GB2462375A

GB2462375A - A method of producing a motor-vehicle body

Info

Publication number: GB2462375A
Application number: GB0913747A
Authority: GB
Inventors: Karl Schoenbauer; Klaus Polifka
Original assignee: Bayerische Motoren Werke AG
Current assignee: Bayerische Motoren Werke AG
Priority date: 2008-08-07
Filing date: 2009-08-06
Publication date: 2010-02-10
Anticipated expiration: 2029-08-06
Also published as: DE102008036893B4; GB0913747D0; GB2462375B; DE102008036893A1

Abstract

A motor vehicle comprises a basic part and a superstructure. The basic part comprises e.g. a convertible or similar vehicle. A superstructure can be fastened to the basic vehicle and result, depending on its shape, in a saloon, a coupe, a convertible with a roll bar or a multi-purpose vehicle. The aim of the present invention is to provide a simple method of producing a motor-vehicle body. The method according to the present invention for producing a motor-vehicle body with a fixed roof comprising the following three steps: producing a space frame, also including a roof side frame 7, producing a pre-assembly group 12 comprising at least a roof skin 13 and the visible skin plates 14, 15, which surround an opening for a rear window, and joining the pre-assembly group 12 to the space frame. Optionally the preassembly group 12 includes the rear wing, and the group 12 may be welded together.

Description

A niethod of producing a motor-vehicle body The present invention relates to a method of producing a motor-vehicle body.

DE 195 48 997 Cl proposes a motor vehicle comprising a basic vehicle and a superstructure. The basic vehicle is for example a convertible or similar vehicle. If a superstructure is fastened to the basic vehicle the result, depending on the shape of the superstructure, will be a saloon, a coupé, a convertible with roll bar or a multi-purpose vehicle.

An aim of the present invention is to provide a simple method of producing a vehicle body.

This aim is addressed by a method of producing a vehicle body and having the features of the present invention.

Accordingly the present invention is directed to a method of producing a motor vehicle body with a fixed roof comprising at least the following steps: (a) producing a space frame, also including a roof side frame, (b) producing a Pre-assernbly group comprising at least a roof skin and visible skin plates, which surround an opening for a rear window, and (c) joining the pre-assernbly group to the space frame.

The visible skin plates surrounding the opening for the rear window usually comprise a skin plate under the opening and a skin plate in the neighbourhood of each column laterally bounding the opening. Preferably the pre-assembly group also includes the rear wing. Advantageously all the skin plates of the pre-asserubly group are welded together.

By means of the method according to the invention, the skin plates can be welded together without difficulty, since the welds are all easily accessible. The skin plates can be spot-welded, not necessarily in an inert gas atmosphere. If on the other hand the skin plates were fastened to the space frame before welding, some welds between the skin plates would be accessible only with difficulty if at all. The method according to the invention thus simplifies production of the body and reduces labour, costs and/or the required investment.

In a preferred embodiment when the pre-assembly group is fitted on to the space frame, the front end region of the xoof skin is screwed to a top apron of the space frame, bounding the top of an opening for a front window.

Advantageously after the screwing operation, an ornamental cover is fastened over the screws so that the screws are not visible from the exterior.

Preferably the space frame has holders for screwing the pre-assembly group.

In a preferred embodiment the pre-assembly group has holders for screwing to the space frame.

Advantageously when the pre-assembly group is attached to the space frame, the holders are screwed to the recesses.

Preferably the holders and/or recesses are designed so that tolerances during the screwing process can be compensated in at least one direction.

An example of the method according to the present invention will now be described hereinbelow with reference to the accompanying drawing, in which: Figure 1 shows an exploded perspective view of a passenger-car body.

Figure 1 shows a space frame 1 of a coupé body. The space frame 1 comprises a front structure 2, a passenger compartment 3 and a rear structure 4. The front wings 5 are already fastened to the front structure 2 illustrated. The passenger compartment 3 is bounded on each side by a sillboard 6 on the bottom edge and a roof side frame 7 on top. The roof side frames 7 each extend backwards from a top end region of an A-column 8 and also form a C-column 9. The both frames 7 are connected together by a number of transverse hoops 10. In addition the two top ends of the A-columns 8 are connected together by a top apron 11 in the transverse direction of the vehicle. The top apron 11 also forms the top boundary of the opening for the front window. The roof side frames 7, together with the hoops 10 and the top apron 11, form the structure supporting the roof.

A pre-assembly group 12 is shown offset from the space frame 1. The pre-assembly group 12 comprises a roof skin 13, the skin plates 14 in the neighbourhood of the C-columns 9, the skin plate 15 under the opening for the rear window, and the rear wings 16. All these skin plates 13, 14, 15 and 16 have been welded to the pre-assembly group 12.

In the assembly process, the pre-assembly group 12 is bent over the top of the space frame 1 and fastened thereto. To this end the front edge region of the skin plate 13, viewed in the direction of motion of the coupé, is screwed to the top apron 11. To prevent the screws being visible from the exterior, after the screwing operation an ornamental cover is fastened over the screws, covering them completely and forming the visible skin. All other fastenings of the pre-assembly group 12 to the space frame 1 are constructed as follows: The space frame 1 has recesses for screwing the pre-assembly group 12. To this end holders are mounted on the pre-assembly group 12 for screwing to the recesses. when the pre-assembly group 12 is joined to the space frame 1, the holders are screwed to the recesses. The holders and/or recesses are designed so that the tolerances during screwing can be compensated in at least one direction. To this end, for example, the holders and/or the recesses can be slotted. The holders are fastened to the pre-assernbly group 12 so that neither the holders nor the means attaching them to the pre-assembly group are visible from the exterior. For example an edge region of a skin part of the pre-assembly group 12 can be beaded or flanged on the inside. During the beading process, a holder can be incorporated in the flange.

It is proposed in the prior art to mount a roof on a basic vehicle. The general idea, however, is to use a basic vehicle for vehicles of different constructions. The basic vehicle thus corresponds roughly to a convertible. However a convertible with an attached roof is unlikely to be given the stiffness of the body according to the invention, which is based on a complete space frame 1 including all load-bearing parts 7, 10, 11 of the roof. According to the invention the mounted pre-assembly group 12 comprises only the skin components 13, 14, 15, 16, not of the complete roof. This assembly sequence enables the skin parts to be welded together in simple manner without reducing the stiffness of the body.

Claims

Claims 1. A method of producing a motor-vehicle body having a fixed roof, comprising at least the following steps: (a) producing a space frame, also including a roof side frame, (b) producing a pre-assembly group comprising at least a roof skin and visible skin plates, which surround an opening for a rear window, and (C) joining the pre-assembly group to the space frame.
2. A method according to claim 1, in which the pre-assembly group includes the rear wing.
3. A method according to claim 1 or claim 2, in which all the skin plates of the pre-assembly group are welded together.
4. A method according to any preceding claim, in which when the pre-assembly group is fitted on to the space frame, the front end region of the roof skin is screwed to a top apron of the space frame, bounding the top of an opening for a front window.
5. A method according to claim 4, in which after the screwing operation, an ornamental cover is fastened over the screws so that the screws are not visible from the exterior.
6. A method according to any preceding claim, in which the space frame has holders for screwing the pre-assembly group.
7. A method according to any preceding claim, in which the pre-assembly group has holders for screwing to the space frame.
8. A method according to claim 6 or claim 7, in which when the pre-assembly group is attached to the space frame, the holders are screwed to the recesses.
9. A method according to claim 8, in which the holders and/or recesses are designed so that tolerances during the screwing process can be compensated in at least one direction.
10. A method of producing a motor-vehicle body substantially as described herein with reference to the drawing.