Powder rolling apparatus

Claim 1

In apparatus for compacting metal powders comprising a pair of generally cylindrical rolls of equal length mounted for rotation about respective parallel spaced roll axes to define a roll gap therebetween, means for feeding metal powder to an intake side of the roll gap along the entire length of the roll faces to be compacted to a strip-like product of width substantially equal to the roll face length and edge-restraint means at opposite axial extremities of the rolls effective to prevent powder egress from the roll gap in a direction parallel to the roll axes, the improvement wherein each edge restraint means comprises a wheel mounted to lie parallel to a plane containing the rolling direction and to be freely rotatable about an axis perpendicular to the roll axes, a pneumatic tire of width exceeding the roll gap mounted on the rim of the wheel, and means for urging the wheel towards the respective end-face of each roll so as to cause a portion of the surface of the pneumatic tire into frictional contact with a portion of the end-face of each roll, whereby in operation the wheel is frictionally driven by the rotating rolls and a deformed portion of the tire surface provides a mating powder seal with the roll end-faces at, and in the vicinity of, the roll gap.