PRIOR ART AND PROBLEMS When string, selling and/or transporting structures which for the most part consist of boards which are joined at an angle to one another so that they form e. g. (book) shelves, boxes, containers, building structures etc., it is a major disadvantage that these structures take up so much room. A large part of the space they require is taken up by the intermediate spaces between the boards. It is therefore an avantage if the structure can be sold/transported in a nos joined state, the boards being stacked with the wide sides against one another and held together by cardboard, tape or the like. The structure thereby also becomes cheaper for the purchaser, since it requires less space in storage rooms, lorries etc. and since he does not have to pay for the work of putting the structure together. However, with many conventional systems this also signifies a disadvantage for the purchaser/user when he himself has to carry out the actual assembly, which is often labour-intensive and difficult and requires access to various equipment such as tools, screws, glue or the like.

A cabinet structure is known from US 5,527,103 which is assembled without mechanical fastening devices or glue. The side walls in the cabinet have recesses close to the short ends which extend over half the width of the wall and which are sufficiently wide to receive the next wall at right angles, the recesses in two walls being capable of being inserted into one another so far that the recesses will overlap the remaining part of the width of the walls. In the corner, however, the short ends of the walls will stick out somewhat, giving a clumsy impression. The walls must also be secured relative to one another by a bottom and a top, which are preassembled and shaped according to the protruding short ends of the walls.

DE 32 42 884-A1 shows a box to be used as furniture, which box requires mechanical fastening devices on assembly. The various side walls in the box are provided with grooves or battens for insertion into one another and are secured to one another by means of clips which are designed to be placed over the edge on a wall and inserted into a notch in the next wall.

ACCOUNT OF THE INVENTION The present invention presents a joining system which is easy for the user to utilize when assembling a structure, comprising assembly of two boards at an angle to one another, preferably essentially at right angles to one another, and which are designed for joining according to the joining system. The system does not require any tools, mechanical fastening devices, glue or the like and the structure can also be dismantled and reassembled an unlimited number of times. In addition, the joining system gives the structure an aesthetically pleasing appearance.

According to the invention, two boards are joined at an angle to one another, a) a first area of a first board being joined at an angle to a first area of a second board, b) a second area of the first board being joined at an angle to a second area of the second board, c) said first board having a recess in its first area, which recess has a width, in the longitudinal direction of the first board, which width is adapted to receiving the thickness of the second board, d) said second board having a recess in its second area, which recess has a width, in the longitudinal direction of the second board, which width is adapted to receiving the thickness of the first board.

The invention is characterized in that e) the recess in said first board has a groove or a batten which is matched by a batten or a groove in the first area of said second board, and preferably also in that f) the recess in said second board has a groove or a batten which is matched by a batten or a groove in the second area of said first board, the boards, when they are joined, being brought together in said recesses and secured to one another by means of the insertion of said battens into said grooves.

On joining, the recesses in the two boards will be inserted into one another so far that the recesses will overlap the remaining part of the width of the boards, the boards being of the same width in the main, and a total length of the two recesses corresponding to the width of the boards.

According to one aspect of the invention, the boards to be joined consist preferably of wood or veneer-clad particle boards.

According to another aspect of the invention, when this is used for joining a shelving system, e. g. a bookcase, the joining system is utilized both for joining the different shelf tiers to two or more side walls, and for joining the corners. The shelving system will then preferably not have any protruding parts, in which case however the shelf tiers passing through the recesses will be visible in the outermost side walls of the shelving system.

According to a further aspect of the invention, a shelving system is built up as a framework with one column or two or more columns of shelf tiers, these having common side walls and a rear part being able to be inserted into at least one such column. To insert such a rear part, the side walls have longitudinal grooves along their rear long sides and the shelf tiers have through holes along their rear long sides. If a rear part is desired in several columns, these consist of separate boards, one for each column.

DESCRIPTION OF DRAWING The invention will be described in greater detail below, with reference to the figures, in which: Fig. 1 shows in perspective an outer side board (side wall) for a bookcase, which bookcase is arranged to be joined according to a preferred embodiment of the invention.

Fig. 2 shows in perspective an upper board for the bookcase in Figure 1, which upper board is adapted to be joined to the side board in Figure 1.

Fig. 3 shows in perspective, obliquely from behind, the same bookcase as in Figure 1 and 2 and how a shelf tier in the bookcase is to be fitted in.

Fig. 4 shows in perspective, obliquely from behind, the same bookcase as in Figure 1,2 and 3, how a rear part is to be fitted in and how the upper board in Figure 2 is to be fitted in.

Detail 1 in Figure 1 represents an outer side board 1 in a bookcase which is intended to be joined according to a preferred embodiment of the invention. The side board, which is termed a first board 1 below, is seen in the figures obliquely from behind of an conceived bookcase in which it constitutes the side wall. This first board 1 has in a first area 2 a recess 3, which recess is located right out at the short end of the first board 1. The recess 3 has a width 3b in the longitudinal direction of the first board, which width is adapted to receive the thickness of a second board, which is shown in Figure 2. The recess 3 has on its side wall a batten 4. Arranged in a second area 5 of said first board 1, on the inside of the first board, is a groove 6, which is situated close to the short end edge of the first board, parallel to the same. For aesthetic reasons, the groove 6 extends preferably not right up to the longitudinal side of the first board 1. This long side edge will form the front side edge in the assembled bookcase. Arranged on the opposing long side of the first board, i. e. the long side which lies in the same area as the recess, parallel to the long side and on the inside of the board is a longitudinal groove 7 for the insertion of a third board (shown in Figure 4), which will form the rear part in the bookcase.

In Figure 2,8 represents the second board, which is intended to be joined to the first board 1. Here a first area 10 of the second board 8 will be joined at right angles in the main to the first area 2 of the first board. A second area 9 of the second board 8 will be joined at right angles in the main to the first area 5 of the first board 1. The second board has, right out by the short end of the board, in the second area 9, a recess 13, which has a width in the longitudinal direction of the board which is adapted to receive the thickness of the first board 1. The first area 10 of the second board has on the underside a groove 12, which is intended to receive the batten 4 of the recess 3 in the first board 1. The groove 12 is situated close to the short end edge of the second board and parallel to the same. For aesthetic reasons, the groove 12 extends preferably not right up to the long side of the second board 8. This long side edge will be visible on the rear side of the assembled bookcase. Arranged by this long side, parallel to the same, on the underside, is a longitudinal groove 14 for insertion of the third board, which will form the rear part in the bookcase. The recess 13 has on its side wall a batten 11 which is adapted to be inserted into the groove 6 in the second area 5 of the first board 1. If the second board 8, instead of representing the topmost horizontal board in a bookcase, represents an intermediate shelf tier, then the longitudinal

groove 14 consists instead of a longitudinal, through hole 14, the third board being capable of being inserted completely through this hole.

Figure 3 shows a number of vertical boards 1 and horizontal boards 8, which are joined to form a bookcase, which is seen obliquely from behind, the rear part not yet having been fitted. In the example, a shelf tier 8 is also shown which has not yet been pushed into place from behind into the recesses 3 of the vertical walls. The grooves 6,7,12 and 14 or the battens 4 and 11 are not shown in Figure 3, but grooves 6 and 12 and battens 4 and 11 are arranged in a corresponding manner to that shown in Figure 1 and 2, preferably in all recesses 3 and in all second areas 5 of the vertical boards 1 and in all first areas 10 and in all recesses 13 of the horizontal boards 8. Grooves 7 and 14 (or holes 14) are preferably arranged on all vertical and horizontal long sides respectively which face the rear side of the bookcase, i. e. the side which is visible in the figure. The recesses 3,13 which are not placed right out at the short ends of the boards have two side walls, it being possible to provide one or both with battens. The corresponding areas 5,10 are then adapted for this with a groove on one side or two grooves, one lying on each side. It is also conceivable that the bookcase is sufficiently stable without battens and grooves having to be located in all recesses 3,13 and corresponding areas 5,10, especially if the bookcase is stabilized by a rear part. If the rear part is to be fitted, grooves for this are arranged on both sides of the vertical boards lying in between and through holes in the horizontal boards lying in between. Grooves 7 are only arranged on the inside of the outermost vertical boards, while in the outermost (upper and lower) horizontal boards grooves 14 are disposed which thus preferably do not go through.

Figure 4 shows a bookcase which is joined according to the invention and which is seen obliquely from behind. The grooves 6 and 12 or battens 4 and 11 are not shown in this figure either. The grooves 7 and grooves/holes 14 are indicated, however, in certain places.

The bookcase shown consists of three vertical shelf sections. In the middle one, a third board (a rear part) 15 has been placed in the grooves 7 and the grooves/holes 14. In the left- hand section a rear board 15 is about to be pushed into place. The bookcase can be provided with a rear board 15 in all sections, in no section or just in one or some sections.

The rear board 15 has the advantage when present of stabilizing the structure. An alternative to the embodiment shown in the figure is that a third board (rear board) is inserted horizontally along a shelf tier, the grooves 7 in the intermediate boards being

through holes instead and the grooves/holes 14 in all cases not being penetrating grooves. A structure is also conceivable in which the bookcase e. g. is to form a divider in a room, in which certain sections have a rear part on one side of the bookcase while other sections have a rear part on the other side of the bookcase. It is also conceivable for the rear boards to be inserted in an intermediate position, it being possible to use both sides of the bookcase.

When assembling a bookcase according to the figures, it is best to start out from a horizontal bottom board 8, into the recesses of which vertical boards 1 are inserted into place. Then all the upper horizontal boards except for the topmost are inserted into place in their recesses, following which the rear part 15 is inserted into desired sections. Finally, the entire structure is secured by inserting the topmost horizontal board into place.

The invention is not restricted to the embodiment shown, but can be varied within the scope of the claims. The skilled man easily perceives that the concept of the invention is applicable to other types of structures, such as e. g. containers, but also to other furniture such as sofas, e. g. for joining the back rest and arm rests etc. The joining does not have to be at right angles either, even if this is the most advantageous structure in manufacturing terms. Furthermore a shelving system, such as that shown in the figures, can be rotated 45° around an imaginary axis, which is at right angles to the rear part and be adapted to obtain a level base, which on a smaller scale gives e. g. a wine rack of a type known in itself. The shelf tiers in the figures can also be disposed to be pushed into place from the front, the grooves 7 and grooves/holes 14 also being adapted according to this. The skilled man also perceives easily that the recesses can instead be provided with grooves, while the corresponding areas are provided with battens. Nor is there anything in the structure preventing only the first area, for example, of the boards 1 and 8 being provided with grooves/battens, while the second area consists only of a smooth short end or a recess, if it proves to be the case that the structure is nevertheless sufficiently stable for certain application areas. Naturally, there is nothing to prevent the boards from being glued together in the joining areas, if the user does not wish to have the option of dismantling the structure. However, this is not in any way necessary for the stability of the structure.