Piece of furniture to sit on

The present invention concerns a piece of furniture to sit on, in particular of the type comprising a frame, having at least one bearing face formed of a supple element that is stretched by means of clamping means.

By a piece of furniture to sit on is understood in the first place a chair, in particular a garden chair or armchair, but in general, according to the invention, every piece of furniture upon which persons can take place, i.e. also a sofa or a bed, must be understood by it.

By the bearing face Is meant the seat, the place to lie down on respectively in the case of a bed, or the back support of the piece of furniture to sit on.

The aforesaid supple element may be formed of any supple material whatsoever, for example a fabric, a gauzy layer, a fall, leather, a plaited structure, etc.

It is known that In the case of sitting furniture whose seat and/or back support consists of a supple element, this element can be stretched In different manners.

According to a first possibility, use can be made of draw springs provided between the frame of the piece of furniture to sit on and the edge of the supple element, such that a tensile force is exerted on the supple element, as a result of which it will be stretched. A disadvantage of this technique consists in that such springs are usually visible, that one can hurt oneself on these springs, and than the springe give away while the piece of furniture is in use, creating a stretch effect that is little stable.

It is also known to stretch such a supple element in a fixed frame by means of auxiliary tools. A disadvantage of this technique consists in that special auxiliary tools are required. Moreover, this fixing technique requires a sound professional knowledge.

The present invention aims a piece of furniture to sit on of the above-mentioned type which does not have the aforesaid disadvantages.

To this aim, this piece of furniture to sit on is characterised in that the clamping means at least consist of two parts on the one hand, a first part assuming a specific position in relation to the bearing faces of the frame of the piece of furniture to sit on and a second part onto which the above-mentioned supple element is fixed respectively, the two parts being mainly situated in two planes situated one after the other, seen in the direction which is perpendicular to the bearing face, and means which make it possible to move the second part in relation to the first part on the other hand, especially to move it systematically, in particular up to a specific end position, such that a stretch effect is created in the supple elements by realising said movement, said means consisting of connecting elements formed of one or several screws which provide for the above-mentioned movement when being screwed on.

By making use of the clamping means provided on the piece of furniture to sit on which allow for a systematic movement of the second part, a sound clamping force can be obtained in a relatively simple manner. As will further become clear from the description, such clamping means can also be realised in a rather single manner, such that no expert knowledge is required to realise a tension by means of these clamping means, and no special tools are required therefor.

The above-mentioned two parts are mainly situated in two planes situated one after the other, seen in the direction which is perpendicular to the bearing face. This offers the advantage that in the stretched condition, the first part is situated behind the actual bearing face, so that it does not form an interfering factor.

In a preferred embodiment, the above-menitioned means for the mutual movement of the two parts consist of connecting elements that can be clamped with which said two parts can be moved towards one another, while the different co-operating parts, in other words the above-mentioned two parts and the connecting elements that can be clamped, are designed such that the second part, when the connecting elements are tightened, thanks to the co-operation between the different parts, is forced to move, which leads to the supple element being stretched.

According to the most preferred embodiment, the above-mentioned two parts are moreover fixed to one another by means of the connecting elements. This offers the advantage that the two parts are situated entirety behind one another. This makes it possible to realise constructions whereby the width of the bearing face Is not influenced in a disadvantageous manner by the presence of the clamping means. As the connecting means hereby consist of one or several screws which provide for the above-mentioned movement when being screwed on, a positive movement of the second part In relation to the first part, up to a specific position, can be easily realised, simply by screwing on the above-mentioned screws.

According to a very practical embodiment, one of the above-mentfoned two parts is provided with screw holders for the above-mentioned screws, and the other part is provided with passages for the screws which are formed such that said screws can tilt and/or shift In them, such that by tightening the screws, they will be adjusted, which has for a result that the second part is moved and the supple element is stretched.

According to a particularly preferred aspect of the invention, the clamping means, in particular the first part and the second part, are made of metal, while the frame of the piece of furniture to sit on is mainly made of wood. The metal parts allow for the supple element to be well stretched, while the advantages of wooden chairs are nevertheless maintained.

The supple element is preferably stretched in a frame of its own which absorbs the clamping forces, as well as the tension when a pressure is exerted on the bearing face, whereby this frame as such is provided to the frame of the piece of furniture to sit on. Thus, no tensile forces are transferred to the frame of the piece of furniture itself, so that it is less loaded and so that also constructions in other shapes become possible than those that were known until now.

It is clear that the use of such a separate frame to absorb the clamping forces, in particular a frame made of metal, combined with a wooden frame, also offers different advantages, irrespective in what manner the supple element is stretched in the frame. Such a metal frame makes sure that large clamping forces can be realised, without creating an extra load for the wooden frame of the piece of furniture, which is usually less rigid.

Independent of the preceding characteristics, the invention also concerns a piece of furniture to sit on, of the type comprising a frame, having at least one bearing face formed of a stretched, supple element, characterised in that the supple element is stretched in a frame of its own which absorbs the clamping forces, as well as the tension when a pressure is exerted on the bearing face, and in that this frame is mainly made of metal, while the actual frame of the piece of furniture to sit on is mainly made of wood.

It is clear that the invention also concerns an element to form a bearing face, in other words a frame, preferably made of metal, in which a stretched, supple element is provided by means of the above-mentioned clamping means. For, such an element can be sold as separate to be installed in pieces of furniture to sit on.

In order to better explain the characteristics of the invention, the following preferred embodiments are described as an example only without being limitative in any way, with reference to the accompanying drawings, in which:

• figure 1 represents a view in perspective of a piece of furniture to sit on according to the invention;
• figure 2 represents the piece of furniture to sit on when disassembled;
• figure 3 represents a section according to line III-III in figure 2 to a larger scale;
• figures 4 to 7 represent views analogous to that of figure 3, but In different steps while the supple element Is being stretched and the whole is being mounted to the frame of the piece of furniture to sit on;
• figure 8 represents a section according to line VI-II-VIII in figure 1;
• figure 9 represents the part indicated by F9 in figure 8 to a larger scale.

As represented in the figures, the invention concerns a piece of furniture 1 to sit on, in this case a chair, of the type comprising a frame 2, having one or several bearing faces, in this case a seat 3 and a back support 4, formed of a supple element 8 which is stretched by means of clamping means 5, in this case a fabric or the like.

As is shown in more detail in figures 2 to 9, the above-mentioned clamping means 5 at least consist of two parts, a first part 7 which assumes a specific position in relation to the frame 2 of the piece of furniture 1 when mounted, and a second part 8 respectively to which the above-mentioned supple element 8 is fixed on the one hand, and of means 9 which make it possible to move the second part 8 in relation to the first part 7 on the other hand, especially to move it systematically, in particular up to a specific end position, such that a stretch effect is created in the supple element 6 by realising said movement.

Both as far as the seat 3 and the back support 4 are concerned, the supple element 6 is exclusively fixed to the left and right side of the piece of furniture 1 to sit on. On either side are provided clamping means 5, as mentioned above. These clamping means 5, in particular the parts 7 and 8 and the means 9, are described in more detail hereafter by means of the sections of figures 3 to 7, which are related to the seat 3.

The parts 7 land 8 are each mainly formed of a lath. The part 7 situated on the left side is connected to the part 7 situated on the right side via cross connections 10, such that the whole formed of the two parts 7 and the cross connections 10 In between forms a separate frame 11.

The above-mentioned means 9 to move the parts 8 In relation to the parts 7, at least while the supple element 8 is being stretched, consist of connection elements that can be clamped, formed of screws 12, with which the two parts 7-8 can be moved towards one another and in this case can also be fixed on top of one another.

In every first part 7 are provided passages 13 for the screws 12 which are made such that said screws 12 can be tilted in them and/or be laterally shifted in them.

In order to obtain that the screws 12 can be tilted and/or be shifted in the passages 13, these passages 13 and screws 12 have different particular technical design characteristics:

• as is for example shown in figure 3, the passages 13 are widened at least in certain directions, such that the screws 12 have the possibility to carry out a tilting movement in the passages 13. In the given example, this widening consists in that a conical recess 14 is formed on the passage 13 on the side of the first part 7 directed to the second part 8.
• The passages 13 have a diameter D1, in the direction in which the screws 12 must be able to shift, which is significantly larger than the diameter D2 of the screws 12, so that the screws cannot only shift sideways, but can also be tilted in the accompanying passages 13.
• The screws 12 are provided with conical heads 15 which can work in conjunction with conical seats 16 at the passages 13, such that the screwa-12 are forced to move laterally when being screwed on as a result of this co-operation.

It is clear that, according to variants, more or less of the above-mentioned design characteristics and/or other design characteristics can be applied. It is important that it remains possible for the screws 12 to shift laterally and/or to tilt in the passages 13.

In each of the second parts 8 are provided screw holders 17 for the screws 12 at mutual distances, in other words openings with Internal screw thread.

The supple element 8 is fixed to the left, right side respectively, to the respective second part 8, as it is provided around it like a loop, as indicated with reference 18.

The screw holders 17 and the passages 13 are provided such that every second part 8 can be fixed on the accompanying first part 7.

The clamping means 5, in particular the parts 7 and 8, as well as the cross connections 10 between the parts 7, preferably consist of metal, while the frame 2 of the piece of furniture 1 to sit on is made of wood.

The working of the clamping means 5 is represented step by step in figures 3 to 7.

First, the supple element 8 is provided over the lath-shaped parts 8, as shown in the top part of figure 3.

Then, one of the parts 8 is connected to the accompanying first part 7 by means of screws 12, as represented in the right part of figure 4, whereby the screws 12 concerned are not entirely tightened yet. It should be noted that an opening is provided in the supple element 6 at the height of every screw holder 17, so that the screws 12 concerned fit in it, which opening can possibly also be formed automatically by pushing the screw 12 concerned through the supple element 8.

Subsequently, a connection is also made on the opposite side, on the left in figure 5, between the first part 7 and the second part 8, by means of screws 12. As is shown in figure 5, the special design of the passages 13 and the screws 12 enables the second part 8 to initially assume a shifted and/or tilted position in relation to its end position.

By then screwing on the screws 12 on the left side, a situation as in figure 8 is first obtained, whereby the second part 8 is forced to move in a parallel manner to the first part 7, whereby a certain tension is already created.

By then tightening the screws 12 further, both on the right and on the left side, a further lateral movement L is brought about, as a result of which a greater stretch effect is created.

It is clear that the dimensions of the supple element 8 are selected such that, between the situation in figure 3 and that of figure 7, the material of the supple element 8 is being stretched.

Finally, the frame 11 is fixed in the frame 2 together with the stretched element 8 by means of screws 19, as represented In figures 8 and 9, or in another manner.

As is clear from figure 2, the back support 4 Is built analogous to the seat 3.

As the supple element als stretched in a frame 11 of its own in the given embodiment, which is preferably made of metal, it is clear that the actual frame 2 of the piece of furniture 1 to sit on is guarded from tensile forces caused by the stretching of the supple element 6. This allows, for example, to make the back support 4 of the piece of furniture 11 to sit on, in particular the parts of the frame 2 belonging to It, less heavy, and no extra connection must be provided between the wooden lateral parts 20 of the back support, as is clearly shown in figure 2.

As Is shown in figures 1,2,8 and 9, the parts 7-8, in particular the laths of which they are formed, may be slightly bent, or they may have a buckle 21 on one or several of their far ends, in this case at the height of the front side of the seat 3, so as to obtain a more comfortable seat 3.

The present invention is by no means limited to the above-described embodiments represented In the accompanying drawings; on the contrary, such a piece of furniture to sit on can be made in all sorts of shapes and dimensions while still remaining within the scope of the invention.

Thus, the supple element 8 must not necessarily be provided like a loop, for example, around every second part 8. Any form of fastening can be applied to this end. Hence, according to a special embodiment, the parts 8 may for example consist of metal eyes provided in the supple element 8, whereby the supple element 8 is then slid for example over the screws 12 by means of said eyes, for example between the first parts 7 made in the shape of laths on the one hand, and a second lath situated on top of it on the other hand.