Technical Field of the Invention

The present invention relates to a trim panel for an automotive vehicle of the type covering an airbag device, said trim panel comprising a door for the passage of an airbag cushion, said door being movable between a closed position, wherein the door covers the airbag device, and an open position, wherein the door is moved to enable the passage of the airbag cushion, said door being moved by at least a flap mounted on a hinge member formed by a flexible net, a first end part of the net being overmoulded by the flap, and a second end part of the net being overmoulded by a fixing element attached to a support member of the airbag device, said support member being fixed to the trim panel, the articulation of the hinge member being formed by a net hinge part extending between the first and second end parts.

This trim panel is for example used to form a dashboard. Automotive dashboards often comprise an airbag which forms a safety device and which, in service, passes through a dashboard aperture closed by a flap and inflates in front of a passenger.

Background of the Invention

A number of devices are already known for articulating a flap onto a dashboard body and creating the conditions required for deployment of the air bag without additionally endangering the passengers.

One of these devices is for example disclosed in document

WO-2007/147966. In this document, the articulation between the flap and the dashboard body is performed by a net, which comprises a centre part extending between two end parts, one of the end part being overmoulded by the flap and the other being overmoulded by a fixing element attached to the support member of the airbag device. The centre part, which is loose between the two ends, forms a soft hinge having the required flexibility and which remains efficient, even at low temperatures, i.e. which does not present the risk of breaking at low temperatures. The net enables both the flap to rotate during the expansion of the airbag cushion and to maintain the flap attached to the dashboard, preventing it to escape in the vehicle compartment, which could be dangerous.

However, the length of the net overmoulded by the fixing element is relatively small. The energy due to the expansion of the airbag cushion imposes a great deal of stress on the net, which tends to be damaged inside the fixing element. This damaging can lead to tearing of the net or to expulsion of the net from the fixing element. In this case, the net does not fulfil its functions and the device can be dangerous for the passengers of the vehicle in case of a shock.

Furthermore, there is a small space to accommodate the fixing element in the dashboard, which prevents to simply increase the length of the end part of net to be overmoulded by the fixing element. Summary of the Invention

One of the aims of the invention is to solve the aforementioned problem, by providing a device enabling to increase the length of the net overmoulded by the fixing element without substantially increasing the space requirement to accommodate said fixing element.

To that end, the invention relates to a trim panel of the aforementioned type, wherein the fixing element comprises at least a first portion and a second portion, said portions extending in different directions so as to define an elbow portion between them, the second end part of the net being overmoulded by at least said first and second portions of the fixing element.

By properly arranging the elbow portion of the fixing element, it is possible to increase the length of the end part of the net overmoulded by the fixing element, without substantially increasing the space required to accommodate the fixing element. Therefore, the risks of damaging the net inside the fixing element due to the cushion expansion energy are reduced without impairing the arrangement of the trim panel to accommodate a large fixing element.

According to other features of the invention:

- the fixing element comprises a third portion, said third portion defining with the second portion a second elbow portion, the second end part being further overmoulded by said third portion ;

- the second end part of the net comprises an extreme end part protruding from the fixing element opposite the hinge part of the net, said extreme end part comprising an abutment element, so that, during the expansion of the airbag cushion, the abutment element prevents the second end part from coming out of the fixing element;

- the fixing element comprises a recess, the hinge part of the net being accommodated in said recess when the door is in the closed position;

- the hinge part of the net is maintained in a retracted state when the door is in the closed position, the hinge part passing in a deployed state when the door moves to the open position, the hinge member forming the only attachment of the door to the trim panel when said door is in the open position;

- the hinge part is folded in the retracted state,

- said hinge part is maintained in the retracted state by a fusible seam passing through the folds of the hinge part or by adhering the folds of the hinge part together; - the hinge part is compressed in the retracted state so that its volume is reduced compared to the hinge part in the deployed state;

- the fixing element is attached to the support member by attachment means, said attachment means being arranged to maintain the fixing element attached to the support member when the door moves from the closed position to the open position; and

- the support member and the flap are attached to a substrate covered by a skin, forming the outer face of the trim panel, the door being formed in said substrate and said skin.

Brief Description of the Drawings

Other features and advantages of the invention will appear by reading the following specification, given by way of example and made in reference to the appending drawings, wherein:

- Fig. 1 is a sectional view of part of a trim panel showing a fixing element according to a first embodiment of the invention,

- Fig. 2 is an enhanced view of area II of Fig. 1 showing the fixing element,

- Fig. 3 is a sectional view of part of a trim panel showing a fixing element according to a second embodiment of the invention,

- Fig. 4 is a sectional view of part of a trim panel showing a fixing element according to a third embodiment of the invention.

Detailed Description of the Preferred Embodiments

The following specification is made relative to a trim panel 1 for a dashboard of an automotive vehicle. However, it is to be understood that the invention can apply to any trim panel of an automotive vehicle comprising an airbag intended to cover an airbag device, such as a door panel or other. With reference to Fig. 1 , there is shown a trim panel 1 intended to form the outer face of a dashboard of an automotive vehicle. The trim panel 1 comprises a substrate 2 covered by a skin 4, forming the outer face 6 of the trim panel 1, i.e. the visible face of the trim panel 1. In the embodiment shown in the figures, the substrate 2 is a rigid insert. It could also be an insert covered by a foam layer. The skin 4 and the substrate 2 could also be formed by the same element, if said element has a satisfactory aspect.

The substrate 2 covers an airbag device 8 which is attached to the inner face 10 of the substrate 2 by a support member 12, for example made of plastics material, to which a housing 14 of the airbag device 8 is fixed for example by hooking means 16, as shown in Fig. 1, or other fixing means. The support member 12 is itself fixed to the inner face 10 of the substrate 2 for example by welding or by other fixation means.

The housing 14 comprises an aperture 18 arranged opposite a door 20 formed in the trim panel 1, i.e. the door is formed by an area of the substrate 2 and by an area of the skin 4 arranged opposite the aperture 18. The door 20 is movable between a closed position, wherein the door 20 closes the aperture 18 and covers the airbag device 12, and an open position (shown in dot-lines in Fig. 1), wherein the door 20 is moved away from the aperture 18 to allow the passage of an airbag cushion deploying through the aperture 18 towards the vehicle compartment. The support member 12 surrounds the opening 18 and forms guiding means to guide the direction of expansion of the airbag cushion.

In the closed position, the door 20 is for example integral with the rest of the trim panel 1 , i.e. the door 20 is not visible from the vehicle compartment when said door is in the closed position, which gives a good appearance to the outer face 6 of the trim panel 1. The door 20 is for example surrounded by a weakening line formed in the substrate 2 and in the skin 4 and which allows said substrate 2 and said skin 4 to tear around the door 20 when the airbag cushion is deployed. The door 20 can then move in the open position. According to another embodiment, the door 20 is separated from the rest of the trim panel 1 and is attached to said trim panel 1 in the closed position by fixing means, as conventionally known.

The door 20 is not sufficiently rigid to guarantee its movement to the open position during the deployment of the airbag cushion. For example, under the effect of the force applied by the cushion against the door 20 during its deployment, the door 20 could be deformed without tearing the weakening line surrounding it or without breaking the fixation means of the door 20 to the rest of the trim panel 1. In order to ensure that the door 20 will move from the closed position to the open position under the effect of the deployment of the airbag cushion, at least one rigid flap 22 is arranged against the door 20 opposite the aperture 18. The cushion therefore presses on said flap 22 during its deployment. The flap 22 is for example made of the same material as the support member 12, i.e. plastics material. The material is chosen to guarantee that the force applied on the flap 22 will lead to the movement of the door 20 to its open position. Therefore, the flap 22 enables an optimal transmission of the energy due to the deployment of the airbag to the door 20 and its weakening line or fixing means. The flap 22 is for example welded or glued to the inner face of the door 20. According to another embodiment, two flaps could be arranged against the door 20 if the door 20 is formed in two parts separating from each other when the door 20 moves in the open position.

The flap 22 is articulated relative to the trim panel 1 , outside the door 20, in order to enable the movement of the door 20 from the closed position to the open position. Therefore, the flap 22 is hinged to the support element 12 via a soft hinge member 24 formed by a net. The use of a net to form a flexible and soft hinge member is known. The net is for example a knitted or woven net, as known.

The net comprises a first end part 26, attached to the flap 22, and a second en part 28, attached to the support member 12, a central hinge part 30, forming the articulation of the hinge member, extending between said first 26 and second 28 end parts.

The first end part 26 is overmoulded by the flap 22, i.e. the material forming the flap 22 is injected over the first end part 26 and said material covers and penetrates the meshes of the net forming the first end part 26. Such an overmoulding technique guarantees a good fixation of the first end part 26 to the flap 22, said fixation having a high resistance preventing the flap 22 from separating from the first end part 26 during the deployment of the airbag.

During the mounting of the airbag device, the second end part 28 of said hinge member 24 is overmoulded by a fixing element 32, separated from the support member 12, and attached to said support member 12, before the support member 12 and the flap 22 are fixed to inner face 10 of the trim panel 1.

The fixing element 32 is therefore a separate plastics element, the material of which is injected over the second end part 28 and said material covers and penetrates the meshes of the net forming the second end part 28. The fixing element 32 is attached to the support member 12 by attachment means 34, such as a screw (Fig. 1 , 2 and 3) or clips made integral with the fixing element (Fig. 4) or a combination of a screw and clips or other suitable means. The attachment means 34 and the support element 12 are arranged in order to sustain the forces applied on the fixing element 32 during the deployment of the airbag and prevent the fixing element 32 from separating from the support element 12 during said deployment. The shape of the support member 12 is adapted to receive the fixing element 32, for example in a cavity 36, and comprises a bore 38 for receiving the attachment means 34.

The fixing element 32 is arranged to overmould a large length of the net forming the second end part 28 in order to prevent the net to be damaged inside the fixing element 32 under the effect of the energy of deployment of the airbag and ensure that the hinge member 24 remains attached to the fixing element 32 and therefore to the trim panel 1 during the deployment of the airbag. In order to do so, the fixing element 32 comprises at least a first portion 40 and a second portion 42 extending, in different directions so as to define an elbow portion between them, the first 40 and second 42 portions both overmoulding the second end part 28 of the hinge member 24. By providing an elbow portion on the fixing element 32, the length of the net overmoulded by said fixing element 32 can be increased relative to a fixing element 32 having only a straight portion, without substantially increasing the space requirement to receive the fixing element 32. Indeed, the change of direction between the first portion 40 and the second portion 42 enables to save space and the net, passing through said first 40 and second 42 portions, can have a greater length covered by said portions. The angle between the first 40 and second 42 portions is chosen to optimize the space requirement of the fixing element 32 relative to its environment, and in particular to the shape of the support element 12. This angle is for example comprised between 10° and 160°. The shape of the fixing element 32 can be chosen such that the fixing element 32 can be made by a single injection step and taken out of a mould easily.

According the embodiment shown in the figures, the fixing element 32 further comprises a third portion 44 forming another elbow portion with the second portion 42, the second end portion 28 of the hinge member 24 being also overmoulded by said third portion 44, to further increase the length of the net overmoulded by the fixing element 32. The third portion 44 can also serve as anchoring means for attaching the fixing element 32 to the support member 12, as shown in Fig. 2 and 3.

According to an embodiment shown in Fig. 2 and 4, the second end part 28 of the net further comprises an extreme end part 46 protruding from the fixing element 32 opposite the hinge part 30 of the net, for example protruding from the third portion 44. The extreme end part 46 extends therefore outside of the fixing element 32. The extreme end part 46 comprises an abutment element 48, so that, during the expansion of the airbag cushion, the abutment element 48 prevents the second end part 28 from coming out of the fixing element 32. Indeed, if the energy due to the deployment of the airbag is too important and the net tend to be pulled out of the fixing element 32, said net will not be able to come out of the fixing element 32, since the abutment means 48 will come in contact with the fixing element 32 and prevent further displacement of the net. For example, the extreme end part 46 is folded on itself and a seam attaches the folds of the extreme end part 46 together, said seam forming the abutment means 48. Such abutment means 48 and others, are for example described in document WO-2009/136041.

The centre hinge part 30 of the hinge member 24 has a certain length to make sure that the door 20 will be sufficiently spaced from the aperture 18 during the expansion of the airbag cushion to ensure that the passage is free for said cushion. When the door 20 is in the closed position, there is not much space to accommodate said hinge part 30 of the net. Furthermore, the hinge part 30 can not be left hanging under the door 20. Indeed, tools are used, for example welding tools, to attach the flap 22 to the door 20 after the fixing element 32 has been attach to the support member 12 and said tools could damage the hinge part 30 if said hinge part was left in the way of the tools, i.e if the hinge part extends under the door 20. If the hinge part 30 is damaged, it is not guaranteed the net will be able to retain the door 20 during the expansion of the airbag cushion, which could be very dangerous. Indeed, the hinge member 24 is the only attachment of the door 20 to the trim panel 1 when said door 20 is in the open position. Therefore, if the hinge member 24 does not retain the door 20, said door 20 is ejected in the vehicle compartment during the expansion of the airbag cushion and can injure the passengers of the vehicle.

In order to accommodate the hinge part 30 of the net when the door 20 is in the closed position, the fixing element 32 comprises a recess 50 in which the hinge part 30 is disposed. The recess 50 is for example formed by the first 40, second 42 and third 44 portions of the fixing element 32, as shown in Fig. 4, or by the fixing element 32 and a part of the support member 12 as shown in Fig. 3, or by a particular shape of the fixing element 32 as shown in Fig. 1 and 2. When the hinge part 30 is disposed inside said recess 50, the hinge part 30 does not extend under the door 20 and the flap 22 can be attached to the door 20 without the risk of damaging the hinge part 30.

In order to be able to be placed inside the recess 50, the hinge part 30 is placed in a retracted state when the door 20 is in the closed position. In the embodiment shown in the figures, the hinge part 30 is folded on itself in the retracted state and is maintained is said state by a fusible seam 52 passing through the folds (Fig. 2) or by making the folds adhere to each other for example by partial melting of the surface of the folds. The seam 52 or the adherence of the folds together are arranged to break during the movement of the door 20 so that the hinge part 30 can unfold and pass in a deployed state (in dot lines in Fig. 1). In the retracted state, the hinge part 30 therefore requires less space to be accommodated. According to another embodiment (not shown), the hinge part 30 is compressed in the retracted state so that its volume is reduced compared to the hinge part 30 in the deployed state.

It should be noted that the fixing element 32 can be formed in several pieces connected together by the second end part 28 of the net, said second end part 28 then comprising a portion extending outside the fixing element 32 between the pieces of the fixing element 32, as shown in Fig. 3.

It should be understood that if the door 20 is made in two parts, two hinge member 24 and two fixing element 32 are provided to hinge the two flaps 22 on the support member 12.

The above described trim panel 1 is particularly adapted to be used in the dashboard of an automotive vehicle and guarantees the safe functioning of an airbag device by preventing the hinge member 24 to be deteriorated or ejected during the deployment of the airbag cushion. Furthermore, the hinge member 24 requires a small space to be accommodated so that it can be easily integrated under the trim panel 1 with other components extending in its environment.