KNITTED ARTEFACT WITH HEAT SHRINKING YARNS

Abstract

An assembly is described for chairs, armchairs, sofas and the like, comprising a knitted artefact (1) and sliders (12). The artefact (1) comprises a multilayer and two ends (11) of tubular shape for fixing the multilayer, wherein the multilayer comprises a knitted fabric front layer (2) and a knitted fabric rear layer (3) fixed to sliders (12) of the artefact (1) at said two ends (11). The artefact (1) further comprises heat-shrinking yarns (5) associated with the multilayer, wherein the heat-shrinking yarns (5) are fixed with a series of connection points (7) spaced apart to the sliders (12) so as to develop in weft between the two ends (11) of the artefact (1).

Claims

1. Assembly for chairs, armchairs, sofas and the like, comprising a knitted artefact and sliders, wherein the artefact comprises a multilayer and two ends of tubular shape for fixing the multilayer, wherein the multilayer comprises a knitted fabric front layer and a knitted fabric rear layer fixed to the sliders at the two ends, wherein the artefact also comprises heat-shrinking yarns fixed to the multilayer, wherein the heat-shrinking yarns are fixed with a series of connection points spaced apart to the sliders so as to develop in weft between the two ends of the artefact, wherein the heat-shrinking yarns are fixed to the knitted fabric rear layer at an external part of the knitted fabric rear layer, with a further series of the connection points spaced apart, the knitted fabric front layer comprises a plurality of plastic elements spaced apart, the plastic elements penetrate the knitted fabric.

2. The assembly according to claim 1, wherein a connection point is provided for every five or more beatings up of the knitted fabric rear layer.

3. The assembly according to claim 1, wherein the number of the heat-shrinking yarns is less than 20% of total yarns of the artifact.

4. The assembly according to claim 2, wherein the number of the heat-shrinking yarns is between 3% and 8% of total yarns of the artefact.

5. The assembly according to claim 1, wherein the multilayer comprises a padding between the knitted fabric front layer and the knitted fabric rear layer.

6. The assembly according to claim 1, wherein the artefact has a tubular shape between the two ends.

Description

DESCRIPTION OF THE DRAWINGS

[0029] These and other features of the present invention will become further apparent from the following detailed description of practical embodiments thereof illustrated by way of non-limiting example in the accompanying drawings, in which:

[0030] FIG. 1 shows a front perspective view of a portion of an artefact according to the present invention;

[0031] FIG. 2 shows a rear perspective view of a portion of the artefact;

[0032] FIG. 3 shows a perspective bottom view of an end portion of the artefact;

[0033] FIG. 4 shows the enlarged content of circle B of FIG. 1;

[0034] FIG. 5 shows a side view of a portion of the artefact.

DETAILED DESCRIPTION OF THE INVENTION

[0035] A knitted artefact 1 for chairs, armchairs, sofas and the like, comprises a knitted fabric front layer 2, a knitted fabric rear layer 3 and, where appropriate, a padding between said layers 2, 3. Knitted fabric front layer 2 means the layer with which a user comes into contact. Chairs and armchairs are generally understood to be products for the seating of users, e.g. car seats, aircraft seats, wheelchairs and more.

[0036] The padding consists of a filament weave which can be connected to the layers 2, 3 by machine or inserted in the gap between layers 2, 3 without any particular bonding.

[0037] The artefact 1 further comprises a plurality of heat-shrinking yarns 5.

[0038] The layers 2, 3 form a tubular knitted multilayer.

[0039] The artefact 1 comprises two tubular ends 11.

[0040] The heat-shrinking yarns 5 are connected to the ends 11 of the artefact 1 at sliders 12 inserted in said ends 11 which develop in an orthogonal direction with respect to the heat-shrinking yarns 5.

[0041] As apparent in FIG. 3, the layers 2, 3 are connected at these ends 11.

[0042] The heat-shrinking yarns 5 develop in weft between the two ends 11 at which they wind to have a solid bond.

[0043] Said ends 11 of the artefact 1 allow the attachment to rigid supporting structures of the chair, sofa or armchair, thus forming seat assemblies that therefore comprise a supporting structure and a supporting knitted fabric comprising said artefact 1.

[0044] The layers 2, 3 create a tubular structure which can enclose a padding, while the heat-shrinking yarns 5 are positioned outside the knitted fabric rear layer 3 (FIGS. 2 and 3), namely the layer which is not visible in a seat or not in contact with the user, for example a rear portion of a chair backrest.

[0045] A discrete set of appropriately spaced connection points 7 binds the heat-shrinking yarns 5 on the outside of the knitted fabric rear layer 3 with a type of hook known as “English”.

[0046] The heat-shrinking yarns 5 are free on the knitted fabric rear layer 3, between the two ends 11, within said connection points 7.

[0047] Preferably a connection point 7 is provided at least every five beatings of the knitted fabric rear layer 3, wherein beating means a direction of adjacent rows of warp yarns of the knitted fabric rear layer 3. At least every five beatings means that it can be every five or more beatings.

[0048] Preferably, the number of heat-shrinking yarns 5 is less than 20% of the total yarns of the artefact 1, even more preferably between 3% and 8%.

[0049] Advantageously the technical effect described below is optimized by increasing the cost-effectiveness of the final product.

[0050] Even at the ends 11, the heat-shrinking yarns 5 are hooked “in English” with connection points 7. The heat-shrink yarns 5 are wound to the sliders 12 thus creating a solid connection.

[0051] Once the artefact 1 has been made with the heat-shrinking yarns 5 configured in a straight line between the ends 11, as shown in FIGS. 2 and 3, heat is applied to the knitted fabric rear layer 3, e.g. steam, and said heat-shrinking yarns 5 shrink permanently and irreversibly due to their intrinsic properties.

[0052] Advantageously the artefact 1 shrinks only underneath, namely only the knitted fabric rear layer 3 shrinks.

[0053] The knitted fabric front layer 2 does not shrink because the heat-shrinking yarns 5 are not bound to the knitted fabric front layer 2.

[0054] As a result, a distancing movement of the knitted fabric front layer 2 away from the knitted fabric rear layer 3 is achieved, namely a three-dimensional effect considering the bonding of the knitted fabric front layer 2 with the slider 12 at the ends 11. In the case of a seat, said movement consists of a raising of the knitted fabric front layer 2, namely a padding effect is achieved. In the absence of padding between the two layers, a real pocket is created.

[0055] In case of processing a padding in parallel between the layers 2, 3, the permanent shrinkage of the heat-shrinking yarn 5 prevents the extension and flattening of the simultaneously processed padding in the gap between the two layers 2, 3. The padding tends to flatten when extended and remains raised. Therefore, once the artefact 1 is tensioned in the chair assembly, the padding remains hanging on the knitted fabric rear layer 3 to which the heat-shrinking yarns 5 are hooked “in English” under tension.

[0056] Said technical effect also varies according to the number of heat-shrinking yarns 5.

[0057] The presence of padding also varies said technical effect; if the padding is processed simultaneously with layers 2, 3, the machine programming can define padding of variable density and height.

[0058] The independence of the heat-shrinking yarns 5 with respect to the knitted fabric front layer 2 allows the latter to remain flexible and deformable.

[0059] The function of the sliders 12 at ends 11 is very important because they define a stable bond for both the layers 2, 3 and the heat-shrinking yarns 5, without the shrinkage effect of the heat-shrinking yarns 5 being applied to the knitted fabric front layer 2.

[0060] Advantageously the knitted fabric front layer 2 undergoes a completely different technical effect with respect to the knitted fabric rear layer 3.

[0061] The artefact 1 according to the present invention meets the user's comfort needs with simple and cost-effective technical means.

[0062] Said technical effect is even more pronounced when the knitted fabric front layer 2 is of the “origami” type, namely it has an intrinsic three-dimensional deformability. It is worth noting that in FIGS. 1, 4 and 5, the knitted fabric front layer 2 is of the “origami” type, but this technical distancing effect is present even if the knitted fabric front layer 2 is of the standard type, namely not of the “origami” type.

[0063] In more detail, in the artefact 1, the knitted fabric front layer 2 of the “origami” type comprises a plurality of plastic elements 21 spaced apart to create the “origami” effect, namely a three-dimensional deformability, in particular in a direction orthogonal to the surface of the fabric.

[0064] The knitted fabric front layer 2 of the “origami” type is made using a 3D printing process (3D printer), or preferably a plastic injection moulding process.

[0065] It is generally a plastic moulding process which takes place starting from an artefact 1 already comprising said knitted fabric layers 2, 3 fixed to the sliders 12 at the ends 11, and the heat-shrinking yarns 5 hooked “in English” under the knitted fabric rear layer 3 and at the ends 11.

[0066] In more detail, the knitted fabric front layer 2 is placed on a support, preferably metallic, e.g. aluminium, to isolate the knitted fabric rear layer 3 during the process of adding plastic material. Basically, the support is interposed between the layers 2, 3.

[0067] The plastic material printed on top of the knitted fabric front layer 2 creates a plurality of plastic elements 21 which integrate with the knitted fabric front layer 2 conferring localized rigidity to the knitted fabric front layer 2. FIG. 5 shows how the plastic elements 21 penetrate the knitted fabric front layer 2.

[0068] Advantageously, the knitted fabric rear layer 3 is not affected by the process of adding plastic material.

[0069] Said plastic elements 21 have a variable design according to the printing control or the shape of the mould and are spaced to leave areas in the knitted fabric front layer 2 free from plastic elements 21.

[0070] Advantageously, said free areas of fabric are deformable, thus allowing three-dimensional deformability of the knitted fabric front layer 2 of the “origami” type.

[0071] At the end of the printing process, the knitted fabric front layer 2 of the “origami” type is easily separated from the support because said free areas of fabric create contact discontinuities following the creation of the plastic elements 21.

[0072] Once the plastic elements 21 have been made, heat is applied to the knitted fabric rear layer 3 which contains the heat-shrinking yarn 5: advantageously, the knitted fabric rear layer 3 shrinks.

[0073] Since the two layers 2, 3 are bound at the ends 11, this shrinkage causes a shortening of the distance between the two sliders, thus raising/activating the origami-shaped plastic elements 21.

[0074] If the knitted fabric front layer 2 is of the “origami” type, no padding is required between the layers 2, 3 because the three-dimensional effect is given by the origami.