EP3708728A1 - Friction plate for a wood joint - Google Patents

Abstract

Friction plate (1) for a wood connection (5) between a first connection element (7) made of wood and a second connection element (9), with a plate-shaped carrier (1T) with a first carrier connection side (1ETAS) for flat connection to the first connection element (7 ) and a second carrier connection side (1ZTAS) for flat connection to the second connection element (9), as well as a roughening (3) of at least one section of the first and / or second carrier connection side (1ETAS, 1ZTAS).

Description

The invention relates to a friction plate for a wood connection and a wood connection formed with the friction plate.

It is known to connect wooden beams with butt joints by means of a shear or lap shear connection. For example, one end of a bar is attached to another bar at a 0 to 90 ° angle and fastened there with screws or other pin-shaped connecting means. The screws can be screwed through both or more beams at an angle, in particular at a 90 ° angle from the side opposite the one beam.

It is also known to fasten wooden beams to a concrete wall or to a metal plate, for example a wooden connector. For this purpose, for example, screws or pin-shaped fasteners are screwed through the wood and then into the concrete wall or into the metal plate.

The disadvantage of wood connections is that the loads that hold the connections are too low and higher loads or higher stiffnesses are desired.

The object of the present invention is therefore to increase the load-bearing capacity and / or the rigidity of wood connections.

The object is achieved according to the invention by a friction plate with the features of claim 1 and a wood connection created with the friction plate according to the further main claim.

The first and second connection elements bear against one another at a connection point, the friction plate being arranged between them. The connection elements are preferably located at the connection point over the entire surface of the friction plate, so the connection elements at the connection point bear as flat as possible on the friction plate. However, it is possible for sections of the connection elements to lie directly against one another. The wood connection between the first connection element, the friction plate and the second connection element that is created at the connection point is held together by fastening elements, in particular wood screws. The fastening elements thus press the connection elements against the friction plate with a certain contact pressure. Due to the roughening of the respective carrier connection side of the friction plate, the respective connection element rests against the friction plate with a higher static friction than the first connection element made of wood would rest against the second connection element in a wood connection without a friction plate. The static friction between the elements involved, which is increased by the friction plate, counteracts a displacement of the elements relative to one another, ie the initial displacement of the connecting elements relative to one another is made more difficult. A relative displacement of the elements to one another therefore only takes place with increased loads compared to a wood connection without a friction plate. The roughening of the carrier connection sides of the friction plate can take place by means of projections or depressions, for example millings. It is crucial that only the roughness of the respective carrier connection side is increased, whereby the static friction with the connection elements to be connected is increased. This is in contrast to metal plates for wood connections that have protrusions, for example in the form of hooks, which penetrate the wood. It is precisely this penetration of projections that is to be avoided in the plate according to the invention, but only the static friction between the elements to be connected, ie the two connection elements and the friction plate, is to be increased.

If one compares the load-bearing capacities of two structurally identical wood connections (comprising a first connection element made of wood, a second connection element and fastening elements to hold the connection elements together), in which a wood connection with and a wood connection is formed between the connection elements without the friction plate, the Friction plate - with the same contact pressure through the fastening elements - for a higher static friction between the elements and thus for a higher load because the "slipping" of the elements relative to one another only occurs at higher loads.

The carrier of the friction plate can consist of a metal, for example aluminum or steel, in particular stainless steel, or plastic, in particular a glass fiber reinforced plastic, a laminate, fleece or multi-layer paper, for example single-sided or double-sided sandpaper.

If the carrier consists of plastic, laminate, fleece or multi-layer paper, roughening can be introduced into the carrier, for example by embedding small balls in it. So, for example. Small stones, small balls made of a hard plastic, small broken glass or the like. be embedded in the carrier. It is crucial that these balls are sufficiently hard on the one hand that they are not pressed together by the contact pressure and on the other hand protrude from the carrier in a sufficiently small manner to merely increase the static friction with the connection element.

The first connection element can, for example, be a wooden beam, in particular for roof construction, for example a carrier.

The second connection element can consist of wood, in particular a wooden beam, or consist of steel, for example a steel beam, or a wall section of a building, for example of masonry or concrete.

The friction plate according to the invention is thus suitable for wood connections between a connection element made of wood and a further connection element, which can be made of wood, steel, concrete or masonry. Fastening elements, for example screws, hold the first and the second connection element, between which the friction plate is arranged, to one another.

The roughening can be formed on one carrier connection side or on both carrier connection sides of the friction plate.

The friction plate has a first carrier connection side for contact with the first connection element and a second carrier connection side for contact with the second connection element. The roughening can be formed on both sides or on one side. In the first case, a roughened carrier connection side is in contact with a connection element. In the second In this case, the friction plate has only one roughened carrier connection side with which it rests against a connection element. In this variant, the opposite, non-roughened carrier connection side is preferably firmly connected to the other connection element, for example the friction plate with the smooth carrier connection side can be firmly connected to a connection element before the wood connection is joined, for example screwed there, so that the Friction plate is prevented relative to this connection element.

This variant is particularly preferred in applications in which a metal component is firmly connected to a connection element, for example a joist hanger is firmly connected to a connection element, for example is screwed to it. An outside of the joist hanger, which is then intended to rest on the other connection element to form the wood connection, has the roughening in order to increase the increased static friction between the joist hanger and the connecting element attached to it - the joist hanger is already there with the other connection element firmly connected, e.g. screwed.

The roughening is advantageously formed in at least one section of the respective carrier connection side and preferably fills the entire carrier connection side. However, it is sufficient for the formation of the wood connection if the roughening is formed in the section of the carrier connection side with which the friction plate rests on the respective connection element, but preferably at least half of this surface is roughened in order to achieve a higher static friction and thus a higher load capacity to reach.

In a first variant, the roughening is formed in at least one section by projections, for example ring-shaped or pyramidal or conical, these being preferably arranged in a matrix-like manner.

In a second variant, the roughening is formed in at least one section by millings, for example in the form of a line.

The different types of roughening, for example protrusions and millings, can occur separately or in a mixed form. Thus, for example, only projections can be formed in one section of a carrier connection side and only milled recesses in another section be. However, projections and milled recesses can also be formed in a section of a carrier connection side.

If the friction plate has pre-punched holes for the passage of fastening elements, the burr that occurs during punching is preferably sufficient as a roughening. Alternatively, the roughening, for example linear depressions, can already be introduced when the sheet metal is rolled to produce the friction plate. Elements forming a roughening can also be firmly attached to a smooth carrier of a friction plate. For example, sandpaper can be glued to one side of a carrier of the friction plate in order to form the roughening. Fabrics can also be firmly glued to a carrier connection side of a carrier in order to form the roughening.

The carrier preferably has a thickness of 0.2 to 12 mm, in particular 0.5 to 4 mm. The roughening of the respective carrier connection side, for example in the form of projections or milled lines, has a height or depth of 0.1 to 3 mm, in particular 0.5 to 1.5 mm, compared to the surface of the respective carrier connection side.

Since the roughening thus only stands out slightly from the surface of the respective carrier connection side, only the static friction is increased when the roughening is applied to the connection element. When creating the wood connection, in particular when tightening the fastening elements, no force is used to press the roughening into the wood.

The friction plate advantageously has at least one through hole in order to guide a fastening element, in particular a wood screw, through it when the wood connection is formed.

The friction plate can also or alternatively be drilled through by a wood screw, in particular a self-drilling wood screw, without pre-drilling. So that the friction plate can be drilled through by a wood screw without pre-drilling, many parameters can be selected appropriately: For example, the material from which the carrier of the friction plate is made can be be chosen appropriately. Here, for example, plastics or soft metals such as aluminum are suitable. As an alternative or in addition, the thickness of the carrier can be suitably selected so that it can be easily drilled through, for example the thickness of the carrier can be less than 3 mm.

The at least one fastening element is advantageously formed by screws, in particular wood screws, further in particular self-drilling wood screws, and / or drill rod anchors, in particular self-drilling drill rod anchors.

Fig. 1

a) eine Querschnitts- und b) eine Draufsicht einer erfindungsgemäßen Reibplatte,

Fig. 2

a) eine Draufsicht und b) eine Seitenansicht und c) eine Querschnittsansicht eines Scheranschlusses mit der Reibplatte der Fig. 1,

Fig. 3

a) eine Seitenansicht und b) eine Querschnittsansicht und c) eine Draufsicht mit einer Reibplatte wie in Fig. 1, jedoch mit einer anderen Grundfläche,

Fig. 4

a) eine erste Seitenansicht und b) eine zweite Seitenansicht und c) eine Draufsicht auf einen Balkenschuh mit einer erfindungsgemäßen Reibplatte in einer weiteren Ausführungsform,

Fig. 5

a) eine erste Querschnittsansicht und b) eine Seitenansicht und c) eine Draufsicht auf eine Holzverbindung mit dem Balkenschuh der Fig. 4,

Fig. 6

a) eine Querschnittsansicht und b) eine Draufsicht auf eine erfindungsgemäße Reibplatte in einer weiteren Ausführungsform, und

Fig. 7

die Reibplatte der Fig. 6 zwischen zwei Anschlusselementen aus Holz zur Bildung einer Holzverbindung.

Further features, details and advantages of the invention emerge from the claims and the following description of preferred embodiments as well as from the drawing. Show it:

Fig. 1

a) a cross-sectional and b) a top view of a friction plate according to the invention,

Fig. 2

a) a top view and b) a side view and c) a cross-sectional view of a shear connection with the friction plate of FIG Fig. 1 ,

Fig. 3

a) a side view and b) a cross-sectional view and c) a plan view with a friction plate as in FIG Fig. 1 , but with a different base area,

Fig. 4

a) a first side view and b) a second side view and c) a top view of a joist hanger with a friction plate according to the invention in a further embodiment,

Fig. 5

a) a first cross-sectional view and b) a side view and c) a top view of a wood connection with the joist hanger of Fig. 4 ,

Fig. 6

a) a cross-sectional view and b) a plan view of a friction plate according to the invention in a further embodiment, and

Fig. 7

the friction plate of the Fig. 6 between two connection elements made of wood to form a wood connection.

Fig. 1a ) shows a cross-sectional view and Figure 1b ) a plan view of a friction plate 1 according to the invention in a first embodiment with a carrier 1T and a roughening 3 in the form of projections 3V. The friction plate 1 has two opposite side surfaces as the first and second carrier connection side 1ETAS, 1ZTAS for connection to a respective connection element 7, 9 (in Fig. 1 not shown).

The friction plate 1 is made of stainless steel and has through holes 1D for the passage of fastening elements 11 (in Fig. 1 not shown), the through-holes being punched in the friction plate 1. The through holes 1D were punched in the friction plate 1 in such a way that each through hole has an annular collar as a protrusion 3V. The projections 3V form the roughness 3 of the respective carrier connection side 1ETAS, 1ZTAS. The through holes 1D and thus the projections 3V are arranged in a matrix-like manner, the projections 3V projecting alternately from both carrier connection sides 1ETAS, 1ZTAS.

The carrier 1T of the friction plate 1 has a thickness of 0.8 mm. The projections 3V protrude by 0.25 mm from the surface 1O of the respective carrier connection sides 1ETAS, 1ZTAS.

Fig. 2 shows a wood connection 5 with a first and a second connection element 7, 9, with the friction plate 1 between them Fig. 1 is arranged. The first and the second connection element 7, 9 are each a wooden beam. The two connection elements 7, 9 lie flat against one another in the region of one of their respective ends. Like the one in particular Figure 2b ), the connection elements are in contact with one another with a surface that is larger than the friction plate 1. As in Figures 2a) and 2c ), the friction plate 1 is fastened to the connection element 7 with a nail 13 and a wood screw 11 is screwed through the other connection element 9 and through a through hole 1D in the friction plate 1 into the connection element 7. The wood screw 11 is a self-drilling wood screw and is sunk flush in the connection element 9. A thread of the wood screw 11 is arranged completely in the connection element 7 and a threadless shaft is arranged completely in the connection element 9, so that a head of the wood screw 9 presses the connection element 9 against the connection element 7. In Fig. 2 only a wood screw 11 is shown, which presses the connection elements 7, 9 against one another. Further wood screws 11 can be screwed through the connection elements 7, 9 and the friction plate 1 in order to hold them together, depending on the application or the loads.

Fig. 3 shows a wood connection 5 between two wooden beams as connecting elements 7, 9, between which a friction plate 1 is arranged. While the connection element 7, 9 in the Fig. 2 run parallel to each other, the connection elements 7, 9 close Fig. 3 an angle of around 135 ° with each other. The friction plate 1 of the Fig. 3 is analogous to the friction plate 1 of the Fig. 1 constructed, but has a trapezoidal base area instead of a square one. As in Fig. 2a ), the protrusions 3V forming through holes 1D are arranged in two rows through which wood screws 11 are screwed, such as in particular the Figures 3b) and 3c ) can be found. How to Fig. 2 described, the thread of the wood screws 11 is completely arranged in one connection element 7 and the threadless shank of the wood screws completely in the other connection element 9, the friction plate 1 again being arranged between these and the wood screws being screwed through through holes 1D.

Fig. 4 shows a joist hanger 15 made of steel in three views. Like the one in particular Figures 4b) and 4c ) can be seen, 15 through holes 1D are arranged in a matrix-like manner in one side of the joist hanger, which form projections 3V, as described above. Figure 4b ) shows four through holes 1D in two opposite sides of the hanger bracket 15 which do not form any projections 3V.

Fig. 5 shows the joist hanger 15 of Fig. 4 , wherein a first connection element 7 in the form of a wooden beam is inserted into the beam hanger 15 in order to connect it at a 90 ° angle to a further connection element 9 in the form of a wooden beam. The connection element 7 is fastened in the joist hanger 15 in that wood screws 11 pass through the through holes 1D of the opposite sides of the joist hanger 15 which do not form any projections 3V, see FIG. in particular Figure 5c ). Wood screws 11 are screwed into the further connection element 9 through the through holes 1D of the joist hanger 15, which form projections 3V. The side surface of the joist hanger 15 with projections 3V, which rests on the connection element 9, forms a friction plate 1. The friction plate 1 differs from the ones described above in that, on the one hand, the roughening 3 is only formed on one carrier connection side 1ETAS (and the other carrier connection side 1ZTAS has no roughening 3) and, on the other hand, the friction plate 1 is an integral part of another component, in the present case it forms a part or section of the joist hanger 15.

Fig. 6 shows a further embodiment of the friction plate 1 according to the invention. The friction plate 1 in the present case has a carrier 1T made of plastic. When casting the carrier 1T, small stones 17 were also poured in, so that the stones 17 are enclosed by and held by the plastic. The stones 17 are cast irregularly in the carrier 1T, such as the one in particular Figure 6b ) can be found.

The plastic from which the carrier 1T is cast is in the present case a hard plastic so that the carrier 1T is rigid. However, it is also possible to use a soft plastic so that the carrier 1T can be rolled up. In this variant, the friction plate 1 can be in the form of a roll, from which the required pieces can be separated in the desired size.

The carrier 1T of the friction plate 1 has a thickness of 1.5 mm. The stones have a maximum size of 2.5 mm, so that they do not protrude more than 1 mm from a surface 10 of the support.

Fig. 7 shows a wood connection 5 between two connection elements 7, 9 (each a wooden beam), with the friction plate 1 between them Fig. 6 is arranged. To create the wood connection 5, the wooden beams 7, 9 were placed against one another and the friction plate 1 was arranged between them. Wood screws 11 were then drilled through the connection element 7 and the friction plate 1 into the connection element 9. Pre-drilling the connection elements 7, 9 or the friction plate 1 is not necessary because the wood screws 11 are self-drilling. The wood screws can easily penetrate the friction plate 1, since the friction plate 1 consists on the one hand of plastic and on the other hand is only thin.

In the embodiments described above, the friction plate 1 is described in such a way that a plurality of fastening elements 11 can be guided through it. However, it is possible to manufacture the friction plate 1 circular, for example with a diameter of less than 15 cm, in particular less than 10 cm, or square, for example with an edge length of less than 15 cm, in particular less than 10 cm. In this embodiment, friction plates 1 can be arranged at selected points of a wood connection 5 and a fastening element 11 can be guided through them in order to increase the static friction only at these selected points. One or more such friction plates 1 can be arranged between the two connection elements 7, 9. additionally one or more friction plates 1 of the embodiments described above according to FIGS Figures 1 to 7 can be used.

Thus, several identical or also several different friction plates 1 can be arranged between the connection elements 7, 9 in order to form the wood connection 5.

List of reference symbols

1

Friction plate

1D

Through hole

1T

carrier

1ETAS

first carrier connection side

1O

Surface of the carrier

1ZTAS

second carrier connection side

3

roughening

3V

head Start

5

Wood connection

7th

first connection element made of wood

9

second connection element

11

Fastener

13

nail

15th

Joist hanger

17th

stone

Claims (13)

Friction plate (1) for a wood connection (5) between a first connection element (7) made of wood and a second connection element (9), with a plate-shaped carrier (1T) with a first carrier connection side (1ETAS) for flat connection to the first connection element (7 ) and a second carrier connection side (1ZTAS) for flat connection to the second connection element (9), as well as a roughening (3) of at least one section of the first and / or second carrier connection side (1ETAS, 1ZTAS). Friction plate according to claim 1, characterized in that the carrier (1T) is made of a metal, e.g. aluminum or steel, in particular stainless steel, or plastic, in particular a glass fiber reinforced plastic, a laminate, fleece or multi-layer paper, e.g. one or two-sided sandpaper, consists. Friction plate according to Claim 1 or 2, characterized in that the first connection element (7) is a wooden beam, in particular for roof construction, for example a carrier. Friction plate according to one of the preceding claims, characterized in that the second connection element (9) consists of wood, in particular a wooden beam, or consists of steel, e.g. is a steel girder, or a wall section of a building, e.g. made of masonry or from Concrete, is. Friction plate according to one of the preceding claims, characterized in that the roughening (3) is formed on one carrier connection side (1ETAS; 1ZTAS) or on both carrier connection sides (1ETAS, 1ZTAS). Friction plate according to one of the preceding claims, characterized in that the roughening (3) is formed in at least one section of the respective carrier connection side (1ETAS, 1ZTAS), preferably fills the entire carrier connection side (1ETAS, 1ZTAS), or in the section of the carrier connection side (1ETAS , 1ZTAS) has a roughness (3) with which it rests on the connection element (7, 9), but preferably at least half of this area. Friction plate according to one of the preceding claims, characterized in that the roughening (3) is formed in at least one section by projections (3V), for example ring-shaped or pyramidal or conical, these being preferably arranged in a matrix-like manner. Friction plate according to one of the preceding claims, characterized in that the roughening (3) is formed in at least one section by millings, for example in the form of a line. Friction plate according to one of the preceding claims, characterized in that the carrier (1T) has a thickness of 0.2 to 12 mm, in particular from 0.5 to 4 mm, and the roughening (3), for example the projections (3V) or the milled lines, opposite the surface (1O) of the respective carrier connection side (1ETAS, 1ZTAS) has a height or depth of 0.1 to 3 mm, in particular from 0.5 to 1.5 mm. Friction plate according to one of the preceding claims, characterized by at least one through hole (1D) in order to guide a fastening element (11), in particular a wood screw, through it when the wood connection (5) is formed. Friction plate according to one of the preceding claims, characterized in that the friction plate (1) can be drilled through by a wood screw (11), in particular a self-drilling wood screw, without pre-drilling, for example by a suitable choice of the material from which the carrier (1T) is made , for example. Plastic or aluminum, and / or by a suitable thickness of the carrier (1T), for example less than 3mm. Wood connection between a first connection element (7) made of wood and a second connection element (9), wherein a friction plate (1) according to one of the preceding claims is arranged between the first and the second connection element (7, 9), and at least one fastening element (11) ) for holding the friction plate (1) and the first and the second connection element (7, 9) together. Wood connection according to the preceding claim, characterized in that the at least one fastening element (11) is formed by screws, in particular wood screws, further in particular self-drilling wood screws, and / or drill rod anchors, in particular self-drilling drill rod anchors.

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