Plastic Body Arrangement for Small, Light Vehicles

1. Field of the Invention

The present invention relates to an arrangement of and a method for the production of bodies/cabins for lightweight vehicles, by which the bodies/cabins are moulded/casted/blow moulded, mainly with floor, sidewall and roof in one piece, by means of floating/spot-free devices for securing/fixing the cabin to the vehicle's roll-over safety bars and floor frame/chassis.

2. Description of Related Art

For the building of car bodies/cabins, it has been normal to use a metal frame with plates welded on as bodywork. This is possible when the plates and the framework are both metallic. Building bodies/cabins with glass-fibre reinforced Polyester has been tried, but it proves to be extremely work-intensive. It necessitates a substantial amount of handwork, being built up in layers and thus making the bodies expensive. In addition, the fixing between a metal framework and the plastic bodyparts by screws or rivets creates local stresses.

Metal bodies have therefore more or less controlled the market, but these are heavy and have disadvantages such as corrosion and the like. Comprehensive galvanization and paint treatment have been necessary, but the problems still exist. Another drawback is that the bodies are getting very heavy, which has impeded the development of small, lightweight vehicles.

The object of the invention is to make it possible to produce small, light vehicles, without the above mentioned disadvantages.

This is achieved by an arrangement by such vehicles and a method for producing such vehicles as described in the claims.

FIG. 1 is a cross-sectional view, taken along lines 1--1 of FIG. 2, of a small light vehicle according to an embodiment of the present invention;

FIG. 2 is a side view of a small, light vehicle according to an embodiment of the present invention.

This invention has made it possible to produce the car/vehicle body/cabin by, for example vacuum moulding, blow moulding and rotational moulding, mainly with floor, roof and sidewalls in one piece. In the case of rotational moulding, four moulds and a cycle of 1 hour is used, the moulding time for each body will be approximately 15 minutes. By using coloured plastics, no further surface handling is needed, and if the body suffers a blow, it will sustain few visible "scratches" or dents. The elastic plastic material will also be more gentle on the passengers in case of a crash.

According to the invention, in the production mould, recesses are made from the outside to the inside for doors and windows. The recesses terminate at their innermost point in an approximately 90.degree. angle, and the openings are cut out so that a projection remains. Cut-outs are made for windows and doors after the body has been moulded.

To make the body lightweight and as safe as possible, it is assumed according to the invention, that one uses internal roll-over safety bars and a metallic floor frame/chassis, preferably of aluminium. Plastic and aluminium have different degrees of temperature expansion, and according to the invention the body is fixed in a flexible manner to the rollover bars that are secured to the floor frame/chassis.

At least two of the roll-over bars are fastened to the floor frame, one on each side of the door opening, and they are covered by the body's/cabin's plastic on at least two sides.

Profiles envelope and fix the rest of the plastic angle after the opening for doors/windows have been cut out; they direct and press the plastic against the roll-over bars when the profile is firmly fixed; screwed or riveted. This also provides a stable flange for doors and windows. This allows the plastic and the metal framework to move in various ways in varying temperatures. Fatigue fractures will therefore not arise at local fixing spots.

According to the invention the above mentioned profiles are also used to secure the weatherstrip/gaskets around the doors and windows. It is assumed that these opening shall not have sharp-angled corners, but preferably rounded ones with a radius of 20 mm or more. The profiles are, according to the invention, also intended to cover the plastic edges resulting from the cutting out of openings for doors and windows.

As mentioned above, the invention is intended to be used for light-weight bodies/cabins and it assumes therefore that the side door is combined with the window. Preferably, the whole door should be made of an impact-resistant, transparent plastic.

The internal roll-over safety bars curve toward the ceiling and have a greater radius than that of the adjacent part of the plastic body/cabin. This means that it allows for varying expansions and shrinkage of the plastic and metal parts when temperatures change.

The invention can be produced in various ways, and FIG. 1 shows one means of production, where A shows the body/cabin part with a recessed are K for the door opening. B shows the cut out door opening, with the cut edge forming an end projection D a slight distance from an angular portion K innermost in the recessed area. A profile C envelopes the remaining end of the angular portion K and the end protection D, and fastens the body/cabin A floatingly to the roll-over bars/framework E, which can be round or square. The profile C can be fixed to the roll-over bars/framework E by e.g. means of screws or rivets. The profile C has an extention on the side of the door and window intended for hinges G, for fastening the hinges. The profile C is also used to fasten a weatherstrip/gasket F around the door and windows. The windscreen L can likewise overlap the roll-over bars/framework E at the back and is secured by the profile C.