FI90650B - Method and apparatus for lining an article with at least one elastic piece - Google Patents

Abstract

In a process for covering an object by means of at least one flexible piece, a fluidized bed of particles (8) is covered by a flexible cloth (10), the flexible covering piece (12) is placed above said cloth, the object (13, 14) is placed above said cloth, pressure is applied to said object, deforming the flexible sheet and immersing the object in the fluidized bed until a mating imprint is formed in the latter. The covering can be effected by gluing, in particular with a previously applied heat-activated adhesive in which case the fluidized bed is obtained by means of a current of hot air at a temperature above the activation temperature of the adhesive. The process is particularly suitable for assembling and mounting seat covers. Also described is a device for implementing the process.

Description

1 90650

A method and apparatus for coating an article with at least one flexible body. - Förfarande och anordning för att bekläda ett föremäl med ätminstone ett elastiskt stycke.

The invention relates to a method and an apparatus for coating an article by means of at least one flexible body. It is particularly suitable for seat upholstery, which consists of a rigid support, an elastic foam layer and a fabric cover.

When coating an article with a resilient body that is to conform to the article, it is generally held in place by mounting molds shaped according to the article to be coated. This is the case, for example, in EP Patent Application No. 0 223 312, which discloses seat upholstery. The essential defect of mounting molds is that they are specially adapted to an object of a certain size and shape. The manufacturer must have as many molds available as the type of object to be clad. Mechanical installation methods do exist, but they are generally time consuming, unsuitable for automation, and impossible to apply to completely cladding objects due to the lack of suitable zones for gripping the object.

The present invention relates to a new method for cladding an object and to an apparatus for carrying out the method, which avoid the errors of known cladding methods.

The method according to the invention is characterized in that the method produces a fluidized bed of particles on which said flexible fabric is placed and the object is pressed into the Lei bed until a depression is formed, whereby the flexible body presses against the shapes of the object and assumes these shapes.

The attachment of the flexible body to the article can be accomplished by holding the grate in a floating state and permanently applying a pressure of 2,90650 to the article. Once the object has been pressed into the fluidized bed, it is also possible to stop the fluidization of the particles (interrupting the gas flow that causes this) and when the particles have stopped against each other it is possible to stop applying pressure to the object that remains in the deflection (which has become a solid grate). then apply suction to the grate to secure the particles together.

When coating a set of similar articles, it is possible to use the first method repeatedly for each article. It is also possible to perform the coating of the first object using the second embodiment, then remove said first object by holding the grate in a fixed state, and placing each subsequent object and its resilient body in the fixed grate of the first object to form a depression for attaching the resilient body to the object.

The method according to the invention can be used to coat objects of any shape without having to be made in advance by casting or machining a mounting mold for each type of object. Such a method is particularly advantageous for coating objects which may be of different shapes or sizes.

It should be noted that according to EP patent application 0 223 312, the fastening of the resilient body can be performed by means of a tensioning wire which is fitted around said resilient body and tensioned at the end of the operation to fold and tighten its edges around the object.

The attachment may also be performed by any other method; by stapling to the back of the article, gluing ... the gluing of the flexible body to the shapes of the article can be combined with the method of the above application (which can tighten the edges of said piece 3 90650 on the back of the article).

The invention relates to a special fastening method in which gluing is performed with a heat-activated glue, wherein the glue is activated by a flow of fluidizing gas which is heated to a temperature higher than the activation temperature of the glue.

The article to be covered may consist of several prefabricated parts, in particular a rigid support and a layer of foam in the case of a seat upholstery. With the method according to the invention, in which gluing with a heat-activated glue, cladding and assembly with glue can be carried out in one operation, by activating the glue due to the flow of hot fluidizing gas.

The invention relates to a device for coating an article by means of at least one flexible body. The device comprises the following combination: - a surface-open chamber with a gas supply system at the bottom and a dispenser with a particle bed above it for fluidizing said bed, - a flexible fabric known per se arranged above the particle bed and fixed to the chamber circumference so as to change in its shape, - a pressing member known per se located opposite the open surface of the chamber and adapted to move farther or closer to said chamber, and - means known per se for moving the pressing member relative to the chamber.

Other features, objects, and advantages of the invention will become apparent from the following description with reference to the accompanying drawings, which show embodiments of the invention.

In the drawings: 4 90650 - Fig. 1 is a vertical section of the rear axis of the device, - Fig. 2 is a section showing the grate in a fluidized scale on a larger scale, - Figs. 3, 4, 5, 6 and 7 illustrate the steps of the coating process,

The press shown by way of example in Figure 1 is of the same type as shown in Figures Θ and 9 of the above-mentioned EP patent application 0 223 312. It is intended to perform assembly and coating of the coating. Said press comprises the general members already described in this prior application: a body 1, a pressing member formed by a plate or crossbar 2, a lever 3 supporting the pressing member 2 for moving it vertically, a plate 4 vertically for the member 2, hooks 5 for tensioning details and their use).

According to the present invention, the plate 4 has an associated chamber 6. The chamber, which is open at the upper surface, contains a fluidizing-dispensing device 7 at its lower part, which in the example consists of a microporous sheet made of wood extrudate. Above it is a particle bed B consisting of a large number of glass microspheres; a fluidized air flow can pass through the dispensing device 7, the inlet pipe 9 of which directs through the plate 4 and the lower part of the chamber.

The glass beads have a grain size distribution of between 75 and 150 microns and a density of between 2.3 and 2.8 (in the example, the density is 2.5). The pipes 9 are connected to an air supply system (not shown) which is connected to the flow heating means. In the example, the supply system and the dispenser 7 are arranged to allow air to be dispensed into the chamber at a linear velocity between 1.5 Vmf and 6 Vmf (at the direct section of the chamber) where Vmf is the minimum fluidization velocity of the glass spheres (on the order of 0.9 m / s). .

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The air heating elements can consist of a resistor of the order of 2 kilowatts, and the flow of the air blowing devices is 3 about 1.5 m / mn at a relative pressure of 60 mb. The air flow can thus be heated to a temperature of Θ0-100 C.

In Figure 1, the particle bed is assumed to be at rest (without air supply). Above it is a resilient fabric 10 attached to the circumference of the chamber. The flexible fabric is porous so that airflow can pass through but the glass balls are blocked. The fabric may be a synthetic material woven in small loops (or consist of a combination of several airy mats).

In the example, the fabric 10 is lined with a special flexible foam layer 11 with open cells, which tends to follow the shapes of the object to be printed above it. The foam is used to smooth the edges of the coating.

Figure 2 shows a ball bed in a fluidized bed with fluidized air coming from a tube 9. The bed expands and behaves like a flowing (but compressible) bed with an average density of the order of 1.5.

In the method according to the invention, a piece of fabric 12 is initially installed above the hover grate, which is intended to cover the seat upholstery (Fig. 3). The piece of fabric is cut to a suitable shape and its rim 12a may have a tension wire such as EP patent application 0 223 312.

The parts of the cladding are then fitted to the body 12, in the example a rigid support 13 and a foam layer 14 (Fig. 4). Prior to that, glue has been applied to opposite surfaces of the fabric chapels 12, foam 14 and support 13. Use a heat-activated adhesive which becomes adhesive by heating to approx. 65 ° C. The adhesive may in particular be a Chimiprene C-GEX type polyurethane-based adhesive.

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The pressing member 2 is then moved vertically to the pressure medium of the assembly and not to the fluidized bed as shown in Fig. 5. The depression height is designed so that the coating 12 fully follows the shape of the foam 14 and that the foam is slightly compressed to a very uniform size. In this position, the whole is in a stable position.

The heating element is started and 80-85 degree hot air activates the adhesive; Reactivation is achieved with a heating time of 15-30 seconds.

During this time interval, the ends of the tension wire running along the edge 12a of the fabric piece 12 are tensioned and wedged to fold and hold the piece 12 behind the upholstery (Figure 6).

The finished part is removed by lifting the pressing member 2, whereby the next object, possibly of different shape and size, can be processed immediately.

It should be noted that the air can be suspended, if necessary, before the freshly finished object is removed, and in this case the bed (which has become solid) retains the shape of this object as shown in Fig. 7. With this variation, if necessary, similar objects (without air distribution) can be placed in the depression formed by the first object.

Figure 8 shows, in a variation, a device adapted to allow the balls to stop completely with one another in order to avoid deformations of the depression in the above embodiment. The fabric 10 is in this case tight and the distribution gas outlet means 15 provided with a stopcock 16 are connected to the chamber so that air can escape during the air distribution steps (whereby there are several outlet lines around the chamber to maintain a symmetrical flow).

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The inlet of the chamber can be connected via a valve 17 to either the air supply system 18 or to the suction members 19. When the supply system 18 has been stopped, the tap 16 is closed and the valve 17 is connected to the suction members 19 which are actuated. The particle bed is then subjected to suction, which makes the particles immobile with respect to each other and allows the deflection of the first object to harden better and remain more stable.

Claims (13)

A method of lining an article with at least one elastic piece (12), in which method the elastic piece (12) is placed above an elastic tissue (10), the article (13, 14) being arranged on the elastic piece, pressure is exerted on the article (13, 14) so that the shape of the tissue (10) and the elastic piece (12) change, and the elastic piece is attached to the article, characterized in that in the method a fabric bed (8) is produced. of particles on which said elastic tissue (10) is placed, and the article (13, 14) is pressed into the fluidized bed (8) until an imprint is formed, the elastic piece (12) s junking into the shapes of the article and acquiring these forms. Method according to claim 1, characterized in that the bed is poured in a swirling state by continuously exerting pressure on the article during the time that the elastic piece adheres to said article. 3. A method according to claim 1, characterized in that when the article is pressed into the fluidized bed, the vortex is terminated and when the particles are stopped against each other, the pressure exertion on the article which is poured into the bed formed during the elastic piece adheres to said former ceases. . 4. A method according to claim 3, characterized in that, upon completion of swirling, the bed is subjected to suction to render the particles immobile in relation to each other. Method according to claim 3 or 4 for coating a series of like articles alternately, characterized in that in the method a first article (13, 14) is covered, the first article (13, 14) is then removed by tilting the bed (8). ) in solid state, and each of the following articles (13, 14) and its elastic piece (12) is arranged in the impression formed by the first piece of the fixed bed (8), to attach said elastic piece (12) to the object (13, 14). Method according to any one of claims 1, 2, 3 or 4, characterized in that in the process adhesive is spread at least on one of the opposite surfaces of the elastic piece (12) and the article (13, 14) so that the attachment is done by gluing as the elastic piece (12) is pressed against the article (13, 14), 7. A method according to claim 6, characterized in that on the elastic piece (12) and / or on the article (13, 14.) is spread in advance in heat activatable glue, a fluidized bed (8) is formed by a hot air stream which divides over the lower part of the bed (8) at a temperature higher than the activation temperature of the adhesive, the article ((13, 14) is then left in place until the elastic piece (12) is glued to it). The method according to claim 7, which relates to the lining of a seat, which seat consists of a rigid support (13) and a foam layer (14), the support (13) and the layer (14) having said. . method can be assembled and lined with the elastic piece (12), characterized in that in the method: - spread in heat activatable glue at least on one surface of the opposite support (13) and the foam layer (14), - spread in heat activatable glue at least on a surface of the opposite elastic piece (12) and the foam layer (14), - the elastic piece (12) is adapted above the fluidized bed (8) covering the tissue (10), and then the foam layer ( 14) in contact with the elastic piece (12) and the support (13) in contact with the foam layer (14), 14 90650 - exert a pressure on the support (13) so that it is all pressed into the fluidized bed, while the foam layer (14) compressed. - the whole thing is removed when the time is activated. 9. Apparatus for covering an object, characterized in that it comprises in combination: - a chamber (6) open to its upper surface with a gas supply system (9) and a distribution device (7) at its lower part , above which is found a particle bed (8) for swirling said bed, - an elastically known tissue (10), adapted above the particle bed (8) and attached to the perimeter of the chamber so that it can change its shape, - a pressure member (2) known per se located opposite the open surface of the chamber (6) and arranged to remove or approach said chamber, and - per se known means (3) for moving the pressure member in relation to the chamber. 10. Apparatus according to claim 9, characterized in that the particle bed (8) is a ball bed whose grain size distribution is between 74 and 150 microns and density between 2.3 and 2.8, and the gas supply system (9) and the distribution device (7). arranged to allow a gas distribution to the chamber at a linear velocity between 1.5 Vmf and 6 Vmf, with Vmf being the minimum swirling velocity of the balls Apparatus according to either of Claim 9 or 10, characterized in that the elastic tissue (10) located above the particle bed (8) is a porous tissue adapted to pass through the air stream. while the bullets are stopped. Device according to any one of claims 9, 10 or 11, characterized in that it comprises means for holding the air stream. is 90650 Device according to any one of claims 9, 10 or 12, characterized in that it comprises a dense tissue (10), means (15) for removing the distributed gas and suction means (19) connected to the chamber for exerting suction. on the particle bed (8).