DE8911160U1 - Multilayer concrete roof tile - Google Patents

Description

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Description Multilayer concrete roof tile

The innovation relates to a concrete roof tile that can be produced using the extrusion process and has at least one lower layer and one upper layer. Such a two-layer concrete roof tile is known, for example, from OE-BB IS 15 §73. The document in question describes a process in which a top layer is applied to a lower layer of concrete produced using the extrusion process by means of a second extrusion process. The disadvantage of this process is that the surface of the base layer is whirled up using a spray gun, so that the production of a concrete roof tile with a thin top layer is not possible.

The aim of this innovation is to create a concrete roof tile that has a wear-resistant, frost-resistant, pore-free, smooth, visible surface and whose production is economical at a cycle speed of more than 100 pieces per minute.

According to the innovation, this object is achieved in that the top layer consists of concrete containing fine-grained sand and optionally additives such as color pigments and covers at least the top side visible when the concrete roof tile is covered, that the top layer has a uniform layer thickness of less than 4 mm, preferably less than 2 mm, in relation to the average roughness depth of the bottom layer, wherein the layer thickness varies by less than +/- 0.3 mm, and that the front surface of the concrete roof tile which is lower when the concrete roof tile is covered has an edge which is rounded towards the top side, wherein the top layer covers at least 50% of the height of the front surface.

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If fine-grained sand is used for the concrete of the top layer , a smooth surface is achieved by the extrusion process. The uniformity of the layer thickness makes it possible to make the layer so thin that the additional costs are minimal. This makes it possible to reduce the thickness of the intermediate layer to less than 1 mm. Since the material used is native to the type of material, i.e. concrete, the top layer is firmly bonded to the bottom layer and the top layer has essentially the same mechanical and thermodynamic properties as the bottom layer.

Advantageously, the top layer has an extremely uniform layer thickness, which varies by less than +/- 0.1 mm.

The concrete roof tile has a particularly smooth and pore-tight surface if 95% of the sand grains contained in the top layer have a grain size of less than 0.6 mm and 70% of the sand grains have a grain size of less than 0.3 mm.

The frost resistance of the concrete roof tile is increased if the top layer completely covers the front surface. This prevents freezing water from entering the depressions on the front surface.

Further details, advantages and features of the innovation emerge from the following description of preferred embodiments shown in the drawing.

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Show it:

Fig. 1 a concrete roof tile according to the innovation

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Fig. 2 the concrete roof tile from Fig. 1 in cross section,

Fig. 3 a second embodiment of a

Concrete roof tile according to the renovation in longitudinal section, 1.0

Fig. 4 shows the concrete roof tile from Fig. 3 in cross section.

Figures 1 and 2 show a new concrete roof tile

(10) shown in longitudinal section or cross section, which has a commercially available profile with a cover fold (12), a central rim (14), a water fold (16) and two watercourses (18, 20) arranged between them. On a sub-layer (22) made of concrete with sand grains of up to 4 mm in size, which is 11 mm thick in the area of the watercourses (18, 20), there is a top layer (24) made of fine-grained sand and concrete containing color pigments with an average layer thickness of 1 mm +/- 0.1 mm based on the average roughness depth of the sub-layer. On the front surface (26) of the concrete roof tile (10), which is arranged lower when the concrete roof tile (10) is covered, the top layer (24) covers more than 50% of the height of the front surface (26). The upper edge (28) of the front surface (26) is rounded. In the area of the water fold (16) which is not visible when the concrete roof tile (10) is covered, the base layer (24) is continuous over the entire thickness of the concrete roof tile (10).

Figures 3 and 4 show a second embodiment of a concrete roof tile (50) according to the innovation in longitudinal section and cross section respectively. In its outer contours and materials, the second concrete roof tile (50) corresponds

the first concrete roof tile (10) described above, but the upper layer (74) covers the entire lower layer (12), thus also the area of the water fold (66) and the front surface (76) arranged lower in the covered state of the concrete roof tile (50) over its entire height.

Claims (4)

Protection claims Multilayer concrete roof tiles 1. Concrete roof tile which can be produced by extrusion and has at least one lower layer and one upper layer, characterized in that the upper layer (24, 74) consists of fine-grained sand and possibly concrete containing additives such as color pigments and covers at least the upper side visible in the covered state of the concrete roof tile (10, 50), that the upper layer (24, 74) relative to the average roughness depth of the lower layer (22, 72) has a uniform layer thickness of less than 4 mm, preferably of about 1 mm, wherein the layer thickness varies by less than +/- 0.3 mm, and that the lower end face (26, 76) of the concrete roof tile (10, 50) in the covered state of the concrete roof tile (10, 50) has an edge (28, 78) rounded towards the upper side, wherein the upper layer (24, 74) covers at least 50% of the height of the end face (26, 76). 2. Concrete roof tile according to claim 1, characterized in that the layer thickness of the upper layer (24, 74) varies by less than +/- 0.1 mm. 3. Concrete roof tile according to claim 1 or 2, characterized in that 95% of the sand grains contained in the upper layer (24, 74) have a grain size of less than 0.6 mm and 70% of the sand grains have a grain size of less than 0.3 mm. 4. Concrete roof tile according to one of the preceding claims, characterized in that the upper layer (74) completely covers the front surface (76).