Body structure of a passenger car and especially of a convertible

A body structure of a passenger car, and especially of a convertible, features at least one side door on each longitudinal side of the vehicle. The side door, when closed, connects to adjoining fixed pillars via hinges at one end and via a lock assembly at the other end. For improved crash resistance of the body structure of a passenger car, and especially of a convertible, with a rear engine in the event of a head-on collision, a buttress assembly is installed between the rearward rim of the side door and the adjoining lock-side pillar. The buttress assembly effectively holds the side door in its closed position in the event of a head-on collision, while at approximately the level of the buttress assembly, the side door is braced by a hollow strut that extends in the longitudinal direction of the vehicle.

This application claims the priority of German application 10 2004 018 745.2, filed Apr. 17, 2004, the disclosure of which is expressly incorporated by reference herein.

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates to the body structure of a passenger car and especially of a convertible.

Conventional body structures of passenger cars and especially of convertibles pose a problem in that in the event of a head-on collision, the front and/or rear section of the body shifts in the longitudinal direction of the vehicle, causing the rearward rim of at least one side door to strike the pillar next to the door-lock side.

Due to the die-release camber of the stamped sheet-steel parts constituting the door and the pillar, the side door, when striking the lock-side pillar, tends to bend and slide outward without absorbing any impact energy. Especially in the case of a convertible with a rear engine, the weight of that rear engine causes the aft section of the vehicle to shift forward and the side door to slip out as described above.

It is an object of this invention to introduce provisions in the structural configuration of a passenger car, with emphasis on a convertible equipped with a rear engine, that improve the crash-resistance performance of the body structure in the event of a head-on collision.

According to the invention, this object is achieved with the claimed design features. Additional, advantageous enhancements of the invention are defined by dependent claims.

Primary improvements achieved with the invention include bracing of the side door and interpositioning of a buttress assembly between the rearward rim of the side door or doors and the adjoining pillar. The buttress assembly provides effective support in the case of a head-on collision and significantly improves the crash resistance of the vehicle body, since even in a head-on collision the side door remains in its closed position while also transferring impact energy in the longitudinal direction of the vehicle. In a head-on collision of a convertible with a rear engine, the lock-side pillar will transfer the impact energy through the side door into the hinge-side pillar.

After a head-on collision, the side door can still be opened without difficulty. The effectiveness of the buttress assembly and bracing increases with the height at which the buttress assembly and the bracing are installed (large upward lever arm). Both features are preferably positioned next to the ‘equator’ of the passenger car, reliably preventing the side door from popping open in the event of a head-on collision.

The buttress assembly is provided on both the side door and the adjoining lock-side pillar, at a right angle to a vertical plane of the longitudinal vehicle center, with butt plates which face each other at a distance and which in the event of a head-on collision impacting the vehicle body come in contact with one another. The butt plate mounted on the fixed pillar preferably is a separate buffer element that can be attached to the pillar. The buffer element is preferably a tetrahedral forged-steel component, mounted on the pillar with the interpositioning of a seal.

The opposite buffer element on the door is composed of a wedge-shaped compensating element and a partial section of a projecting trough-shaped cover plate. The wedge-shaped compensating element is simply attached to the cover plate by means of a double-sided adhesive strip, constituting a prefabricated easy-to-mount component. That component can be installed through an opening provided in the door and can be clipped onto the rim of the opening. It is also possible to integrate the two buffer elements, in unitized fashion, into the door and the fixed pillar, respectively.

The hollow strut connects at one end to the forward hinge reinforcement and at its other end to the lock reinforcement of the door. The hollow strut consists of a tubular element or of a top-hat-contoured partial channel section of the outer door-well reinforcement capped with a hat-shaped edge plate.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1depicts a passenger car1, i.e. a convertible with a body2featuring above its equator3a convertible top4. The body2encompasses a front section5, an aft section6containing a rear engine, not illustrated, and, on each longitudinal side of the vehicle next to the passenger seat well7, at least one side door8which, when in its closed position A, connects to adjoining pillars10,11via hinges, not shown, at one end and via a lock system9at the other end.

In the example shown, the hinge-side pillar10is in the form of an A-pillar and the lock-side pillar11is in the form of a center or B-pillar. Each longitudinal side of the vehicle may also be provided with two or more side doors8.

Each side door8includes a door body12that extends roughly to the equator3, and a vertically adjustable door window13. The door body12is composed of an outer shell14and an inner door frame15. Within the door body12, the hinge area is provided with a hinge reinforcement16and the area of the lock system9is provided with a lock reinforcement17.

Next to the equator3of the passenger car1the door body12is provided with an inner door-well reinforcement, not illustrated, as well as an outer door-well reinforcement18. In the example shown, the side door8and the adjoining pillars10,11consist of several interconnected sheet-steel components.

Viewed from the top, the rearward rim19of the door8and the front face section20of the adjoining fixed pillar11extend from the inside in front to the outside in back.

Between the rearward rim19of the minimum of one side door8and the adjoining lock-side pillar11a buttress assembly21, locally effective in the event of a head-on collision, holds the side door8in its closed position A. Moreover, the side door8is braced, at about the level of the buttress assembly21, by means of a hollow strut22that extends in the longitudinal direction of the vehicle.

The buttress assembly21and the hollow strut22are positioned as high as possible on the body2, i.e. preferably close to the equator3of the passenger car1. As shown inFIG. 6, the buttress assembly21is provided, both on the side door8and on the adjoining pillar11, with buffer elements23,24that are mounted at a distance from each other and at a right angle to a vertical plane B-B extending in the longitudinal center of the vehicle, and strike each other in the event of a head-on collision that impacts the body2. In the closed position A of the side door8the two buffer elements23,24are spaced apart far enough in the longitudinal direction that the side door8can be easily opened (distance C). The buffer element23associated with the pillar11is mounted on a separate support block25that can be attached to the pillar11.

The support block25preferably consists of a forged-steel element which in the implementation example shown is roughly tetrahedral. For the proper alignment of the support block25on the pillar11the bottom surface26of the support block25is provided with an alignment pin27that engages in a matching hole28in the pillar11. In the bottom surface26of the support block25, next to a continuous peripheral ridge29, a recess is designed to accommodate a flat gasket30.

The gasket30is glued into the recess. The support block25is preferably attached to the pillar11by means of a detachable screw connection31. To that effect the fixed pillar11is provided with a socket element33featuring a female thread32that accepts a mounting screw34for locking the support block25in place. In the support block25a stepped cylindrical bore36accepts the mounting screw34. The cylindrical bore36essentially extends at a right angle to the bottom surface26. The head37of the mounting screw34is concealed by a cap38that snaps into the bore36.

In the example shown, the door-side buffer element24is composed of a wedge-shaped compensating element39and a partial section40of a projecting trough-shaped cover plate41. The wedge-shaped compensating element39is a cast-metal component, pre-mounted on the trough-shaped cover plate41by means of a double-sided adhesive strip. Both components are installed in the door8through an opening42provided in the rearward end face of the door8. The rim of the cover plate41is attached to the opening42by means of clip-on connectors. When installed, another double-sided adhesive strip is positioned between the surface of the compensating element facing away from the cover plate41and the front end of the hollow strut22. In cases where the side door8and/or the adjoining lock-side pillar11are cast-metal components, at least one of the two buffer elements23,24could conceivably be integrated in unitized fashion into the door8or the pillar11.

One end of the hollow strut22connects to the forward hinge reinforcement16, its other end to the lock reinforcement17of the door frame15, thus forming a frame-like composite structure. In the example shown, the hollow strut22is made up of a partial, hat-shaped channel section44of the outer door-well reinforcement18topped by a hat-shaped edge plate45, with the door-well reinforcement18and the edge plate45firmly connected on parallel flanges by a welding, cementing or similar process.

The hollow strut22could alternatively be in the form of an essentially horizontally aligned tube (not shown) extending in the longitudinal direction of the vehicle and being so dimensioned that in the longitudinal direction of the vehicle it can transfer strong forces without buckling.