Abstract: A power drive system including a toothed belt (10) arranged for improved engagement with a grooved pulley (15). The belt teeth (13) define, in longitudinal cross section, planar flank surfaces (22, 23) and an intermediate arcuate tip surface (25). The pulley groove (14) has corresponding planar flank surfaces (17, 18). The arcuate distal portion of the belt tooth is disposed within an arcuate segment centered on the point of intersection (19) of a flank surface (17) of the belt pitch line (20) defined by the tensile members (12) of the belt body portion. The tooth tip portion (25) defines a circular cross section centered on a point (37) disposed within a preselected range on the tooth centerline (24).

Abstract: A belt tooth is provided with an arcuate surface at its tip for engaging and compressing against the bottom surface of a pulley groove to decrease noise and vibration in a toothed belt power transmission system.

Abstract: A rubber screen for a vibratory screening apparatus comprises a plurality of first parallel rope members having suitable cross sectional shapes and arranged in a particle flowing direction, each of said first rope members having a tensile member composed of a strand of filament having a high elongation at break and an organic material having flexibility and/or elasticity and covering the tensile member, and a plurality of second parallel rope members having suitable cross sectional shapes and arranged in a direction normal to the first rope members, each of the second rope members having a tensile member of a material having a low elongation at break and an organic material having flexibility and/or elasticity and covering the tensile member, each point of intersection between the first and second rope members being suitably bonded.