Conveyor belt system

#The present invention describes a conveyor system used to transport objects.

#A wide variety of powered conveyor systems have been developed for transporting objects. Referring to FIG. 1, prior art conveyor systems typically include a conveyor belt 101, pulleys 103 and a drive mechanism 105. The conveyor belt 101 is mounted tautly around pulleys 103 and a drive mechanism 105 rotates at least one of the pulleys 103 causing the conveyor belt 101 to rotate around the pulleys 103. Objects 107 placed on the moving conveyor belt 101 are transported to the other end of the belt 101 and removed from the conveyor system.

#In some applications it is desirable to have a system which allows a group of objects to be placed on one end of the conveyor belt system before the group of objects is transported. U.S. Pat. No. 4,878,578 describes a conveyor belt system having a moving conveyor belt positioned between two stationary surfaces. The relative elevation of the conveyor belt and the stationary surfaces is controllable. When the conveyor belt is lower than the stationary surfaces, objects may accumulate upon the stationary surfaces and when the moving conveyor belt is elevated the objects are lifted and transported by the conveyor belt. The elevation of the conveyor belt is controlled by the operator with a complex “split cam” mechanism having special cams, rods and magnets. The belt slides rather than rolls over non-rotating cams which causes drag friction between the belt and cam.

#The invention is herein described, by way of example only, with reference to embodiments of the present invention illustrated in the accompanying drawings, wherein:

#FIG. 1 is a simple conveyor system (prior art);

#FIG. 2 is a side view of a conveyor belt system with eccentric pulleys;

#The present invention addresses the above and other problems associated with variable elevation conveyor belt systems. The present invention is a simple conveyor system which allows objects to accumulate on stationary surfaces at one end of the conveyor system prior to transporting the group objects with the conveyor belt.

#Referring to FIG. 2, an embodiment of the inventive conveyor system 200 is illustrated. For simplicity only a single conveyor belt 205 mounted on two pulleys 207 are illustrated. The inventive system typically has several conveyor belts 205 rotating in parallel each mounted on a set of pulleys 207. The inventive conveyor system 200 includes stationary surfaces 203 having a common plane mounted on either side of the conveyor belt 205. The conveyor belt 205 rotate about two pulleys 207 which have an eccentric axis of rotation 221 with a maximum radius 223 and a minimum radius 225. The pulleys 207 rotate synchronously so that portions of the upper surface of the conveyor belt 205 defines a plane substantially parallel to the stationary surfaces 203. The pulleys 207 are configured so that the upper surfaces of the conveyor belts 205 cyclically moves between positions above and below the plane of the stationary surfaces 203. Thus, when the upper surface of the conveyor belt 205 is below the stationary surfaces 203, items 209 placed on the conveyor system 200 can rest on the stationary surfaces 203. All items 209 to be transported are placed on the stationary surfaces 203 before the conveyor belt 205 rises above the stationary surfaces 203.

#Referring to FIG. 3, as pulleys 207 rotate the maximum radius 223 rises above the axis of rotation 221 and the upper surface of the conveyor belt 205 rises above the plane of the stationary surfaces 203. The items 209 are lifted off of the stationary surfaces 203 and transported by the moving conveyor belt 205 to the other end of the conveyor system before the upper plane of the conveyor belt 205 falls below the plane of the stationary surfaces 203. When the items 209 are moved to the opposite end of the conveyor system they are removed from the conveyor belt 205.