Pedestrian protection device

A pedestrian protection device for a motor vehicle having a windscreen and an A-pillar extending adjacent a side edge of the windscreen. The protection device comprises a base member securable to the A-pillar of the motor vehicle, and a trim member moveable relative to the base member. A deployment mechanism is operable upon actuation of the device to drive the trim member away from the base member from an initial position in which the trim member is proximal to the base member, to a deployed position in which the trim member is spaced from the base member. The deployment mechanism comprises a plastically deformable member interconnecting the base member and the trim member and which is arranged, in said deployed position of the trim member, to absorb impact energy arising from impact between a pedestrian and the trim member in compression.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 35 U.S.C. § 371 national phase of PCT International Application No. PCT/EP2021/074434, filed Sep. 6, 2021, which claims the benefit of priority under 35 U.S.C. § 119 to German Patent Application No. 10 2020 124 824.5, filed Sep. 23, 2020, the contents of which are incorporated herein by reference in its entirety.

FIELD

The present invention relates to a pedestrian protection device. More particularly, the present invention relates to a pedestrian protection device for a motor vehicle, and to a motor vehicle equipped with such a device.

BACKGROUND

When a motor vehicle is involved in a frontal impact with a pedestrian, it is known to be common for the body of the pedestrian to be thrown over or onto the hood of the vehicle and to strike the windscreen area of the vehicle. Whilst pedestrian impact with the windscreen itself can cause significant injury, the highest risk parts of the windscreen area of a motor vehicle are considered to be the vehicle's A-pillars. The A-pillars form part of the structure of a motor vehicle body, and extend upwardly and rearwardly from the region of the rear corners of the vehicle's hood, along respective side edges of the windscreen. The A-pillars of a vehicle are important structural members because they must be sufficiently strong to support not only the windscreen but also the vehicle's roof during normal driving and also in the event of a rollover accident. These structural requirements of a vehicle's A-pillars make them difficult to engineer such that they absorb sufficient impact energy from a striking pedestrian to prevent serious injury to the pedestrian.

In an attempt to render motor vehicles safer to pedestrians in the event of an impact, it has been proposed previously to provide a motor vehicle with a so-called pedestrian airbag of a type which, if vehicle sensors indicate that a collision with a pedestrian is occurring or is likely to occur, inflates to cover the left and right A-pillars of the vehicle, and optionally also the windscreen therebetween. Typically, an airbag of this general type is provided in an initially folded and/or rolled package and is stored beneath a rear part of the vehicle's hood, for inflation in a generally rearwards direction across the windscreen and A-pillars. The rear of the hood may be lifted by another air-bag, a piston or another arrangement, to allow sufficient space for the pedestrian airbag to inflate so that it deploys in a manner effective to cover the A-pillars of the vehicle, and optionally the windscreen, thereby cushioning the impact of a pedestrian with these parts of the vehicle.

Although pedestrian airbags of the general type described above can provide a good level of protection to pedestrians in the event of impact with either A-pillar of a motor vehicle, they can present a packaging challenge to motor vehicle designers. This is because conventional pedestrian airbags are actually very large in size in comparison to other types of airbags used in motor vehicles, such as driver airbags, which means that the initially folded and/or rolled airbag package is relatively large, and the inflator required to inflate the airbag is also large due to the volume of gas required to achieve adequate inflation. Both of these factors make it difficult to accommodate conventional pedestrian airbag modules in many modern motor vehicles, where space is at a premium for vehicle designers, particularly in the region of the engine bay where such airbags must often be installed.

There have been proposals to provide the A-pillars of a motor vehicle with individual respective airbags, in an effort to provide sufficient pedestrian protection from impact with the A-pillars using relatively small airbags. However, these arrangements can also present significant packaging difficulties, as well as additional challenges in terms of ensuring that the airbags deploy with sufficient coverage over the A-pillars to provide effective protection. Whilst good deployment characteristics might be achievable by housing the airbags inside or adjacent the A-pillars themselves, such that the uninflated airbag packages extend along the A-pillars, this is extremely difficult to achieve in practice due to the relatively slender configuration of the A-pillars, which is necessary to ensure that the driver of the vehicle is not presented with dangerous blind spots in his or her view through the windscreen.

It would therefore be desirable to provide an alternative pedestrian protection apparatus, to provide adequate protection to a pedestrian against impact with a motor vehicle's A-pillars, without requiring an airbag arrangement, and which can be more easily accommodated into the design of a motor vehicle, in an unobtrusive manner.

The present invention has been devised in light of the above considerations.

SUMMARY

According to a first aspect of the present invention, there is provided a pedestrian protection device for a motor vehicle of a type having a windscreen and an A-pillar extending adjacent a side edge of the windscreen, the protection device comprising: a base member securable to the A-pillar of the motor vehicle; a trim member moveable relative to said base member; and a deployment mechanism operable upon actuation of said device to drive said trim member away from said base member from an initial position in which the trim member is proximal to said base member, to a deployed position in which the trim member is spaced from the base member; wherein: said deployment mechanism comprises a plastically deformable member interconnecting said base member and said trim member and which is arranged, in said deployed position of said trim member, to absorb impact energy arising from impact between a pedestrian and said trim member in compression.

Optionally, said base member and said trim member are both elongate, and are arranged so as to be substantially parallel to one another in said initial position; said deployment mechanism being operable to maintain said parallelism during movement of said trim member from said initial position to said deployed position.

Said deployment mechanism may comprise a parallel motion linkage arrangement. The deformable member may form part of said parallel motion linkage arrangement.

Optionally, said deformable member is substantially elongate and formed of ductile material.

In some embodiments it is envisaged that the deformable member may be provided in the form of a metal strut and may, for example, be formed of steel, aluminium or other suitable ductile metals.

The trim member is optionally formed of plastic. The base member may also be formed of plastic material.

Conveniently, said deformable member may be pivotally connected to said base member and pivotally connected to said trim member.

Advantageously, said deployment mechanism is operable to drive said trim member away from said base member via pivotal movement of said deformable member relative to said base member and said trim member.

In some embodiments, the deployment mechanism comprises a plurality of said plastically deformable members.

In such embodiments, each of said deformable members may comprise a pair of non-parallel limbs terminating in cranked ends which are pivotally connected to said base member. Optionally, said plurality of deformable members are arranged in an initial nested relationship relative to one another in an initial un-deployed configuration of the device, such that the limbs of at least one said deformable member are at least partially received between the limbs of an adjacent deformable member. In some embodiments of this type, it is envisaged that said plurality of deformable members may be received within said base member in said initial nested relationship.

Optionally, said deployment mechanism further comprises a lifter member engaged with each said deformable member and which is moveable to urge said deformable members from respective initial positions to respective deployed positions in synchronism.

Conveniently, said deployment mechanism further comprises a pyrotechnical actuator operable to urge said trim member from said initial position towards said deployed position.

It is envisaged that the pyrotechnical actuator may be operable to move said lifter member and thereby urge said deformable members from respective initial positions to respective deployed positions in synchronism.

Optionally, the lifter member is provided in the form of an elongate metal plate, which may be formed from steel, aluminium, or another suitable metal.

The pedestrian protection device of the present invention provides effective protection against injury to pedestrians which may be caused by striking the A-pillar of a motor vehicle. The device may be less expensively produced than equivalent conventional airbag arrangements, and is considerably smaller in overall dimensions, in its undeployed condition, than conventional airbag arrangements, meaning that it can more easily be packaged in a modern motor vehicle. The device is also lower in overall weight than a comparable airbag system. Additionally, the device of the present invention has been found to provide more reliable positioning of its key energy absorbing components relative to the A-pillar when deployed, in comparison to a conventional airbag arrangement.

According to a second aspect of the present invention, there is provided a motor vehicle comprising a windscreen, an A-pillar extending along a side edge of the windscreen, and a pedestrian protection device according to the first aspect of the invention, wherein the base member of said pedestrian protection device is secured to said A-pillar, and wherein the trim member of the pedestrian protection device lies against or adjacent the A-pillar to define at least part of an exterior surface of the A-pillar in its initial position.

According to a third aspect of the present invention, there is provided a motor vehicle comprising a windscreen, a pair of A-pillars extending along respective side edges of the windscreen, and a pair of pedestrian protection devices according to the first aspect of the invention, wherein the base member of each said pedestrian protection device is secured to a respective A-pillar, and wherein the trim member of each pedestrian protection device lies against or adjacent the respective A-pillar to define at least part of an exterior surface of the A-pillar in its initial position.

DETAILED DESCRIPTION

FIGS.1and2illustrate the windscreen region of a motor vehicle1of generally conventional configuration and which comprises a hood2, a roof3, and a windscreen4mounted between a pair of structural A-pillars5on respective sides of the vehicle. The A-pillars5extend upwardly and rearwardly from the region of the rear corners of the hood2, and support the roof3and the windscreen4.

The vehicle1illustrated inFIGS.1and2is equipped with a pair of pedestrian protection devices6in accordance with the present invention and of a configuration as described in detail below. Each device6is associated with, and secured to, a respective A-pillar5, and is operable in response to an actuating signal from a sensor configured to detect an impact between the vehicle1and a pedestrian, or the likely occurrence of such an impact, so as to deploy from the initial configuration illustrated inFIG.1to a deployed configuration as illustrated inFIG.2.

As shown inFIG.1, in the initial configuration of each pedestrian protection device6, an elongate trim member7of the device adopts an initial position in which it lies along and against or adjacent the respective A-pillar so as to define part of the exterior surface of the A-pillar. It is envisaged that the shape and configuration of the trim member (including, for example, its surface finish) will be tailored specifically to the vehicle on which the device is installed, so as to create the impression of being an integral and visually consistent part of the A-pillar.

As will be described in more detail below, during deployment of each pedestrian protection device6in response to an actuating signal from the sensor, the trim member7is driven by a deployment mechanism from the initial position illustrated inFIG.1to a deployed position in which it is spaced forwardly from the respective A-pillar5, as illustrated inFIG.2. The principle behind the device6is that a pedestrian impacted by the vehicle1in an accident and launched towards one of the vehicle's A-pillars5will make initial contact with the trim member7of the protection device6in its deployed position, with the resulting space8created between the trim member7and the rigid structure of the A-pillar5permitting the controlled absorption of impact energy, thereby reducing the risk of injury to the pedestrian.

FIG.3is an exploded view showing the main components of an embodiment of the pedestrian safety device6, including the above-mentioned trim member7, an elongate base member9, and components making up a deployment mechanism, namely: a lifter member10; an actuator housing11; an igniter12and associated control cable13; a plurality of deformable members14; and an elongate bracket15configured to attach the deformable members14to the underside of the trim member7.

The plurality of deformable members14of the deployment mechanism are all substantially identical to one another, with each being formed of a suitably strong plastically deformable material such as a ductile metal. In particular embodiments the deformable members14are formed of substantially rigid steel wire, although it is envisaged that in alternative embodiments they could be formed from aluminium wire instead. As illustrated inFIG.3, each deformable member14is generally elongate in form and has an A-shaped configuration comprising a pair of non-parallel limbs16which diverge in a downwards direction, such that the deformable members14have a generally tapered form and are wider at their lower ends than at their upper ends. The upper ends of the two limbs16are interconnected by a short straight section17of the rigid wire, whilst the lower ends of the limbs16terminate in aligned outwardly cranked ends18.

As will be described in more detail below and with specific reference toFIGS.3and4, the plurality of deformable members14are arranged so as to be equi-spaced from one another in a linear array, and are pivotally connected to both the uppermost trim member7and the lowermost base member9, so as to interconnect the trim member7and the base member9in the manner of a parallel motion linkage, such that the trim member7is moveable relative to the base member9whilst being constrained to remain substantially parallel to the base member9.

As shown inFIG.4, the deformable members14are pivotally connected to the trim member7at their upper ends via the elongate bracket15. In particular embodiments it is envisaged that the trim member7will be formed of plastic, and the bracket15, which may also be formed of plastic, is secured to the underside of the trim member7(for example via fasteners20such as screws, or by adhesive, or heat fusion) so as to define a plurality of spaced apart channels21therebetween, each of which receives the upper straight section17of a respective deformable member14as a rotational fit.

The base member9is elongate and has a length generally corresponding to the length of the trim member7. It is proposed that the base member9may be formed from plastic such as, for example, the same plastic material from which the trim member7is formed, and will be secured to an A-pillar of the motor vehicle1so as to extend at least partially along the A-pillar, as will be apparent fromFIGS.1and2.

The base member9comprises a pair of spaced-apart upstanding flanges22along respective side edges, each of which is provided with a series of spaced-apart blind bores23along its length. As will be understood from the partially cut-away view ofFIG.5, the blind bores23formed in each flange22are each aligned across the width of the base member with a corresponding bore23in the opposing flange22, such that each bore23may receive therein a respective cranked end18of a deformable member14as a rotational fit, with the opposing bore in the opposite flange22receiving the other cranked end18of the same deformable member14in an identical manner. In this manner, the lower ends of the deformable members14are pivotally connected to the base member9.

As illustrated most clearly inFIG.3, the base member9is provided with a firing spigot24towards its forwardmost end (the left-hand end in the orientation illustrated), which in some embodiments may be moulded as an integral part of the base member9. The spigot24forms part of the device's actuator arrangement, and is provided towards the end of the base member9which will be mounted at the bottom of the A-pillar when the device6is installed in the motor vehicle, so that it may be accommodated in the so-called ‘scuttle’ region of the vehicle, at the bottom of the windscreen4. The spigot24is located on the central longitudinal axis25of the base member9, is cylindrical in form, and extends upwardly at an acute angle26(optionally 45°) to the longitudinal axis25so that an end surface27of the spigot is presented towards the proximate forward end of the base member9.

As illustrated most clearly inFIG.6, the spigot24is configured for interaction with the actuator housing11. More particularly, the spigot24is received as a close sliding fit within the lower end of a cylindrical firing chamber28defined inside the actuator housing11.FIG.6shows the actuator housing11in its initial position prior to deployment of the pedestrian protection device, in which the spigot24is substantially fully received within the firing chamber28, and in which a foot plate29of the actuator housing11is received within a cut out region at the forward end of the base member9, between the two side flanges22. The foot plate29of the actuator housing11is generally planar in form, but has a plurality of upstanding and spaced-apart projections30formed thereon.

As also shown inFIG.6, a pyrotechnical actuator31is housed in the upper end of the firing chamber28, and which comprises a pyrotechnic charge32located immediately adjacent the end surface27of the spigot24. The igniter12forms part of the actuator31and may, for example, take the form of a squib. The igniter12is provided within the uppermost end of the firing chamber28, immediately adjacent and operatively connected to the pyrotechnic charge32. The upper end of the firing chamber28is then closed by an end cap33, which may be provided in the form of an electrical connector on the end of the control cable13, and which thereby serves to electrically connect the control cable to13to electrical contacts34on the igniter. As will be appreciated by those of skill in the art, the igniter12may thus be arranged to receive an actuation signal from an electronic controller, via the control cable13and in response to an actuating signal from a sensor configured to detect an impact between the vehicle1and a pedestrian, or the likely occurrence of such an impact, in order to deploy the pedestrian protection device6.

Turning now to considerFIGS.3,5and6in particular, the configuration of the lifter member10will be considered in more detail. The lifter member10is preferably formed from metal such as steel or aluminium, and takes the form of an elongate metal plate. As illustrated inFIG.3, the lifter member10is elongate in form and has a length generally corresponding to the length of the base member9. However, it is to be appreciated that in preferred embodiments of the invention, the lifter member10is actually slightly shorter than the base member9, so as to permit a small degree of longitudinal movement of the lifter member10relative to the base member9without extending past the end of the base member9.

In a general sense, the lifter member10is sized in width to fit between the two side flanges22of the base member9for longitudinal movement therebetween. More particularly, however, the lifter member10has a plurality of outwardly directed guide tabs35which are equi-spaced along each longitudinal side edge of the plate. As illustrated most clearly inFIG.3, the guide tabs35along each side edge are each aligned across the width of the lifter member10with a corresponding guide tab35on the opposite side edge.

As illustrated most clearly inFIG.6, in an initial condition of the pedestrian protection device6prior to deployment, the lifter plate10sits on the uppermost major surface of the base member9, with the guide tabs35of the lifter member10received within respective guide recesses36formed at spaced-apart positions along the side flanges22of the base member9. Each guide recess36is longitudinally positioned between a pair of pivot bores23such that each guide tab35of the lifter member10is located between the lower ends18of an adjacent pair of deformable members14.

The front edge region of each guide tab35is bent upwardly to define a respective upturned lip37at the front end of the guide tab35. In the initial position illustrated inFIG.6, the upturned front lips37of the guide tabs35each rest against a correspondingly angled guide surface38, each guide surface38defining an inclined ramp surface at the front end of each respective guide recess36formed in the flanges22of the base member9.

Turning now to considerFIG.5, which shows the lifter member10somewhat raised relative to the initial position illustrated inFIG.6, it will be observed that the lifter member10is also provided with a plurality of cut-outs along its sides, each cut-out accommodating the lower part of a respective limb16of a deformable member14. More particularly, the rearward end of each cut-out defines a respective contact edge40which is arranged to make contact with and bear against the lower part of a respective said limb16of a deformable member14. In this regard, it is to be noted that in the embodiment illustrated inFIGS.5and6, the lower part of each limb16is provided with notches41formed in its frontwardly and rearwardly directed sides (although only the frontwardly-directed notches41are clearly visible in the figures), with each contact edge40of the lifter member10engaging a respective rearwardly-directed notch41when in the raised position illustrated.

As shown most clearly inFIGS.3and6, the forwardmost end of the lifter member10(i.e. the end corresponding to the spigot-end of the base member9) is bifurcated into a pair of elongate arms42defining an opening43therebetween. The opening is configured to accommodate the actuator housing11and spigot24, such that each arm42extends alongside a respective side of the housing11so as to sit over a respective side region of the foot plate29. The inwardly directed and opposing edges of the arms42are provided with a plurality of spaced-apart notches44which are sized and configured to engage respective projections30on the foot plate29of the actuator housing11.

FIGS.6and7illustrate the pedestrian protection device6in its initial configuration, prior to deployment. In this configuration, the lifter plate10sits on the base member9such that its undersurface rests on the uppermost surface of the base member9. Also, it will be noted that all of the deformable members14occupy initial positions in which they lie substantially flat against the lifter member10, so as to be accommodated entirely below the level of the raised flanges22along each side edge of the base member9, such that they are all received within the base member9. This is facilitated by the tapered form of the deformable members14, which permits them to adopt an initial nested relationship relative to one another in the un-deployed configuration of the device. More particularly, the limbs16of all but one of the deformable members14are received between the limbs of an adjacent deformable member14. This nested arrangement of the deformable members in the initial configuration of the device6allows the device to have a very low profile, thereby permitting convenient installation of the device in the A-pillar region of a motor vehicle, where available space is often limited. Furthermore, it is to be appreciated that in this initial position, in which the deformable members14lie against the lifter member10, the contact edges40of the lifter member10do not engage respective notches41in the deformable members, but instead rest against respective limbs16of the deformable members14, at positions spaced slightly from the notches41.

The trim member7is arranged to fit over the base member9, to cover and house the other components of the device, and is configured in the particular embodiment illustrated to present a generally planar external surface45which, as noted above, may be configured or styled so as to create the impression of being an integral and visually consistent part of the A-pillar of a motor vehicle when installed on the vehicle in the manner described. It is to be appreciated, however, that the external surface45of the trim member45need not be planar and could, for example, be curved or arcuate in other embodiments, in order to match or blend with the external configuration of the A-pillar as required. In other respects, the trim member7comprises an actuator cover46at its forwardmost end, which in preferred embodiments is moulded as an integral part of the trim member7. As illustrated most clearly inFIG.6, the actuator cover46is hollow so as define a cavity which is shaped and configured to receive the actuator housing11, the end cap33, and the end region of the control cable13. The trim member may also comprise a downwardly depending rim in the form of a skirt47which extends around the entire periphery of the trim member, save for a small opening at one end to allow the passage of the control cable13. When the trim member is arranged over the base member9in the initial configuration of the device, the skirt47extends around the periphery of the base member9so as to conceal and protect the internal components of deployment mechanism beneath the trim member7. In this configuration the trim member7and the base member are substantially parallel to one another, with the trim member7being proximal to the base member9.

The deployment of the pedestrian protection device6will now be described with particular reference toFIGS.6-14, noting that:FIGS.6and7show the device in an initial configuration prior to deployment;FIGS.8and9show the device in an initial stage of deployment, shortly after actuation;FIGS.10and11show the device in a subsequent early stage of deployment;FIG.12shows the device in a subsequent mid stage of deployment; andFIGS.13and14show the device in a subsequent substantially fully deployed stage.

Upon receipt of an actuation signal from the sensor within the vehicle1, via the control cable13, the igniter12will fire and thereby detonate the pyrotechnic charge32. The detonating force of the pyrotechnic charge32is directed against the adjacent end surface27of the spigot24inside the firing chamber28, which thus very rapidly and forcefully urges the actuator housing11away from the base member9in a linear manner, guided by sliding movement of the firing chamber28along the spigot24, as illustrated inFIG.8. The foot plate29of the actuator housing11is thus urged upwardly and forwardly relative to the base member10, in a direction parallel to the longitudinal axis of the spigot24.

Due to the above-mentioned engagement between the foot plate29of the actuator housing11and the end arms42of the lifter member10(via the projections30on the foot plate29and the notches44and the arms42), the above-mentioned movement of the actuator housing11is imparted also to the lifter member10, such that the lifter member10is correspondingly urged upwardly and forwardly relative to the base member9by the foot plate29. This upward and forward movement of the lifter member10is guided by upwards sliding movement of the upturned lips37of the guide tabs35along the inclined guide surfaces38of the base member9. The guide tabs35of the lifter member10and the guide recesses36of the base member thus interact along substantially the entire length of the lifter member10to impart the afore-mentioned upward and forward movement to all parts of the lifter member10along its entire length. It is therefore considered preferable for the guide surfaces38of the guide recesses36to be substantially parallel to the longitudinal axis of the spigot24.

As the lifter member10begins to move in the manner described above, its contact edges40serve to urge the limbs16of the deformable members14upwardly, thereby causing an initial degree of pivotal movement of the deformable members14relative to the base member9, about their cranked ends18and in synchronism. As will be appreciated, this upward and pivotal movement of the limbs16of the deformable members14serves to lift the upper ends of the deformable members14, and thereby drive the trim member7away from the base member9as illustrated most clearly in figureFIG.9.

Turning now to considerFIGS.10to12, continued sliding movement of the firing chamber28along the spigot24due to the detonating force of the pyrotechnic charge32serves to urge the lifter member10further upwardly and forwardly away from the base member9, such that the upturned lips37of the guide tabs35slide further up the inclined guide surfaces38. This continued movement of the lifter member10serves to pivotally raise the limbs16of the deformable members14further relative to the base member9, during which the contact edges40slide closer to the notches41. The upper ends of the deformable members40are thus raised further away from the base member9, thereby continuing to drive the trim member7away from the base member9.

As illustrated most clearly inFIGS.11and12, because the deformable members14are all identical to one another (in particular being of identical length) and are pivotally connected to both the base member9and the trim member7in an equi-spaced manner, a parallel motion linkage is provided between the base member9and the trim member7, such that the base member9remains parallel to the trim member7throughout its movement.

Movement of the lifter member10continues in the manner described above, thereby continuing to raise the deformable members14and drive the trim member7further away from the base member9in parallelism, during which the contact edges40continue to slide towards the respective notches41formed towards the lower ends of the limbs16of the deformable members14. As shown inFIG.13, the contact edges40will eventually slide into respective notches41, so to become engaged therein, thereby locking the deformable members14in respective fully raised positions in which they extend substantially perpendicular to both the base member9and the trim member7, as shown inFIG.14. It is to be appreciated, however, that in variants of the described embodiment the fully deployed positions of the deformable members could be a short degree past the position in which they are exactly perpendicular to the base member9, in a so-called ‘over-dead-centre’ manner. In this condition, the trim member7is located in a fully deployed position in which it is spaced maximally from the base member9so as to define a significant gap8therebetween, with the deformable members14extending across the gap8.

Turning now to considerFIGS.15and16, aspects of an alternative embodiment are illustrated in which the notches41of the above-described deformable members14are replaced with flattened portions41aof the wire limbs16. Also, in this embodiment it will be noted that the contact edges40aare arcuate and define part of respective recesses45which are sized and shaped to receive the flattened portions41aof the wire limbs16in a close sliding fit when the lifter member10aand the deformable members14approach and adopt their respective deployed positions as illustrated inFIG.16.

Turning now to considerFIGS.17and18, aspects of an alternative embodiment are illustrated in which the device's actuator arrangement has a somewhat different configuration to that of the previously described embodiments. Specifically, in this arrangement, the firing spigot24of the base member9extends generally parallel to the longitudinal axis25of the base member9, rather than at an acute angle as in the case of the embodiment shown inFIGS.3,6,8and10. Nevertheless, the firing spigot24of this arrangement is again cylindrical in form and is again received as a close sliding fit with the end of a cylindrical firing chamber (not shown) defined inside an actuator housing11. However, as illustrated inFIGS.17and18, in this embodiment the actuator housing11itself is generally cylindrical in form, and thus presents a somewhat lower profile relative to the base member9than is the case in the previously described embodiments. This may permit more convenient packaging of the device in some motor vehicles.

Although not shown inFIGS.17and18, a pyrotechnic charge is provided inside the firing chamber, immediately adjacent the end surface of the spigot24, in a substantially identical manner to that described above with reference toFIG.6.

The end of the actuator housing11which is opposite to the end into which the firing spigot24extends is provided with an actuating ramp48which is inclined at an acute angle (optionally 45°) to the longitudinal axis25of the base member9. Additionally, in this arrangement, the lifter member10is provided with an upturned guide tab49which is arranged to bear against the lower region of the actuating ramp48in the pre-actuation condition of the device as illustrated inFIG.17.

In the arrangement ofFIGS.17and18, denotation of a pyrotechnic charge (not shown) provided inside the firing chamber gives rise to a force which is directed against the adjacent end surface of the firing spigot24, which thus very rapidly and forcefully urges the actuator housing11and its actuating ramp48away from and along the spigot24, in a direction generally parallel to the axis of the base member9, as illustrated by the arrow inFIG.17. The actuating ramp48is thus driven underneath the guide tab49, such that the guide tab49is caused to ride up the surface of the actuating ramp, thereby urging the end of the lifter member10upwardly as shown inFIG.18. As will be appreciated, upward and forward movement of the lifter member10arises due to upwards sliding movement of the upturned lips37of the guide tabs35along the inclined guide surfaces38of the base member9, in the same manner as described above in connection with the preceding embodiments. The guide tabs35of the lifter member10and the guide recesses36of the base member thus interact along substantially the entire length of the lifter member10to impart the afore-mentioned upward and forward movement to all parts of the lifter member10along its entire length.FIG.19is a schematic illustration showing the pedestrian protection device of the present invention (and specifically the arrangement described above in relation toFIGS.3to14) in its fully deployed position in which the trim member7is spaced from the base member9by the deformable members14so as to define a gap8between the trim member7and the base member9, which will be securely mounted to the A-pillar of the motor vehicle when installed in the vehicle. Reference number46denotes the head of a pedestrian who has been struck by the vehicle and thrown over the vehicle's hood towards the A-pillar such that the head46is about to strike the deployed trim member7. As will be seen, in the deployed configuration of the device6, the deformable members14are positioned so as to serve as struts acting in compression to support the trim member7in its deployed position.

FIG.20illustrates the arrangement at a subsequent stage of the accident, a few milliseconds afterFIG.19, and shows the pedestrian's head46having struck the trim member7. The inertia of the pedestrian's head46causes deflection of the plastic trim member7as shown, which will serve to absorb a small amount of impact energy and slightly slow the movement of the pedestrian's head46towards the supporting A-pillar. As the occupant's head continues to move towards the underlying A-pillar behind the base member, the deformable members14begin to buckle and, due to their rigid metal wire construction, thereby absorb significant impact energy via plastic deformation, which in turn serves to more significantly decelerate the occupant's head and slow its movement towards the underlying A-pillar.

FIGS.21and22illustrate respective successive stages of impact with the pedestrian's head46, and show extensive buckling of the deformable members14.FIG.22illustrates the device having absorbed substantially all of the impact energy, with the deformable members14very significantly deformed, thereby substantially stopping movement of the pedestrian's head towards the A-pillar. The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for obtaining the disclosed results, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Throughout this specification, including the claims which follow, unless the context requires otherwise, the words “have”, “comprise”, and “include”, and variations such as “having”, “comprises”, “comprising”, and “including” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The words “preferred” and “preferably” are used herein to refer to embodiments of the invention that may provide certain benefits under some circumstances. It is to be appreciated, however, that other embodiments may also be preferred under the same or different circumstances. The recitation of one or more preferred embodiments therefore does not mean or imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, or from the scope of the claims.