Machine tool leverage control handle

Abstract

A reversible torque hand crank or lever for machine tools comprises a generally elongated cylindrically outlined hub having a blind bore located axially in the mounting face of the hub for mounting the hub fixedly to a feed mechanism shaft of the machine. The end of the hub opposite the mounting face has a generally flat lever mounting face substantially parallel to the hub mounting face. An arm guide channel having parallel arm support side walls and oppositely disposed symmetrical straight bottom walls which walls are sloped from the apex to form guide arm support planes depending outwardly at an obtuse angle to the hub faces is located diametrically and transversely on said hub. A pair of oppositely disposed hub bearing bores are transversely located in said hub perpendicular to said channel at its apex. An elongated crank lever arm having a bearing in one end is pivotably and slidably mounted in said hub channel by a moderately sized pin inserted through the hub bearing and lever bearing bore allowing the lever to pivot from side to side in the channel with a substantial portion of the lever extending outside of the channel and biased outwardly for leverage. The channel arrangement provides quick reversal of the arm from one side to the other and to the arm under conditions of extreme load in turning the hub. Detent means is provided in the hub to hold the crank arm releasably in either position.

Dependencies are inferred from the claim text.