Heat-treating apparatus with roller-type hearth

Claim 1

A heat-treating apparatus having opposed walls defining a work chamber, and a series of side-by-side rollers for supporting workpieces spanning said chamber and adapted to be power rotated to convey the workpieces through the chamber, the improvement in said apparatus comprising, means in said walls mounting said rollers for rotation and for endwise sliding within said chamber, elongated shafts disposed at opposite ends of each roller and journaled for rotation adjacent said walls, at least one of said shafts for each roller being power-rotated and at least one of said shafts being mounted for endwise sliding, means yieldably biasing said slidable shafts toward said rollers, a cup carried on the inboard end of each shaft and telescoped slidably over the outboard end of the adjacent roller with a loose fit, a connection between the telescoped end portions of each cup and roller for coupling the cups and the rollers together for rotation in unison while permitting pivoting of the rollers within the cups, each of said connections comprising a pin anchored to and extending radially through said cup and fitted loosely within an elongated slot formed in and extending axially of the outer end portion of said roller so as to leave the roller free for pivoting within the cup, each of said slots having an axially facing closed end pressingly engaging the associated pin by virtue of the bias applied to said slidable shaft and having an opposite open end opening out of the outboard end of the roller, and the distance between the closed end oF each slot and the outboard end of the associated roller being less than the distance between each pin and the closed end of the adjacent cup thereby to prevent the outboard ends of the rollers from engaging the closed ends of the cups.