Machine for machining crankpins of a multiple-throw crankshaft

Claim 1

A machine for milling crankpins of a multiple-throw crankshaft having two ends and comprised of alternating mainshaft portions and crankpins between the two ends, including three axially consecutive crankpins and two axially consecutive mainshaft portions connecting the three crankpins, which comprises the combination of (a) a machine bed extending in a longitudinal direction, (b) gripping means on the machine bed for gripping the crankshaft at the two ends and positioning the crankshaft with its axis extending in the longitudinal direction, (c) two longitudinal carriages mounted on the machine bed between the gripping means for relative movement to the machine bed in the longitudinal direction, the carriages defining a gap therebetween and the carriages permitting the crankshaft to pass therethrough, (d) a tool carriage mounted on each one of the longitudinal carriages for relative movement thereto in a direction transverse to the longitudinal direction, the tool carriages permitting the crankshaft to pass therethrough, (e) a stay mounted on the machine bed in said gap for relative movement to the machine bed in the longitudinal direction, the stay carrying (1) two supports spaced apart in the longitudinal direction for radially engaging and supporting two axially consecutive mainshaft portions extending through the gap, and (f) an annular milling tool carried by each one of the tool carriages and having radially inwardly directed cutting teeth operable to mill a respective one of the three axially consecutive crankpins extending from a respective one of the supported mainshaft portions towards a respective end of the crankshaft.