TECHNICAL FIELD

The present invention relates to an inner door panel for a vehicle door; a vehicle door; a vehicle; and a method of manufacturing a vehicle door.

BACKGROUND

A conventional vehicle door comprises an inner door panel, an outer door panel and a trim panel. A side anti-intrusion beam is provided within the structure of the vehicle door to protect passengers within the cabin of the vehicle. The anti-intrusion beam typically takes the form of a reinforcing member, for example made of high-strength steel, which is fixedly mounted to the inner door panel of the vehicle door and may extend to the door hinge brackets. In the event of a collision, the anti-intrusion beam is effective in absorbing impact energy and transmitting the impact energy to the adjoining structure. The anti-intrusion beam is a separate component which is attached to the door structure, adding to the complexity of the manufacturing process.

GB 2331778 discloses a door assembly comprising a formed inner door panel which can support an anti-intrusion beam. The disclosed arrangement is intended to be formed from steel and the inner door panel is in the form of an outer hoop having an inclined cross member.

At least in certain embodiments, the present invention sets out to overcome or ameliorate at least some of the shortcomings associated with prior art vehicle doors.

SUMMARY OF THE INVENTION

Aspects of the present invention relate to an inner door panel for a vehicle door; a vehicle door; a vehicle; and a method of manufacturing a vehicle door as claimed in the appended claims.

According to a further aspect of the present invention there is provided an inner door panel for a vehicle door, the inner door panel comprising:

a perimeter portion for connection to an outer door panel; and

a central section forming an integral anti-intrusion panel;

wherein at least one elongate concavity having a substantially continuous surface is formed in an inner face of said central section. l In the assembled vehicle door of an embodiment, an outer door panel is disposed to an exterior of the inner door panel. The at least one elongate concavity can help to maintain a displacement between the inner door panel and the outer door panel in the event of a side loading, for example due to a side-impact. At least in certain embodiments, the at least one elongate concavity can thereby improve the structural integrity of the vehicle door. Moreover, the integral formation of the anti-intrusion panel with the inner door panel can simplify the assembly process. The inner door panel can be formed as a single component, for example by pressing a metal sheet, allowing the vehicle door to be assembled without the need to mount a separate anti-intrusion beam. The formation of the first elongate concavity with a substantially continuous surface can promote the transmittal of energy to fixed anchor points, such as hinge brackets and latches. At least in certain embodiments, the inner door panel can obviate the need for separate reinforcing elements. The inner door panel has an inner face and an outer face. The central section of the inner door panel can have a corrugated profile. The at least one elongate concavity forms an elongate depression or recess in the inner face of the inner door panel. A corresponding projection is formed in an outer face of the inner door panel. The profile of said at least one elongate concavity can be configured to manage energy transmittal within the inner door panel and the assembled vehicle door. In transverse section, the elongate concavity could comprise a polygonal section, for example made up of one or more angled sections. Alternatively, in transverse section, the elongate concavity can comprise a continuous curved section. The elongate concavity can, for example, comprise a part-cylindrical section or a half sine-wave section. At least in certain embodiments, the continuous curved section can manage the transmittal of energy within the inner door panel.

The central section can be inset relative to the perimeter portion of the inner door panel. In the assembled door, this arrangement forms a cavity between the inner door panel and an outer door panel. An energy-absorbing material can be provided between the inner door panel and the outer door panel. The energy-absorbing material can absorb energy in the event of an impact and can also facilitate transmittal of energy, particularly in a dynamic way to each end of the vehicle door. For example, a foam material (such as structural foam) or honeycomb (such as aluminium honeycomb) can be provided in the cavity provided between the inner and outer door panels. Equally, a composite structure can be disposed between the inner and outer door panels. The at least one elongate concavity operatively projects towards an outside of the vehicle door. The at least one elongate concavity can extend at least partway (or completely) along a length of the central section of the inner door panel. In use, the at least one elongate concavity can extend at least substantially longitudinally (i.e. parallel to a longitudinal axis of the vehicle).

The inner door panel can comprise first and second elongate concavities formed in the inner face of said central section. The first and second elongate concavities can have the same sections and/or plan forms. Alternatively, the first and second elongate concavities can have different sections and/or plan forms. The first and second elongate concavities can be spaced apart from each other. The central section can comprise a planar section disposed between said first and second elongate concavities. The first concavity can have a first longitudinal axis and the second concavity can have a second longitudinal axis. The first and second longitudinal axes can be arranged substantially parallel to each other; or can be inclined at an angle relative to each other. The first and second longitudinal axes can extend substantially parallel to a main longitudinal axis of the vehicle door or can be arranged at an angle relative to said main longitudinal axis.

The central section can comprise a substantially continuous surface. The inner door panel could be formed from a composite material. For example, the inner door panel could be formed from carbon fibres embedded in a resin. In this arrangement, the inner door panel can be moulded. One or more ribs could be formed on an inner or outer surface of the inner door panel to strengthen the inner door panel. Alternatively, the inner door panel can be made of metal, such as aluminium. The inner door panel can be formed from a single pressed metal sheet. The metal sheet can be an aluminium sheet having a thickness of between 2 mm and 3 mm. The metal sheet can have a thickness of 2.5mm.

In a further aspect, the present invention relates to a vehicle door comprising an inner door panel as described herein. The vehicle door can comprise an outer door panel disposed to an exterior of the inner door panel. A cavity can be formed between the inner and outer door panels. A deformable filler material, such as a composite honeycomb structure or a foam material, can be provided in said cavity. A trim panel can be mounted to an interior of the inner door panel. The trim panel can have a decorative finish, for example a fabric or leather trim. The outer door panel could be formed from metal (such as aluminium) or could be a composite structure (such as carbon fibres embedded in a resin). One or more ribs can be formed on an inner surface of the outer door panel. According to a still further aspect, the present invention relates to a method of fabricating the inner door panel described herein. The method can comprise pressing a metal sheet to form said integral anti-intrusion panel. According to a yet further aspect of the present invention, there is provided a motor vehicle comprising at least one vehicle door as described herein.

Unless indicated otherwise, the terms "inner" and "outer" used herein are to be understood as referring to the relative position/orientation of the respective features in the assembled vehicle door when fitted to a motor vehicle. The inner surfaces are directed inwardly towards an interior of the motor vehicle and the outer surfaces are directed outwardly towards an exterior of the motor vehicle. Similarly, the inner door panel is disposed inside the outer door panel when the assembled vehicle door is installed. Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. For example, features described with reference to one embodiment are applicable to all embodiments, unless such features are incompatible.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying figures, in which:

Figure 1 shows an exploded perspective view of a vehicle door assembly incorporating an inner door panel in accordance with an embodiment of the present invention; and

Figure 2 shows a perspective view of an inner door panel of a vehicle door in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

A vehicle door 1 in accordance with an embodiment of the present invention will now be described with reference to Figures 1 and 2. The vehicle door 1 in the present embodiment is a frameless door of a motor vehicle, such as an automobile. The illustrated vehicle door 1 is the front right hand door, extending between the A-pillar and B-pillar of the motor vehicle. It will be appreciated that the features of the vehicle door 1 are reversed for a left hand door. The vehicle door 1 has a main longitudinal axis X and comprises an inner door panel 2 and an outer door panel 3. The inner door panel 2 forms a structural element of the assembled door and is fabricated as a unitary item from a single sheet of metal pressed into shape. The outer door panel 3 forms the exterior of the vehicle door 1 and its outer surface defines an exterior "A" surface. The inner and outer door panels 2, 3 are joined along their common outer edges (along the top, bottom, front and rear) to form a box section which provides the main structural component of the vehicle door 1 . A door trim panel (not shown) is attached to an interior of the inner door panel 2. A door window (not shown) and associated operating mechanism are disposed between the inner door panel 2 and the door trim panel. Moreover, an elongate aperture is maintained between the inner door panel 2 and the door trim panel along their upper edges to accommodate the door window and associated seals.

The inner door panel 2 comprises a perimeter portion 4 extending around the outer circumference of a central section 5. The perimeter portion 4 and the central section 5 are illustrated by dashed lines in Figure 2. A sidewall 6 is formed around the central section 5 to offset the perimeter portion 4 outwardly from the central section 5 in a direction orthogonal to a major surface of the central section 5. Thus, the perimeter portion 4 and the central section 5 are arranged in different planes, defined by their respective major surfaces. This offset creates a door cavity between the inner door panel 2 and the outer door panel 3 in the vehicle door 3. A deformable material, such as foam or a honeycomb structure can optionally be disposed in the door cavity.

The inner door panel 2 has an inner face 7 and an outer face 8 and is formed from a single pressed aluminium sheet having a thickness of 2.5mm. A first concavity 9 and a second concavity 10 are formed in the central section 5 of the inner door panel 2. The first and second concavities 9, 10 are formed in the inner face 5 of the inner door panel 2 and project outwardly towards the outer door panel 3. In transverse cross-section, the first and second concavities 9, 10 have a continuous curved (arcuate) profile and project into the cavity formed between the inner door panel 2 and the outer door panel 3. The offset between the perimeter portion 4 and the central section 5 of the inner door panel 2 is such that the first and second concavities 9, 10 are spaced apart from the outer door panel 3 in normal use.

The first and second concavities 9, 10 are elongated and have respective first and second longitudinal axes X1 , X2 arranged substantially parallel to each other. The first and second longitudinal axes X1 , X2 extend along the length of the vehicle door 1 (substantially parallel to the main longitudinal axis X of the vehicle door 1 ) such that a front end of each concavity 9, 10 is disposed towards the front of the vehicle door, and a rear end of each concavity 9, 10 is disposed towards the back of the vehicle door. The first and second concavities 9, 10 could be arranged such that the first and second longitudinal axes X1 , X2 are inclined at an angle relative to the longitudinal axis X of the vehicle door. The depth of the first and second concavities 9, 10 along their length, relative to the surrounding sections of the central section 5, is substantially uniform. In alternate arrangements, the depth of the first concavity 9 and/or the second concavity 10 could vary to alter the structural properties of the inner door panel 2 along the length of the vehicle door.

A section of the central section 5, disposed between the first and second concavities 9, 10, forms an anti-intrusion panel 1 1 . The anti-intrusion panel 1 1 is thereby formed integrally with the inner door panel 2 and it is not necessary to provide additional strengthening or reinforcement. The first and second concavities 9, 10 and the anti-intrusion panel 1 1 are substantially continuous without any apertures or cut-outs. This arrangement can assist with managing the transfer of energy through the vehicle door to the door fixing points (such as front mounting hinges and a rear latch mechanism).

A first aperture 12 is formed at the top of the inner door panel 2 for mounting a door handle or latch (not shown), and other smaller apertures 13 are formed for mounting assemblies, such as the window operating mechanism, within the vehicle door. Optionally, other features may also be shaped and formed as part of the inner door panel 2. For example, a hinge plate 14, a mirror plate 15 and a latch plate 16 can be formed integrally in the inner door panel 2.

In the present embodiment, two smaller concavities 17, 18 are formed towards the bottom of the central section 5. The smaller concavities 17, 18 are arranged along a common third longitudinal axis X3, one directly behind the other. The third longitudinal axis X3 is substantially parallel to the main longitudinal axis X of the vehicle door such that, in use, the smaller concavities 17, 18 are aligned horizontally. The first and second concavities 9, 10 can improve the structural integrity of the assembled vehicle door 1 . The first and second concavities 9, 10 help to preserve the spaced positioning of the inner and outer door panels 2, 3 relative to each other in the event of a side loading. This can help to improve the integrity of the vehicle door 1 . The first and second concavities 9, 10 may collapse and flatten in the event of continued loading, but continue to provide a protective barrier. The provision of an energy-absorbing material between the inner and outer door panels 2, 3 can help to control the absorption and/or transmittal of energy through the vehicle door 1 . It will be appreciated that various changes and modifications can be made to the embodiment described herein without departing from the spirit and scope of the present invention.

Further aspects of the present invention are set out in the following numbered paragraphs:

1 . An inner door panel for a vehicle door, the inner door panel comprising:

a perimeter portion for connection to an outer door panel; and

a central section forming an integral anti-intrusion panel;

wherein at least one elongate concavity having a substantially continuous surface is formed in an inner face of said central section.

2. An inner door panel as described in paragraph 1 , wherein said at least one elongate concavity extends at least partway along a length of the central section of the inner door panel.

3. An inner door panel as described in paragraph 1 , wherein first and second said elongate concavities are formed in the inner face of said central section.

4. An inner door panel as described in paragraph 3, wherein said first elongate concavity has a first longitudinal axis and the second elongate concavity has a second longitudinal axis, the first and second longitudinal axes being substantially parallel to each other.

5. An inner door panel as described in paragraph 4, wherein, in use, said first and second longitudinal axes are arranged substantially horizontally.

6. An inner door panel as described in paragraph 1 , wherein the inner door panel is formed from a single pressed metal sheet.

7. An inner door panel as described in paragraph 6, wherein the metal sheet is an aluminium sheet having a thickness of between 2 mm and 3 mm. 8. A vehicle door comprising an inner door panel as claimed in any one of the preceding claims. 9. A vehicle door as claimed in described in paragraph 8 comprising an outer door panel disposed to an exterior of the inner door panel 10. A vehicle door as claimed in described in paragraph 9, wherein the inner door panel is connected to said outer door panel along at least a portion of said perimeter portion.

1 1 . A vehicle door as claimed in described in paragraph 9, wherein the at least one elongate concavity projects outwardly towards said outer door panel.

12. A vehicle door as described in paragraph 8 comprising a trim panel disposed to an interior of said inner door panel.

13. A motor vehicle comprising at least one vehicle door as described in paragraph 9.

14. A method of fabricating the inner door panel as described in paragraph 1 comprising pressing a metal sheet to form said integral anti-intrusion panel.