DE2021894A1 - Spacer for concrete iron - Google Patents

Description

PATENT LAWYERS

DR. CLAUS REIMLÄNDER

DIPL ING. KLAUS BERNHARDT 2021 894

D-8 MÖNCHEN OO • XCKERSTRASSf *

206/2

N.7. Plastics industry Attema Sehelluinsestraat 68
Gorinchem, Netherlands

Spacers for concrete iron

Priority? March 26, 1970 Great Britain 14997/70

It is known to use concrete reinforcing bars or mesh reinforcement in a formwork \ to support it in a certain Distance from the formwork wall, with the help of spacers Made of plastic material to hold.

In the South African patent specification 68/4712, such a spacer is described, which contains a body made of plastic material with a clamping site for a reinforcing bar and which has a BrÜokenstÜck, which is connected on the one hand with support brackets and on the other hand with one or more clamping arches, each of which is over essentially its entire length is resilient and is reversed inwardly into an almost closed shape, the free end of which is provided with a clamping toothing lit.

The support legs according to this patent specification have a main plane of symmetry which coincides with that of the clamping arch or arches and form a solid unit with the bridge piece and these arches. Although such spacers are an effective

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same support of the reinforcing bars may have resulted they still have some disadvantages.

On the one hand, the lateral stability is perpendicular to the median plane, i.e. in the direction of the reinforcing bars to be supported, quite small, which in practice can inhibit the introduction of a rod when it is in the clamping part of a spacer rod that is attached to the formwork, as the spacer is then easily turned over · The same can be done with a Series of Abatandsstüoken happen that are already clamped on a rod when longitudinal forces are exerted on this rod e.g. in the pail of a vertical formwork during pouring of the liquid concrete or during handling of a complete reinforcement network, resulting in an inaccurate Distance between the rod and the formwork leads or requires additional work.

Furthermore, eich has shown that the adhesion between the concrete and the plastic material of such spacers is poor » '.-', ■ - <'» oils Abgtandssttteke according to the above-mentioned patent specification eis® result in a significant improvement in relation to earlier spacers, that the concrete flows freely through the relatively large openings of the spacer pieces, so that these spacers are clearly anchored in the concrete after it has set, the contact surface with the formwork is still quite large, so that it is possible that water after removing the soil slowly migrates into the concrete from the outside along the transition between the legs of a spacer and the concrete, the transition at the surface of the concrete being of relatively great length. This can cause the rebars to rust and lose their strength.

The invention creates an improvement in such distances in that the legs of the spacer © according to the invention have the shape of a cross or star, the main plane of which is substantially perpendicular to the central plane of the clamping arcs

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stands whose arms, or at least the majority of them, are in at an angle relative to the latter plane, the center of which is connected to the bridge part and the ends of these arms on the side remote from the bridge part with small protruding lugs for Touching the formwork and the entire contact area of these approaches with the formwork is sufficient » to support the reinforcement, but otherwise as small as possible * In addition, the thickness of the material of the Feet can be significantly reduced compared to the thickness of the feet according to the above-mentioned South African patent specification » which leads to better embedding and less disruption of the concrete.

In the middle of the cross immediately below the connection an additional approach can be provided between the cross arms and the bridge part «

The invention will now be described in detail by way of example with reference to the drawing in the Pig. 1 and 2 one Front view and a bottom view of a spacer according to show the invention.

The preferred embodiment illustrated includes one piece made of plastic material. On one part of the bridge 1 there are four legs 2 in the shape of a right-angled cross and " on the other hand, two flexible clamping arcs 3 »the toothed one Claws 4 ends «attached. These claws can also be shaped in another way »e.g. as in the one mentioned above South African patent document shown.

The legs 2 are at their lower surface and close to the outer ends provided with small projections 5 "which have a contact surface with the formwork wall 6" which are so small anything is possible. A similar approach 5 is also provided in the middle of the cross.

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As described in the above-mentioned patent specification, a reinforcing bar can be clamped between the claws 4 and the weight to be supported is divided between the contact lugs 5. Since the legs 2, which the arms of a cross can "extend at an angle with respect to the main plane of these claws" Forces that act in a single direction that the spacer would be turned over, are sufficiently counteracted. It also puts the strain on everyone Approach decreased to such an extent that after removing the formwork only a very small TeUJ. the concrete surface is interrupted, resulting in a substantial reduction in the risk of water wall ems in the concrete leads.

The number of legs 2 is of course not limited to four, provided that their majority in one Angle with respect to the main plane of the claws 3 is directed.

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Claims (2)

206/2 Expectations My spacer for bars for reinforced concrete with a body made of plastic material, which has a clamping seat for a reinforcing bar to be supported in the form of one or more μ clamping arcs and support legs for the seat connected to it by means of a bridge piece «characterized in that the legs in the form a cross or star are arranged, the main plane of which is substantially perpendicular to the median plane of the clamping arcs, at least the majority of these arms being arranged at an angle relative to the latter plane and the center of which is connected to the bridge part and the ends of these arms at the from the side remote from the bridge piece are provided with small protruding lugs for touching the formwork. 2. The spacer of claim 1, characterized by an additional approach to the center of the crossed arms · ä 109841/1026 Blank page