The invention involves a panel element consisting of a number of boards or beams arranged adjacent to each other and edgewise to the surface of the panel element, whereby wooden dowels are provided, which penetrate all of the panel element's adjacent boards or beams for the purpose of connecting the boards or beams.
Prefabricated ceiling and wall elements, consisting of a number of boards or beams arranged adjacent to each other are already available. The individual boards and/or beams are usually connected by gluing, nailing or screwing two adjacent beams to each other. The disadvantage to these previously known panel elements is that during the natural expansion or contraction of the wood of the individual boards or beams the swelling or shrinkage value accumulates over the entire width of the element, creating relatively large swelling and shrinkage values over all.
Another suggestion already proposed is to connect the adjacent boards or beams with threaded rods, which span entire width of the panel element and are screwed into pre-bored holes. This fixes the individual boards or beams of the panel element to each other in their relative positions and swelling or shrinkage of the wood of a board and/or beam is limited to the respective board and/or beam. In its width dimension (in the longitudinal direction of the thread rods), the ceiling or wall element remains practically unchanged. But the disadvantage to these existing panel elements, as it is with other board or beam connections using metal parts (particularly nails or screws), results from the severe restrictions on the subsequent processing possibilities for this panel element, the ability to saw it, for example. This type of panel element is known under U.S. Pat. No. 3,172,170, for example. Connecting boards or beams arranged adjacent to each other using threaded rods is also described in SU 1 784 723 A1.
A panel element of the type described above is also listed under AT 003 277 U1. In this existing panel element, the connection of the boards or beams is effected with wooden dowels that are spaced in the longitudinal direction of the boards or beams, are located parallel to each other and are arranged perpendicularly to the longitudinal direction of the individual boards or beams. The individual boards or beams are connected relatively loosely. In particular, it is not possible to prevent swelling and shrinking of the total dimension of the panel element. The possibilities for using these panel elements as ceiling and wall elements are therefore limited and/or relatively elaborate measures must be taken during installation to permit changes in the width dimension of the panel elements as they swell and shrink.
The task of the invention is to prepare a panel element of the type mentioned initially in which the change in the total width of the panel element as a result of the swelling and shrinking of the wood of the panel element's individual boards or beams is prevented or is at least minimized. According to the present invention, this is made possible by the fact that these wooden dowels are placed at an angle of a least 15°, preferably 25°, perpendicularly to the side of the boards or beams, whereby suitable wooden dowels are provided in both directions with respect to these perpendicular lines.
Surprisingly, it has been shown that this easily executed measure results in a change in the width of the panel element due to swelling and shrinking of the wood of the individual boards or beams is significantly impeded and/or restricted, whereby a metal-free panel element can be provided that has excellent subsequent workability properties. Another advantage to this invented panel element is that it can also be produced without glue, so that the environmental impact is lessened. The manufacture of the panel element is extremely easy. The adjacently arranged boards or beams are pre-bored and the wooden dowels are driven into the pre-bored holes.
Additional advantages and details of the invention will be explained below on the basis of the preferred construction forms illustrated in the attached drawings. The drawings show:
The design example of an invented panel element illustrated in
The adjacently arranged boards are connected with wooden dowels (3), which are indicated in
To manufacture the panel element the adjacently arranged boards are provided with appropriate bore holes, and the wooden dowels are driven into the pre-bored holes. It is not necessary to use glue. A strong connection is created because when the wooden dowels are driven in the moisture content is less than the moisture content of the panels when installed.
The adjacently arranged boards have molded edges on their abutting sides. These molded edges create stronger connections between the individual boards. In addition, these molded edges make it possible to permit passage openings (6) along the longitudinal direction of the panel elements. Wiring and pipe work can be installed in these openings or steel cables for producing a pre-tensioned ceiling.
The individual boards (1) of the panel element can also have differing widths, as illustrated in
A panel element, according to the invention, can form a load bearing ceiling or wall element. It is also suitable, for example, for producing a wood-concrete composite ceiling. The boards (1) can also be curved along their longitudinal direction. This permits the production of so-called arched-barrel roofs with large free spans, which are preferably trussed with steel cables.
The width of a single panel element can, for instance, range from 50 cm to 80 cm, its thickness, depending on the free span, from between 10 cm and 28 cm. The thickness of a single board can range from 20 and 45 mm, for example.
The wooden dowels can be made of a hardwood such as beech. A softwood such as spruce or pitch pine, for example, can be used for the boards.
Although it is preferable for the wooden dowels (3) to penetrate all boards and/or beams of the panel element; in principle shorter dowels could also be used in addition to those spanning essentially the entire width of the panel element. These shorter dowels would only penetrate some of the boards and/or beams. Besides the wooden dowels that are angled perpendicularly to the sides of the boards, in principle, dowels that are arranged parallel to the perpendicular sides could also be used.