Geared belt for positive drive transmission

Claim 1

A geared belt for the positive transmission of motion between the belt and a toothed sprocket, said belt comprising, thick, solid and substantially rigid gear teeth projecting from one side of the belt in repeating spaced apart relationship having lateral tooth faces to be contacted by sprocket teeth, successive thin flexible portions bridging the spaces between successive gear teeth and connected thereto with longitudinally extending surfaces of the flexible portions on the gear teeth side of the belt defining a dedendum line of the belt gear teeth, said teeth being substantially stiffer than the thin flexible portions therebetween, said belt forming a continuous non-articulated band that is subjected to tension stress when in engagement with the sprocket and when transmitting motion to or from the sprocket, said belt being subjected to bending stresses that are induced by contact between the belt gear teeth and the sprocket teeth when entering or leaving meshing engagement, said belt being crimped to curve transversely at the junctures between the stiff teeth and the thin flexible portions therebetween with said dedendum line longitudinal surfaces on said one side of the belt merging toward and into said tooth faces in a concave fillet, and the surfaces of said flexible portions on the other side of said belt convexly curving toward said teeth thereby to define indented portions of said belt at said teeth and to offset the other side of said belt and said teeth laterally from the flexible portions so that belt tension induces within the crimped portions of the belt flexural stresses that counteract bending stresses induced therein by contact between the belt gear teeth and the sprocket teeth when entering or leaving meshing engagement.