DE2448361C3 - Process for lamination of molded pieces with an elastic plastic film - Google Patents

Description

The invention relates to a method for laminating molded pieces with an elastic Plastic film that extends beyond the molded piece on all sides and in its edge area by a holding frame is fixed over the fitting, while it is stretched by negative or positive pressure on the Fitting is brought to rest.

To conceal such shaped pieces, it is known to close the shaped piece with a binding agent provided and then to bring the plastic film in a known manner with negative pressure to the plant. Here the outer zone of the film is completely retained in order to allow the film to be applied without creasing mechanical stretching. It has been shown, however, that, especially when curved in three axes Bodies with relatively deeply drawn bulges that need to be coated, it is not possible to insert a to ensure wrinkle-free application of the film without air pockets. These shortcomings will be Reinforced by foils made of very hard-wearing material.

The same applies to a known method according to DT-OS 14 79 017, with a molded body on the way the vacuum molding technique is covered with a coherent, heated plastic plate that is completely held in the outside area via a holding frame.

The object of the invention is to provide a method for laminating molded pieces with relatively strong To create bulges and / or curvatures through plastic films, which is a wrinkle-free system Foil can reach.

This object is achieved according to the invention in that the protruding over the shaped piece Edge area of the film in its outer zone over its entire circumference, significantly reducing the film material Has indentations.

This has the advantage that the film, before it assumes its end position, held like a spring and due to the cross-section reduction in the outer zone, the protruding area in the holding zone is used more for the flow of material and thus improves it, so that a wrinkle-free system the film is carried out on the molded piece. With simple means, the problems identified in the Lamination of such pieces of furniture eliminated

A simplification of the structure of the printing areas is achieved by the fact that a closed one over the film Cover film is arranged

Io of the drawing shows an embodiment of the invention for a molding formed in three axes with relatively deep bulges. It shows
F i g. 1 a fitting to be concealed,
F i g. 2 the shaped piece with an applied film and

3 shows a vertical partial sectional view of a device with the molded piece inserted for Laminating.

The molding 1 shown is in a Unterdruckgcstell 2 inserted and covered with a film 3

Previously, the film 3 receives 4 indentations 5 in the protruding Außenenzcne, which in this exemplary embodiment are evenly distributed on the outer zone 4, because of a relatively uniform flow of material is to be paid off. Through the indentations 5 are

Holding webs 6 formed. Additional indentations were made in the corner areas of the protruding outer zone 4 7 attached, as these areas are an extension of particularly large material expansion areas and thereby a pushing of the material from

the adjacent areas during the lamination is made possible without material accumulation can come.

The film 3 formed in this way is in the outer region of the holding webs 6 over a circumferential Holding frame 8 set by being connected to the vacuum frame 2. To the simple Sealing of the indentations 5, 7 provided film 3 and formation of a vacuum space 9 is on the Film 3 an additional stretchable cover film 10 is placed

After the film 3 provided for the lamination with the cover film 10 over the holding frame 8 is attached, a negative pressure is created by a pressure acting on the opening 11 of the negative pressure chamber 9 A vacuum pump was created, which brings the film into place without creases under mechanical stretching. Additionally is it is possible to bring the equipped Unferdruckgestell 2 in an autoclave, so that the film 3 through Negative and positive pressure is brought to bear on the molded piece 1 and where appropriate is still being heated.

In the case of mechanical stretching to apply the film 3 to the molded piece 1, the reduction in cross section of the clamped outer zone 4, the material continues to flow out of the protruding outer zone 4 possible, so that tensions within the coating are reduced. The slide will in principle It is held like a spring and allows the material to slide down, with the greatest possible stretching in the not to Coating serving edge areas are placed.

The material of the film 3 consists, for example, of a PVC-Fo-He coated with a polyvinyl fluoride compound.

For this purpose 2 sheets of drawings

Claims (2)

Patent claims: 1. Method for lamination of molded pieces with an elastic plastic film that covers all sides the fitting extends out and in its edge area by a holding frame above the fitting is fixed while it is stretched to the fitting by negative or positive pressure Concern is brought, characterized in that the over the shaped piece (1) protruding edge area of the film (3) in its outer zone (4) over its entire circumference Foil material has indentations (5, 7) that significantly reduce 2. The method according to claim 1, characterized in that a closed over the film (3) Cover film (10) arranged Ut