DE102004044315B4 - Method for producing an electrically heatable upholstery and / or molded foam element of a vehicle interior trim - Google Patents

Abstract

method for producing an electrically heatable upholstery and / or molded foam element (26), in which one with a flat Carrier layer (12) provided heating element (10) with its surface (24) of a body pointing heating conductor (14) placed on this and pressurized and heat adhering to the surface (24), after which the carrier layer (12) from the heating conductor (14) is removed, characterized in that the pressurization by means of a forming punch, which is an approximate negative form (20) the surface (24) to be provided with the heating element (10) of the body having.

Description

The The present invention relates to a process for producing a electrically heated upholstery and / or molded foam element with the features of the preamble of claim 1.

electrical Heatable upholstery elements such as vehicle seats have heating elements on, usually from a textile carrier material exist, which is connected to an electrical heating conductor. This Composite can partially during assembly with the seat cushion foam or over the entire surface bonded. The bonding process and its quality depends strongly from the ambient conditions, so that often no constant liability quality can be made sure. This can be the worst case manufacturing or Operating conditions under certain circumstances to detachment of the heating element lead from the foam. The resulting folds or kinks can be unfavorable circumstances to a failure of the heating element or fire damage to the upholstery to lead.

such flat Gluing can be more Disadvantages bring me, since the adhesive surfaces are largely impermeable to air. In addition, the textile carrier layer to disturb, as it is unnecessary in the Seat remains and can negatively affect the seat climate.

Out DE 37 25 408 A1 is a method for producing a surface electrically heated vehicle seat and / or a surface in the seating area of the vehicle with a stick-on pad known. The seat for the seat made of foam forms an independent part and is used for a variety of forms of seats. The pad is made of foam with an embedded heating element and can be covered with a desired fabric after it has been glued to the seat.

Out DE 41 26 188 A1 For example, a method for attaching a heating element between a top and a bottom material is known in which a heating element is bonded by means of a thermoplastic adhesive between two layers of fabric.

Out US 4865379 A is known a seat in which a recess is provided in a pad. In this recess, a depositor is used consisting of a foam block and a heating element mounted thereon.

Out EP 0143742 A1 is known a seat in which in a recess of a cushion, a foam block is used with a heating element.

The WO 01/19220 A1 describes a method for applying a heating element to a cushion element of a vehicle interior. The heating element has at least one heating conductor, which is laid in a loop. In the method, the heating conductor is applied to an intermediate carrier and bonded thereto, after which the intermediate carrier is placed with the heating conductor applied thereto on a surface of the cushion member which is to be connected to the heating conductor. The heat conductor is pressed against the surface, at the same time the adhesive layer is heated to bond the heating conductor with the surface. Subsequently, the intermediate carrier is removed, so that the padding element can be supplied for further processing.

One The aim of the present invention is to provide a method for Production of an electrically heatable upholstered or molded foam element to disposal to provide, in which a good adhesion between a heat conductor and the upholstery element is produced and the production technology as possible easy to make.

to Achieving these objectives will propose a procedure that the Features of claim 1. Features more advantageous Further developments of the invention will become apparent from the dependent claims.

An electrically heatable upholstered and / or molded foam element of a vehicle interior according to claim 1 has an at least partially elastic body, which is connected at a surface with a cladding layer. The body may in particular be a padding element or a molded foam part of a vehicle interior trim or the like. The cladding layer may, for example, be a covering material or a surface cladding. Between the surface of the body functioning as a carrier element and the cladding layer, an electric heating element is arranged with at least one heating conductor. According to the invention, the heating element is at least partially embedded in the surface of the carrier element and / or adhesively connected thereto, in particular adhesively bonded thereto. The adhesive bond or bonding can be formed, for example, in that the heating element is at least partially fused to the surface of the carrier element. According to the present invention, in the finished upholstery and / or molded foam element no further support structure or layer is provided, on which the heating element is applied. Instead, this is embedded directly in the elastic body of the upholstered or molded foam element without additional carrier layer, so that optimum air permeability is achieved. In addition, this can ensure a good heat transfer from the heating element to the cladding layer who the.

A Embodiment of the invention provides that the heating element under Pressurization and / or heat with the body connected is. The heat effect can in particular come about by the fact that the heating element with a heating voltage is applied, causing the heating conductor on his Operating temperature warmed up. In this way, optionally, a hot melt adhesive for producing a positive Adhesive bond between heat conductor and elastic body melted become. The heating conductor may, for example, an enclosure with a thermally activated Have adhesive. Such an adhesive may, for example, based on polyamide be prepared. Optionally, by heating, the elastic padding element be melted directly, for example, if this from a thermoplastic foam material (eg polyurethane foam or the like).

Of the At least one heating conductor of the heating element can, for example, a meandering contour or a meandering course have, so that a substantially uniform coverage of the cushion element guaranteed is. Possibly. the heating conductor can also have a spiral laying contour. The heating conductor can be made of metal, carbon fibers and / or an electric conductive Plastic be formed. The heating conductor may possibly also have a film structure which only minimally under the cladding layer of the Upholstered element signs.

One inventive method for producing an electrically heatable upholstered and / or molded foam element according to a Forms previously described Ausfüh provides that with a two-dimensional backing solvable connected heating element with the surface of the elastic body or Pad element facing heating element placed on this and pressurized and heat adhering to the surface is connected, after which the carrier layer removed from the heating element. According to the present invention is provided that the pressurization by means of a forming punch or a formula element, which is an approximate negative form of the with the Has heating element to be provided surface of the cushion element. This device or this form stamp is a largely to the contour of the cushion element matching negative image of acting foam type and is geometrically designed so that only a unique assignment to the with the heating element too Provided seat foam allows is. The carrier layer with the heat conductor applied to it can thus be clearly on the body be positioned.

The Pressurization is preferably carried out with a defined contact pressure and largely perpendicular to the surface of the body. This can be guaranteed be that the contact pressure largely uniformly distributed over the area of the heating element to be connected acts on this. This can be further provided that the acting on the surface Contact pressure is measured, for example by means of at least one pressure sensor. hereby In particular, an automated production can be made possible at each for Different types of upholstery guaranteed a defined contact force can be.

With the pressure drop is heated at the same time the heating element, For example. By voltage of the heating element with its operating voltage. This process can be automated with one on the respective seat type fixed set Heizzeitablauf, which only then initiated is when the pressure sensors correct placement of the device together with the heating element on the seat foam report.

to Making a good bond, the heating element can one Have hot melt adhesive, which melts under the action of heat and makes an adhesive bond with the cushioning member. Optional can the upholstery or molded foam element also from a heat consist of melting plastic foam.

To Completing the process, the carrier layer is removed. It remains Thus, the fixedly connected to the seat mold foam heating element, the one good adhesion form-fitting Connection to the carrier element of foam.

The Invention will be described below with reference to a preferred embodiment explained in more detail with reference to the accompanying drawings. there shows:

1 a perspective schematic view of a heating element, which is applied to a flat carrier layer,

2 a sectional view of the heating element according to 1 .

3 a sectional view of an inserted in a forming die heating element,

4 a sectional view of a manufacturing step in the manufacture of an electrically heatable cushion element according to the invention,

5 a further step in the production of the cushion element in a schematic sectional view and

6 a further step in the production of the cushion element in a schematic sectional view.

The schematic representation of 1 illustrates a heating element 10 consisting essentially of a flat carrier layer 12 and a heating conductor applied thereon 14 consists. The schematic sectional view of 2 clarifies the structure of the heating element 10 in which the heating conductor 14 on a surface of the carrier layer 12 is applied. The heating conductor 14 may in particular be a conventional heating strand of metal or carbon fibers or a heating conductor of electrically conductive plastic. The heating conductor can, for example, consist of an electrically conductive plastic film. The flat carrier layer 12 can in particular consist of a textile carrier material, for example a woven or knitted fabric or the like. The heating conductor 14 is on the carrier layer 12 applied in a meandering pattern to cover a large effective heating surface can. Furthermore, the heating element 10 a connection line 16 with a contact area 18 on. By means of the contact area 18 and the electrical connection line 16 is an impingement of the heating element 10 with an electrical supply voltage as soon as the heating element 10 located at its intended location. This may, for example, be a seat cushion or backrest cushion of a vehicle seat or the like. The heating element 10 is also suitable for heating other upholstery parts of a vehicle interior, eg. A door interior trim.

According to the present invention, it is provided that the heating conductor 14 detachable with the carrier layer 12 is connected, so that the carrier layer 12 after mounting the heating element 10 can be removed. The carrier layer 12 has only the function to maintain the intended Heizmediumanordnung to the assembly. Subsequently, the carrier layer 12 removed and disposed of as it is no longer needed.

The schematic sectional view of 3 clarifies this in a negative form 20 a forming punch o. The like. Inlaid heating element 10 that by means of the negative mold 20 can be applied to a correspondingly shaped molded foam part of a seat o. In a first method step for producing a cushion or molded foam element according to the invention, the carrier layer 12 of the heating element 10 with the heating conductor applied to it 14 in the negative form 20 inserted, whose contour is largely a surface contour of a cushion or molded foam element (see. 4 to 6 ) corresponds. The heating conductor 14 is on the negative form 20 opposite top 22 the carrier layer 12 , The negative form 20 Each must be designed so that it represents a negative image of the type of seat or upholstery foam to be applied. The negative form 20 is shaped so that only a clear assignment to the cushioning type to be applied is possible.

The schematic sectional view of 4 illustrates a process step in which the negative mold 20 with the heating element inserted therein 10 on a surface 24 a molded foam part 26 applied and with uniform force F on the molded foam part 26 is pressed. At the same time, the heating conductor 14 heated, which can preferably be done by means of a voltage application. The pressing force F is defined and applied uniformly, so that a uniform pressing of the heating element 14 to the surface 24 he follows. This pressing force F can, for example, by means of pressure sensors 28 be measured and controlled. By a time-defined heating of the heating element 10 and the defined application of force over a certain period of time, a positive connection between the surface 24 the molded foam part 26 and the heating conductor 14 getting produced.

The heating conductor 14 Optionally, it may be provided with a hot melt adhesive which, when heated, bonds to the surface 24 , but not with the carrier layer 12 manufactures. In addition, the heating conductor 14 by the contact force F in the surface 24 the molded foam part 26 be pressed, which can melt due to the heating and form depressions, in which the heating conductor 14 then embedded.

This process can be automated in an advantageous manner and run with fixed on the seat type heating time. The heating should only be initiated if the pressure sensors 28 a correct placement of the negative mold 20 together with the heating element 10 on the molded foam part 26 signal.

The schematic sectional view of 5 illustrates a subsequent process step, in which an adhesive connection between the heating conductor 14 and the surface 24 the molded foam part 26 is formed. The carrier layer 12 is still in adhesive connection with the heating conductor 14 , Subsequently, the carrier layer 12 from the heating conductor 14 be deducted (cf. 6 ), because the bond between the heating conductor 14 and the surface 24 the molded foam part 26 stronger than the adhesive bond between the heating conductor 14 and its carrier layer 12 , The in the 6 shown intermediate production stage illustrates this with the heating conductor 14 provided upholstered part, on the surface 24 then a panel or a fabric or leather cover o. The like. (Not shown) can be applied.

The molded foam part 26 For example, may consist of PUR foam or other suitable plastic foam material, the embedding and bonding with the heat conductor under the action of heat 14 allows.

The upholstery element according to the invention can in principle be any conceivable interior design in the vehicle, which can be provided with a heating device in the manner described. The molded foam part 26 does not necessarily have an elastic structure, but may also be relatively dimensionally stable.

When Such electrically heatable molded foam elements come in particular Seat cushion of vehicle seats in question. However, the elements can also be backrest cushion or cheek pads of vehicle seats.

The in the foregoing description, drawings and claims Features of the invention can both individually and in any combination for the realization the invention in its various embodiments of importance be. The invention is not limited to the above embodiments limited. Much more is a variety of variants and modifications conceivable by the idea according to the invention Use and therefore also fall within the scope of protection.

10

heating element

12

backing

14

heating conductor

16

connecting line

18

contact area

20

negative form

22

top

24

surface

26

Molded foam

28

pressure sensors

Claims (6)

Method for producing an electrically heatable upholstered and / or molded foam element ( 26 ), in which a with a flat carrier layer ( 12 ) provided heating element ( 10 ) with his to the surface ( 24 ) of a body-facing heating conductor ( 14 ) placed on this and under pressure and heat adhesion with the surface ( 24 ), after which the backing layer ( 12 ) from the heating conductor ( 14 ) is removed, characterized in that the pressurization is effected by means of a forming die, which is an approximate negative form ( 20 ) with the heating element ( 10 ) surface ( 24 ) of the body. A method according to claim 1, characterized in that the pressurization with a defined contact pressure (F) substantially perpendicular to the surface ( 24 ) of the body. A method according to claim 1 or 2, characterized in that on the surface ( 24 ) acting contact pressure (F) is measured. A method according to claim 3, characterized in that the contact pressure (F) with at least one pressure sensor ( 28 ) measured between the surface ( 24 ) of the body and the carrier layer ( 12 ) of the heating element ( 10 ) is arranged. Method according to one of claims 1 to 4, characterized in that the heating conductor ( 14 ) is at least partially coated with a hot melt adhesive, which is liquefied under heat and then cured. Method according to one of claims 1 to 5, characterized in that the upholstery or molded foam element ( 26 ) consists of a heat-melting plastic foam.