Lock nut forming apparatus

Abstract

A heavy duty press mechanism, whose ram is driven by means of an eccentric crank and pitman, carries a head with four aligned indention punches for distorting thread pitch simultaneously on four axially aligned hex nuts. A feed track system feeds a row of axially aligned hex nuts under the punch head. A reciprocating ejector-stop, synchronized with the punch ram, simultaneously ejects a group of four indented nuts and defines a stop for the following group of nuts at the indention station. A feed system includes an axial feed track for feeding nuts to the indention station, a lateral feed track, and a transfer speed coupler coupling these tracks. A vibrating hopper feeds laterally aligned nuts into the lateral feed track, where a single row of side-by-side nuts is fed by gravity to the speed coupler. The speed coupler effects a transfer from lateral feed to axial feed into the axial feed track. Air jet means initiates the axial feed of nuts in the speed coupler; and a vibrator associated with the speed coupler contributes to the smooth, fast transfer of nuts from lateral feed to axial feed. The indention punches deform the material of one wall of each nut, producing accurately controlled thread deflection into the threaded bores, and also produce a controlled, slight ovaloid shape of the hex nut.