FR2816262A1 - Trim component e.g. motor vehicle seat headrest is made by filling textile sleeve and extruded plastic pre-form with padding material - Google Patents

Abstract

The trim component is made from a knitted textile sleeve (1) with an inner tubular plastic pre-form (8) extruded coaxially inside it. The sleeve and pre-form are then placed in a mould (6) and the preform is blown so that it fits against the sleeve to form a shell that is then filled with a padding material before removal from the mold. An Independent claim is also included for a trim component.

Description

<Desc / Clms Page number 1>

PROCESS FOR THE PRODUCTION
OF A TRIM ELEMENT
The present invention relates to a method for producing a upholstery element, in particular an automobile, such as a headrest, and more particularly of such an element comprising at least one textile covering and a padding material.

 The methods of the prior art use at least one textile blank, complexed or not, and include cutting this blank, then assembling the elements thus cut to obtain a three-dimensional envelope open at least on one part. After its custom, this envelope is on its reverse side and must therefore be put back on the right side. Next, a reinforcing reinforcement and a padding material are incorporated into this envelope, for example by a process of the type known as in sit)).

These methods have the drawback of linking a large number of complex steps, some of which can only be carried out manually. This results in manufacturing times, and therefore high costs.

The present invention aims to overcome these drawbacks.

More particularly, the present invention aims to provide a method in which all the main steps of manufacturing a packing element are carried out in a single sequence.

To this end, the subject of the invention is a method for producing a upholstery element, in particular an automobile, such as a headrest, said element comprising at least one textile covering and a padding material, characterized by it includes the steps of:

<Desc / Clms Page number 2>

 - knitting a sheath to form said covering; - Extrude from an extrusion nozzle substantially coaxially to and in the center of said sheath, a tubular parison made of plastic; - placing the sheath and the parison in a mold - blowing said parison to press said sheath against the walls of the mold to form an envelope; - injecting said padding material into the envelope, and - unmolding the assembly thus obtained.

The method according to the invention therefore essentially consists in producing the coating by knitting, then in pressing this coating against the walls of a mold by extrusion-blowing of the parison, and finally in injecting the padding material into the envelope formed by the coating and the plastic material blown from the parison. These operations can be performed in sequence and can be easily automated, as can the transition from one to the other.

In addition, a practically finished product is directly obtained. only embellishment operations possibly remaining necessary.

The method according to the invention can also include the step of introducing an insert inside the sheath prior to the blowing step.

In the case of a headrest, this insert can for example be constituted by mounting pins and an adjustment mechanism.

This insert can in particular be inserted inside the parison.

<Desc / Clms Page number 3>

Also in a particular embodiment of the invention, said sheath is accumulated on a support after knitting.
The end of said sheath can be clamped by a driving and guiding clamp and said sheath can be deployed around said parison after extrusion of the latter.

 Also in a particular embodiment, a filling nozzle for the stuffing material is produced in said plastic material of the parison during the blowing step.

 More particularly, said filling nozzle can be formed opposite to said injection nozzle, the mold being inverted before injection of the padding material.

Excess material, for example the filling tip, can then be cut after demolding.

A hubcap can be placed over the cut areas. The invention also relates to a device for producing a trim element, in particular an automobile, such as a headrest, said element comprising at least one textile covering and one padding, this device being characterized in that it comprises: - means for extruding from an extrusion nozzle disposed substantially coaxially with, and at the center of a knitted sheath, a tubular parison made of plastic; - a mold ; - Means for blowing said parison to press said sheath against the walls of the mold; and

<Desc / Clms Page number 4>

means for injecting said stuffing material into the envelope thus obtained.
This device may further comprise means for knitting said sheath and means for its positioning around said extrusion nozzle.

 This device can also include a driving and guiding clamp for the end of the sheath.

 We will now describe, by way of nonlimiting example, an embodiment of the invention applied to a headrest, with reference to the appended schematic drawing in which: - Figure 1 illustrates the first steps of the method according to the invention ; - Figures 2 and 3 illustrate the following two steps; - Figure 4 illustrates the following steps of the method; - Figure 5 is a sectional view showing in more detail one of the steps of Figure 4; - Figure 6 illustrates another step of the method; - Figure 7 is a perspective view of the finished product; and - Figure 8 is a detail view in section.

We see in Figure 1 a textile sheath 1 from a circular knitting machine 2 of conventional type, or capable of providing a three-dimensional sheath. Such knitting looms are known so that loom 2 will not be described in more detail. The sheath 1 is therefore deformable either by the characteristic of the wire used in the context of a

<Desc / Clms Page number 5>

tricotage sur métier conventionnel, soit par déformation du support de tricotage dans le cas d'un tricotage sur métier tridimensionnel
La gaine 1 ainsi tricotée est emmagasinée sur un support tronconique
3 et son extrémité inférieure est pincée dans une pince 4 d'entraînement et de guidage
Le support 3 muni de la gaine 1 et de la pince 4 est alors positionné autour d'une buse 5 d'extrusion-soufflage de tout type connu. Cet ensemble est disposé au-dessus d'un moule 6 en deux parties. Ce moule 6 forme une cavité de moule à parois 7.

knitting on conventional loom, either by deformation of the knitting support in the case of knitting on three-dimensional loom
The sheath 1 thus knitted is stored on a frustoconical support
3 and its lower end is clamped in a clamp 4 for driving and guiding
The support 3 provided with the sheath 1 and the clamp 4 is then positioned around a nozzle 5 of extrusion blow molding of any known type. This assembly is arranged above a mold 6 in two parts. This mold 6 forms a mold cavity with walls 7.

 The parison 8 coming from the nozzle 5 descends by gravity. The sheath 1 fitted with the clamp 4 then descends around this parison and the assembly constituted by the sheath and the parison is placed between the two parts of the mold 6.

The mold cavity 6 is open to the outside via passages 9 for the pins 10 of an insert 11. The insert 11 is here constituted by a reinforcement and mounting frame for the headrest.

The mold is then closed as shown in FIG. 2 and the blowing is carried out in a known manner as shown in FIG. 3.

The blowing operation leads to press the parison 8 and the sheath 1 against the walls 7 of the mold 6. This operation leads to the formation of a complexed envelope constituted by the sheath and the material of the parison, part of the insert being trapped inside this envelope.

It will be observed in FIG. 3 that the mold 6 is shaped so that the lower end of the envelope forms a filling nozzle 12 for a stuffing material.

<Desc / Clms Page number 6>

The viscosity state linked to the temperature of the parison 8 as well as its chemical constitution ensures the connection between the textile of the sheath 1 and the parison.

 The nature of the parison and its thickness are chosen so that the headrest provides the desired comfort.

Once the blowing operation has been carried out, the mold 6 is turned over as shown at 13 in FIG. 4 so as to allow the injection of the padding material by the nozzle 12. This injection is carried out from a nozzle d injection 14. After the assembly has matured in the mold 6 as shown in 16, the latter returns to its initial position as shown in 17.

The cutting of the textile, parison and end piece surpluses 18 is here carried out by a mechanical system integrated into the mold 6. After this cutting, the mold is opened and the assembly produced 19 is extracted therefrom.

A peripheral ring 20 is then mounted on the headrest so as to embellish the cutting areas.

Claims (13)

 1 Method for producing a trim element, in particular an automobile, such as a headrest, said element comprising at least one textile covering and a padding material characterized in that it comprises the steps consisting in: knitting a sheath (1) for forming said coating; - Extruding from an extrusion nozzle (5) substantially coaxially to and at the center of said sheath (1) a tubular parison (8) made of plastic; - place the sheath and the parison in a mold (6); blowing said parison to press said sheath against the walls (7) of the mold (6) to form an envelope;

 injecting said padding material (15) into the envelope; unmold the assembly (19) thus obtained. 2. The method of claim 1 further comprising the step of introducing an insert (11) inside the sheath (1) prior to the blowing step. 3 The method of claim 2 wherein said insert (11) is inserted inside the parison (8). 4 Method according to any one of claims 1 to 3, wherein said sheath (1) is accumulated on a support (3) after knitting. <Desc / Clms Page number 8>  5 Method according to any one of claims 1 to 4, wherein the end of said sheath (1) is clamped in a clamp (4) for driving and guiding and said sheath is deployed around said parison (8) after extrusion of the latter.  6 Method according to any one of claims 1 to 5, wherein a filling nozzle (12) for the padding material (15) is made of said plastic material of the parison during the blowing step.  7 The method of claim 6, wherein said filling nozzle (12) is formed opposite to said injection nozzle and the mold is inverted before injection of the padding material. 8 A method according to any one of claims 1 to 7, wherein the excess material (18) is cut after demolding. 9 The method of claim 8, wherein a cover (20) is disposed over the cut areas. 10. Device for producing a lining element, in particular an automobile, such as a headrest, said element comprising less a textile covering and a padding material, characterized in that it comprises: - means for extruding from an extrusion nozzle (5) positioned substantially coaxially with and around a knitted sheath (1), a tubular parison (8) made of plastic; - a mold ; - Means for blowing said parison (8) to press said sheath (1) against the walls (7) of the mold (6); and <Desc / Clms Page number 9>  - Means for injecting said padding material (15) into the envelope thus obtained. 11. Device according to claim 10, comprising means (2) for knitting said sheath. 12. Device according to any one of claims 10 and 11, comprising means (3) for the establishment of said sheath around said extrusion nozzle. 13. Device according to any one of claims 10 to 12, comprising a clamp (4) for driving and guiding the end of the sheath.