Generic road pavers or feeders, hereinafter also collectively referred to as road construction machines, are used for laying base layers, for example, concrete or asphalt layers, for example in road construction (road paver) or for intermediate storing and transferring paving material during the paving process (feeder). The respective base layer is paved by a road paver, which is supplied with construction material for the base layer directly by a transport vehicle, for example, a truck, or via a feeder during the paving process. When using a feeder, it is supplied with paving material by a transport vehicle, and transfers the paving material via a suitable conveyor device to the road paver, which prepares the base layer. Both the paver and the feeder have a machine frame and a travel unit, for example, crawler tracks or wheels, driven by a drive unit, in most cases a diesel engine. In the operating direction of the road construction machine, it has a material hopper in the front. The operating direction refers to that direction in which the road construction machine moves during normal operation, i.e., during paving operation. The material hopper is a loading space for paving material, the size of which can be increased and/or decreased by moving and/or tilting the hopper walls. The material hopper includes a hopper floor and side walls extending in the operation direction and normally also a rear wall. The paving material is conveyed backwards or towards the rear from the material hopper via a conveyor device, for example, a scraper belt, through the road construction machine, where, in the case of a feeder, a conveyor device is arranged, which transfers the paving material from the feeder to the road paver. In the case of a road paver, a transverse conveyor, for example, a screw conveyor, and a paving screed are located on the rear, through which the paving material is spread across the entire paving width, smoothed, and pre-compacted. A smooth, pre-compacted base layer is left behind the road paver, which can be further compacted, for example, by rollers, in order to achieve a finished road.
The transfer of the paving material from the transport vehicle to the generic road construction machine, be it a feeder or a road paver, occurs respectively in the same way. A truck loaded with the paving material drives backwards to just in front of the road construction machine driving in the operating direction and then stops. A controlled collision between both vehicles is then effected. For this, a collision device such as buffer rollers may be present, for example on the end of the road construction machine located in the front in the operating direction, which come into contact with the rear of the transport vehicle by slowly moving the road construction machine forward. The road construction machine then pushes the transport vehicle in front of it using the buffer rollers, while the paving process of the road paver is continued. The transport vehicle can then transfer the paving material, for example, by tilting the loading area backwards into the material hopper of the road construction machine arranged in the front in the operating direction. As soon as the transfer is completed, the loading area can be lowered again and the transport vehicle drives away in the forward direction.
The driver of the transport vehicle needs to approach the hopper edge of the road construction machine located in the front in the operating direction with the rear end of the transport vehicle in a targeted manner. The region of the hopper edge of the road construction machine located in the front in the operating direction, to which the rear end of the transport vehicle needs to be guided to, is also called approach zone. The approach zone is mostly predetermined by the extension of the collision device, for example the buffer rollers, transverse to the operating direction. Typically, the approach zone is arranged in the center of the road paver or feeder and spaced from the side walls of the material hopper, so that these are arranged outside the approach zone. When positioning the transport vehicle in front of the road construction machine, which is not exactly centered or which is located outside the approach zone, respectively, it happens that the rear end of the transport vehicle comes into contact or collides with one of the foldable side walls of the material hopper located outside transversely to the operating direction. The side wall of the hopper can bend due to heavy and/or constant collisions. In the long run, this can lead to a loss of functioning of the foldable side walls of the material hopper of the road construction machine in the worst case. Due to the plurality of loading processes, which are necessary in the working mode of the road construction machine, such damages to the road pavers of feeders known from the prior art can often not be prevented in the long run, even with careful drivers of the transport vehicles.
DE 10 2013 216 374 A1 discloses a road paver, which provides folding elements on the hopper adjustable toward the loading vehicle. These folding elements can be adjusted from a projecting position in the direction of the interior of the mixing material container. The folding elements of DE 10 2013 216 374 A1 serve for preventing the mixing material from falling out of the mixing material container in the paving process. It is provided that the folding elements are swung open toward the front when filling the hopper, in order to enlarge the front opening of the hopper during the loading process.