Motor vehicle body side wall

A body side wall for motor vehicles, in particular for passenger cars and station wagons, which includes a rear side door opening and a rear pillar formed adjacent the vehicle rear wheel opening from inner and outer panels of the side wall together with a reinforcement panel. The invention wall construction includes a one-piece reinforcement panel which is formed in a U-shape and is positioned adjacent the door opening extending from the roof frame along the rear pillar and the front part of the wheel housing, the reinforcement panel being connected to the side wall inner panel and the side wall outer panel to form a box support extending from the roof frame to the sill.

BACKGROUND OF THE INVENTION 1. Field of Invention 
The invention relates generally to body side walls for motor vehicles and 
more particularly to the parts of body side walls of passenger cars and 
station wagons in the area of the rear side door opening. 
2. Description of the Prior Art 
A body side wall for motor vehicles of this type is known from the German 
Laid-Open Specification No. 24 28 477, in which a rear pillar is formed as 
a box support by joining a side wall inner panel and a side wall outer 
panel with an angular reinforcement panel. This box support is positioned 
adjacent to the front part of the wheel housing and is adapted to be 
connected to the longitudinal support of the body below the door entrance. 
The specification provides, however, no further details on the upper shape 
of the rear pillar or the front connection of the box support. 
Another body side wall for motor vehicles is known from the German 
Published Specification No. 24 32 238, in which a U-shaped profiled 
reinforcement panel extends from the rear transverse support of the 
vehicle roof along the upper edge of the side wall inner panel and is then 
bent downwardly toward the rear part of the wheel housing and is welded 
essentially over its entire length to the side wall inner panel to form a 
box support. This arrangement of a reinforcement panel is intended to 
increase the energy absorption of the body structure in the event of a 
rear collision. 
Another body side wall for motor vehicles is known from the German Pat. No. 
29 31 467, in which a reinforcement panel, which is formed in a U-shape 
and which is supported at its lower end on the arch of the wheel housing, 
is disposed between a side wall inner panel forming a rear pillar and a 
side wall outer panel. An improved transverse rigidity of the bodywork is 
to be achieved by virtue of this reinforcement panel. 
In the case of the last two known body side walls, the strength arising 
from the chosen design in the region of the rear side door opening is not 
substantially considered, since the designs are intended for motor 
vehicles in which a considerable rear body overhang makes an adequate 
strain path available in the event of a rear collision. 
SUMMARY OF THE INVENTION 
The object of the invention is to increase the strength arising from the 
chosen design in the region of the rear side door opening of a motor 
vehicle in which a rear pillar is formed as a box support by joining an 
inner and outer body panel through a reinforcement panel by providing a 
single reinforcement panel in such a way that in the event of a rear 
collision, despite a short rear overhang, the area of the body adjacent 
the rear side door opening does not undergo deformations which would 
adversely affect the opening of the vehicle door after the collision. 
This object is attained according to the invention in that a one-piece 
reinforcement panel is provided which is formed in a U-shaped 
cross-section. It is positioned adjacent the door opening and extends from 
the vehicle roof along the door opening and extends from the vehicle roof 
along the rear pillar and the front of the wheel housing to the door sill, 
being connected to inner and outer side wall panels to form a continuous 
box support. 
By virtue of the fact that a reinforcement panel, which is formed in a 
U-shape and is adjacent to the door opening starting from the roof frame 
and extending by way of the rear pillar and the front part of the wheel 
housing, is connected to the side wall inner panel and the side wall outer 
panel while forming a continuous box support extending from the roof frame 
to the sill, the chosen design produces strength in the region of the door 
opening such as cannot otherwise be achieved or can be achieved only with 
a substantial outlay in terms of weight with known box supports comprising 
partial reinforcement panels. 
By virtue of the fact that in the region of the rear pillar the one-piece 
reinforcement panel together with the side wall outer panel and the side 
wall inner panel forms a box support comprising a diagonal web, a very 
strong and compact rear pillar is provided. 
By virtue of the fact that in the region of the front part of the wheel 
housing the one-piece reinforcement panel together with the side wall 
outer panel forms two box supports extending in parallel fashion, a 
strength arising from the chosen design which substantially avoids a 
deformation of the door opening as the result of an accident, is achieved 
in this curved region of the vehicle body.

DESCRIPTION OF A PREFERRED EMBODIMENT 
As shown in FIG. 1, a body side wall for a motor vehicle essentially 
comprises a side wall outer panel 1, a side wall inner panel 2, a wheel 
housing 3 and a U-shaped profiled one-piece reinforcement panel 4. 
As shown in FIGS. 2 and 5, the upper part of the one-piece reinforcement 
panel 4 has a U-shaped cross-section 5 which is open toward the outside 
and which has angled welded flanges. In its lower part adjacent to the 
wheel housing 3 the one-piece reinforcement panel 4 comprises, as may best 
be seen in FIG. 6, two U-shaped cross-sections 6 which extend in parallel 
fashion and which in the connection area of the sill pass into a 
horizontal portion with a V-shaped cross-section 7 and angled welded 
flanges, as may best be seen in FIG. 7. 
As shown in FIG. 3, the wheel housing 3 comprises only one inner wheel 
housing panel of conventional shape. 
In FIG. 4, there is shown the shape of the side wall inner panel 2. In one 
region identified by the numeral 8, it forms part of the rear pillar. In 
this region 8, the inner panel 2 is made relatively level and flat in 
order to close a corresponding portion 9 of the side wall outer panel 1 
which is formed in a U-shape, as may best be seen in FIG. 5. In this same 
region, the upper part 5 of the reinforcement panel 4, also formed to have 
a U-shaped cross-section, is joined in conventional manner by spot welding 
to this relatively level region 8 by way of flanged panels angled to 
engage the inner panel 2 as is shown in FIG. 5. The side wall outer panel 
1, the side wall inner panel 2, and the reinforcement panel 4 thus form a 
rear pillar with a box-shaped supporting profile reinforced by a diagonal 
web (See FIG. 5). 
As shown in FIG. 4, the level region 8 of the side wall inner panel 2 ends 
at the wheel housing 3, and the part of the reinforcement panel 4 having 
the two U-shaped cross sections 6 extending in parallel fashion is joined 
to the side wall outer panel 1 through corresponding flange areas by spot 
welding or through adhesion areas as indicated at 10 provided in the area 
between the outer panel and the reinforcement panel 4 (See FIG. 6). 
Turning next to FIG. 7, the side wall outer panel 1 forms, together with a 
lower part of the reinforcement panel 4 having the V-shaped cross-section 
7, a box support which extends into the region of the sill in a curved 
manner and extends a certain further distance in a direction parallel to a 
longitudinal side panel 11 of the floor pan structure of the body. 
Turning finally to FIG. 8, in the region of the belt line of the body, both 
the side wall inner panel 2 and the side wall outer panel 1 are 
simultaneously connected to the reinforcement panel 4 by spot welding. 
While only one embodiment of the invention vehicle side wall construction 
has been described, others may be possible without departing from the 
scope of the appended claims.