The present day manufacture of vehicles, particularly cars, is to a great extent based on the construction of bodies by welding together plates and panels into a unit with a structure which has the necessary strength and rigidity, permitting the body to be assembled together with a chassis, with springs and wheel suspension and with installation of the engine and other parts. This construction method constitutes a substantial advance over the original vehicle construction, which consisted of a strong frame, where panels and body parts were mounted on the frame.

The development has largely been based on the utilization of steel, with plates which are stamped out as panels and welded together on highly rational and effective, robotized assembly lines. This production method is therefore highly advanced with regard to control and precision, with associated very high investments. A production method of this kind will therefore be appropriate and financially justifiable in the manufacture of large production volumes.

To-day the trend in further development is towards the building of vehicles and cars which are both smaller and lighter, and which above all should be capable of being driven with a reduction in energy consumption, thereby reducing the strain on the environment. For this purpose modern materials and new production methods are employed. A further feature in this development trend is the production of vehicles or cars which are intended to cover a special requirement or a niche in the market, i. e. they are not intended for universal use, e. g. over long distances. Such"niche"vehicles, which are also regarded as conveyances or means of transport, will not normally satisfy the requirements for manufacture in very large production volumes, and for such vehicles there have therefore been developed special

production methods and materials employed which until now have not been widely used in car production.

In the case of these vehicles too, however, it is very important for the vehicle to offer a sufficiently high degree of safety for the user and it is therefore crucial that in this case too it is possible to incorporate the necessary strength and deformation conditions in the design in order to be able to meet modern safety requirements.

The use of profiles, e. g. in aluminium, has been shown to provide interesting construction methods for future vehicle development through so-called "space frames". These frames are built up by joining the profiles together by means of welding, gluing or by other mechanical attachment means. Such a frame, e. g. in aluminium, is light in weight and can be calculated and dimensioned to provide a very high level of safety. In order to be able to construct a final vehicle, panels and body parts have to continue to be built together on this frame. For this purpose metal, possibly aluminium panels or plastic panels may be used which are mounted on the frame by substantially known means. Even though this may indicate a step backwards towards conventional construction technology, where frames were employed, the only difference being that modern materials such as aluminium and plastic are used, while at the same time greater safety is built into the frame, a construction method of this kind will also be of very great interest for the above-mentioned new vehicle types. One of the reasons for this is that considerably lower investments are required in order to be able to develop a vehicle on this basis. At present the method is most suited to smaller production numbers.

Supporting frames of this kind can also relatively simply be built in a steel structure where a simple surface treatment then has to be carried out for corrosion protection. This treatment is substantially simplified compared to surface treatment of a traditional car body, which subsequently has to be sprayed.

"Space frames"is a term for frames of this kind which are composed of profiles with connection points. These are employed in several types of vehicle and are of considerable interest. A major challenge, however, is to be able to achieve a simplified and rational installation of body parts and panels.

It is known in the prior art to use plastic in body parts in various design variants in combination with an aluminium frame or steel frame. Polyester or epoxy body parts have been most used, but other types of plastic have also been employed, by means of vacuum forming, injection moulding or where panels are produced by means of spraying and fitting.

Examples of such known designs can be found, e. g., in DE 19500361 which discloses a body/frame structure, where the rear frame section and outer roof beams consist of a part, which in turn is attached to a lower floor section.

The outer panel on the rear is in turn attached to the outside of this. In EPO 584576 an outer structure is employed which forms the actual cabin, on which is mounted a front module, these parts being glued together. A similar design, based on a complete cabin, is also described in EPO 547583.

In EP Patent 485457 and 697974 methods are described as to how a metal frame can be used in combination with large body parts which in a simple design can form the whole body.

The object of the present invention is to provide a new form of assembly for a vehicle, where the vehicle body can be manufactured from large plastic units, preferably thermoplastic and specially preferred coloured thermoplastic, where the body parts can also be made in smaller production series and where these can be mounted in a simple and rapid manner on a vehicle frame structure, e. g. of aluminium, without the use of complicated aids.

This object is achieved according to the invention with a device of the type mentioned in the introduction, which is characterized by the features presented in the patent claims. The invention also comprises a method for manufacturing a vehicle of this kind, which method is characterized by the features presented in patent claim 13.

The invention differs from the previously known designs, representing a highly simplified design. The problems with the previously known designs are that it is a long-winded and difficult process to mount solid cast bodies or large parts of the body, since these are difficult to integrate and mount in a prefabricated framed structure.

In some cases there is a need to divide the framed structure in order to be capable of installing the large body elements. This not only results in an extra work operation with the frame assembly, but also often means an impairment of the framed structure and costly steps in order to ensure a simplified mounting and a satisfactory degree of safety. For example, the design according to DE 19500361 requires welded-on and integrated metal plates in the framed structure, since the body panels only give the vehicle the external shape and appearance without a closely connected body module.

In the present invention the wish is to unite style and external appearance to a greater extent with utility and functional solutions by a combination of a metal frame and plastic panels. This is done in a manner whereby the plastic body part has more integrated functions than simply being a cover with exterior and visual advantages. In addition, a construction method is employed where the plastic body parts include functions such as sealing and separation of the vehicle's interior and exterior environment, and the parts may include elements such as wheel arches, mudguards, etc., inset lights, sealing edges, etc.

A special feature of the invention is also that moulding methods and materials can be used for production of the body parts which eliminate the need for painting of the body parts. Painting is an undesirable operation on account of environmental conditions and costs.

In a special embodiment of the invention the front and rear vehicle body parts are designed to overlap, resulting in a reinforced central part in the vehicle. This provides a further reinforcement and separation between the external and internal environments, which can be advantageous in special applications.

The invention will now be explained in more detail by means of embodiments which are illustrated in the drawings, in which: figure 1 is a completely schematic view illustrating the design of the device according to the invention, with the parts separated from one another, figure 2 is a second embodiment of the invention, viewed in a schematic horizontal section,

figure 3 is an embodiment corresponding to figure 2 in a lateral sectional view, in connection with a cabriolet design, and figure 4 is a side view of the cabriolet design in figure 3.

As mentioned above, the drawings are purely schematic representations, which are only intended to illustrate the principal design of the device according to the invention and the method for manufacture thereof. In the drawings only those elements are included with are necessary for illustrating the inventive concept, since the other features can be varied and will be a technique which can be implemented without difficulty by a person skilled in the art.

Figure 1 illustrates the principle of the device according to the invention, some of the body parts having been pulled out to the side, while the final assembled shape is illustrated by means of broken lines.

The basic element in the design is a metallic frame, e. g. a frame of the"space frame"type, which is designated 1 and on which the necessary mechanical components and systems are mounted in a simple and rational manner. The frame is open with easy access. The vehicle can therefore be constructed with chassis systems in the front and rear, an engine and other technical connections without any hindrance from closed areas in the frame.

Depending on the transmission system, i. e. whether the engine is installed at the front or the rear, possibly electrically powered, requiring room for placing batteries, the floor system 2 can be made flexible, thus making room for these said transmission systems under the vehicle, e. g. in the area designated 3. The floor system is designated 2.

A floor 2 can therefore be attached to the frame, e. g. on two levels in order to provide space and opportunity for mounting batteries under the vehicle in the area at 3. In a design of this kind attempts will be made to lay the high floor level under the seats 4.

The vehicle's upwardly projecting pillars, which are designated A and B pillars, and given the reference numerals 5 and 6, are also mounted on the frame, together with a roof frame 7 for closed vehicles. The upwardly projecting pillars are preferably approximately vertically arranged, but may also assume angled or curved shapes, according to the body design.

The body is mainly composed of a rear part 8, which constitutes a large body part comprising both the rear sides, wheel arches and mudguards and floor section which is then attached to the vehicle's B pillars 6, possibly also other points. In cases where the vehicle has 4 doors, this part 8 may be attached to the vehicle's so-called C pillars, and the B pillar thereby becomes a middle pillar. The front part 9 of the vehicle is designed as a cover which is open below, thus enabling it to be laid over the engine and wheels and attached in the area around the vehicle's A pillars 5. In the inside it is expedient to construct a separate torpedo wall from the pedal set up to the dashboard in order to close and seal the internal cabin. This cover 12 may also be an extended part of the plate in the floor. A loose roof 10 may be attached to the frame over the window, and doors installed on the A and B pillars 5 and 6 respectively, possibly by using 3 pillars on each side, between the pillars.

In figures 2-4 there is illustrated a second embodiment of the invention, where the rear and front parts 8 and 9 overlap each other. The rear body part 8 is thereby designed with the external form and the external measurements required by the vehicle up to the area at the rear pillar or the B pillar 6, while the vehicle's front body part 9 extends backwards with the external dimensions and design of the vehicle in the area up to the A pillars 5. In this embodiment the front part of the rear body part 8 is extended forwards on the inside of the pillars 5 and 6, to the front area of the cabin's interior, where it forms an upwardly projecting or extending wall 11 between the cabin's internal compartment and the external technical compartment or motor compartment, where it can be terminated with an attachment or a seal against the lower window frame 13. In the same way, this part may include the vehicle's dashboard or the basic part of the dashboard 12, as illustrated in figure 3.

By employing a suitable plastic material and moulding technology, a bumper cover can be moulded into the front part 9, together with other details such as a grille, a recess and securing means for lights, etc.

The doors are installed as a subsequent part of the assembly process and are attached on the front pillar 5 and locked in a closed state against the pillar 6.

An important feature of this design is that the split line between the door and rear body part can be adjusted in a simple manner by adjusting or shifting the hinge point for the door on the pillar 5. The front part can then be adjusted

towards a front door line, with the result that it is in perfect alignment with the door split.

When 3 pillars are used, i. e. A, B and C pillars, the procedure will be the same, also when mounting the rear door. In figure 1 a device is illustrated for a vehicle with a roof structure. Figure 4 illustrates that the same vehicle device can also be employed with a design without a roof.

The invention represents a highly rational and effective method of constructing a vehicle. The body parts, both front and rear, i. e. 9 and 8 are mounted after all the mechanical components, chassis, springs, engine, etc. have been installed on the open frame. These can be made of different types of plastic by means of different production methods which offer the possibility of constructing three-dimensional large parts. An example of such a part is a rotationally moulded part and vacuum forming and blowing may also be employed in the case of given design criteria. A preferred material is thermoplastic and particularly coloured thermoplastic, but other plastic materials with similar properties may also be used.

The assembly of the plastic body parts and the metal structure offer the possibility of providing a good seal since there are no more body panels which have to be joined together and sealed. The plastic edges may be pushed in and locked to the metal structure, e. g. by means of clamping.

Despite the fact that these relatively large body parts do not provide any structural strength in the structure, they have an obvious functional effect in arriving at a complete vehicle.

The invention is described in purely schematic terms and the fact is referred to, e. g., that 3 pillars may also be used on each side instead of 2. The device can be varied in many ways within the framework of the claims while retaining the main features, viz. the use of a large construction part as the front part and a large construction part as the rear part, these construction parts being in three-dimensional form, which gives them great strength and rigidity, thereby providing a safe body. It will be possible to vary the actual design and form.