Method of producing motor vehicles and tool suitable therefor

1. A method of producing motor vehicles comprising:

a. coating a motor vehicle body with at least one paint,

b. drying and/or hardening the at least one paint,

c. mounting attachment parts on load-bearing components of the motor vehicle body that has been coated with the at least one paint that has been dried and/or hardened, and

d. applying an adhesive film comprising an adhesive layer to a surface of the motor vehicle body that has been coated with the at least one paint that has been dried and/or hardened or at least one attachment part mounted thereon,

wherein, to apply the adhesive film,

e. the adhesive film is positioned between the surface and an elastic membrane with an automated system, and

f. the elastic membrane is transformed at least in selected regions into a curved state with a convex and a concave side and is brought into contact with the surface with the convex side in front such that the adhesive layer of the adhesive film is pressed onto the surface by the membrane over an entire surface area of the adhesive layer, and a negative pressure is applied in a region between the surface and the membrane by using a frame that forms, together with the surface to be provided with the adhesive film and the membrane, a negative-pressure chamber in which the adhesive film is arranged and into which the membrane can curve when the negative-pressure chamber is subjected to a negative pressure,

wherein the negative pressure is varied depending on the pressure that the membrane exerts via the adhesive film on the surface to be provided with adhesive.

2. The method as claimed in claim 1 , further comprising:

a. transforming the elastic membrane at least in selected regions into the curved state with the convex and the concave side, and

b. with the automated system bringing the membrane up to the surface with the convex side in front until the adhesive layer of the adhesive film is pressed onto the surface by the membrane over the entire surface area of the adhesive layer.

3. The method as claimed in claim 1 , further comprising:

a. bringing the elastic membrane up to the surface in one step with the automated system, and

b. transforming the membrane at least in selected regions into a curved state with a convex and a concave side, and

c. intensifying a curvature of the membrane until the adhesive layer of the adhesive film is pressed onto the surface over the entire surface area of the adhesive layer by the convex side of the membrane.

4. The method as claimed in claim 1 , wherein

the adhesive film comprises a carrier film having the adhesive layer on one side and a paint layer on the other side, and at least one of:

a. the carrier film is a plastic film, a metal film or a metal/plastic composite film,

b. the carrier film has a thickness of 10 μm to 120 μm,

c. the adhesive layer has a thickness of 10 μm to 80 μm,

d. the adhesive layer has a uniform thickness,

e. the adhesive layer consists of a homogeneous adhesive mass,

f. the adhesive layer has a surface area of 10 cm 2 to 8 m 2 , and

g. the paint layer has a thickness of 20 μm to 150 μm.

5. The method as claimed in claim 1 , wherein at least one of:

a. the negative pressure is set to a value of ≤ 750 mbar, and

b. the membrane is transformed into the curved state by the negative pressure.

6. The method as claimed in claim 5 , wherein at least one of:

a. in a first step, the elastic membrane is brought up to the surface by the automated system,

b. in a second step, the negative pressure is applied in the region between the surface to be provided with the adhesive film and the membrane,

c. in a third step, the membrane is transformed into the curved state with the convex and concave sides by the applied negative pressure, and

d. a curvature of the membrane is intensified by the negative pressure until the adhesive layer of the adhesive film is pressed onto the surface over the entire surface area of the adhesive layer by the convex side of the membrane.

7. The method as claimed in claim 5 , wherein if the pressure exerted by the membrane on the surface to be provided with the adhesive film increases, the negative pressure is increased.

8. The method as claimed in claim 1 , wherein at least one of:

a. the membrane consists of an elastic polymer material,

b. the membrane has a uniform thickness, and

c. the membrane has weakening and/or reinforcing regions for targeted influencing of the geometry of the curved state.

9. The method as claimed in claim 1 , wherein at least one of:

a. the membrane is transformed into the curved state by a positive pressure, and

b. the membrane is heated or cooled before the adhesive film is pressed on.

10. The method as claimed in claim 1 , wherein at least one of:

the adhesive film is positioned between the surface and the elastic membrane by a mounting film to which the adhesive film adheres with its side that faces away from the adhesive layer, and at least one of:

a. to position the adhesive film, the mounting film is fixed on or in a frame, and

b. after the adhesive film has been pressed onto the surface, the mounting film is pulled off from the adhesive film.