WO2017137614A1

WO2017137614A1 - Chair with flexible lumbar support

Info

Publication number: WO2017137614A1
Application number: PCT/EP2017/053087
Authority: WO
Inventors: Alexandre Guichard
Original assignee: Revology Sa
Priority date: 2016-02-10
Filing date: 2017-02-10
Publication date: 2017-08-17
Also published as: EP3273825A1; FR3047394A1; JP2019504748A; EP3273825B1; US20210186218A1; ES2698204T3; FR3047394B1

Abstract

The invention concerns a chair comprising: a. a tubular base (121, 122, 123, 124); b. a seat portion (110) attached to said base, said seat portion and said base constituting the seat; c. a tubular arch (130) made from a single part constituting the backrest and linked to two of the legs (123, 124) of the base; d. a resilient dorsolumbar support (140), comprising two ends, one of which is free and the other is attached to the seat.

Description

FLEXIBLE LUMBAR SUPPORT CHAIR

The invention relates to a chair with flexible lumbar support. The invention more particularly relates to a chair with fixed structure, non-folding backrest, lightweight, but providing effective lumbar support and adaptive to the user.

According to the prior art, a fixed structure chair is for example made of wood and has a backrest. According to an exemplary embodiment, the backrest comprises two amounts generally coming in extension of the rear legs, which amounts are linked by sleepers. The sleepers thus provide 3 main functions:

- a mechanical function of rigidity of the backrest and the chair as a whole;

a function of supporting the back of the user when he is seated on the chair;

- A gripping function, allowing to grab the chair by the folder to, inter alia, move it.

These rigid crosspieces do not allow to obtain an effective and adaptive back support in relation to the morphology of the user. But an effective back support is an element of essential comfort of a chair. To this end, according to the prior art, the back of the chair is furnished with a lumbar support cushion installed between the uprights. Other constructions of the file, especially in the field of office chairs, also provide an adaptive and efficient lumbar support. All these solutions of the prior art have the disadvantage of weighing down the chair, both in terms of weight and in aesthetic terms.

The invention aims to solve the disadvantages of the prior art and for this purpose concerns a chair comprising:

at. a tubular base;

b. a seat fixed to said base, said seat and said base forming the seat;

vs. a tubular arch constituting the backrest and linked to two of the legs of the base; d. a resilient thoracolumbar support comprising two ends of which one is free and the other is linked to the seat; and wherein the base and the tubular arch are made of a composite material with fiber reinforcement, comprising a natural fiber, in particular a plant fiber

Thus, the tubular arch of the backrest provides the functions of rigidity and grip, while the backrest support, which is not related to this arch, provides sufficient elasticity, and a "spring effect", allowing it to adapt to the user's morphology while providing effective support. The constitution of composite material gives, in particular to the chair rigidity and strength sufficient to avoid the use of sleepers as used on a wooden chair of the prior art, and thus allow the appropriate elastic movement of the backrest support for get that support. The use of one of a reinforcement fiber of natural origin allows a realization of the chair according to a principle of sustainable development, especially in terms of carbon footprint and extraction of natural resources, at least as advantageous as that of a wooden chair, while giving the chair lightness properties comparable to or even superior to those of wood or a metal structure.

The invention is advantageously implemented according to the embodiments and variants described below, which are to be considered individually or in any technically operative combination.

Advantageously, the connection of the thoracolumbar support to the seat is a removable connection. Thus, the chair is adaptable, by the use of different lumbar supports, in terms of firmness and aesthetics.

Advantageously, the tubular section of the arch is scalable between its connections to both feet. Thus the hoop is optimized in terms of strength, weight and rigidity depending on the composite material used. In the same way, the tubular section of the legs of the base is scalable between their end intended to rest on the ground and their connection to the seat.

Advantageously, the seat is made of a plastic material. This embodiment makes it possible at the same time to reduce the weight of the chair to make it adapt ci to external use and to allow economical assembly and manufacturing methods.

According to another embodiment, the seat is made of a metallic material. This embodiment allows to give the chair a style, called "bistro".

Advantageously, the seat comprises a connecting ring with the base and a portion, said seat cushion, assembled with said crown. This embodiment allows to customize the seat cushion, and in particular to use for the realization thereof a different material, color or finish from those of the crown.

According to alternative embodiments, the thoracolumbar support is also made of a plastic material reinforced or not by fibers. Thus, depending on the nature of the constituent material, said back support is more or less flexible, to adapt to the maintenance sought by the user and corresponds to different aesthetics of the chair object of the invention.

The invention also relates to a pre-assembled assembly, or kit, comprising a chair whose connection of the thoracolumbar support to the seat is removable and several thoracolumbar supports. Thus said chair is adaptable in terms of firmness of maintenance and aesthetics.

The invention also relates to a preconstituted assembly, or kit, comprising a chair and several seat cushions. This embodiment alone or in combination with the previous one allows the end user to customize the chair.

The invention is explained below according to its preferred embodiments, in no way limiting, and with reference to FIGS. 1 and 2, in which:

- Figure 1 shows in a front view of an embodiment of the chair object of the invention;

- Figure 2 shows a partial left view, the chair of Figure 1;

- And Figure 3 is a partial front view of an embodiment of the chair object of the invention comprising a hoop in two parts, a detail view shows an example of assembly of the two parts of the hoop.

FIG. 1, according to an exemplary embodiment, the chair which is the subject of the invention comprises a seat (1 10) constituted preferentially in a single piece of a plastic material. For example the plastic material constituting said seat is a bio-based polymer such as polyethylene, polyamide, cellulose acetate or polymethyl methacrylate, such biobased products are for example distributed by Arkema ^® group, 420 rue d'Estienne d'Orves, 92705 Colombes France, other suppliers offering similar products. According to a particular embodiment, the material constituting said seat consists of a matrix of a first biosourced polymer reinforced with fibers of a second biobased polymer whose melting temperature is higher than that of the first polymer. Said seat is advantageously made of a single molded part, and thus contributes to the rigidity of the chair. According to a particular embodiment, the seat (1 10) is substantially bowl-shaped and comprises a rigid crown frame (11 1) and a slightly curved portion (112) acting as a seat cushion, more flexible. According to an alternative embodiment, the seat of the chair object of the invention is made of a light metal material, injection moldable, for example a magnesium alloy.

According to a particular embodiment, the crown (1 1 1) and the seat cushion (1 12) are two separate parts assembled by clipping, bolting or gluing. This embodiment allows to customize the chair while streamlining production by keeping the maximum number of common parts to different models. As non-limiting examples, the ring is made of a plastic material and the seat cushion is made of a metallic material, the ring is made of a metallic material and the seat cushion is a caning in plastic or natural fibers.

According to an exemplary embodiment, the chair object of the invention comprises a base comprising 4 feet (121, 122, 123, 124). Alternatively the base includes 3 feet. Said feet are tubes preferably constituted of a composite material with fibrous reinforcement. Thus, the feet are rigid and light. Preferably, the composite material constituting said feet (121, 122, 123, 124) comprises a biosourced polymer matrix, for example a polyamide, in particular PA11, or a polyethylene, reinforced with continuous fibers, totally or partially of vegetable origin. By way of non-limiting example, said plant fibers are flax fibers, jute fibers, hemp, sisal fiber or bamboo fiber. The feet are assembled to the seat thus constituting the seat of the chair object of the invention. Advantageously, the material constituting the feet and the material constituting the seat are chosen so that they can be easily assembled by welding, for example by selecting thermoplastic polymer matrices, or by heat-sealing. This embodiment allows a very clean style and is used preferentially when the seat is made of a transparent material.

Alternatively or in a complementary manner, the assembly of the feet with the seat is made by a mechanical assembly, for example by fitting the feet into the sleeves made during the molding of the seat. In this case, the seat comprises a face of appearance, smooth, outside the bowl shape, and a technical face, inside the bowl shape, comprising arrangements adapted to the assembly or ribs. According to this embodiment the seat is made by implementing an injection molding process using dynamic heating of the mold by induction, as described in document EP 2 861 399.

The chair object of the invention comprises a hoop (130) tubular, constituting the back of said chair, and connected to the two feet (123, 124) of the base. According to alternative embodiments, the connection of the hoop to the feet (123, 124) is achieved by integrating the whole hoop and feet in one piece, in this case the seat comprises appropriate means for making the connection with this room. According to another variant, the connection of the hoop (130) with the feet (123, 124) is formed by molded sleeves with the seat, so that the seat, the base and the hoop constitute, after assembly, a rigid assembly, without any crossbar is necessary.

Said interlocking assembly is, according to one embodiment, completed by a gluing or welding, depending on the nature of the materials in the presence. Thus, the structure of the chair object of the invention is easily assembled without tools, which also facilitates its storage and delivery especially in the context of a mail order. The hoop (130) tubular is made of a composite material similar to that used for the realization of the base. Advantageously, the fiber content and the nature of the fibers or fiber mixture reinforcements used in the feet and the hoop differ, in order to achieve the mechanical properties appropriate to the functions of these components or for aesthetic reasons. Indeed, the use of reinforcing fibers of plant origin gives the base and the arch a particular aesthetic appearance without the need to paint them.

According to this exemplary embodiment, the thoracolumbar support (140) extends substantially within the space delimited by the tubular arch (130), so that said arch constitutes a means of grasping the chair to move it easily. , especially since the materials constituting the chair allow a lightweight construction.

According to another embodiment, the seat (1 10) is also made of a fiber-reinforced composite material comprising vegetable fibers. According to this particular embodiment, the seat is produced by a method of compacting consolidation of a stack of fibrous folds, implementing dynamic heating by induction of the mold, as described in document EP 2 694 277. This method implementation also makes it possible to integrate into the lamination of the composite constituting the seat, a printed decoration, in particular on the portion (112) acting as a cushion, which decor is then unalterable.

The use of a method employing induction heating of the mold, makes it possible to obtain a uniform temperature over the entire surface of the mold, and thus to obtain a very flattering appearance, free from defects in appearance and discoloration. , of the face of appearance of the seat, that said seat has or not a technical face, whether it is made of a plastic material, composite or light metal alloy. When the seat has a technical face, it is advantageously overmolded, especially by injection, on the preform.

Obtaining a uniform temperature in the mold and therefore the control of the viscosity of the molded material also makes it possible to mold decorations in relief or recessed on the various elements constituting the chair object of the invention.

Advantageously, the tubes constituting the feet and the hoop are also made by implementing a dynamic induction heating method, as described, for example, in document FR 2 915 053, using a braided preform comprising cometary polymer fibers. with the reinforcing fibers. These processes make it possible to quickly realize the structure of the chair according to a series production. The section of the tubes constituting the feet and the arch is an ovoid or polygon section advantageously of variable section between the two ends of each of these components. In order to obtain this variation of section, the braid constituting the preform is made on a solid core or in the form of an inflatable balloon, reproducing the variation of section.

The use of plastics and composite materials, shaped into molds for producing the structure of the chair which is the subject of the invention, makes it possible to produce dimensionally accurate pieces that easily assemble without play, that are not sensitive. to moisture and stable in dimensions. Thus, although light, the chair object of the invention is durable.

The rigid structure of the backrest and the seat allows to integrate a support (140) dorsolumbar, which according to an exemplary embodiment is included in the space delimited by the arch. Said lumbar support (140) is made of a fiber reinforced or non-reinforced polymer material comprising natural fibers. According to an exemplary implementation, said support is produced by a consolidating compacting method in the form as described in document EP 2 694 277 and comprises a decoration integrated with the lamination. Said support (140) is connected to the seat, for example by interlocking one of its ends in a then molded sheath or in the seat or by clipping and / or bolting on the frame (1 1 1) of said seat .

Figure 2, according to an exemplary embodiment the support (140) dorsolumbar and the arch (130) are curved towards the rear of the chair. According to this embodiment, the hoop is made by molding in a drawer mold to ensure its demoldability.

3, according to an alternative embodiment, the tubular arch (330) is made in two parts (331, 332), the two parts being connected by an assembly part (335), advantageously obtained by injection molding of a biobased polymer, reinforced or not by short fibers, themselves biobased. This embodiment avoids the use of a drawer mold for the realization of the tubular arch and thus reduce the investment required for the production of the chair object of the invention.

Returning to Figure 2, the free end of the thoracolumbar support and the nature of the material constituting it confer on said support a flexibility which allows it to be relatively adapted to the morphology of the user of the chair which is the subject of the invention. Said support (140) dorsolumbar being assembled with the seat, preferably without tools by clipping or interlocking, the chair object of the invention is advantageously proposed in kit with different supports dorsolumbar shapes, material, rigidity or different decor. Advantageously, said kit is proposed according to an online sales model where the client selects a seat and support assembly backrest with a base and a hoop so as to constitute a custom chair, which is easily sent disassembled by a courier service and assembled by the client.

The above description and the exemplary embodiments show that the invention achieves the goal of a comfortable, lightweight and durable chair with a back support easily customizable and achievable in series.

Claims

Chair comprising:

at. a tubular base (121, 122, 123, 124);

b. a seat (1 10) fixed to said base, said seat and said base forming the seat;

vs. a tubular arch (130) constituting the backrest and connected to two of the legs (123, 124) of the base;

d. a support (140) elastically dorsolumbar, comprising two ends, one of which is free and the other is linked to the seat, characterized in that the base (121, 122, 123, 124) and the hoop (130) tubular are composed of a fibrous reinforcement composite material comprising a natural fiber, in particular a plant fiber.

Chair according to claim 1, wherein the tubular arch (130) consists of a single piece.

Chair according to claim 1, wherein the connection of the support (140) dorsolumbar seat is a removable connection.

Chair according to claim 3, wherein the tubular section of the arch (130) is scalable between its connections to the two feet (123, 124).

Chair according to claim 3, wherein the tubular section of the legs (121, 122, 123, 124) of the base is scalable between their end intended to rest on the ground and their connection to the seat.

Chair according to claim 1, wherein the seat (1 10) is made of a plastic material.

Chair according to claim 1, wherein the seat (1 10) is made of a metallic material.

Chair according to claim 1, wherein the seat (1 10) comprises a crown (1 1 1) connecting with the base and a portion (112), said seat cushion, assembled with said crown.

9. Chair according to claim 1, wherein the support (140) dorsolumbar is made of a plastic material.

10. Chair according to claim 1, wherein the support (140) dorsolumbar is made of a composite material with fibrous reinforcement.

11. preconstituted assembly, or kit, comprising a chair according to claim 3 and several back supports.

12. preconstituted assembly, or kit, comprising a chair according to claim 8 and several cushions (1 12) of seat.