstock 48, Fig. 1, is arranged at one end of the cradle with a chuck 46 and a further chuck 62 supported by an adjustable tailstock 60 is arranged at the other end of the cradle. Both chucks are driven by gears 50, 56, respectively, and are fluid-operated by rotary connections 66. One or more steadies 70 are arranged to support the work intermediate its ends. Turning-tools 104, Fig. 6, for the crank-pins are carried in rests 102 forming part of members 100 arranged to carry out an orbital movement under control of two master crank-shafts 106, 108, having the same throw as the crank-shaft to be turned. Gearing is provided at each end of the machine to drive the chucks and master crank-shafts in unison, a motor 118, Fig. 1, being the prime mover. Gear 142 has an outer portion angularly adjustable relative to its hub portion to effect the correct orientation of master crankshafts and workpiece. The approach and feed movement for turning is effected by moving the work cradle by cams 158, Fig. 6, on a shaft 38 carried by the base. This shaft may be driven by a fluid-pressure piston and rack and pinion gears or by a fluid motor 150, Fig. 2, with control switches LS. The tool structure for turning the crank-pins is mounted on a platform 30, Fig. 6, and located by dowels 114. This structure is removable and may be replaced by a simple fixed multi-tool arrangement for turning the crank-shaft webs.