Accumulating roll conveyor

Claim 1

In an accumulating type roller conveyor in which a supporting frame includes a pair of spaced apart parallel longitudinally extending side frame members, a plurality of parallel conveyor rollers extending transversely between and journaled on the side frame members, a drive shaft for each of the rollers rigidly secured thereto for driving the same and each shaft having an end portion projecting co-axially from one end of its associated roller and outwardly beyond a common one of said side frame members and being of hexagonal external configuration, and a chain sprocket wheel journaled on said end portion of each shaft for rotation relative thereto; the invention characterized in that each chain sprocket wheel is provided with a hub having an internal surface spaced radially outwardly from the shaft end portion providing a generally annular space therebetween; a sleeve freely axially slidably but non-rotatably mounted on the shaft end portion and having an external circumferential surface opposed to said internal surface of the hub but spaced radially therefrom to define an annular space therebetween, one of said surfaces having one or more radially displaced portions projecting toward the opposed surface to provide one or more narrowed spaces between the opposed surfaces; at least one resiliently compressible torque transmitting rollable element disposed in said annular space and serving to drivingly couple each sprocket wheel to its associated drive shaft and roller, each said torque transmitting element normally acting to transmit the rotation of its sprocket wheel to the end portion of the drive shaft through said sleeve with which it is associated as long as the resistant load applied to the associated roller and shaft does not exceed a predetermined limit, but when such load does exceed this limit the torque transmitting element is rollably squeezed past said one or more narrowed spaces thus automatically discontinuing the driving relationship between the sprocket wheel and the shaft until the resistant load imposed on such shaft falls below said limit whereupon the drive shaft is again drivingly coupled to the sprocket wheel; the invention being further characterized in that a pair of sealed anti-friction bearings is received within opposite ends of each sprocket hub for journaling the same on the shaft end portion and defining axially opposite ends of the annular space in which the one or more torque transmitting elements are contained, each such anti-friction bearing having an inner race slidably received on the shaft end portion, annular sealing means between the inner race of each anti-friction bearing and the associated shaft end portion to prevent migration of contaminating media along the shaft into said annular space; and means for removably locking the bearing nearer the outer end of the shaft within the hub but permitting removal of the bearing to gain access to the one or more torque transmitting elements and said sleeve in the hub for replacing such elements and/or sleeve by similar elements of different resilient compression or sleeve of different external diameter or configuration and accomplishing such operation without disturbing the conveyor rollers and any articles supported thereon.