Patent Application
20150233081
The invention relates to a cover of a structure that can be installed in the ground according to the preamble of Claim 1.
Channels and shafts that are covered by covers are known structures for installation in the ground or (in particular) for the drainage of surfaces. These covers are partially driven over by motor vehicles; in particular, however, these are walked over by pedestrians. There is a risk of slipping and thus a risk of injury, in particular when it is wet or contamination has accumulated.
Covers, in particular covering grates, are known in a plurality of embodiments. Thus, for example, DE 1 853 985 U, DE 20 2006 014 082 U1, DE 89 09 748 U1 or DE 1 876 986 U disclose covering grates that have been provided with a surface structure in the form of (wedge-shaped) slots or elevations having a triangular cross-section. In addition, drainage covers according to the preamble of Claim 1 are known, for example from the German design patent M 9 505 847, which have elevations that are supposed to ensure slip resistance.
The known configurations provide only limited anti-slip effect however. In particular when the covers are manufactured out of a plastic material, in particular injection molding, contamination occurs easily, which contributes to an increased risk of accident.
In addition, the known anti-slip structures provide sufficient anti-slip in interior areas, e.g. swimming pools, in which clean water without contamination particles wash over the covering grate. As soon as contamination particles reach the outer area of the covering grate however, the known macro-structures (e.g. these known corrugations) and micro-structures (grain) become clogged up due to the entry of a mixture of contamination particles and water, and a sufficient anti-slip effect is no longer possible.
The object of the invention is to provide a cover of the type mentioned above, such that an increased slip resistance is ensured at the lowest possible expense.
This object is achieved by a cover according to Claim 1.
This object is achieved, in particular by a cover of a structure that can be installed in the ground, in particular a shaft, a point runoff, a drainage channel or similar drainage installation, comprising a surface that can be walked over or driven over, having a planar structure in a first, lower plane, and having elevations with top surfaces of the elevations, which lie in a second, higher plane of the planar structure, in that the top surfaces of the elevations have an anti-slip surface structure, which comprise a plurality of individual elevations, wherein the ratio of the air volume below the individual elevations to the volume of the individual elevations Vv/Vm, is preferably (0.01 to 0.5)/(0.001 to 0.05), preferably (0.02 to 0.2)/(0.002 to 0.01).
The anti-sip structures are thus displaced vertically and upward from the actual covering later (the lower plane) so that significantly more contamination particles are needed to fill the space between the anti-slip structures and neutralize the anti-slip effect.
Thus an essential aspect of the invention is that, even when contamination particles are introduced into the anti-slip surface structure, these can be easily washed away or displaced into the regions between the elevations as a result of people walking on the surface.
The individual elevations preferably have different maximum heights. This ensures that even in the case that contamination particles accumulate in the different height ranges of the anti-slip structures, these contamination particles themselves have different heights, and in this way, themselves exhibit an anti-slip effect.
It is possible that the lower situated planar structure in the first, lower plane has an anti-slip surface structure, which is not as rough as the anti-slip surface structure of the top surfaces of the elevations. The lower-lying planar structure may have a grain, for example, in order to achieve a specific visual effect, for example a casting effect, as well as in order to increase the roughness, and therefore may have the anti-slip characteristics of this planar structure.
The maximum heights are preferably provided within a distribution within a range of Sz=150 μm to 1,500 μm, preferably between 230 μm to 1,000 μm. This rated value (like the rated value in the subsequent description as well as in the claims) has been obtained from DIN EN ISO 25178. Explicit reference is made to this standard, wherein the measurement methods that result in the values described below are likewise described therein.
The distribution of the individual elevations or, respectively, the size thereof may be uniform. Preferably, however, a distribution will be selected in a random distribution across the surface so that higher and lower individual elevations are also provided within smaller areas.
The individual elevations may be provided in different shapes (when viewed as a horizontal section). The individual elevations are preferably designed having a pyramidal shape or truncated pyramidal shape, however.
The maximum depression height of the individual elevations (they are also referred to as recess heights) is Sv=50 μm to 500 μm, preferably 85 μm to 310 μm. Surprisingly, this range has proven to be especially beneficial.
The roughness value of the surface structure is preferably Sa=10 μm to 200 μm, preferably 15 μm to 90 μm. The elongated appearance ratio (pursuant to DIN EN ISO 25178, also referred to as a developed transition surface ratio) of the surface structure is preferably Sdr=20 to 300%. The surface structure preferably has an apex density of Spd=0.5 to 20 mm−1, preferably 1 to 10 mm−1.
Surprisingly, the above-mentioned size ranges have an effect such that on the one hand, injuries on these apexes rarely occur, and on the other hand, sufficient slip resistance and “self-cleaning effect” is achieved.
The invention is described in greater detail below on the basis of the Figures. Shown are:
As can be seen in the Figures, the embodiment of the grate 10 shown here has a support structure, which has a surface 11 that lies in a first, lower plane. The surface 11 is interrupted by drainage openings 12 and forms a smooth, planar structure 13. Here, the planar structure 13 is equipped with very little surface roughness, for example, such as that achieved on a surface that is created by means of plastic injection molding.
Rod-shaped elevations 14 are provided on this surface 11, the top surfaces of the elevations 15 of which have the roughness described above, which is obtained by corresponding shaping of the injection mold, in particular in the case of injection molding. Here, the top surfaces of the elevations 15 comprise individual elevations 16, which, as indicated in
This shaping ensures that on the one hand, contamination particles that reach the elevations 14 can be easily rinsed away, and conveyed on the smooth, planar surface 13. The contamination particles, on the other hand, are carried away from the smooth planar structure 13 into the drainage openings 12, so that a kind of “self-cleaning effect” is created by the design selected here. Even when walking thereon, the accumulation of contamination particles as is reduced through the forces exerted, since these contamination particles are squeezed out over the top surfaces of the elevations 15 and conveyed on the planar structure 13 so that these may ultimately enter the drainage openings 12.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2012 108 392.4 | Sep 2012 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2013/068537 | 9/9/2013 | WO | 00 |
