GB2582130A

GB2582130A - A vehicle airbag component

Info

Publication number: GB2582130A
Application number: GB1902713.5A
Authority: GB
Inventors: Feng Bill; Peter Brown Richard; Szavo Miklos; Allan Graham
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2019-02-28
Filing date: 2019-02-28
Publication date: 2020-09-16
Anticipated expiration: 2039-02-28
Also published as: GB201902713D0; GB2582130B

Abstract

A vehicle airbag component comprises an airbag 48 configured to be deployed from a seatbelt 30 of a vehicle such that, when inflated, the airbag comprises a recessed region 60 configured to receive the head 54 of a vehicle occupant 26 wearing the seatbelt. The recessed portion may be at least partially defined by two elongate portions 62a,b forming a V-shape, Y-shape, U-shape or X-shape, and may act to resist rotation and lateral displacement of the head. The airbag component may comprise a seatbelt engaging portion such as a receptacle for accommodating the airbag prior to inflation. The receptacle may form part of a sleeve which is movable with respect to the seatbelt. The airbag may be inflated in situations such as when the occupant is judged to be too far from a dashboard airbag (figures 4-6), such as when in an autonomous driving position, for the dashboard airbag to be properly effective, with a control system (figures 9, 10) taking into account the occupant’s position before deciding whether to deploy the airbag.

Description

A VEHICLE AIRBAG COMPONENT

TECHNICAL FIELD

The present invention relates to a vehicle airbag component. The invention also relates to an occupant restraint system comprising a vehicle airbag component and a control system for controlling operation of the airbag component. The invention also relates to a vehicle comprising the occupant restraint system and/or the airbag component.

BACKGROUND

Vehicle airbags are arranged to provide effective deceleration of a vehicle occupant when the occupant is seated in a conventional position. In general, the occupants of a vehicle are generally seated facing forward so that the driver, for example, can safely drive the vehicle. In the event of a frontal collision, a steering wheel mounted airbag deploys in a rearward direction towards the occupant so that the airbag can accommodate the forward motion of the driver's head and body relative to the steering wheel.

Steering wheel mounted airbags are arranged so that they provide protection for the driver in circumstances where the driver is seated where they can operate the vehicle's controls.

However, it is envisaged that in future vehicles there may be situations in which a vehicle occupant may be seated in a non-conventional position whilst the vehicle is moving, such as with autonomous vehicles, which do not require the driver to be in control of the vehicle at all times. In these situations, the vehicle occupants may be allowed to have the freedom to move their seats into a variety of different positions when the driver is not required to be in control of the vehicle. For example, a driver may choose to be seated at an increased distance from the steering wheel. In such circumstances, a steering wheel mounted airbag may be less effective in supporting the head and torso of the driver during a collision.

It is an aim of the present invention to address the disadvantages associated with the known occupant restraint systems.

SUMMARY OF INVENTION

According to an embodiment of the invention there is provided a vehicle airbag component comprising an airbag configured to be deployed from a seatbelt of a vehicle. The airbag is configured such that, when inflated, the airbag comprises a recessed region configured to receive the head of a vehicle occupant wearing the seatbelt.

The recessed region of the airbag can be arranged such that, when in use, it resists the forward motion of the vehicle occupant. Hence, the seatbelt airbag is arranged to achieve earlier deceleration of the occupant than would be possible with a conventional occupant restraint system. In addition, the characteristically recessed shape of the recessed region enables the airbag to conveniently restrict any lateral and/or rotational movement of the occupant's head.

The recessed region may be at least partially defined by an elongate portion arranged to engage with the occupant's head during a vehicle collision. The elongate portion advantageously increases the effect of the seatbelt airbag in resisting rotation and lateral displacement of the occupant's head as it decelerates, which thereby reduces the strain on the occupant's neck muscles during the collision, and reduces the lateral acceleration of the head during a collision. The vehicle airbag may comprise at least two elongate portions at least partially defining the recessed region, the recessed region being configured to receive the occupant's head substantially between the elongate portions. The at least two elongate portions advantageously resist rotation and lateral displacement of the occupant's head in two directions.

The airbag may comprise a central portion arranged between the at least two elongate portions, the central portion being arranged to receive a front portion of the occupant's head during a vehicle collision. The elongated portions support the sides of the occupant's head and direct the front portion of the occupant's head onto the central portion of the airbag, which is arranged to resist the forward motion of the occupant as they decelerate.

The airbag may comprise at least one of a V-shape, a Y-shape, an X-shape and a U-shape.

According to a further aspect of the present invention, there is provided an occupant restraint system for a vehicle. The system comprises a vehicle airbag component according to the above aspect and a seatbelt being arranged, when in use, to be at least partially arranged across a vehicle occupant's torso. The airbag component comprises a seatbelt engaging portion arranged to attach the airbag to the seatbelt.

The seatbelt engaging portion of the airbag component may comprise a receptacle for accommodating the airbag when in a pre-inflated state, the receptacle being integrally formed with the seatbelt. The receptacle may form an integral part of a sleeve attached to the seatbelt. The sleeve may be movable with respect to the seatbelt.

The system may comprise an airbag inflator configured to inflate the airbag in the event of a vehicle collision, and a control system for controlling operation of the airbag inflator, the control system comprising: an input arranged to receive an input signal indicative of an occupant's position within the vehicle; a processor arranged to determine a control signal for controlling the operation of the airbag inflator in dependence on the input signal; and an output arranged to output the control signal to the airbag inflator.

The control system is arranged to control the operation of the seatbelt airbag so that the seatbelt airbag deploys when the occupant is deemed to be arranged in a position in which it is safe to deploy the seatbelt airbag. The control system may be arranged to control the extent of the airbag seatbelt deployment in dependence on the position of the occupant, thereby ensuring that there is sufficient space in which to deploy the seatbelt airbag such that its deployment does not cause injury to the occupant.

The control system may be arranged to receive an input signal indicative of a position of at least one movable component of a seat assembly of the vehicle, the processor being configured to control deployment of the airbag in dependence on the position of the at least one movable component of the seat assembly. The control system is advantageously configured to determine an occupant's position from the position and/or arrangement of their seat with respect to a primary airbag. From this information, the control system may be arranged to determine whether there is sufficient space in which to deploy the seatbelt airbag safely.

The processor may be configured to prevent the airbag from deploying in the event that the at least one movable seat component is in a range of movement. The range of movement may relate to a plurality of positions in which the at least one movable seat component may be arranged by an occupant of the seat. The range of movement may define a distance, or separation, of the occupant with respect to a primary airbag which is deployed from a steering wheel of the vehicle.

The input signal may comprise information relating to the at least one movable seat component being rotated and/or longitudinally translated relative to another component of the seat assembly.

The input signal may comprise information relating to the operation of a control means operable to move the at least one movable seat component.

According to a further aspect of the present invention, there is provided a vehicle comprising the airbag, or the occupant restraint system of the above aspects. The vehicle may comprise at least one further airbag arranged to be deployed from an interior surface of a cabin of the vehicle.

It will be appreciated, however, that other arrangements are also useful, and therefore, the present invention is not intended to be limited to any particular arrangement. In any event, the set of instructions (or method steps) described above may be embedded in a computer-readable storage medium (e.g. a non-transitory storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

It will be appreciated that the foregoing represents only some of the possibilities with respect to the particular subsystems of an occupant restraint system, which may be included, as well as the arrangement of those subsystems with the control system. Accordingly, it will be further appreciated that embodiments of an occupant restraint system which include other or additional subsystems and subsystem arrangements remain within the spirit and scope of the present invention. Additional sub-systems may include, for example, systems relating to the operation of a vehicle.

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. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a side-on view of a vehicle including an occupant restraint system according to an embodiment of the invention; Figure 2 shows a side-on view of an occupant seated in a driver position of the vehicle of Figure 1; Figures 3a and 3b illustrate a front and a perspective view, respectively, of a seatbelt airbag according to an embodiment of the invention; Figures 4, 5 and 6 show a plan view of an occupant seated in the driver position of the vehicle of Figure 1, and showing the forward motion of the occupant during a vehicle collision; Figures 7 and 8 show a plan view of an occupant seated in the vehicle of Figure 1, with the vehicle's seat being pivoted about a z-axis of the vehicle, and showing the forward motion of the occupant during a vehicle collision; Figure 9 illustrates a control system according to an embodiment of the invention for controlling the occupant restraint system of Figure 1; and Figure 10 is a flow chart showing the method steps of a control method suitable for controlling the occupant restraint system according to an embodiment of the invention.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and which illustrate specific embodiments of the invention. These embodiments are described in sufficient detail to enable those of ordinary skill in the art to make and use them.

Figure 1 illustrates a vehicle 10, which in this example is an autonomous vehicle that may be capable of driving without manual input from a human driver. In such vehicles an opportunity arises to increase flexibility regarding how the seating may be configured, noting that the dimensions of the driver to steering wheel relationship may be different from those in conventional vehicles. Accordingly, the vehicle 10 is fitted with an occupant restraint system 12 according to the present invention that is adapted to take that seating flexibility into account.

It is noted that occupant restraint systems of the invention may be applicable to any vehicle having a seating arrangement with a high degree of flexibility, an autonomous vehicle being

just one example.

The occupant restraint system 12 comprises a front airbag 14 and a seatbelt assembly 16, which are both electrically connected to a control system 20 of the occupant restraint system 12, the control system 20 comprising one or more controllers.

The seatbelt assembly 16 includes a seatbelt 17 that is arranged to restrain an occupant of the vehicle in their seat as would be understood by a person skilled in the art. The seatbelt assembly 16 also comprises a seatbelt airbag which is arranged to be deployed in the event of a vehicle collision, as shall be described in more detail later.

The front airbag 14 is mounted to a portion of an interior fascia of the vehicle 10 and is configured, when inflated, to resist and control the forward motion of the vehicle occupant during a head-on collision of the vehicle. The control system 20 is arranged to control the operation of the occupant restraint system 12 so as to prevent, or reduce the risk of, injury to the vehicle occupant in the event of a collision.

Figure 2 shows a side-on view of the vehicle 10 with the doors removed to reveal a front passenger cabin 18 of the vehicle 10. The vehicle 10 comprises a cabin floor 22 on which a forward facing seat 24 is mounted in a driver's position. A vehicle occupant 26, or driver, is shown seated in the driver's seat 24 with their torso and head both arranged in a normal upright position.

The occupant 26 is held in their seat 24 by the seatbelt 17 of the seatbelt assembly 16, the seatbelt 17 defining a conventional 'three-point' harness and being divided into a lap belt portion 28 and a shoulder belt portion 30, as is commonly known in the art.

The lap belt portion 28 has an end fitting 32 which, in the illustrated example, is mounted to the cabin floor 22 in a conventional location. The lap belt portion 28 extends from the end fitting 32 across the lap of the occupant 26 to a buckle assembly (not shown), which is mounted to the cabin floor 22 at a conventional location. In alternative examples, the end fitting 32 of the lap belt portion 28 may alternatively be mounted to a vehicle seat frame.

The shoulder belt portion 30 extends from the buckle assembly, across the shoulder of the occupant 26 to a pulley 34 mounted to an upper portion of the cabin interior and then to a retractor mechanism 38, which is mounted at a conventional location at the cabin floor 22. The shoulder belt portion 30 is arranged such that it may be fastened, when in use, across the torso of the occupant 26. Accordingly, the shoulder belt portion 30 may be regarded as defining a 'torso portion' of the seatbelt 17.

The vehicle 10 further comprises an interior fascia, or console 40, having a steering column 42 protruding therefrom. The steering column 42 supports a steering wheel 44 which faces in a substantially rearward direction towards the occupant's seat 24. The front airbag 14 is mounted to the steering wheel 44 and, as such, defines a steering wheel airbag of the occupant restraint system 12. As is conventional, a further front airbag arranged for a front side-passenger of the vehicle 10 may be mounted to a portion of the console 40 that is located directly forward of the passenger's seat.

The front airbag 14 comprises an inflatable bag 46 which is constructed of a suitable fabric. When arranged in a stowed position, the inflatable bag 46 is folded into a stowage compartment in a central hub of the steering wheel 44 (not shown). The front airbag 14 comprises a pyrotechnic airbag inflator, which is arranged in communication with the interior of the bag 46. It will be appreciated by the person skilled in the art that the airbag may be provided with any suitable airbag deployment, or inflation, means without departing from the scope of the invention.

The control system 20 is arranged to energize the airbag deployment means in the event of a frontal collision, the airbag deployment means being configured to rapidly generate a gas that causes the inflatable bag 46 to inflate. As the front airbag 14 is deployed, the inflatable bag 46 emerges from its stowed position within the steering wheel 44 and expands in a substantially rearward direction towards the front facing seat 24. In Figure 2, the airbag 14 is shown in a fully deployed, or activated, condition. The front airbag 14 is also arranged to quickly deflate, soon after its deployment, so as to allow the occupant 26 to regain control of the vehicle 10 or to exit the vehicle 10 safely, once it has stopped.

In addition to the front airbag 14, as already noted a further airbag is also arranged on the seatbelt assembly 16 to define a seatbelt airbag 48 of the occupant restraint system 12. The seatbelt airbag 48 is arranged to co-operate with the front airbag 14 to compensate for a gap that may arise between the occupant and the front airbag 14 if the seat 24 is displaced significantly rearwardly, in order to support the occupant's head during a vehicle collision, as will be explained in more detail below.

With reference to Figure 3a and 3b, the seatbelt airbag 48 is attached, at one end, to the shoulder belt portion 30, which is arranged, when in use, at least partially across the occupant's torso 50. The seatbelt airbag 48 comprises an inflatable component 52, which is configured to deploy, i.e. inflate, in a substantially upward direction towards the head 54 of the occupant 26.

The seatbelt airbag 48 further comprises an airbag inflator (not shown) arranged within the seatbelt engaging portion 56. The inflator is arranged in fluid communication with the interior of the inflatable component 52 as would be commonly understood by the skilled person. The control system 20 is arranged in electronic communication with the seatbelt airbag 48 and is configured to control the airbag inflator to deploy the inflatable component 52 in the event of a collision.

The seatbelt airbag 48 comprises a seatbelt engaging portion 56 which is configured to attach the seatbelt airbag 48 to the seatbelt assembly 16. In particular, the seatbelt airbag 48 is attached to the shoulder belt portion 30 at a point at which inflatable component 52 will be approximately centred over the front portion of the occupant's torso 50 when the belts 28 and 30 are placed about the occupant 26 and buckled in position.

The seatbelt engaging portion 56 comprises a receptacle (not shown) for accommodating the airbag 48 when in a pre-inflated state. The receptacle is formed within a sleeve 58 which is attached to the shoulder belt portion 30. Alternatively, the receptacle may form an integral part of the shoulder belt portion 30 of the seatbelt assembly 16, as would be commonly understood by those skilled in the art. The receptacle, or 'pouch', defines an interior compartment into which the inflatable component 52 of the airbag 48 is packed when in its deflated state. The inflatable component 52 is folded or otherwise packaged into the receptacle so that it readily inflates and expands without impediment in response to gas being supplied into the interior of the bag 52.

The receptacle and the sleeve 58 are each constructed from a suitable material, such as woven nylon fabric or the like.

The sleeve 58 is arranged to surround the webbing of the shoulder belt portion 30.

Alternatively, the sleeve 58 may be stitched or otherwise attached to the shoulder belt portion 30 so as to ensure that the inflatable component 52 of the airbag 48 maintains a constant position relative to the seatbelt assembly 16. Accordingly, the seatbelt engaging portion 56 of the airbag 48 is securely attached to the shoulder belt portion 30 so as to ensure that it is correctly positioned in front of the occupant's head 54 and torso 50 when worn, and does not slide longitudinally along the shoulder belt portion 30. Alternatively, the sleeve 58 may be movable with respect to the seatbelt assembly 16 to allow the seatbelt airbag 48 to be adjusted to suit different sized vehicle occupants.

The seatbelt airbag 48 is shown in Figures 3a and 3b as being attached to the shoulder belt portion 30, which ensures that the inflatable portion 52 is arranged, when inflated, directly in front of the occupant's head and torso. The inflatable portion 52 of the seatbelt airbag 48 forms an energy absorbing cushion between the occupant 26 and, in the illustrated example, the driver's airbag 14. In this way, the seatbelt airbag 48 is arranged to protect the occupant's torso 50 and head 54 in the event of collision, thereby preventing or reducing injury to the occupant 26.

The seatbelt airbag 48 is particularly advantageous in situations where the occupant 26 is seated further away from the front airbag 14 of the occupant restraint system 12 than is the case in the nominal driving position. This may be preferable, for example, in autonomous vehicles which do not require the driver to operate the vehicle while it is in motion. Advantageously, the seatbelt airbag 48 is configured so that its inflatable portion 52 is arranged between the occupant 26 and the front airbag 14. In this way, the seatbelt airbag 48 bridges the gap between the occupant 26 and the front airbag 14. The arrangement of the seatbelt airbag 48 enables the restraint system 12, in the event of a collision, to resist a greater proportion of the occupant's forward motion than would be possible with the front airbag 14 alone.

The seatbelt airbag 48 is shown in Figures 3a and 3b in a deployed condition. As visible in these figures, the inflatable component 52 comprises a first elongate portion 62a and a second elongate portion 62b that extend upwardly and away from a central portion 64 arranged therebetween. The central portion 64 connects the extended portions 62a, 62b to the seatbelt engaging portion 56 to define a substantially Y-shaped inflatable component 52 of the seatbelt airbag 48. In this way, the first and the second elongate potions 62a, 62b define two upwardly facing arms of the Y-shaped inflatable component 52.

The region between the first and the second elongate potions 62a, 62b defines a recessed region 60, which is configured to receive the head 54 of the vehicle occupant 26 during a vehicle collision, while the elongate portions 62a, 62b extend, at least partially, around the occupant's head to provide side cushioning and resistance to rolling or turning about any of the three x, y and z head axes when the occupant faces directly forwards. In particular, the inflated central portion 64, being arranged between the two elongate portions 62a, 62b, is suitably configured to receive and accommodate a front portion of the occupant's head 54 during a vehicle collision.

Although the inflatable component 52 is described herein with a substantially Y-shaped configuration, the inflatable component 58 may comprise any suitably configured shape which provides support for occupant's head 54 during a vehicle collision. In alternative embodiments of the present invention, the seatbelt airbag comprises any one of a V-shaped, a Y-shaped, an X-shaped and a U-shaped inflatable component.

Figures 4, 5 and 6 show a top-down view of an occupant 26 seated in the driver's seat 24 of the vehicle 10. Figure 4 shows the occupant restraint system 12 in a pre-deployed condition, whereas Figures 5 and 6 show the occupant restraint system 12 in a post-deployed condition. The transition from Figure 4 to Figure 6 illustrates the forward inertial motion of the occupant 26 which is caused by a predominately longitudinal or oblique frontal collision.

With particular reference to Figure 4, the occupant 26 is seated in a conventional, upright manner, with the seatbelt assembly 16 restraining the occupant's torso 50 against the back of the seat 24. However, unlike with a conventional driving position, the seat 24 is displaced rearwardly and horizontally to the extent that the occupant 26 is unable to reach the steering wheel 44. As explained previously, such a scenario may arise in autonomous vehicles, which do not require the driver to be in control of the vehicle 10 while it is in motion.

Figure 5 and Figure 6 illustrate the occupant restraint system 12 in a deployed state during the moments that immediately follow a vehicle collision. A typical frontal vehicle collision may lead to a time difference between the conditions shown in Figure 4 and Figure 5 as being between 20ms and 40ms. The subsequent timing difference between the conditions shown in Figures 5 and 6 would be in the range 5ms to 15ms.

It will be appreciated by a person skilled in the art that the difference in time between the conditions, as shown in Figures 4 to 6, would be dependent on the nature and severity of any given collision. It will also be appreciated that the arrangement and operation of the airbag according to the present invention is relevant to a range of different collision conditions and timings.

The front airbag 14 and the seatbelt airbag 48 are both deployed in response to the sudden deceleration of the vehicle 10, which is caused by the predominantly longitudinal or oblique frontal collision. The occupant's inertia causes their head 54 and torso 50 to move towards the console 40, or steering wheel 44. The lap belt portion 28 restrains the occupant 26 at the base of their torso, which causes their torso 50 and head 54 to pivot, about the lap belt portion 28, in a progressively forward motion towards the steering wheel 44, as shown in Figures 5 and 6.

The occupant 26 is shown, in Figure 5, just before their head 54 makes contact with the inflatable portion 52 of the seatbelt airbag 48. A few moments later, the occupant 26 is driven into the seatbelt airbag 48 by their forward momentum, as shown in Figure 6, and the inflatable portion 52 receives and accommodates the occupant's head 54 between its two elongate portions 62a, 62b. Accordingly, the part 64 of the seatbelt airbag 48 is arranged to resist the forward motion of the occupant 26 before they reach the front airbag 14, thereby achieving earlier deceleration of the occupant 26 than would be possible with a conventional occupant restraint system 12. In addition, the shaping of the recessed region 60 of the inflatable portion 52 ensures that it restricts lateral and rotational movement of the head 54. In this way, the elongate portions 62a, 62b increase the effect of the seatbelt airbag 48 in resisting rotation and lateral displacement of the occupants head as it decelerates, which thereby reduces the strain on the occupant's neck muscles during the collision, and reduces the lateral acceleration of the head during a collision.

Figures 7 and 8 illustrate a head-on vehicle collision in which the occupant's seat 24 is pivoted, in a clockwise direction, about a vertical axis of the vehicle 10 towards the centre of the vehicle. Figure 7 shows the occupant restraint system 12 in a pre-deployed condition with the occupant 26 seated in a conventional upright manner, but with their torso 50 and head 54 facing at an angle relative to a centre line of the steering wheel 44 (as depicted by the dotted line X).

During the collision, the occupant's inertial motion is directed in substantially the direction of travel of the vehicle 10 prior to the collision, which for a head-on collision is generally parallel with a longitudinal axis of the vehicle 10. In particular, the occupant's inertia causes their head 54 and torso 50 to move towards the console 40 along the centre axis (i.e. dotted line X) of the steering wheel 44. As the occupant faces at an angle relative to a centre line of the steering wheel 44 in this example, in the event of a collision they will meet the front and seatbelt airbags 46, 48 at an angle. In the absence of the seatbelt airbag 48, the occupant could roll or slide across the rearward facing surface of the front airbag 14, causing less than optimal interaction of the occupant with the airbag, which could cause injury to the occupant.

To address this, the seatbelt airbag 48 is arranged to make initial contact with the front and the left side portion of the occupant's head 54 in this scenario, as shown in Figure 8. In particular, an inner facing portion of the second elongate member 62b is arranged, in its inflated state, to support the left side of the occupant's head 54. The shape of the inflatable portion 52 thereby prevents the occupant's head 54 from sliding, or rolling, around the side of the seatbelt airbag 48. The seatbelt airbag 48 therefore ensures that the forces that are exerted upon the head 54 and torso 50 by both seatbelt airbag 48 and the front airbag 14 are directed, primarily, towards resisting the lateral and rotational motion of the occupant's head, despite the occupant 26 having an off-centre alignment relative to the direction of the collision.

The inflatable elongate portions 62a, 62b are also arranged to support the head 54 by preventing the occupant from being deflected by the deployment of the front airbag 14 in a substantially lateral direction.

The examples described above, with reference to Figures 4 to 8, are representative of the effect of the seatbelt airbag 48 when employed in an occupant restraint system 12 of a vehicle 10. It will be appreciated by a person skilled in the art that the seatbelt airbag according to the present invention would exhibit similarly advantageous affects in alternative collision scenarios, other than those described herein.

The vehicle seat may be adjusted by numerous means such that an occupant 26 may be arranged in a variety of non-conventional positions with respect to the front airbag 14. For example, a typical vehicle seat may be translated in a longitudinal direction relative to the length of the vehicle 10. Alternatively, the seat may be pivoted or rotated about a substantially vertical axis (as shown in Figure 8). The seat may also be pivoted about a horizontal axis of the vehicle. The backrest of the seat may be reclined and/or its height may be raised or lowered according to an occupant's preference. Alternatively, the steering column 42 may be extended or retracted, relative to the console 40, which thereby affects the distance between the occupant 26 and a front airbag 14 mounted in the steering wheel 44.

As explained above, the seatbelt airbag 48 according to the present invention is particularly advantageous in situations where the occupant is arranged in a non-conventional seating position. However, there may be situations, such as when the driver is directly operating the controls of the vehicle, where it may be preferable to inhibit deployment of the seatbelt airbag 48. The control system 20 of the occupant restraint system 12 is arranged to control when to deploy the seatbelt airbag 48 so as to provide optimum support for the vehicle occupant 26, in the event of a vehicle collision.

As explained previously, with reference to Figures 1 and 2, the seatbelt airbag 48 and the front airbag 14 comprise a separate airbag inflator configured to inflate each airbag in the event of a vehicle collision. A specific configuration and operation of the control system 20, according to the present invention, will now be described with reference to Figures 9.

The control system 20 comprises an input 66 arranged to receive an input signal indicative of an occupant's position within the vehicle 10. This 'occupant position' signal 76 may comprise information relating to the position of a movable component of the seat 24 relative to the vehicle or to another seat component. The control system 20 could also be configured to receive a signal indicative of the weight and/or size of the occupant. The input 66 is also arranged to receive a further input signal indicative of a demand for the seatbelt airbag 48 to deploy. This further input signal defines an airbag demand, or trigger, signal 74 which may comprise sensor information relating to a detected vehicle collision, as would be commonly understood by those skilled in the art.

The control system 20 further comprises at least one processor 68 arranged to determine a first airbag control signal Ma for controlling the deployment, or inflation, of the seatbelt airbag 48 in dependence on the input signals. Similarly, the control system 20 may also be arranged to generate a second airbag control signal 78b to control the deployment of the front airbag 14.

The processor 68 is further connected to a memory 72, of the control system 20, which is arranged to store data and/or a set of instructions for controlling the operation of the control system 20, according to an embodiment of the invention. Accordingly, the processor 68 accesses the data and/or instructions stored in the memory 72 to enable it to determine each airbag control signal.

The control system 20 includes an output 70 arranged to output the first and second airbag control signals 78a, 78b to the seatbelt airbag 48 and the front airbag 14, respectively. In particular, the output 70 is arranged in communication with the airbag inflator of each airbag 14, 48, the airbag inflator being configured to receive the control signals 78a, 78b that are outputted thereto.

The occupant position input signal 76 may comprise, for example, a signal output by a seat sensor providing an indication of the position of the seat 24.

Alternatively, or in addition, the occupant position input signal may include a copy of seat control instructions, which are used by another control system to control operation of an electrically powered actuator (or motor) of the seat 24 to move the seat 24 between positions, and from which the position of the seat may therefore be derived. Such seat control instructions typically comprise current/voltage information corresponding to the operation of the electric seat actuator. The voltage values are generated by a separate seat control system, as would be commonly understood by those skilled in the art. The seat control instructions are delivered to the seat actuator in the form of an electronic signal which is monitored by the control system 20. The seat actuator, itself, is a control means operable to adjust a movable seat component in dependence on the seat control signal. In particular, the seat control information relates to the rotation, reclining and/or longitudinal translation of the movable seat component relative to another component of the seat 24.

The processor 68 is arranged to control the deployment of the seatbelt airbag 48 in dependence on the position of the movable seat component. In particular, the processor 68 is configured to prevent the seatbelt airbag 48 from deploying if the movable seat component is within a pre-determined range of positions. The pre-determined positions may correspond to the movable seat component being located such that there would be insufficient space between the front airbag 14, when inflated, and the occupant 26 in which to effectively deploy the seatbelt airbag 48. In other words, the processor 68 prevents unnecessary deployment of the seatbelt airbag 48 at times when the seat 24 is positioned such that the front airbag 14 is capable of providing sufficient protection to the occupant without assistance, as in a conventional vehicle.

Conversely, the processor 68 acts to ensure that the seatbelt airbag 48 does deploy when the indicated position of the seat 48 is outside the pre-determined range of positions, which entails a gap between the occupant 26 and the front airbag 14 that must be compensated for to protect the occupant 26 fully.

A method 80 of operating the control system 20 according to an embodiment of the invention will now be described in more detail with reference to the flow chart of Figure 10.

The control method 68 starts with a first step 82 in which the input 66 receives the airbag demand signal 74 indicative of a need to deploy the seatbelt airbag 48. The airbag demand signal 74 comprises information relating to a detected vehicle collision, which is sent to the control system 20 from a suitably arranged sensor means, as would be readily understood by a person skilled in the art.

In a second method step 84, the input 66 receives an occupant position signal 76 comprising seat control instructions for controlling a seat actuator, which is arranged to adjust a movable component of the seat 24.

A third method step 86 comprises the processor 68 determining whether to deploy the seatbelt airbag 48 in dependence on the occupant position signal 76. According to the exemplary method, the processor 68 first determines the position of the movable seat component from the occupant position signal 76 and then compares it against a pre-determined range of positions, which are stored in a lookup table on the memory 72 of the control system 20. The pre-determined range of positions may correspond to a set of seat configurations which result in there being insufficient space between the front airbag 14, when inflated, and the occupant 26 in which to effectively deploy the seatbelt airbag 48.

The control system 20 is arranged to receive multiple occupant position signals 76 comprising information relating to a plurality of movable seat components of the seat 24. The occupant position signal 76 may also comprise information relating to the position of the steering wheel 44, relative to the seat 24 and/or console 40 of the vehicle 10. The position of each movable seat component, and/or the steering wheel, may be compared against a separate predetermined range of positions stored in the memory 72 of the control system 20, and may be used to determine whether the seatbelt airbag 48 can be deployed effectively.

If the movable seat component is determined to be within the pre-determined range of positions, then the processor 68 will not issue a command to deploy the seatbelt airbag 48. In this case, the control method resets to the beginning and waits to receive the next airbag demand signal 74.

If the movable seat component is not within the pre-determined range, the processor 68 determines that there is sufficient separation between the front airbag 14 and the occupant 26 to deploy the seatbelt airbag 48. In this case, the control method proceeds to a fourth method step 88 in which the processor 68 determines a first airbag control signal 80 for controlling the airbag inflator of the seatbelt airbag 48. The first airbag control signal 78a comprises instructions to energize the airbag inflator upon receiving the first airbag control signal. The processor 68 also determines a second airbag control signal for controlling the operation of the front airbag 14.

In a final step 90, the output 70 of the control system 20 is arranged to output the first and second airbag control signals 78a, 78b to the airbag inflators of the seatbelt airbag 48 and front airbag 14 respectively. The airbag inflator of the seatbelt airbag 48 is arranged to inflate and so deploy the inflatable portion 52 of the airbag 48 upon receiving the first airbag control signal 78a.

It will be appreciated that the occupant restraint system 12 may comprise a plurality of passenger airbags. Each of the plurality of airbags may be connected to, and controlled by, the control system 20 according to the present invention. Such passenger airbags may include side airbags, curtain airbags and knee airbags, etc. Furthermore, the seatbelt airbag 48 according to the present invention may be attached to the seatbelt assembly 16 at a number of suitable locations, without departing from the scope of the present invention. For example, in embodiments of the invention, the seatbelt airbag 48 may be attached to the lap belt portion 28 of the seatbelt assembly 16. Alternatively, the seatbelt airbag 48 may be arranged so that, when inflated, it is configured to protect the side of the body of the occupant in order to provide protection against side impacts or impacts from other directions.

Alternative embodiments of the occupant restraint system 12 may employ a plurality of seatbelt airbags 48 attached at various points along the seatbelt assembly 16 to provide protection against impacts from multiple directions. The use of multiple seatbelt airbags beneficially increases the resolution of the arrangement and therefore its ability to respond to a range of scenarios appropriately, for example by activating a subset of the seatbelt airbags in accordance with an indicated gap between the occupant and the front airbag 14.

The occupant restraint system 12 may be mounted in any vehicle having suitable accommodation for passengers, such as, for example, a truck, an aircraft, a train, or the like.

It will also be appreciated that suitable connection apparatus may be provided to interconnect the control system 20 and the various components of the occupant restraint system 12. The interconnections may be direct or 'point to point' connections, or may be part of a local area network (LAN) operated under a suitable protocol (CAN-bus or Ethernet for example). Also, it should be appreciated that rather than using cabling, the control commands may be transmitted wirelessly over a suitable wireless network, for example operating under WiFiTM or Zig BeeTm standards (IEEE802.11 and 802.15.4 respectively).

Claims

CLAIMS1. A vehicle airbag component comprising an airbag configured to be deployed from a seatbelt of a vehicle, the airbag configured such that, when inflated, the airbag comprises a recessed region configured to receive the head of a vehicle occupant wearing the seatbelt.
2. A vehicle airbag component according to claim 1, wherein the recessed region is at least partially defined by an elongate portion arranged to engage with the occupant's head during a vehicle collision.
3. A vehicle airbag component according to claim 2, comprising at least two elongate portions at least partially defining the recessed region, the recessed region being configured to receive the occupant's head substantially between the elongate portions.
4. A vehicle airbag component according to claim 3, wherein the airbag comprises a central portion arranged between the at least two elongate portions, the central portion being arranged to receive a front portion of the occupant's head during a vehicle collision.
5. A vehicle airbag component according to any one of claims 1 to 4, wherein the airbag comprises at least one of a V-shape, a Y-shape, an X-shape and a U-shape.
6. An occupant restraint system for a vehicle, the system comprising: a vehicle airbag component according to any one of the preceding claims; and a seatbelt being arranged, when in use, to be at least partially arranged across a vehicle occupant's torso; wherein the airbag component comprises a seatbelt engaging portion arranged to attach the airbag to the seatbelt.
7. An occupant restraint system according to claim 6, wherein the seatbelt engaging portion of the airbag component comprises a receptacle for accommodating the airbag when in a pre-inflated state, the receptacle being integrally formed with the seatbelt.
8. An occupant restraint system according to claim 6, wherein the seatbelt engaging portion of the airbag component comprises a receptacle for accommodating the airbag when in a pre-inflated state, the receptacle forming an integral part of a sleeve attached to the seatbelt.
9. An occupant restraint system according to claim 8, wherein the sleeve is movable with respect to the seatbelt.
10. An occupant restraint system according to any of claims 6 to 9, the system comprising an airbag inflator configured to inflate the airbag in the event of a vehicle collision, and a control system for controlling operation of the airbag inflator, the control system comprising: an input arranged to receive an input signal indicative of an occupant's position within the vehicle; a processor arranged to determine a control signal for controlling the operation of the airbag inflator in dependence on the input signal; and an output arranged to output the control signal to the airbag inflator.
11. An occupant restraint system according to claim 10, wherein the control system is arranged to receive an input signal indicative of a position of at least one movable component of a seat assembly of the vehicle, the processor being configured to control deployment of the airbag in dependence on the position of the at least one movable component of the seat assembly.
12. An occupant restraint system according to claim 11, wherein the processor is configured to prevent the airbag from deploying in the event that the at least one movable seat component is in a range of movement.
13. An occupant restraint system according to claim 11 or claim 12, wherein the input signal comprises information relating to the at least one movable seat component being rotated and/or longitudinally translated relative to another component of the seat assembly.
14. An occupant restraint system according to any one of claims 11 to 13, wherein the input signal comprises information relating to the operation of a control means operable to move the at least one movable seat component.
15. A vehicle comprising the airbag according to any one of claims 1 to 5, or the occupant restraint system according to any one of claims 6 to 14.
16. A vehicle according to claim 15, comprising at least one further airbag arranged to be deployed from an interior surface of a cabin of the vehicle.