Device for planetary electrode wire-feeding having automatic adjusting means for the pushing force exerted on the electrode wire

摘要

A planetary electrode-wire feeding device in which the calibrated pushing force exerted on the electrode wire by a pair of feed rollers is automatically adjusted. This automatic adjustment is effected by a cam which is drivingly connected to a drive motor. A housing is operatively drivingly connected to the cam for rotation via a pair of double-armed levers. The housing has a pair of radial bores in which a pair of pistons are respectively reciprocally mounted. Upon a predetermined rotation of the cam, one arm of the double-armed levers is pivoted outwardly and the other inwardly, thereby the pistons are pushed inwardly by the double-armed levers and, due to a wedging action between the levers and the housing, the latter begins to rotate and the electrode wire is pushed forwardly by feed rollers.