Belt conveyor

In a belt conveyor having at least one straight load bearing zone and comprising:

• a. a pair of flexible elementary belts each having a neutral axis and a reinforcing layer embedded in the vicinity of said neutral axis so as to reinforce each belt at least longitudinally;
• b. a regular array of projections and intermediate recesses arranged on one side of each elementary belt so that the projections of one belt fit exactly into corresponding recesses of the other belt thereby to provide positive engagement with rigid interlocking of the elementary belts so as to render them solid with each other, at least longitudinally by their superposition and positive engagement along straight portions thereof;
• and
• c. belt guide means which define the paths of the elementary belts so as to provide:
• first curved path portions arranged to bring the elementary belts progressively together into mutual positive engagement and rigidly interlock relationship at one end of said load bearing zone of the conveyor;
• a common straight path portion wherein the superposed elementary belts remain positively engaged and rigidly interlocked from said one end to the opposite end of the straight load bearing zone and are thereby made solid with each other at least longitudinally whereby to transmit shear forces due to flexure from one belt to the other, so that the elementary belts thereby form together a straight, rigid composite beam assembly wherein the respective reinforcing layers of the belts of this assembly exert a combined reinforcing action providing substantial rigidification of the composite beam assembly;
• and second curved path portions arranged to progressively disengage and thereby separate said elementary belts beyond said opposite end of the load bearing zone, whereby said belts may separately undergo a desired directional change along their respective second curved path portions, the improvement consisting of:
• d. said guide means including belt deflecting means so arranged in the vicinity of each end of said straight load bearing zone that said elementary belts are deflected in opposite directions around centers of curvature which are longitudinally shifted with respect to each other at each end of said straight load bearing zone, to thereby substantially obviate friction between said projections and recesses when said belts are on the one hand progressively engaged and thereby brought into rigidly interlocked relationship at one end of said straight load bearing zone, and when the rigidly interlocked belts are, on the other hand, progressively separated from each other beyond the opposite end of said straight zone of the conveyor.