When assembling relatively large structures such as automobiles and the like it is common to use skids as a carrying structure for the automobile during its assembly. The skid is transported along rails on the factory floor such that a worker may work on the automobile while the automobile is being transported to or through the particular work station. At the end of the transport system a build-up of skids may occur in situations where the following process steps are slower or falling behind the production cycle of the previous assembly line. Therefore a number of skids will accommodate in this area and the skid buffer system must be able to accumulate skids and keep trans-porting other skids further behind on the line.
For this purpose a skid buffer system is usually provided with members supporting the skids on the conveyor line where the support means incorporate rollers such that when the skid is halted either by a stop or by a another skid in front of it the conveyor belt will be able to maintain its rotation thereby accumulating the skids in a certain position. In the art there are a number of constructions where these conveyor belts comprising roller constructions are illustrated.
An example is illustrated in DE 102004009842 wherein a conveying chain is provided with an adaptor shoe fitted over and onto the chain links where the adaptor shoe comprises a roller such that by arranging the adaptor shoe at intermittent intervals along the conveyor chain a relatively high density of support rollers is provided for the skids which are to be placed on the conveyor belt.
Another installation is marketed by the company Fata Automation.
These systems all provide add-on rollers to either endless rubber belt conveyors or chain conveyors, i.e. conveyors made out of modular belt links.
In EP 1655243, NL 1010530 and WO01/83338 are illustrated conveyor belts where the upper side of the belts are provided with rollers. The rollers are integral with the belt links. A plurality of rollers are arranged laterally relative to the transport direction. These types of belts are used as accumulating belts, i.e. belts used for transporting a number of smaller products, which for one reason or the other will be accumulated on the belt. The rollers allow the belt to keep circulating even though the products are stationary.