GB2238989A

GB2238989A - Energy absorbing vehicle door

Info

Publication number: GB2238989A
Application number: GB9025088A
Authority: GB
Inventors: Jeffrey Allen Welch
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1989-12-04
Filing date: 1990-11-19
Publication date: 1991-06-19
Also published as: JPH03200420A; DE4038659A1; CA2031391A1; GB9025088D0

Abstract

A door (10) includes an outer panel (12) and an inner panel (14) which are attached together and define a space (16) therebetween for mounting the window regulator and other door hardware. A door trim panel assembly (24) mounted on the inner panel includes a trim panel (28) of substantially rigid material carrying a decorative trim cover (30) facing the occupant. An energy absorbing collapsible device (26) is interposed between the inner panel and the trim panel for collapsibly absorbing energy imposed thereon. The trim panel (28) has structurally weakened portions, preferably in the form of a plurality of slots (40-46) integrally moulded into the trim panel, by which the trim panel predictably yields to communicate the impact into the energy absorber (26) for absorption. <IMAGE>

Description

-I- ENERGY ABSORBING VEHICLE DOOR This invention relates to a vehicle door

and more particularly provides a substantially rigid trim panel having structurally weakened portions by which the trim panel yields upon impact to communicate energy into an absorbEr concealed behind the trim panel.

It is well known in motor vehicles to provide a decorative door trim panel assembly which overlays the structural inner panel of the vehicle door. Such a door trim panel assembly is typically comprised of a trim panel moulded of a rigid sheet of plastic or hardboard covered with vinyl, cloth or other decorative cover material. The substantially rigid substrate provided by the trim panel serves to effectively mount the trim material on the vehicle door and also rigidifies the structure so that the trim panel will endure the rigors of customer use. The prior art has also recognized that the door trim panel assembly may be comprised of a foam material which collapses and absorbs energy upon imposition of a lateral force thereagainst.

It is also well known to provide an arm rest on the vehicle door and projecting inboard from the trim panel to provide a convenient rest for the occupant's arm. The prior art has also recognized that the arm rest may be comprised of a foam or honeycomb structure which will yield laterally upon imposition of a force thereagainst.

US patent no. 4,783,114 provides an arm rest which overlies a cavity provided in the door trim panel.assembly and which is yieldably mounted for collapse into the cavity upon imposition of a lateral force against the arm rest.

The present invention relates to an improvement in the aforedescribed door trim panel assemblies in which pre- selected areas of the trim panel are structurally weakened so that the trim panel yields upon the imposition of a predetermined impact thereagainst so that the impact energy is communicated through the trim panel and into an energy absorbing structure interposed between the inner panel of the vehicle door and the trim panel.

According to the present invention, a vehicle door includes an outer panel and an inner panel which are attached together and define a space therebetween; and a door trim panel assembly mounted on the inner panel on a side thereof facing away from the outer panel and including a trim panel of substantially rigid material carrying a trim cover, the trim panel having structurally weakened portions, preferably in the form of a plurality of aperture slots integrally moulded into the trim panel, by which the otherwise rigid trim panel predictably yields upon the imposition of an impact of predetermined magnitude thereagainst to absorb energy. An energy absorbing collapsible means may be interposed between the inner panel and the trim panel for collapsibly absorbing energy imposed thereon.

Accordingly, the object of the present invention resides in the provision of a trim panel which is structurally rigid to provide a durable door trim panel assembly for the vehicle door and yet has structurally weakened portions by which the trim panel predictably yields upon imposition of a force thereagainst to preferably communicate the imposed impact energy into an energy absorbing collapsible means underlying the trim panel.

The present invention will now be described, by way of example, with reference to the 2.

following description of a preferred embodiment, and the appended drawings. in which:-

Figure 1 is an elevation view of a vehicle door according to the invention and having dashed lines to indicate the location of aperture slots in the trim panel concealed beneath the trim cover; Figure 2 is a section view taken through the vehicle door in the direction of arrows 2-2 of Figure 1; and Figure 3 is an enlarged fragmentary view looking in the direction of arrows 3-3 of Figure 2 having parts broken away and in section showing the plurality of aperture slots provided in the trim panel.

Referring to Figures 1 and 2 it is seen that a vehicle door 10 includes an outer panel 12 and an inner panel 14 which are attached together in spaced apart relation by welding and hem flanging the peripheral edges thereof. A space 16 defined between the outer panel 12 and inner panel 14 provides a storage space for a window panel 18. In addition, door beam 20 is situated in the space 16 and extends longitudinally between the front and rear of the vehicle door 10.

The inside of the inner panel 14 is concealed by a door trim panel assembly generally indicated at 24. The door trim panel assembly 24 includes an inner absorbing member 26 comprised of an energy absorbing material such as expanded polystyrene foam, and thereby defining energy absorbing collapsible means. The inner absorbing member 26 is covered by a trim panel 28 which overlies the inner absorbing member 26 and is formed of a suitable rigid material such as moulded plastic or pressed hardboard. The trim panel 28 is covered with a trim cover 30 such as vinyl, leather, cloth., carpeting, or the like which is adhesively or otherwise secured on to the face of the trim panel 28 to provide a decorative cover facing the vehicle occupant.

An arm rest 32 is also provided on the vehicle door 10. As shown in Figure 2, the arm rest 32 is a foam and plastic assembly including a moulded plastic cap 34 which is sandwiched between a protruding portion 36 of the trim panel 28 and a mating portion 29 of the inner absorbing member 26 which defines a cavity 38. Reference may be had to US patent no. 4,783,114 for detailed description of the structure and function of the arm rest structure shown herein, as well as alternative armrest structures.

As best shown in Figure 3, the trim panel 28 of moulded plastic is provided with a plurality of aperture slots 40, 42, 44, and 46 which are moulded in place to structurally weaken the substrate trim panel 28, and thereby define structurally weakened portions. In Figure 1, the dashed lines indicate that these weakening aperture slots may be provided in a series of substantially vertical columns 50. 52, 54, 56 and 58 generally adjacent to the occupant's seated position. Upon the imposition of an occupant impact in generally a perpendicular direction to the trim panel 28 against the door trim panel assembly 24 from inside the vehicle, the arm rest structure 32 collapses into the cavity 38 and the trim panel 28 is also shifted bodily outward toward the inner panel 14 as permitted by energy absorbing yielding and compression and collapse of the foam of the inner absorbing member 26. During such impact imposition, the presence of the plurality of aperture slots 40-46 Y q:

predictably weakens the trim panel 28 permitting yielding thereof so that the impact force is effectively communicated through the trim panel 28 and into the inner absorbing member 26 for optimum management of the impact energy. However, the aperture slots 40-46 do not so substantially weaken the trim panel 28 as to diminish the structural integrity of the vehicle door trim assembly during the rigors of every day use.

It will be understood and appreciated that the aperture slots 40-46 are not limited to deployment in a plurality of columns 50, 52, 54, 56, and 58 as shown in Figure 1, but rather can be deployed in any pattern or configuration which proves beneficial in promoting the controlled communication of impact energy into the inner absorbing member 26. In addition, it will be appreciated that the inner absorbing member 26 herein is not limited to the use of expanded polystyrene foam. For example, another suitable energy absorbing structure is disclosed in US patent no. 4,890, 877.

Thus it is seen that the invention provides a new and improved door trim panel assembly which facilitates the absorption and management of impact energy imposed thereon from inside the vehicle.

Claims

Claims:

1. A vehicle door comprising an outer panel (12) and an inner panel (14) attached together and defining a space (16) therebetween; and a door trim panel assembly (24) mounted on the inner panel on a side thereof facing away from-the outer panel and including a trim panel (28) of substantially rigid material carrying a trim cover (30); characterised in that the trim panel has structurally weakened portions (40-46) therein by which the otherwise rigid trim panel predictably yields upon the imposition of an impact of predetermined magnitude thereagainst to absorb energy.

2. A vehicle door as claimed in claim 1, further comprising energy absorbing collapsible means (26)-interposed between the inner panel (14) and the trim panel (28) for collapsibly absorbing energy upon imposition of a predetermined level of force thereon, the trim panel predictably yielding to effectively communicate any imposed impact into the energy absorbing collapsible means.

3. A vehicle door as claimed in claim 2, wherein the energy absorbing collapsible means (26) supports the trim panel (28).

4. A vehicle door as claimed in any one of claims 1 to 3, wherein the structurally weakened portions comprise a plurality of openings (40-46) formed in the trim panel (28) in a predetermined pattern.

5. A vehicle door as claimed in claim 4, wherein the energy absorbing collapsible means (26) is of a collapsible foam and'the trim panel (28) is of moulded material and has moulded in place aperture slots (40-46) therein defining the plurality of openings.

1 1 Q.

6. A vehicle door as claimed in claim 5, wherein the apertured slots (4046) are formed in a series of spaced columns (50-58).

7. A vehicle door as claimed in any one of claims 1 to 6# wherein the trim panel (28) has an armrest (32) formed integral therein, the structurally weakened portions (40-46) of the trim panel promoting the collapse of the armrest upon imposition of force thereagainst.

Published 1991 atThe Patent Ofilce. State House. 66171 High Holborn. London WC1R47P. Further copies may be obtained from Sales Branch. Unit 6. Nine Mile Point Cwmfelinfach. Cross Keys, NewporL NPI 7HZ. Printed by Multiplex techniques ltd, St Mary Cray, Kent.