Abstract: A turn conveyor system includes a plurality of friction-reducing members disposed along at least the inner edge of the belt to minimize the friction between the belt and the conveyor frame. The members are formed, in whole or in part, from a plastic material having a coefficient of friction of less then 0.2 and may advantageously include raised vee-shaped portions adapted to remove debris from between the belt and the frame.

Abstract: A plastic sprocket wheel includes a sprocket body having a series of circularly spaced recesses located around a body circumferential edge, there also being a body side face opening in at least one body side face which communicates with the recess edge openings so that replaceable tooth elements can be slidably inserted into an associated recess when tooth replacement such as required when one or more teeth of an operating sprocket break or are rendered unusable. The replacement mounting requires no separate fastening devices for holding replacement teeth securely to the sprocket body, friction fit being sufficient to that end. The sprocket body is of resilient material such as an acetal, a polyethylene, a polypropylene etc., and the tooth elements can be of metal or the same material as the sprocket body, or such can be a combination of materials, e.g., a strong metal tooth piece molded in a resilient or plastic material core.

Abstract: An improved conveyor belt and an improved capstan coact to yield a spiral conveyor having a reduced lateral turning radius. Power transmission from the capstan to the conveyor is increased by projections on the inner edge of the belt that cooperate with grooves on the peripheral surface of the capstan. The projections have a cross section in the form of half a teardrop to facilitate disengagement from the rotating capstan. The grooves are longitudinally formed in bars disposed in parallel about the periphery of the capstan. The bars are inclined such that the grooves are generally parallel to the relative motion of the belt inner edge and the capstan peripheral surface. The conveyor belt is further provided with a central tension fibre comprising a plurality of longitudinally disposed interconnecting links, each in the form of an asymmetrical clevis, specially adapted to transmit power from the capstan driven inner edge of the conveyor belt to the dragging outer edge.