The invention relates to a building unit in the form of a plane unit of acute-angled triangular shape. Acute-angled means that the outer limits of the unit are sides in a triangle having acute angles, i.e. angles less than 90°.

There are known several different forms of triangular building units which can be connected to form one or more different articles for everyday use or for decoration by connecting a number of uniform units.

It is the object of the present invention to provide a building unit which may both be used separately, in pairs and which is suitable for being connected in a number so that it is thereby possible to form many different forms of articles for everyday use or for decoration particularly articles which may be used as household goods or in connection with household goods, as units in connection with house building, as toys etc.

This is achieved by designing the building unit according to the invention as disclosed in the characterising part of claim 1. There is thus obtain¬ ed a very simple unit which due to its particular geometrical shape may be connected in innumerable ways and form many different figures for use for various purposes. The building unit may be designed so as to have little weight but nevertheless suffici¬ ent strength to any. desired applications, and the building unit is moreover designed in such a manner

that it may be used separately or be connected with other corresponding building units without all the building units which are to be connected requiring exactly the same shape.

By designing the building unit according to the in¬ vention as disclosed in the characterising part of claim 2, there is obtained a unit having a harmonic appearance in that the opening in the unit gets the same shape as the unit itself. This design will more¬ over permit the application of many different gene¬ rally known connecting methods and permit manufactur¬ ing of the unit in a rational manner so that manufac¬ turing costs are reduced. The cross-sectional profile of the crosspieces thereby becomes rhomb-shaped, pre¬ ferably as an equilateral rhomb.

Depending on whether the crosspieces are of the same or different lengths it is possible by connecting a number of building units to form a number of differ¬ ent figures or household articles. For example, two building units may be connected so that two outer edge faces of each of the units are in two planes at right angles to each other.

The building unit according to the invention is for example designed as disclosed in the characterising part of claim 3. It is possible to use other angles than those mentioned in the claim but with the stated angles there is obtained an equilateral building unit which is simple in use, for example in or at a cor¬ ner, against or on a plane surface such as a wall, or which can form a complete spatial figure because of the equilateral form of the unit.

By designing the building unit according to the in¬ vention as disclosed in the characterising part of claim 4, there is obtained a very simple and discreet connecting method in that the connecting means are preferably provided on or in a normally rearwardly facing side.

If the building unit according to the invention is designed as disclosed in the characterising part of claim 5, the bores may be used for connecting the units to each other as well as for screw holes for for example fixing the units to a wall. Moreover, the visible edges of the bores form part of the decorati- ve appearance of the building unit.

If the connecting means of the building unit accord¬ ing to the invention are designed as disclosed in the characterising part of claim 6, the need for visible connecting means on the normally outwardly facing side is avoided.

The building unit according to the invention may be manufactured as disclosed in the characterising part of claim 7 by starting with a sheet material which is machined. This will permit manufacturing of the building unit according to the invention by two pro¬ cess steps, viz. by a cutting of the outer profile and a subsequent machining of the internal profile. There is thus obtained a very fast and automated manufacturing process in that the entire manufactur¬ ing may proceed on programmed machine tools.

The building unit according to the invention may find

use for a great number of different household ar¬ ticles such as household articles as disclosed in claims 8, 9 and 10.

The invention will be further explained in the following with reference to the drawing wherein

Fig. 1 is a building unit according to a first embodiment viewed from one side,

Fig. 2 is the same building unit viewed from the other side,

Fig. 3 is a plane cross-section of a crosspiece in Fig. 2,

Fig. 4 is a plane section corresponding to Fig. 3 but in another embodiment of the building unit,

Fig. 5 is the other embodiment viewed from one side,

Fig. 6 is the same building unit as in Fig. 5 but viewed from the other side,

Fig. 7 is two building units as a shelf bracket,

Fig. 8 is two building units as a shelf support,

Fig. 9 is a number of building units forming a spatial figure,

Fig. 10 is two building units forming a basket or

the like, and

Fig. 11 is another embodiment of the unit shown in Fig. 2 and at a larger scale.

The building unit shown in Figs. 1-3 ^" consists of three integral rods, beams or crosspieces 3 made of for example plastics, steel, concrete, wood or fibre material. Fig. 1 shows the unit viewed from what would generally be termed the front, and Fig. 2 is a rear view of the unit. In the centre of the unit there is a through-opening of triangular shape with rounded corners since the inwardly facing edge faces 8' are produced by milling. In the three crosspieces there are a number of bores 9, for example three bores in each crosspiece placed at intervals of a quarter of the length of the crosspiece. The building unit 1 is equilateral and the angles v and u in the cross-sectional profile shown in Fig. 3 will be 35,264° and 144,736° which by usual manufacturing tolerances may be reckoned as approx. 35,3° and 144,7° which angles are situated between the edge faces 7 and 8 where 8 is the outer edge face and 8' is the inner edge face and where the sides 7 are mutually parallel just as the sides 8 and 8' are mutually parallel.

The building unit 2 shown in Figs. 4-6 is designed in a manner similar to the building unit shown in Figs. 1-3 but the crosspieces 4, 5 and 6 are of unequal length. This produces the result that the cross- sectional profile becomes different in the three crosspieces. The bevelled angles u and v will there¬ fore not have the same angle as by equilateral units

but by a suitable choice of the angles u and v dependent on the relative lengths of the crosspieces it is possible to still make the planes wherein the edge faces 8 of the unit are situated intersect each other at an angle of 90°.

The through-bores 9 are made at right angles to the edge faces 8 and 8' and arranged symmetrically there¬ by permitting connection of two units edge to edge as shown in Fig. 7, pins or screws 15 being mounted in the bores 9. The two building units 1 shown form a shelf bracket which may be fixed to a wall by means of screws mounted in the bores in the crosspieces resting against the wall (the plane of the paper) and a shelf 10 may likewise be secured by means of pins in the bores 9 which pins engage holes in the under¬ side of the shelf 10.

The simplest application is to place a single unit in a corner as a bracket for a corner shelf.

The geometrical design of the crosspieces is such that the crosspieces supporting the shelf in Fig. 7 will have their outwardly facing edge face 8 situated in a common plane corresponding to the plane of the shelf 10.

The building unit may also be used as shown in Fig. 8 where the bores 9 facing each other are used for re- taining a couple of bars 12 which may for example be used as supports for hangers and the like or have a decorative effect. Apart from the upper shelf 10 it is possible inside the structure to mount a further shelf 11.

Fig. 9 of the drawing shows a lamp suspended in a wire 14, said lamp being designed by a number of building units of somewhat different design in that the upper building units 1 are equilateral and of the kind shown in Figs. 1-3 whereas the building units 2 arranged thereunder are of the kind shown in Figs. 4- 6 of the drawing. In the triangular openings there may be provided glass or similar translucent material.

If equilateral building units are used, eight units may form a regular octahedron. If isosceles building units are used, two different octahedrons may be formed by eight units, and if units where all sides are of different lengths are used, eight units may form three different octahedrons.

Fig. 10 shows a suspension basket composed by two building units of the type shown in Figs. 4-6 wherein the short sides are joined and the longer sides define the limit against a wall and define the up¬ wardly directed opening of the basket, respectively. In the triangular openings there is provided sheet material 13.

Fig. 11 shows a further embodiment of the connecting means in that projections 16 with through-bores 17 in transverse direction may hold ₍ together the units by means of pins or screws in the bores. The projections are substantially parallel to the outer edge face 8 and form an integral part of the side 7. In this man¬ ner the connecting means will not be visible on the outer side. The connecting means 16 may for example

also be used for retaining various fillings in the central opening.

The building unit according to the invention is pre- ferably manufactured by cutting in the usual manner a sheet material with the required thickness into triangular sheet-formed objects which are then machined by moulding or cutting so as to form the in¬ wardly directed edge faces 8' . There is thus obtained rounded internal corners in that the rounding is determined by the diametre and shape of the cutting or moulding tool.

It is obvious that if the building unit according to the invention is to be manufactured of a plastic material, the most advantageous procedure would be to produce the unit by injection moulding but this will require a complete mould for each size and for each type of building unit. By production by means of a programmed moulding or cutting machine it is possible by simply using a program to determine the size and shape of the individual building unit thus simplify¬ ing the manufacturing process and permitting a quick change of production. Particularly the embodiment according to Fig. 11 is advantageous for injection moulding in plastics to form a unit.

The building unit according to the invention may be produced in small dimensions, e.g. for toys or toy systems, in larger dimensions, e.g. for household articles as mentioned in connection with Figs. 7-10 of the drawing, or in very large dimensions, e.g. as wood, concrete or iron/steel units for house building whether as supporting units as well as decorative

units such as facade panels, special rafter struc¬ tures etc.