GB2459477A

GB2459477A - Arrangement for applying and maintaining the tension of a load bearing fabric on an item of furniture

Info

Publication number: GB2459477A
Application number: GB0807419A
Authority: GB
Inventors: Ferenc Juhasz
Original assignee: Faversham Furniture Ltd
Current assignee: Faversham Furniture Ltd
Priority date: 2008-04-23
Filing date: 2008-04-23
Publication date: 2009-10-28
Also published as: GB2459477A8; GB0807419D0

Abstract

An arrangement 10 for tensioning and maintaining the tension of a load-bearing fabric 12 comprises two retaining members 26,28 which are arranged to pivotally engage opposing ends of a main supporting frame 14. The retaining members 26, 28 can be moved from an open position, as shown in Fig. 2, to a closed position in which they engage one another, as shown in Fig.4B. As the retaining members move to the closed position they trap the peripheral rim 16 of the fabric and stretch the fabric in opposite directions so that it becomes tensioned. Securing means, e.g. screw 48, may be provided for securing the retaining members 26, 28 in the closed position. The tensioning apparatus may be used with any fabric suitable for use with furniture. In an embodiment, the fabric is woven PVC-coated polyester and the main supporting frame 14 forms part of a seat portion or a seat back of a chair or stool.

Description

I

Support for Load-bearing Fabric This invention relates to a support for a load-bearing fabric and, in particular, to a support for tensioning, and maintaining the tension of, a load-bearing fabric.

High-tension fabrics for use in furniture and, in particular, for use in seating products are well-known in the art. GB 1486142 (Stumpf) and US 6899398 (Coffield) both disclose the use of a fabric held in a state of high tension, in order to support the weight of a person sitting on the fabric and, at the same time, allowing a slight deflection, or stretching, of the fabric for increased comfort. Once the user of a chair incorporating such a fabric stands up and removes weight from the fabric, the tension of the fabriccaused by the apparatus is enough to return the fabric to its previous tense state without any visible residual slackness or stretching.

In both of the cases mentioned above, specialist machinery and/or equipment is required to attach the fabric in a state of high tension to the frame in such a manner that the fabric is held taut in all directions.

In other examples, the tensioning of the fabric is achieved during a final assembly stage, through the use of a plurality of bolts which, when progressively tightened, pull the fabric to the required tension. This often results in an undesirable amount of visible hardware, particularly when the furniture is viewed from the rear. Cases of this type typically conform to a rectangular fabric shape due to the difficulty in tensioning the fabric using the bolts in anything other than a straight line.

An aim of the present invention is to provide an improved apparatus for tensioning, and maintaining the tension of, a portion of load-bearing fabric, whereby the apparatus can be operated by hand, and without the use of specialist equipment.

In one aspect of the present invention, an apparatus for tensioning, and maintaining the tension of, a load-bearing fabric, comprises a supporting frame having a first end and a second end opposite to the first end, a first retaining member and a second retaining member, the first retaining member being arranged pivotally to engage the first end of the supporting frame, and the second retaining member being arranged pivotally to engage the second end of the supporting frame, the first and second retaining members being arranged such that, in a closed position, the retaining members engage one another, causing the load-bearing fabric to be tensioned; and securing means for securing the retaining members in said closed position.

Preferably, in the closed position, the first and second retaining members engage the load-bearing fabric and, more preferably, the first and second retaining members urge opposite edges of the load-bearing fabric in opposite directions.

The supporting frame may further include a first side and a second side opposite the first side and, preferably, the first and second retaining members each includes at least one arm.

Advantageously, in the closed position, the arms of the first and second retaining members engage the load-bearing fabric and, more advantageously, the arms of the first and second retaining members urge the load-bearing fabric in a direction substantially perpendicular to the plane of the fabric.

The load bearing fabric may include a fabric rim. The fabric rim may be of substantially greater thickness than the rest of the load-bearing fabric. Preferably, the fabric rim has a perimeter greater than an inner perimeter of the supporting frame.

Advantageously, the fabric rim is at least partially encapsulated between the supporting frame and the first and second retaining members. The fabric rim may be formed by sewing or adhering an object into the fabric. The object may be an aluminium rod.

The securing means may be a screw-threaded member, a bolt, a pin, a rivet or adhesive.

In another aspect of the present invention, a piece of furniture includes an apparatus, the apparatus being as defined above.

In yet another aspect of the present invention, a method of tensioning, and maintaining the tension of, a load-bearing fabric, comprises the steps of providing an apparatus having a supporting frame, a first retaining member and a second retaining member, the supporting frame having a first side, a second side, a first end and a second end, the first retaining member being arranged pivotally to engage the first end of the supporting frame, and the second retaining member being arranged pivotally to engage the second end of the supporting frame, the first and second retaining members being arranged such that, in a closed position, the retaining members engage one another, causing the load-bearing fabric to be tensioned; and securing the first and second retaining members with a securing means.

In yet another aspect of the present invention, a load-bearing fabric is in a state of tension, the tension being achieved by the method defined above.

An advantage of the present invention is that it allows fabrics of non-rectangular (even round or oval) shapes to be tensioned using the same apparatus as for a rectangular fabric.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which: Figure 1 is an exploded view of components of a chair to be constructed in accordance with a first embodiment of the present invention; Figure 2 is a perspective view of a portion of a chair constructed in accordance with the first embodiment of the invention; Figure 3 is a detailed sectional view of one end of the portion of the chair shown in Figure 2; S 4 Figure 4A is a sectional view of the chair portion shown in Figure 2, during a first stage of construction; Figure 4B is a sectional view of the chair portion shown in Figure 2, during a second stage of construction; Figure 5A is a sectional view of one side of the chair portion shown in Figure 2, during a first stage of construction; Figure 5B is a sectional view of one side of the chair portion shown in Figure 2, during a second stage of construction; Figure 5C is a sectional view of one side of the chair portion shown in Figure 2, during a third stage of construction; Figure 6 is a detailed sectional view of one side of the chair portion shown in Figure 2; Figure 7 is an exploded view of components of a chair, having a curved seat back, to be constructed in accordance with a second embodiment of the invention; and Figure 8 is an exploded view of components of a chair to be constructed in accordance with a third embodiment of the invention.

Referring to the drawings, Figure 1 shows a first embodiment of a support structure 10 for supporting a panel of load-bearing fabric 12. The load-bearing fabric 12 can be any fabric suitable for use with furniture. In this case, the fabric is woven polyvinyl chloride-coated (PVC-coated) polyester. The support structure 10 includes a supporting frame 14 which frames the panel of load-bearing fabric 12. The supporting frame 14 might constitute, for example, a seat-back of a chair or a seat portion of a chair or stool. In this embodiment, the supporting frame 14 constitutes a seat-back portion of a chair.

The panel of load-bearing fabric 12 includes a fabric rim 16 formed around its perimeter, the rim being of substantially greater thickness than the rest of the panel.

The fabric rim 16 can be formed by any one of many known methods. In this case, for example, a length of tubing is sewn into the rim of the load-bearing fabric 12 to form the fabric rim 16. Alternatively, the fabric rim 16 may be formed from a length of any other material, for example, aluminium, attached to the fabric 12. As an alternative to sewing, the tubing may be attached to the fabric 12 using adhesive.

The supporting frame 14 includes a first side member 18, a second side member 20, an upper member 22 and a lower member 24. Each of the members 18, 20, 22, 24 of the supporting frame 14 is formed such that, in cross-section, it resembles an elongate L-shaped piece. The supporting frame 14 formed by the L-shaped members 18, 20, 22 and 24 can receive the panel of load-bearing fabric 12, such that the fabric will be loose and un-tensioned, when the fabric rim 16 rests against the members of the supporting frame.

The support structure 10 further comprises a first retaining member 26 and a second retaining member 28, each of which is shaped substantially the same as opposite halves of the supporting frame 14. Each retaining member 26, 28 is slightly smaller than the respective complementary part of the supporting frame 14. Furthermore, each retaining member 26, 28 fits within the perimeter of one half of the supporting frame 14. Each retaining member 26, 28 comprises a base 26a, 28a, and two arms 26b, 28b. Respective first and second apertures 30, 32 are formed at the end of each of the arms 26b, 28b of each of the retaining members 26, 28. A third aperture 34 is formed in the upper member 22 of the supporting frame 14, and a fourth aperture 36 is formed in the lower member. 24 of the supporting frame. When the arms 26a, 28a and 26b, 28b of the first and second retaining members 26, 28 are brought together, the apertures 30, 32 come into alignment with the third aperture 34 and the fourth aperture 36 respectively, for receipt of a retaining screw (see Figure 4B).

In use, the panel of load-bearing fabric 12, having a fabric rim 16 formed around the perimeter thereof, is positioned on the supporting frame 14 of the chair to which the load-bearing fabric is to be attached. In its natural state, the panel of load-bearing fabric 12 is un-tensioned, and rests on the supporting frame 14. The first retaining member 26 is then positioned with its base 26a in engagement with the first side member 18 of the supporting frame 14, as shown in Figure 2. Figure 3 shows, in more detail, a cross-sectional schematic view of the encircled region of Figure 2. The first retaining member base 26a is shaped such that, when positioned to engage the first side member 18 of the supporting frame 14, the fabric rim 16 of the panel of load-bearing fabric 12 is encapsulated, and prevented from falling away from the supporting frame 14.

Once the first retaining member 26 is positioned, the second retaining member 28 can be positioned within the supporting frame 14, such that the base 28a of the second retaining member 28 engages with the second side member 20 of the supporting frame 14, encapsulating the fabric rim 16 of the panel of load-bearing fabric 12 that rests on the supporting frame.

Referring now to Figure 4A, which shows a cross-sectional view of the apparatus in use, it can be seen that, with both the first retaining member 26 and the second retaining member 28 in position, the ends of each of the retaining member arms 26b, 28b are lowered, with the retaining member bases 26a, 28a pivoting on the first and second side members 18, 20 of the supporting frame 14 respectively. The combined length of the arms of the first and second retaining members 26B, 28B is slightly greater than the lengths of the upper and lower members 22, 24 of the supporting frame 14, such that, when lowered, the arms engage one another, therefore urging the first retaining member base 26a in a direction denoted by the arrow A, and the second retaining member base 28a in a direction denoted by the arrow B. Referring, once again, to Figure 3, it can be seen that, when the arm 26b of the first retaining member 26 is lowered towards the supporting frame 14, an engagement end 38 of the retaining member base 26a moves in a direction denoted by the arrow C, and engages with a receiving end 40 of the side member 18 of the supporting frame 14.

As the engagement end 38 moves further in the direction of the arrow C, the load-bearing fabric 12 becomes trapped between the engagement end and the receiving end 40. At the same time, the second retaining member base 28a (not shown in Figure 3) is engaging with the second side member 20 (not shown in Figure 3) of the supporting frame 14, causing the same effect to occur on the load-bearing fabric 12 at that end of the supporting frame. The resulting effect of the load-bearing fabric 12 being urged in opposite directions is that tension is created in the fabric, the maximum tension occurring when the arms 26b, 28b of the retaining members 26, 28 engage fully with the upper and lower members of the supporting frame 22, 24.

Figures 5a to 5c each shows a cross-sectional view through the supporting frame 14 in a direction perpendicular to the view shown in Figures 4a and 4b. Figure 5a shows the panel of load bearing fabric 12 in an untensioned state, with the fabric rim 16 resting on the upper and lower members 22, 24 of the supporting frame 14. The retaining member arms 26b, 28b are shown to be in open positions, similar to the positions of the arms shown in Figure 2. In Figure Sb, the retaining member arms 26b, 28b are nearer to the upper and lower members 22, 24 of the supporting frame 14, as a result of the retaining members 26, 28 being pivoted about the retaining member bases 26a, 28a. As the retaining member arms 26b, 28b are lowered, the fabric rim 16 is encapsulated between the arms and the upper and lower members 22, 24 of the supporting frame 14. As the arms 26b, 28b are lowered further still, an inner portion 42, 44 of each of the retaining member arms 26b, 28b engages with the panel of load bearing fabric 12, urging it downwards.

Figure 6 shows, in more detail, the inner portion of the arm 42, 44 engaging with the portion of load bearing fabric 12, urging the fabric in a direction denoted by the arrow D. When the arms 26b, 28b have been lowered as far as possible, such that they engage, and partially compress, the fabric rim 16, then the resultant effect of the inner portions of the arms 42,44 moving down beyond end points 46 of the upper and lower members 22, 24, is the tensioning of the panel of load bearing fabric 12 in a direction perpendicular to the tensioning shown in Figure 4b. The resulting fabric, in a state of tension, is shown in Figure 5c.

Referring, again to Figure 4b, once the arms 26b, 28b have been manoeuvred into a closed position, and the load bearing fabric 12 is in a state of tension in directions parallel to both the upper and lower members 22, 24 and the first and second side members 18, 20 of the supporting frame 14, a securing means 48, such as a threaded screw, can be inserted through the first aperture 30, and into the third aperture 34, to secure the retaining members 26, 28 in place. Similarly, a second securing means, such as a screw, can be inserted through the second aperture 32, and into the fourth aperture 36, securing the retaining members 26, 28 in place.

Figure 7 shows a modified version of the support structure 10 of Figure 1. Like reference numerals are used for like parts, and only the modifications will be described. The modifications concerned are that all the sides 18, 20, 22, 24 are curved.

Figure 8 also shows a modified version of the support structure 10 of Figure 1. Again, like reference numerals are used for like parts, and only the modifications will be described. In this embodiment, the first and second retaining members 26, 28 attach to the upper and lower members 22, 24 of the supporting frame 14. In a closed position, the apertures 30, 32 formed by the retaining member arms 26b, 28b align with the apertures 34, 36 formed in the first and second side members 18, 20 of the supporting frame 14. Essentially, the seat back shown in Figure 8 is similar to the seat back shown in Figure 1, rotated about 1.571 radius (90 degrees).

It will be apparent that an advantage of the present invention is that only two unobtrusive securing means are used and, therefore, a piece of furniture which includes the apparatus as hereinbefore described will not suffer from the problem of having an undesirable amount of visible hardware, as the prior art does. Furthermore, this invention has the advantage that specialist machinery or equipment is not required to tension the fabric.

It will be appreciated by a person skilled in the art that various modifications to the support structure described hereinbefore can be made without departing from the scope of the appended claims.

Claims

Claims 1. An apparatus for tensioning, and maintaining the tension of, a load-bearing fabric, the apparatus comprising: a supporting frame having a first end and a second end opposite to the first end; a first retaining member and a second retaining member, the first retaining member being arranged pivotally to engage the first end of the supporting frame, and the second retaining member being arranged pivotally to engage the second end of the supporting frame; the first and second retaining members being arranged such that, in a closed position, the retaining members engage one another, causing the load-bearing fabric to be tensioned; and securing means for securing the retaining members in said closed position.
2. An apparatus according to claim 1, wherein, in the closed position, the first and second retaining members engage the load-bearing fabric.
3. An apparatus according to claim I or claim 2, wherein, in the closed position, the first and second retaining members urge opposite edges of the load-bearing fabric in opposite directions.
4. An apparatus according to any one of the preceding claims, wherein the supporting frame further includes a first side and a second side opposite the first side.
5. An apparatus according to any one of the preceding claims, wherein the first and second retaining members each includes at least one arm.
6. An apparatus according to claim 5 when appended to claim 4, wherein, in the closed position, the arms of the first and second retaining members engage the load-bearing fabric.
7. An apparatus according to claim 6, wherein, in the closed position, the arms of the first and second retaining members urge the load-bearing fabric in a direction substantially perpendicular to the plane of the fabric.
8. An apparatus according to any one of the preceding claims, wherein the load-bearing fabric includes a fabric rim.
9. An apparatus according to claim 8, wherein the fabric rim is of substantially greater thickness than the rest of the load-bearing fabric.
10. An apparatus according to claim 8 or claim 9, wherein the fabric rim has a perimeter greater than an inner perimeter of the supporting frame.
1. An apparatus according to any one of claims 8 to 10, wherein the fabric rim is at least partially encapsulated between the supporting frame and the first and second retaining members.
12. An apparatus according to any one of claims 8 to 11, wherein the fabric rim is formed by sewing an object into the fabric.
13. An apparatus according to any one of claims 8 to 11, wherein the fabric rim is formed by adhering an object into the fabric.
14. An apparatus as according to claim 12 or claim 13, wherein the object is an aluminium rod.
15. An apparatus according to any one of the preceding claims, wherein the securing means is a screw-threaded member.
16. An apparatus according to any one of claims I to 14, wherein the securing means is a bolt.
17. An apparatus according to any one of claims I to 14, wherein the securing means is a pin.
18. An apparatus according to any one of claims 1 to 14, wherein the securing means is a rivet.
19. An apparatus according to any one of claims I to 14, wherein the securing means is adhesive.
20. A piece of furniture including an apparatus according to any one of claims I to 19.
21. A method of tensioning, and maintaining the tension of, a load-bearing fabric, the method comprising the steps of: providing an apparatus having a supporting frame, a first retaining member and a second retaining member, the supporting frame having a first side, a second side, a first end and a second end, the first retaining member being arranged pivotally to engage the first end of the supporting frame, and the second retaining member being arranged pivotally to engage the second end of the supporting frame, the first and second retaining members being arranged such that, in a closed position, the retaining members engage one another, causing the load-bearing fabric to be tensioned; and securing the first and second retaining members with a securing means.
22. A load-bearing fabric, in a state of tension, the tension being achieved by the method of claim 21.
23. An apparatus substantially as hereinbefore described, with reference to, and as illustrated by, the drawings.
24. A method substantially as hereinbefore described, with reference to, and as illustrated by, the drawings.