Patent ID: 6202461
Filing Date: 2001-03-20
Classification: B21H

Abstract:
In a thread rolling attachment for a machine of the type having a slide reciprocable transversely of a rotating workpiece for selectively engaging a pair of threading rolls on the attachment into tangential rolling engagement with the workpiece, the improvement comprisinga generally yoke-shaped bracket secured on said slide for reciprocation thereby to and from said workpiece, said bracket having a closed end and a pair of spaced, parallel arms integral with and projecting outwardly from said closed end toward saidworkpiece,a pair of spaced fulcrum pins extending transversely between said bracket arms and generally parallel to the axis of rotation of the workpiece,a pair of roll arms pivotally mounted intermediate their ends on said pins, each of said roll arms having an inner end facing and spaced from said closed end of the bracket, and an outer end extending beyond the outer ends of said bracket arms,a pair of spaced thread roll rotatably mounted on the outer ends of said roll arms, and a pair of spaced roller followers rotatably mounted on the inner ends of said roll arms,a thread roll adjusting element adjustably mounted between the arms of said bracket adjacent the closed end thereof and having a generally wedge-shaped forward end extending between said roller followers,resilient means urging each of said roll arms in a direction to maintain said roller followers in rolling engagement with opposed, inclined surfaces formed on said wedge-shaped end of said element, andmeans for adjusting said element including a knob rotatably mounted on said closed end of said bracket and operatively connected to said element, said knob being rotatable manually to shift said element selectively in opposite directions thereby to vary the space separating said followers and consequently the space separating said thread rolls,said adjusting means including a screw secured at one end to said knob for rotation thereby about an axis extending normal to the axes of said fulcrum pins, and having on its opposite end an externally threaded shank portion extending into an opening in said element, andmeans in said opening supporting said element on said screw for movement axially of said shank portion thereof and for limited pivotal movement relative thereto about an axis normal to the axis of rotation of said screw.