GB1573631A

GB1573631A - Vehicle wall having an outer skin coating and method of applying same

Info

Publication number: GB1573631A
Application number: GB1345/77A
Authority: GB
Original assignee: Dr Ing HCF Porsche AG
Current assignee: Dr Ing HCF Porsche AG
Priority date: 1976-01-14
Filing date: 1977-01-13
Publication date: 1980-08-28
Also published as: JPS5288925A; DE2601186B2; DE2601186A1; FR2338315A1; SE7700305L; IT1064455B; FR2338315B1

Description

(54) A VEHICLE WALL HAVING AN OUTER SKIN COATING AND METHOD OF APPLYING SAME (71) We, DR. ING. h.c.F. PORSCHE AKTIENGESELLSCHAFT, of Porschestrasse 42, Stuttgart-Zuffenhausen, Germany, a German Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a vehicle wall having an outer skin or surface coating and method of applying same.

A number of efforts have been contemplated in the industry to construct motor vehicle superstructures for optimum production techniques, ease of repair, and low sensitivity against environmental influences, as well as to protect the outer skin from minor damage.

In all cases, the individual measures taken have had inadequate and insufficient effect.

Also, the present production techniques, partly depending on the prejudice of the technical world and, as a result, also the buyer, refrain from an optimization of the body or superstructure.

For the outer surfaces of motor vehicle bodies, sheet-metal parts with unblemished surface finishes and exact shapes are required, so that the visual outer skin coating, provided by a number of protecting and lacquer layers, exhibits the usual present-day mirror-smooth surface finish. The finishing of the sheet-metal parts is therefore extremely expensive, which is reflected in the price of the vehicles, but this effort is technically not justified. Furthermore, conventional bodywork with a visual outer skin coating are very sensitive to damage by outside force actions, for example, those occurring in parking places through opening of vehicle doors or through stone impacts from passing vehicles because such coatings are extremely hard and brittle.This has a further aggravating disadvantage because, through structural twisting and temperature changes, small hairline cracks occur in the outer skin coating which allow penetration of moisture down to the metal, thereby producing sources of corrosion.

The object of the present invention is to provide a vehicle wall having an outer skin coating by which the described disadvantages are avoided.

The present invention consists in a vehicle wall having an outer skin coating comprising multiple layers applied to the wall and wherein a layer of a synthetic resin having a wavy surface texture of uniform thickness of between 0.4 to 1.2 mm is applied to the outer surface of said wall with one or more primary layers interposed therebetween, said layer of synthetic resin being provided with at least one covering layer.

Such an outer skin coating can be particularly advantageous in that the layer of synthetic resin, by its material characteristics and strength, is not only extensively stone-impact insensitive, but also provides a good protection against corrosion of the metallic vehicle wall surfaces. Expansion and vibration behaviour of these wall surfaces are absorbed without difficulty by the resilient characteristics of the synthetic resinous layer so that flaws and hairline cracks are also avoided. The synthetic resinous layer may be coloured, that is, it can carry a pigment or colouring corresponding to the outside colour of the vehicle. The wavy surface texture which is obtained produces a different, pleasant, aesthetic effect.Finally, such an outer skin coating may be provided during production and assembly for which no close tolerance conditions, for reasons of cost, need to maintained, thereby providing a useful vehicle.

The accompanying drawing illustrates a cross-section through the superstructure wall of a vehicle in an enlarged scale.

In carrying the invention into effect, by way of example, a vehicle body wall 1 illus trated in the Figure, i.e. the outer skin of a vehicle body consists of sheet steel or metal, and is provided at the inner surface A with a basic lacquer 2. The outer surface B of wall 1, which is exposed to the usual and ordinary stresses and weather (climate), stone impact, or the like, is provided with a coating 3 which consists of individual layers 4, 5, 6, wherein layers 4 and 5 are formed, for example, from zinc phosphate, or electro-powder lacquer, which is deposited in micron (,u) thicknesses on the wall 1.

The layer 6 is formed of a synthetic resinous material such as polyvinyl chloride. The thickness C of the layer 6 is between 0.4 to 1.2 mm. This layer 6 is applied in a vacuum or without the presence of air, such as in an inert atmosphere. Naturally, other application processes could be utilized depending on circumstances. Depending upon the degree of fluidity (thick or thin), or viscosity of the layer material, a wavy, nevertheless uniform thickness surface texture 7 results at the outer surface 6 of the layer 3.

The surface texture 7 shown in the Figure has relatively large periodic distances D and E from one wave peak to the next wave peak due to the material being relatively thin.

Additional layers 8, 9 are applied on top of layer 6, which are formed as a cover lacquer 8 and prime lacquer or filler layer 9, each constituted, for example, by alkyd-melamine resins.

WHAT WE CLAIM IS: 1. A vehicle wall having an outer skin coating comprising multiple layers applied to the wall and wherein a layer of a synthetic resin having a wavy surface texture of uniform thickness of between 0.4 to 1.2 mm is applied to the outer surface of said wall with one or more primary layers interposed therebetween, said layer of synthetic resin being provided with at least one covering layer.

2. A vehicle wall according to claim 1, wherein said layer of synthetic resin is a layer of polyvinyl chloride.

3. A vehicle wall according to claim 2, wherein said polyvinyl chloride layer is col oured.

4. A vehicle wall according to any of claims 1 to 3, wherein said covering layer includes a primary lacquer layer and a further cover lacquer layer.

5. A method of providing a vehicle wall having an outer skin coating as claimed in any of the preceding claims, wherein the layer of synthetic resin is applied in a vac ;rum.

6. A method of providing a vehicle wall outer outer skin coating as claimed in 'ktims 1 to 4, wherein the layer of tic resin is applied in an inert atmos 7 vehicle wall having an outer skin coating substantially as described with reference to the accompanYing drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. trated in the Figure, i.e. the outer skin of a vehicle body consists of sheet steel or metal, and is provided at the inner surface A with a basic lacquer 2. The outer surface B of wall 1, which is exposed to the usual and ordinary stresses and weather (climate), stone impact, or the like, is provided with a coating 3 which consists of individual layers 4, 5, 6, wherein layers 4 and 5 are formed, for example, from zinc phosphate, or electro-powder lacquer, which is deposited in micron (,u) thicknesses on the wall 1. The layer 6 is formed of a synthetic resinous material such as polyvinyl chloride. The thickness C of the layer 6 is between 0.4 to 1.2 mm. This layer 6 is applied in a vacuum or without the presence of air, such as in an inert atmosphere. Naturally, other application processes could be utilized depending on circumstances. Depending upon the degree of fluidity (thick or thin), or viscosity of the layer material, a wavy, nevertheless uniform thickness surface texture 7 results at the outer surface 6 of the layer 3. The surface texture 7 shown in the Figure has relatively large periodic distances D and E from one wave peak to the next wave peak due to the material being relatively thin. Additional layers 8, 9 are applied on top of layer 6, which are formed as a cover lacquer 8 and prime lacquer or filler layer 9, each constituted, for example, by alkyd-melamine resins. WHAT WE CLAIM IS:

1. A vehicle wall having an outer skin coating comprising multiple layers applied to the wall and wherein a layer of a synthetic resin having a wavy surface texture of uniform thickness of between 0.4 to 1.2 mm is applied to the outer surface of said wall with one or more primary layers interposed therebetween, said layer of synthetic resin being provided with at least one covering layer.