GB624518A - Improvements in or relating to machines for grinding and regrinding crankshafts - Google Patents

Abstract

624,518. Grinding crankshafts. PRINCE, V. J. Sept. 10, 1946, No. 27157. Addition to 556,274. [Class 60] An improvement in or modification of a machine for grinding and regrinding crankshafts, as claimed in the parent Specification, consists in the provision of a rigid control post or support upstanding from the machine bed and adjacent the grinding wheel assembly, with means to couple the assembly to, or release same from the post or support, and a manually controlled feed screw device associated with the post or support and connected to the coupling means, which feed screw serves to effect the adjustment of the position of the grinding wheel axis. The crankshaft is mounted, as in the parent Specification, between a rotated chuck 4a and a tail stock 4 relatively adjustable on a sliding carriage 6 which can be traversed by a rack 8 and pinion 9. A grinding wheel 13 is mounted between the upper ends of parallel side arms 15 pivoted at 17 to the main frame and carrying a grinding wheel driving motor 20 at their lower ends. Adjacent the arms 15 and rigidly mounted on the base is a vertical post 46 to which the grinding wheel support is adapted to be fixed when the main bearings of the crankshaft are to be ground. The post 46 has a head 48, Fig. 3, in which is adjustable, coarsely by a hand-wheel 24 and screw 22 and finely by a hand-wheel 26, worm device and wheel 27, a guide member 23a carrying a ball head 49. Movement of this ball head 49 is transmitted through a telescopic connection 47 to a ball head 60 on the grinding wheel casing so that the position of the grinding wheel is adjusted. The telescopic connection 47 comprises, Fig. 4, a toothed rod 50 coupled to the ball 49 and carried in a sleeve 53 coupled to the ball 60, a trigger 58 being operated to release the ball 60 and a trigger 57 allowing the rod 50 to be adjusted axially with respect to the sleeve 53. For grinding crankpins the connection 47 is uncoupled and, as in the parent Specification, a pair of cranked arms 36a pivoted on the grinding wheel axis contact at their adjustably bifurcated ends the crank pin 44 to be ground so that as the crank pin is rotated about the main bearing axis the grinding wheel follows and is held in contact with the crank pin to grind the same. A deflector plate 45, Fig. 1, prevents metal particles from falling, on the motor 20. The tailstock 4, Fig. 5, including a rolling centre 5 in a hollow casing 66, is so constructed that a single movement of a lever 72, pivoted at 73 with a cam 74, from a low to high position first pivots a lever 75 to move the centre 5 axially against a spring 79 to release the work, then, through a lever 67 and locking member 68 releases the tail stock from its slide, the reverse taking place when the lever 72 is moved from a high to low position. A wheel trueing device 70, Fig. 1, comprises, Figs. 7, 8, a diamond 80 on a carrier 81 adjustable longitudinally by a nut 82 and a notched bush 83 engaging a spring- pressed plunger 84 providing a " click stop " setting arrangement. The carrier 81 is mounted on a slide movable on a slideway 85 by feed screw mechanism 87 so that the diamond is traversed across the grinding wheel. A thin wedge plate 89, mounted between the trueing attachment and the grinding wheel cover and having arcuate slots 90 therein through which pass bolts 91, serves when adjusted to give an accurate initial setting.