DE29816148U1 - Brick - Google Patents

Description

PATENT ATTORNEY DR. HANS GÜNTHER EGGERT

RADERSCHEIDTSTRASSE I, 50935 COLOGNE

4 September 1998 112/98

Tubag Trass, Cement and Stone Works GmbH D-56638 Kruft

brick

Description

The invention relates to a brick, in particular made of clay or loam, which has hollows that extend in the direction of height. Such bricks are known to be produced as follows:

a) Production of a mixture of materials, in particular clay and/or loam with the addition of additives such as sawdust,

b) Pressing the material mixture through a strand die that conforms to the profile of the

brick,

c) cutting individual bricks to length as part of the material pressed through the extrusion die, whereby a brick blank with the desired brick height is produced, and

d) Drying the brick blank.

The individual building blocks are often designed with tongue and groove, so that alignment is easier and stability is higher. The tongue and groove supported arrangement is always carried out in such a way that the tongues and grooves are in the butt joint.

Building blocks that are usually provided with hollow spaces to save weight and material are used. These so-called multi-chamber blocks sometimes have a large number of air chambers (e.g. 2, 4 or 9 chambers), which not only make the block lighter and save material, but also increase the thermal insulation. The dimensions of the air chambers are determined according to DIN 18148, 18151 and 18153.
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To produce bricks, the basic material is first prepared. After the clay or loam has been extracted in the open-cast mine, it is transported to a swamp house for temporary storage. There, different types of clay are mixed. The storage ensures even moisture penetration and homogenization. The mechanical processing of the clay, in particular

r &Lgr; ' »

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The crushing takes place in a pan mill. The basic materials are then mixed in the desired ratio and moistened.

When producing highly heat-insulating bricks, additional porosity is required. This is achieved by adding sawdust. The resulting fine porosity, which fully preserves the natural capillarity of the fired material, results in a favorable drying ratio for the new building, i.e. a rapid reduction in building moisture, as well as good moisture regulation during later use.

The stone blanks are shaped by extrusion. The material is pressed through a nozzle mouthpiece. Individual raw stones are then cut off by a cutter. The material thus shaped goes into the dryer, which can be operated using the waste heat from a tunnel kiln. The drying time varies depending on the format and density and is usually 24 hours. The dried blanks are then fired in a tunnel kiln at around 1,000 ⁰ C for 30 to 45 hours. The residue-free combustion of the porosity substances mentioned causes the fine porosity.

Standardized bricks (DIN 105) can be produced using this process. To create a masonry using such bricks, a layer of mortar is applied between the rows of bricks. A layer of mortar can be up to 12 millimeters thick, which can compensate for dimensional tolerances in the brick.

In addition, so-called flat bricks are also known, which can also be produced using the above-mentioned process. Flat bricks allow the construction of a masonry in which only a thin layer of mortar of approx. 1 millimeter is applied between the rows of bricks. This requires a very high dimensional tolerance of the bricks, so that the process described is necessarily followed by post-processing in the form of a grinding process. This means that the bricks are ground to the required tolerance with high precision.

Despite the high manufacturing costs of flat bricks, such bricks have become popular because masonry can be created quite precisely and easily.

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The disadvantage of this method is that grinding is an expensive production step that is not only capital-intensive (investment in appropriate grinding equipment is required), but also increases the time it takes to produce the stone - and therefore the costs. Another disadvantage is that the grinding dust is an environmental hazard and often cannot be removed from the stone surface, meaning that the mortar bond is poor.

The invention is therefore based on the object of creating a brick that can be used as a flat brick and which, in comparison to a known flat brick, is characterized by the fact that it has improved heat and sound insulation properties.

The solution to this problem is a brick with cavities (6) that extend in the direction of the height (H). According to the invention, it is characterized by

- a brick height (H) adapted to the required wall size,

- whereby the brick (1) is installed without further processing, in particular without grinding, and

- wherein the openings (7) of the cavity (6) on the surface (O) of the brick (I) have cutting burrs (8).

To produce it, the individual bricks (1) are cut to length while maintaining a small tolerance (T) in such a way that further processing of the brick (1) to achieve a defined brick height (H), in particular by grinding, is not necessary.

It is therefore planned that the subsequent grinding of the bricks will be dispensed with entirely, but that the brick's suitability for producing precisely manufactured flat bricks will be achieved by cutting to length with high precision, so that the required tolerance is achieved even without regrinding. The aim is to achieve a tolerance in the brick dimensions, particularly in the height of the brick, of approx. ± 1.5 millimeters.

Although this accuracy is lower than that of the well-known flat bricks, it is sufficient to lay the bricks with a mortar layer of approx. 2 millimeters.

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To cut individual bricks (1) to length, a cutting device (4) can be used, which has a cutting wire (5) that is moved at the nozzle exit speed (v) during the cutting process. It is also advantageous that the cutting device (4) guides the cutting wire (5) using means known per se in such a way that the position accuracy of the cutting wire (5) is less than 0.5 millimeters, preferably less than 0.2 millimeters.

For a stable production process, it is also advantageous that a uniform flow cross-section of the material mixture (2) is maintained over the entire cross-sectional area of the strand nozzle (3).

The cutting burrs can be created using the cutting wire, as material is drawn into the area of the cavity by the wire when the still viscous mass is cut to length. In itself, this is considered rather disruptive in the current state of technology; when the stone is subsequently ground in the case of known flat bricks, the burrs are therefore deliberately removed.

However, the invention is based on the knowledge that the ridge can be used by helping to close the cavities with mortar as completely as possible when applying mortar, so that no hollow chambers are formed that extend over the entire height of the wall, which could trigger a disadvantageous chimney effect and thus negatively affect the thermal insulation properties of the wall. Furthermore, the sound insulation effect of the wall is no longer impaired. The cutting ridges therefore reduce the effective proportion of holes on the surface of the stone.

Preferably, it is further provided that the stone has a brick height (H) of 123 millimeters, 248 millimeters or 498 millimeters with a tolerance of at most ± 2.5 millimeters, preferably ± 1.5 millimeters, for the purpose of precise positioning with a lightweight masonry mortar.

An essential basic consideration of the present invention is that the stone is manufactured with a changed stone height in a newly defined tolerance, whereby post-processing by grinding - as in the prior art - does not take place. 35

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The previously known flat bricks are also adapted to the required wall dimensions, but their width is set at 124, 249 or 499 millimeters with a tolerance of ± 1 millimeter by grinding. The bricks according to the invention, however, have a brick height of 123 millimeters, 248 millimeters or 498 millimeters, with the tolerance preferably being ±1.5 millimeters. This also makes it possible to process them as flat bricks (with a thin layer of mortar), but no further processing of the brick (grinding) is required.

The drawing shows an example of implementation:
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Fig. 1 shows schematically the structure of a production plant for bricks,

Fig. 2 shows a three-dimensional schematic representation of a brick according to the invention.

Fig. 1 shows schematically how the process for producing a brick works. A material mixture 2 is mixed in a mixing container. This can be clay that has been prepared (see above) and is mixed with sawdust to achieve a high porosity in the finished brick. The material mixture is fed to an extruder nozzle 3, which expels it at an exit speed v. The aim is to achieve as uniform a speed distribution as possible across the nozzle cross-section. The nozzle profiles the material mixture 2 in such a way that the extrudate corresponds to the cross-section of the desired brick.

A cutting device 4 is arranged downstream of the nozzle 3. This is shown schematically in the figure as a frame that is vertically movable. It carries a cutting wire 5 that is stretched by the frame. The frame is lowered in the cutting direction s, whereby a piece of the extruded profile can be cut off. The cutting is carried out in such a way that stone blanks 1 with the brick height H are produced.

In order to achieve a high degree of precision in cutting the cutting wire, the cutting device 4 is moved at the moment of cutting at the nozzle exit speed v, so that - despite the further movement - a straight cut is achieved.

The brick produced in this way can be seen in Fig. 2. The length of the strand was cut with such precision that the brick height H lies within a small tolerance T, with a size of ±1.5 millimeters being the aim. In this case, the brick 1 can be installed directly as a flat brick without further processing (grinding), whereby a mortar layer of approx. 2 millimeters can be provided.

As can be seen in the figure, the stone has several (nine in Fig. 2) cavities 6. These not only serve to save weight and material, they also enable improved thermal insulation. By cutting the stone 1 using the cutting wire 5 in the cutting direction s, cutting burrs 8 have been created on the surface O of the stone 1 in the area of the opening of the cavity 6.

Cutting burrs are generally rather undesirable; in the grinding post-processing according to the state of the art, they are therefore also removed by grinding. The stone according to the invention uses the burrs deliberately. The burr represents a support for the mortar that is applied during the brickwork. This makes it easier to cover the openings 7 of the cavities 6, so that a continuous mortar layer is formed that completely closes the openings 7.
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The stones 1 are cut to the size of the wall. To make it easier to install the stones, they are cut to 123 millimeters, 248 millimeters or 498 millimeters, with a tolerance of no more than ± 2.5 millimeters, preferably ± 1.5 millimeters. This allows for precise positioning using lightweight masonry mortar.

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List of reference symbols:

1 brick 5 2 Material mixture 3 Strand nozzle 4 Cutting device 5 Separating wire 6 cavity 10 7 Opening of the cavity 6 on the surface of the brick 1 8th Cutting burr H Brick height T tolerance 15 &ngr; Nozzle exit speed O
S Surface of brick 1
Cutting direction

Claims (4)

Protection claims 1. Multi-chamber brick (1), in particular made of clay or loam, with cavities (6) extending in the direction of height (H), characterized by - a brick height (H) adapted to the required wall size, - whereby the brick (1) is installed without any further processing, in particular without grinding, and - wherein the openings (7) of the cavities (6) on the surface (O) of the brick (1) have cutting burrs (8). 2. Multi-chamber brick according to claim 1, characterized in that it has a brick height (H) of 123 millimeters, 248 millimeters or 498 millimeters for the purpose of precise positioning with a lightweight masonry mortar with a tolerance of at most ± 2.5 millimeters, preferably ± 1.5 millimeters. 3- Multi-chamber brick according to claim 1 or 2, obtainable by a) production of a material mixture (2), in particular of clay and/or loam with the addition of additives such as sawdust, b) pressing the material mixture through a strand die (3) which corresponds to the profile of the brick (1), c) cutting individual bricks (1) to length as part of the material (2) pressed through the extrusion die (3), while maintaining a small tolerance (T) in such a way that reworking of the brick (1) to achieve a defined brick height (H), in particular by grinding, is not necessary, whereby a brick blank with the desired brick height (H) is produced, and d) Drying the brick blank. 4. Multi-chamber brick according to claim 3, wherein a uniform flow cross-section of the material mixture (2) is maintained over the entire cross-sectional area of the strand nozzle (3).