For the transport of articles, packs and packaging goods horizontal conveyors are used in numerous variants. A common variant of such a horizontal conveyor comprises so-called link conveyor belts or conveyor chains, whereby the conveyors provide conveying sections with support planes for the delivery of the goods. Several of these conveying sections can border on each other, whereby the link conveyor belts or conveyor chains are formed from a plurality of interconnected articulated chain links or belt links. To use the link conveyor belts or conveyor chains as endlessly circulating traction means, they can be deflected at least in the vertical direction. For a universal application of these bands or chains several aspects are important, e.g. their sufficient mobility, the properties that allow a deflection around horizontally rotating deflection rollers or deflection wheels with a rather small deflection radius. On the other hand, the chains must allow some reverse bending, whereby the conveyor chain is bent concavely in relation to its conveying surface. This is necessary since, depending on the given installation conditions, some multiple diversions might require such reverse bending. Not least, the link conveyor belts or conveyor chains should have a very flat and uniform support plane for transporting products with small base areas without the products tipping over.
For many applications, an anti-slip or smooth surface of the link conveyor belt is hindering, for example if the transported articles need to be backed up. To allow an easy sliding of the articles, the link conveyor belts or conveyor chains can have running rollers or supporting rollers on their conveying plane, on which the articles, containers and packaging materials can easily move in or opposite to the conveying direction. For this purpose, these rollers each have horizontal axes of rotation, which are arranged transversely to the conveying direction. Normally, the rollers are in an elevated level in relation to the supporting hinge parts and chain links, so that the rollers form a substantially uniform support plane.
Such a link conveyor belt is described, for example, in document DE 35 41 364 A1. The link conveyor belt disclosed therein comprises a plurality of pivotally interconnected support links, which each have bearing blocks on their upper sides for receiving axles, whereby rollers are mounted on these axles.
In order to prevent a formation of too large gaps between successive conveying sections of successively arranged link conveyor belts, smallest possible radii of deflection during the guided tours of the conveyor chains are desirable, as gaps might lead to significant conveying problems and tip over problems for some transported articles. Link conveyor belts according to the embodiment described in DE 35 41 364 A1 have rollers, which are arranged above the support links. In narrow deflection radii distinct gaps are formed between the rollers of adjacent support links. In practice this creates a non-acceptable risk during manual intervention in the conveying section of the link conveyor belt. Because of small deflection radii relatively large gaps are formed between the adjacent rows of chain links. When these gaps close during the transition to the horizontal conveying section, this constitutes a risk of injury by crushing. Therefore additional security measures against manual intervention are indispensable.
EP 1 752 395 B1, hereby incorporated by reference herein, discloses a conveyor chain with hingedly interconnected chain links, whereby the chain links each support double rows of running rollers. Additional supporting sections are arranged between the rows of running rollers of each chain link, which largely close the gaps between the adjacent roller rows. However, such supporting sections are absent between adjacent roller rows of adjacent chain links. Therefore there is no protection against manual intervention when a gap opens up because the conveyor chain is guided over a deflection roll.