EP0067802B1

EP0067802B1 - Fixing method

Info

Publication number: EP0067802B1
Application number: EP82850131A
Authority: EP
Inventors: Kurt Eklund
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-06-11
Filing date: 1982-06-10
Publication date: 1986-08-13
Also published as: NO821941L; ATE21431T1; SE8103670L; EP0067802A3; DE3272563D1; EP0067802A2

Abstract

A method of fixing sheet metal sections and wooden bars or boards relative to each other, which latter transversely to the longitudinal direction of the sheet metal sections can be inserted into holes punched in the sheet metal sections, at which method after the boards have been inserted into intended holes and after the positions and angles for the sheet metal sections and boards have been aligned relative to each other, the sheet metal sections are pressed together about the boards, so that the sheet metal section after the removal of the pressing force assumes a permanent deformation, while the inserted board or boards elastically spring back so that section and wood permanently are pressed against each other.

Description

This invention relates to a method of fixing a wooden board to a U-shaped metal section, the wooden board extending through a hole in the base part of the U-shaped metal section.
Connections of this type are for instance shown in FR-A-509 051, which concerns a fence constituted by U-shaped horizontal rails and vertical boards. The boards extend through holes in the base part of the U-shaped rails. The boards are however loose and are at their bottoms supported on a solid base of the fence. The resulting fence is due to the lack of fixing between rails and boards rather difficult to use.
A step further in development is exemplified by US-A-3 420 504 and US-A-3 471 128, both documents showing how more or less U- or C-shaped rails (without holes) can be fastened to the ends of vertical members in a fence by compressing the C- or U-shaped rails. If this type of fastening means were to be used to combine metal rails with wooden bars the wooden bars would probably be damaged at the fastening point, resulting in a reduction in strength for the combined structure, or the rails would not be able to hold a wooden bar or board with a sufficient force to ensure a permanent rigid grip.
The object of the invention is to provide a method of joining or fixing wooden boards to a U-shaped metal section that overcomes the set- backs of the known technic, give a very secure grip in a very simple manner without weakening the wooden board where it extends through the metal section. The invention is particularly applicable to the fabrication of fence panels or modules.
The object of the invention is obtained by holding the wooden board and metal section in their intended relative positions, the limbs of the U-shaped metal section are then pressed against the board with a force sufficient to result in a permanent deformation of the base part of the U-shaped section and an elastic deformation of the board, whereby when the pressing operation is terminated the section limbs remain pressed against the board. Since the resilience of the wood is greater than that of the metal in the metal section a remaining stress will result between the metal section and the wooden board.
In accordance with a further development of the above inventive idea, which is particularly suitable for rails, the base part of the metal section has a longitudinal fold giving it an obtuse V-shape so that when the limbs of the sheet metal section are pressed against the broad deformation takes place at the apex of the V giving the metal section a uniform cross-section. In this way the pleasing appearance is obtained with very easy means and furthermore the apex of the V preferably points upwards so that if the metal section is used as a horizontal rail in for instance a fence water will easy be drained off the rail.
In order further to improve the rigidness of the fixing of jointing in accordance with the invention one or both of the hole edges which at the pressing together of the limbs of the U-shaped section are pressed against the board are provided with tips or edges facing towards the wood and that at the compressing stage are pressed into the wood causing a permanent deformation thereof at the lateral edges of the hole. In this way an improved longitudinal fixing as well as angular fixing of the bar in the U-shaped metal section is obtained, It is of course not necessary that the edge penetrating into the wood is straight but one can imagine that one or more small jags or tips project into the hole and give the desired extra grip. Especially when the rail is desired to be slightly angularily movable in order to allow inclined mounting it may be suitable that the portion of the hole edges which penetrate into the wood consist of a short piece at the centre of the hole so that the inserted board easily will allow adjustment of the inclination, with the board still strongly retained in the metal section or rail. This can for instance be the case when the invention is used to fabricate fences that have to adapt to the slope of the ground.
It can, of course, also be imagined within the scope of the invention, that the afore-mentioned section is doubled, i.e. comprises a similar "house" section facing downward and connected directly to the upper one. This embodiment, however, when applied to rails has the disadvantage, that water can be included in the section, unless, for example, the lower holes in the section are dimensioned greater than required for inserting the boards.
Due to the fact, that at the method according to the invention the height of the section, or rather the height of the side flanges has no major effect on how good the engagement between wood and sheet metal section will be, the flange height can be permitted to be determined entirely by the desired strength in vertical direction (it is in this direction the rail runs risk to be subjected to the greatest strains at climbing etc.) and at the same time the transverse dimensions of the rail can be held restricted, thereby rendering possible a good economy, in view of the raw material prices of today.
The invention is described in greater detail in the following, with reference to a practical embodiment thereof shown in the drawings. Fig. 1 is a perspective view of a portion of a rail according to the invention, Fig. 2 is a sectional view of the fixing according to the invention, and Figs. 3 and 4 show further details in the rail shown in Fig. 1.
The rail shown in Fig. 1 comprises a horizontally positioned sheet metal section 1, of which only a short piece is shown. In the sheet metal section a wooden bar 2 has been secured by pressing, in that the sheet metal section has been clamped about the wooden bar 2. This is shown more clearly in Fig. 2 where it can be seen how the sheet metal section 1 when it was pressed together has been folded additionally at the angle point 3, so that the tips or edges 4 and, respectively, 5 for the hole in the sheet metal section, which are located on both sides of the board or wooden bar 2, have been pressed into the wood.
Fig. 1 also shows a rail post assembled of two identical sections 6 and 7. The section parts 6 and 7 include recesses of such design that members 8 bent to V-shape can be inserted, which in their longitudinal direction are fixed by means of recesses 9 and 10 embracing the post sections 6 and 7. When the rail is to be mounted, the section 1 quite simply is laid on the V-shaped member 8 and fixed against being lifted off in that a sleeve 11, which prior to the mounting had been pushed on the sheet metal section 1, is moved to abut the post, in which position it can be fixed in any desired way, for example by some snap-in lock.
In order to hold together the post brought about by the sections 6 and 7, at the upper end a cover can be located which extends over recesses 12 and, respectively, 13 in the upper ends of the sections. The cover may either be clasped on or snapped over the recesses 12, 13. Alternatively the cover 14 can be mounted in the way shown in Fig. 3, i.e. end projections are hooked in the cover whereafter the post parts 6 and 7 are moved together and thereafter inserted down into, for example, an anchorage 15 in the ground of the kind shown in Fig. 4. Of course, instead of using the anchorage 15, the post can be cast in concrete in known manner, but this should generally be a more expensive method, because of the greater amount of labour involved.

Claims

1. A method of fixing a wooden board or bar (2) to a U-shaped metal section (1), the wooden board extending through a hole in the base part of the U-shaped metal section, characterized in that with the wooden board and the metal section held in their intended relative position, the limbs of the U-shaped metal section are pressed against the board with a force sufficient to result in a permanent deformation of the base part of the U-shaped section and an elastic deformation of the board, whereby when the pressing operation is terminated the section limbs remain pressed against the board.

2. A U-shaped sheet metal section (1) for carrying out the method according to claim 1, comprising holes in the base part of the U-shaped section for the receiving of boards (2), characterized in that the base part of the metal section has a longitudinal fold (3) giving it an obtuse V-shape so that when the limbs of the sheet metal section are pressed against the board deformation takes place at the apex of the V giving the metal section a uniform cross section.

3. A sheet metal section as defined in claim 2, characterized in that one or both of the hole edges which at the pressing together of the limbs of the U-shaped section are pressed against the board are provided with tips or edges (4, 5), which face towards the wood and at the pressing together are pressed into the wood, so that a deformation of the wood is obtained at the lateral edges of the hole in order to yield a strong longitudinal fixing of the bar in the section.

4. Railing assembly, characterized in that it comprises as ledgers sheet metal sections (1) according to any of the claims 2-3, with vertical wooden bars inserted into the sections, which bars have been fixed relative to the ledgers by the method defined in claim 1.

5. A railing assembly module, comprising horizontal sheet metal sections (1) of U-shaped cross-section and provided with holes in the base part of the U-shape receiving vertical boards or bars (2) of wood, characterized in that the limbs of the U-shaped metal section have been pressed against the boards or bars with such a force that the sheet metal sections are permanently deformed even after the removal of the pressing force, so that the edges (4, 5) of the holes in the sheet metal sections are pressed into the wood ensuring a good fixing of the module and the limbs remain pressed against the boards or bars.