GB2639181A

GB2639181A - Crash protection structure

Info

Publication number: GB2639181A
Application number: GB2403152.8A
Authority: GB
Inventors: Millera Grau David; Sedgwick Andrew; Logue Steven; Vernet Mickael
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2024-03-05
Filing date: 2024-03-05
Publication date: 2025-09-17
Also published as: WO2025185991A1; WO2025185991A8; GB202403152D0

Abstract

A crash protection structure 100 for coupling to a vehicle frame (11, figure 2) comprises: a support structure 102 to be coupled to the vehicle frame at a first coupling point (132), the support structure comprising an engagement surface 122 abutting a corresponding engagement surface 123 of the vehicle frame and coupled to an electric drive unit 200; and a tether 110 coupled to the support structure at a second coupling point 134, wherein the tether extends away from the support structure and is coupled to the vehicle frame at a third coupling point 136, wherein the tether maintains a substantially constant distance between the second and third coupling points. The corresponding engagement surface may be aligned with a reinforced section 14a of a vehicle bulkhead 14. The tether may comprise first and second portions (112, 114 figure 4) pivotally coupled (113) to each other. The support structure may comprise a first portion (102a, figure 5) for coupling to the electric drive unit, and a second portion (102b) on which are provided the second coupling point and the engagement surface.

Description

CRASH PROTECTION STRUCTURE

TECHNICAL FIELD

The present disclosure relates to a crash protection structure. Aspects of the invention relate to a crash protection structure and a vehicle.

BACKGROUND

It is known to provide vehicles with protection to avoid injuries being caused to passengers when the vehicle is involved in a collision. Where a vehicle has a front-mounted internal combustion engine, the engine may provide a substantial amount of protection in the case of a frontal collision. For vehicles, such as fully electric vehicles that do not have an internal combustion engine, there is a need to identify an alternative means of protecting passengers during frontal collisions.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a crash protection structure, and a vehicle as claimed in the appended claims.

According to an aspect of the present invention, there is provided a crash protection structure for coupling to a vehicle frame, the crash protection structure comprising: a support structure arranged to be coupled to the vehicle frame at a first coupling point, the support structure comprising an engagement surface arranged to abut a corresponding engagement surface of the vehicle frame and being arranged to be coupled to an electric drive unit; and a tether coupled to the support structure at a second coupling point, wherein the tether extends away from the support structure and is arranged to be coupled to the vehicle frame at a third coupling point, wherein the tether is arranged to maintain a substantially constant distance between the second and third coupling points.

According to another aspect of the present invention, there is provided a tether coupleable to a support structure at a second coupling point, wherein the tether extends away from the support structure and is arranged to be coupled to a vehicle frame at a third coupling point, wherein the tether is arranged to maintain a substantially constant distance between the second and third coupling points. First, second and third are terms used herein to identify different elements and should not be interpreted to imply multiplicity of the elements to which they refer.

Rotation of the support structure relative to the vehicle chassis may occur for example during a frontal impact where the applied force causes the support structure to rotate about the first coupling point. Providing a tether to maintain a substantially constant distance between the support structure and the frame may prevent this rotation. This may allow movement of the support structure to be controlled throughout the crush impact as the assembly deforms. Therefore, the engagement surface of the support structure and the corresponding engagement surface of the vehicle frame may abut more reliably.

The tether may act to maintain a constant straight-line distance between the second and third coupling point or may include a pivot joint to maintain a constant vertical distance between the second and third coupling points. Generally, the tether may be considered as inextensible, although during a collision material deformation may cause the tether to change in length by less than 15%. Generally, the tether may reduce the vertical movement of the support structure. Where the second coupling point moves along an arc, it will be understood that the arc may subtend a relatively small angle and that the support structure may travel a short distance compared to the length of the tether. Vertical movement of the support structure may therefore be considered negligible and may be less than 50mm.

The vehicle frame may comprise a bulkhead, the bulkhead comprising the corresponding engagement surface.

The support structure may comprise a rear end adjacent the bulkhead, the rear end of the support structure comprising the engagement surface.

The bulkhead may separate a passenger compartment from components under the bonnet, and the bulkhead may have stronger portions and weaker portions. If the support structure, or another component, contacts the bulkhead at a weaker portion then ingress into the passenger compartment may be more likely. In this case, the tether may act to direct the support structure towards a stronger portion of the bulkhead, which has the corresponding engagement portion, to help dissipate energy during impact and to reduce the possibility of ingress into the passenger compartment.

The bulkhead may comprise a reinforced portion aligned with the corresponding engagement surface. The distance between the third coupling point and the reinforced portion may be approximately equal to the distance between the third coupling point and the engagement surface.

In this way, the engagement surface and the corresponding engagement surface may abut more reliably due to movement of the support structure relative to the bulkhead during a collision. The tether may pivot about the third coupling point as the support structure translates toward the bulkhead.

The engagement surface may comprise a substantially planar surface.

Providing a planar engagement surface for engaging with the bulkhead evenly may reduce peak stress acting on the support structure and/or bulkhead. The corresponding engagement surface may comprise a substantially planar surface.

The tether may comprise a first member arranged to be coupled to the vehicle frame at the third coupling point and a second member coupled to the support structure at the second coupling point, the first member being pivotably coupled to the second member about a pivot joint.

Providing a tether comprising a pivot joint may improve ease of assembly of the mounting assembly as, for example, the second member may first be coupled to the support structure with the first member in a stowed position before the first member is pivoted to a deployed position to be coupled to the frame. The pivot joint may also provide improved control over the deformation of the tether and/or the mounting assembly during a crushing impact as the tether may pivot at the pivot joint preferentially to buckling at a member.

The first and second members may be arranged to decouple when the engagement surface contacts the corresponding engagement surface.

The tether may be designed to break once the support structure is embedded in the reinforced portion of the bulkhead. This may allow subsequent deformation of other components around the bulkhead, which may help to dissipate energy in the event of a crash. The first member and second member may be arranged to decouple, or the first member and the frame may be arranged to decouple.

In cases of high deformation, the tether may otherwise disengage the engagement surface from the corresponding engagement surface by pivoting about the third coupling point. However, once the engagement surface and the corresponding engagement surface are engaged, friction may maintain the two engagement surfaces in engagement. The tether may therefore decouple to prevent disengagement.

The pivot joint between the first member and the second member may comprise a spring and/or a damper.

A spring or damper may be included to control the characteristics of the pivot joint, for example to increase stiffness of the joint to aid in dissipating energy in the event of a crushing impact. Generally, the pivot joint may comprise a biasing element arranged to bias the first member relative to the second member.

The second coupling point may be proximate the engagement surface.

Coupling the tether to the support structure proximate the engagement portion, and generally at the rear end of the support structure, may allow movement of the support structure, specifically the rear end of the support structure closest the bulkhead to be better controlled.

The engagement surface may be arranged to be spaced apart from the corresponding engagement surface. 30 By spacing the engagement surface from the corresponding engagement surface, less noise generated in the EDU may be transferred into the passenger compartment through the form of vibrations transferred between adjacent abutting components. The spacing of the engagement surface from the corresponding engagement surface may also reduce the prospect of the support structure penetrating the bulkhead as other components of the vehicle may deform in a collision before the support structure contacts the bulkhead. A tether may be particularly beneficial where the engagement surface and corresponding engagement surface are spaced apart, as it may increase the likelihood that contact between the two engagement surfaces occurs during a collision.

The tether may extend downward from the support structure towards the third coupling point.

Upward movement of the rear end of the support structure may be particularly common in collisions and so providing a tether extending downward from the support structure may be desirable to prevent movement of the rear of the support structure upwards, since the tether may be stronger in tension than in compression. This may particularly be the case where the tether comprises two members interconnected by a flexible pivot.

Having a substantially inextensible tether in the upwards direction at least may be beneficial in directing the support structure towards a reinforced portion of the frame and reducing the likelihood of intrusion into the passenger cabin. The pivot between the members of a two part tether may be close to one or other of the second and third coupling points, thereby reducing the capacity of the support structure to deflect downwardly without deformation of the tether in those situations that result in the support structure deflecting downwardly in some collisions.

The support structure may comprise an upper surface, and the tether may engage the upper surface of the support structure.

Providing a tether engaging the upper surface of the support structure may provide a stronger coupling between the tether and support structure, in particular when the support structure moves upwards as the structure collapses. This may reduce the likelihood of the tether decoupling from the support structure and the support structure engaging the bulkhead at a weaker location, leading to intrusion into the cabin.

The support structure may comprise a first portion for coupling to an electric drive unit, and a second portion extending from the first portion. The second coupling point and the engagement surface may be on the second portion.

The second portion may comprise two members extending from the first portion and coupled together by a transverse member. The second coupling point may be on the transverse member.

The second portion may be generally D-shaped and the two members may be spaced apart to allow cables or other ancillary components to pass between them. The arrangement may also provide a good strength while keeping a low weight. The engagement surface may be a surface of the transverse member.

By providing a second portion extending from the first portion, the engagement portion and the corresponding engagement portion may be moved closer together. This may improve the reliability of the engagement between the two engagement portions and may also reduce the prospect of the bulkhead being breached by movement of the electric drive unit.

The crash protection structure may further comprise a first mounting bracket, the first mounting bracket comprising: a body connection point for coupling to a body in white of the vehicle; and a support structure mounting point coupled to the support structure.

The first mounting bracket may provide a simpler means for coupling the support structure to the vehicle frame.

The crash protection structure may further comprise an electric drive unit mounting bracket coupled to the first mounting bracket at the support structure mounting point and an electric drive unit coupled to the electric drive unit mounting bracket.

The bracket may act to couple the support structure to the electric drive unit indirectly, meaning that the support structure does not support the weight of the electric drive unit, allowing the support structure to be made lighter. By coupling the electric drive unit mounting bracket to the first bracket at the support structure mounting point, a single fastener for example may be used to couple together the first bracket, the electric drive unit mounting bracket and the support structure.

A further aspect of the invention provides a vehicle comprising: a vehicle frame; and a crash protection structure according to the aspect of the invention coupled to the vehicle frame.

The vehicle frame may comprise a deflector panel configured to separate a first internal vehicle volume from a second internal vehicle volume. The tether may be coupled to the deflector panel at the third coupling point.

The deflector panel is arranged to protect traction batteries that may be located behind the deflector panel by deflecting a subframe that may be supporting the electric drive unit down below batteries in crash. The deflector panel may provide a strong and convenient anchor support for the tether.

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 vehicle to provide context for the invention; Figure 2 shows a schematic illustration of a front crash protection structure; Figure 3 shows a schematic illustration of a first front crash protection structure in accordance with the invention; Figure 4 shows a schematic illustration of a second front crash protection structure in accordance with the invention; Figure 5 shows a crash protection frame; and Figure 6 shows a schematic illustration of a third front crash protection structure in accordance with the invention.

DETAILED DESCRIPTION

Figure 1 shows a vehicle 10 to provide context for this invention. The vehicle 10 may be a fully electric vehicle having only an electric machine for propulsion and no internal combustion engine. The vehicle 10 has at least one vehicle drive unit 200 (shown in Figure 2), which may be an electric drive unit. The vehicle drive unit 200 may be an electric drive unit that contains an electric machine and one or more drivetrain components.

The vehicle 10 has a front crash structure 100, which is arranged to protect the passengers of the vehicle during a frontal collision. A frontal collision is any collision where a force is applied to the front of the vehicle. For instance, this may involve the vehicle driving forwardly into a wall or a barrier or another vehicle driving into the front of the present vehicle when the present vehicle is stationary. Crash structures, including one according to the present invention, cannot provide complete protection, however, and their effectiveness depends on the nature and severity of any collision; they may only assist protection of vehicle occupants in a limited number of collisions.

Figure 2 shows a schematic representation of a vehicle drive unit 200 coupled to a vehicle frame 11 and viewed from the front of the vehicle 10. The vehicle 10 comprises the vehicle frame 11 (which may be referred to hereinafter as frame 11) that provides structural support for the vehicle 10 and onto which further vehicle components are mounted. The vehicle frame 11 comprises a plurality of parts permanently coupled together for example using welding, and as such may also be referred to as a body in white 11.

The vehicle frame 11 comprises a portion of the frame 12 which extends generally forward along the vehicle 10. The portion of the body in white 12 may extend along a first and a second side of the vehicle drive unit 200 as shown in Figure 2.

There is provided a support structure 102 to at least partially support the vehicle drive unit 200. The support structure 102 may also be referred to as a crash protection frame 102 or a tray 102. The support structure 102 is coupled to the vehicle frame 11 at a first coupling point 132. As shown in Figure 2, the support structure 102 may be coupled to the vehicle frame 11 using a first mounting bracket 106. By way of non-limiting example, the support structure 102 may be coupled to two first mounting brackets 106. As such, each first coupling point 132 may comprise at least one fastener coupled to each of the first mounting brackets 106 as shown in Figure 2. Each first mounting bracket 106 therefore comprises a support structure mounting point that corresponds with the mounting point 132 of the support structure 102. Each first mounting bracket 106 further comprises one or more body connection points for coupling to the frame 11, optionally the portion of the frame 12 as shown in Figure 2.

The vehicle drive unit 200 may be positioned generally beneath the support structure 102 and may be coupled to the support structure 102 using a drive unit mounting bracket 104. In the embodiment shown in Figure 2, a first side of the drive unit 200 is coupled to a first drive unit mounting bracket 104, and a second side of the drive unit 200 is coupled to a second drive unit mounting bracket 104. The drive unit 200 may be fastened to the drive unit mounting bracket 104 using at least one fastener and may further comprise an insert (not shown) between the drive unit 200 and the drive unit mounting bracket 104. Providing an insert such as a rubber insert may help to reduce the transmission of any vibrations and hence noise from the vehicle drive unit 200 to the drive unit mounting brackets 104 or other components since the rubber may deform to absorb some of the vibrations. The drive unit mounting brackets 104 are also coupled to the first mounting bracket 106, optionally at the support structure mounting point as shown in Figure 2. In this case, the fasteners used may each be used individually to couple together the first mounting bracket 106, the drive unit mounting bracket 104 and the support structure 102. In some cases, four such fasteners may be used on either side of the support structure 102.

The support structure mounting bracket 104 further comprises two rubber bumpers 108 to abut against the drive unit 200 and reduce vibrations transferred from the vehicle drive unit 200 to the support structure 102. Although shown as comprising two rubber bumpers 108 in Figure 2, it will be appreciated that the support structure mounting bracket 104 may comprise any number of rubber bumpers 108.

Figure 3 shows a schematic side view of the crash protection structure 100 coupled to the vehicle frame 11 with the portion of the frame 12 not shown for clarity. Figure 3 shows the vehicle facing right, such that a passenger compartment is on the left side of a bulkhead 14. The support structure 102 comprises an engagement surface 122 arranged to abut a corresponding engagement surface 123 of the vehicle frame 11 once the support structure 102 has moved a predetermined distance relative to the frame 11. This is beneficial in the event of a collision, such as a frontal impact, as the crash protection structure 100 may be allowed to collapse up to a certain level and/or position to dissipate at least some of the energy of the collision. However collapse beyond this certain level and/or position may be prevented or inhibited as the engagement surface 122 abuts the corresponding engagement surface 123. This arrangement may be particularly beneficial where the vehicle drive unit 200 and support structure 102 are provided in an under-bonnet area forward of a passenger cabin in a vehicle. In this case, a frontal collision may otherwise lead to the support structure 102 and/or the drive unit 200 intruding upon the passenger cabin, which needs to be prevented, if possible. The engagement surface 122 may be substantially planar, and the corresponding engagement surface 123 may also be substantially planar such that the engagement surface 122 and the corresponding engagement may fit together. A planar engagement surface 122 may reduce the peak stresses acting on the engagement surface 122 and/or the corresponding engagement surface 123 compared to, for example, a curved or sharp engagement surface, since such a non-planar surface would lead to a higher stress concentration when the engagement surface 122 abuts the corresponding engagement surface 123. The engagement surface 122 and corresponding engagement surface 123 may have any shape where the two engagement surfaces substantially tessellate.

To better control movement of the support structure 102 as the crash protection structure 100 crumples, there is provided a tether 110. The tether 110 is coupled to the support structure 102 at a second coupling point 134 and to the frame 11 at a third coupling point 136. The tether 110 extends away from the support structure 102 and is arranged to maintain a substantially constant distance between the second 134 and third 136 coupling points. It will be understood that some level of deformation of the tether 110 may occur as the crash structure 100 deforms during a collision, but that the variation in distance between the second and third coupling points 134, 136 may reduce due to the presence of the tether. The distance between the second 134 and third 136 coupling points may be measured as the shortest distance between the two points regardless of the direction of each point relative to the other. That is to say that the tether 110 is arranged to rotate as the support structure 102 moves relative to the frame 11, and that the tether 110 maintains a substantially constant total scalar distance between the second 134 and third 136 coupling points, regardless of the orientation of the tether 110. This may allow movement of the support structure 102, preferably movement of the engagement surface 122, to be controlled such that the engagement surface 122 abuts the corresponding engagement surface 123. The second coupling point 134 may follow a circular arc about the third coupling point 136.

In the embodiment shown in Figure 3, the frame 11 comprises a bulkhead 14 arranged to separate a passenger cabin from an under-bonnet area of the vehicle. It is preferable that the under-bonnet area is arranged forward of the bulkhead relative to the forward direction of travel of the vehicle 10, however it will be appreciated that this is not essential. The bulkhead 14 may extend substantially across the width of the vehicle 10 and may be designed so that collapse and intrusion upon the passenger cabin in the event of a collision is inhibited or reduced. The bulkhead 14 comprises the corresponding engagement surface 123, such that the support structure 102 abuts the bulkhead 14 as the crash assembly 100 collapses.

Where the support structure 102 is arranged forward of the bulkhead 14, the support structure 102 comprises a rear end adjacent the bulkhead 14, the rear end comprising the engagement surface 122. Since the tether 110 provides control over the position of the portion of the support structure 102 adjacent the second coupling point 134, it is preferential to couple the tether 110 proximate the engagement surface 122. In the example shown in Figure 3 therefore, the second coupling point 134 is positioned at the rear end of the support structure 102.

It may be preferable to space the engagement portion 132 away from the corresponding engagement portion 123 as shown in Figure 3. This may reduce noise transmitted via vibrations from the electric drive unit 200 and the support structure 102 to the bulkhead 14 and into the passenger cabin. Spacing the engagement portion away from the corresponding engagement portion 123 may also reduce the likelihood of the support structure 102 intruding upon the passenger cabin, as other components within the vehicle 10 may collapse and dissipate energy before the support structure 102 abuts the bulkhead 14.

The bulkhead 14 shown in Figure 3 comprises a reinforced portion 14a that is aligned with the corresponding engagement surface 132. The reinforced portion 14a may be formed as an integral part of the bulkhead 14 or may be a separate component coupled to the bulkhead 14. Since portions of the frame 11 may be designed to not substantially deform during a collision, the third coupling point 136 may not move substantially relative to the reinforced portion 14a of the bulkhead 14. It is therefore beneficial to provide a vehicle frame 11 and crash protection structure 100 such that the distance D1 between the third coupling point 136 and the reinforced portion 14a is approximately equal to the distance D2 between the third coupling point 136 and the engagement surface 122. In this way, the tether 110 may direct the engagement surface 122 towards the reinforced portion 14a of the bulkhead 14 as the crash protection structure collapses. This is due to the reinforced portion 14a of the bulkhead 14 lying on the circular arc which the second coupling point 134 may follow about the third coupling point 136.

The vehicle frame 11 may comprise a deflector panel 18 as shown in Figure 3. The deflector panel 18 is arranged to separate a first internal vehicle volume (not shown) from a second internal vehicle volume (not shown). The crash protection structure 100 is housed at least partially in one of the internal vehicle volumes. The deflector panel 18 extends at least partially across the width of the vehicle such that one of the vehicle volumes is arranged forward relative to the other vehicle volume. By way of non-limiting example, the deflector panel 18 may separate an under-bonnet volume housing the crash protection structure 100 and arranged forward of the deflector panel 18 from a battery storage volume arranged rearward of the deflector panel 18. The deflector panel 18 may be designed to resist substantial deformation in the event of a collision such that the deflector panel 18 is less likely to intrude upon either of the first or second internal vehicle volumes. As shown in Figure 3, the tether 110 may be coupled to the deflector panel 18 at the third coupling point 136. The deflector panel 18 may provide a convenient part of the frame 11 at which to locate the third coupling point 136 of the tether 110, rendering the third coupling point 136 less likely to deflect or be deflected in the event of a collision.

Figure 4 shows a second embodiment of the invention comprising a tether 110 comprising a first member 112 pivotably coupled to a second member 114 about a pivot joint 113. The first member 112 is coupled to the support structure 102 at the second coupling point 134 and the second member 114 is coupled to the frame 11 at the third coupling point 136. Providing the tether 110 as an assembly comprising two members pivotably coupled together may improve ease of assembly of the crash protection structure 100. The first member 112 may be coupled to the support structure 102 with the second member 114 in a stowed position (not shown), rotated about the pivot joint. Once the support structure 102 is coupled to the frame 11, the second member 114 may be rotated to a deployed position shown in Figure 4 and coupled to the frame 11, optionally at the deflector panel 18 as shown in Figure 4. The pivot joint 13 may also be used to further control movement of the support structure 102 as the crash protection structure 100 collapses during a collision. For example, when arranged as shown in Figure 4 the pivot joint 113 may allow the rear end of the support structure 102 to move down towards the deflector panel 18. It will be appreciated that where the tether 110 comprises a first member 112 and a second member 114 the straight-line distance between the second coupling point 134 and the third coupling point 136 may substantially change.

Where the tether 110 comprises a pivot joint 113, the absolute distance between the second coupling point 134 and the third coupling point 136 may change as the crash protection structure 100 collapses, as the first member 112 rotates relative to the second member 114. However, the tether 110 may be arranged to maintain a substantially constant vertical distance between the second coupling point 134 and the third coupling point 136. The vertical distance may be defined normal to an upper surface of the support structure 102 and/or normal to a surface on which the vehicle 10 is travelling. In this way, the tether 110 may be arranged to permit translation of the support structure 102 in the horizontal direction towards the corresponding engagement surface 123. The distance that is maintained substantially constant by the tether in this case may therefore be a vertical distance.

The pivot joint 13 may comprise a spring 116 and/or a damper 118 as shown in Figure 4. The spring 116 and/or the damper 118 may be used to control the behaviour of the pivot joint 13, for example by increasing the stiffness of the joint. This may be beneficial for resisting movement of the support structure 102 to control the position of the engagement surface 122. It will be understood that the pivot joint 13, spring 116 and damper 118 are optional and that the tether may be a single rigid bar joining the second and third coupling points 134, 136, as shown in Figure 3.

The first member 112 and second member 114 may be arranged to decouple once the engagement surface 122 abuts the corresponding engagement surface 123, or once the support structure is embedded in the frame 11. Beyond this point there may be no requirement to control subsequent movement of the support structure 102. This may allow the support structure 102 and/or other components to subsequently deform, helping to dissipate energy from the system. Arranging the tether 110 to decouple may itself provide a pathway for dissipating energy as the crash protection structure 100 collapses. In some cases, it may be preferable to arrange the tether 110 such that the second member 114 decouples from the third coupling point 136.

Figure 5 shows an example of the support structure 102. The support structure 102 comprises a first portion 102a for coupling to the electric drive unit 200 and a second portion 102b extending from the first portion 102b.

The second portion 102b comprises two members 124 extending from the first portion 102a and coupled together by a transverse member 126. It will be appreciated that the support structure 102 may be manufactured as a unitary body, for example using casting. Providing the second portion as a series of coupled members allows an aperture to be formed in the support structure 102. This may be beneficial in reducing the weight of the support structure 102 and may allow adjacent components to be housed and/or routed through the support structure 102 which may help with packaging of the components around the crash protection structure 100. The engagement surface 122 may be positioned on the second portion 102b, optionally the engagement surface 122 may be a surface on the transverse member 126.

Figure 6 shows a crash protection structure 100 comprising the support structure 102 of Figure 5. The tether 110, optionally the first member 112, may be arranged to pass through the aperture between the two members 124 and the transverse member 126. Upward movement of the rear end of the support structure 102 may be particularly common as the crash protection structure 100 collapses during collisions. It is therefore preferable to provide a tether 110 that extends downward from the support structure 102 towards the third coupling point 136 because the tether 100 may be stronger in tension than in compression. It will however be appreciated that it is not essential to provide a tether 110 that extends downward from the support structure 102.

The support structure 102 comprises an upper surface 133. Where the tether 110 extends downwards from the support structure 102, it may be beneficial to provide a tether 110 which engages with the upper surface 133 of the support structure 102 as shown in Figure 6. Providing a tether 110 which engages the upper surface 133 of the support structure 102 may provide a stronger coupling between the tether 110 and the support structure 102 compared to a tether 110 that does not engage with the top surface 133 of the support structure 102, at least when the rear end of the support structure 102 moves upward during collapse. This is due to the rear end of the support structure 102 exerting a force directly on the tether 110 rather than on, for example, a fastener coupling the tether 110 to a side surface of the support structure 102, which may fail by shearing at a lower force.

As shown in Figure 6, the first member 112 may engage with the upper surface 133 of the support structure 102. The second coupling point 134 may also be positioned on the upper surface 133 of the support structure 102 as shown in Figure 6. Although shown as being coupled with a fastener, it will be appreciated that the tether 110 may be coupled to the support structure 102 at the second coupling point by any suitable means.

In a further embodiment (not shown), the second coupling point 134 is positioned on a side surface of the transverse member 126 and the tether 110 extends to engage the top surface but is not coupled directly to the top surface. This arrangement may for example improve ease of assembly of the structure by improving tooling access to the second coupling point 134.

Also as shown in Figure 6, the pivot between the first and second members 112, 114 is located close to the second coupling point 134. This limits the flexibility of the tether 110 in the downwards direction compared with the arrangement of Figure 4, whereby the ability of the support structure 102 to deflect downwardly (on the less frequent occasions that a collision results in such deflection) is more limited and accordingly the tether is less likely to allow the engagement surfaces 122, 123 to miss one another on rearward movement of the support structure 102. A pivot close to the third coupling point 136, as well as, or instead of, being close to the second coupling 134, would have a similar effect. However, that may not be as convenient an arrangement for other reasons, such as ease of assembly.

It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application.

Claims

CLAIMS1. A crash protection structure for coupling to a vehicle frame, the crash protection structure comprising: a support structure arranged to be coupled to the vehicle frame at a first coupling point, the support structure comprising an engagement surface arranged to abut a corresponding engagement surface of the vehicle frame and being arranged to be coupled to an electric drive unit; and a tether coupled to the support structure at a second coupling point, wherein the tether extends away from the support structure and is arranged to be coupled to the vehicle frame at a third coupling point, wherein the tether is arranged to maintain at least in one direction a substantially constant distance between the second and third coupling points.
2. A crash protection structure according to claim 1, wherein the vehicle frame comprises a bulkhead, the bulkhead comprising the corresponding engagement surface, and wherein the support structure comprises a rear end adjacent the bulkhead, the rear end of the support structure comprising the engagement surface.
3. A crash protection structure according to claim 2, wherein the bulkhead comprises a reinforced portion aligned with the corresponding engagement surface, and wherein the distance between the third coupling point and the reinforced portion is approximately equal to the distance between the third coupling point and the engagement surface.
4. A crash protection structure according to any preceding claim, wherein the engagement surface comprises a substantially planar surface.
5. A crash protection structure according to any preceding claim, wherein the tether comprises a first member arranged to be coupled to the vehicle frame at the third coupling point and a second member coupled to the support structure at the second coupling point, the first member being pivotably coupled to the second member about a pivot joint.
6. A crash protection structure according to claim 5, wherein the first and second members are arranged to decouple when the engagement surface contacts the corresponding engagement surface.
7. A crash protection structure according to any preceding claim, wherein the second coupling point is proximate the engagement surface.
8. A crash protection structure according to any preceding claim, wherein the engagement surface is arranged to be spaced apart from the corresponding engagement surface.
9. A crash protection structure according to any preceding claim, wherein the tether extends downward from the support structure towards the third coupling point.
10. A crash protection structure according to any preceding claim, wherein the support structure comprises an upper surface, and wherein the tether engages the upper surface of the support structure.
11. A crash protection structure according to any preceding claim, wherein the support structure comprises a first portion for coupling to an electric drive unit, and a second portion extending from the first portion, wherein the second coupling point and the engagement surface are on the second portion, and wherein the second portion comprises two members extending from the first portion and coupled together by a transverse member, and wherein the second coupling point is on the transverse member.
12. A crash protection structure according to any preceding claim, further comprising a first mounting bracket, the first mounting bracket comprising: a body connection point for coupling to a body in white of the vehicle; and a support structure mounting point coupled to the support structure.
13. A crash protection structure according to claim 12, further comprising an electric drive unit mounting bracket coupled to the first mounting bracket at the support structure mounting point and an electric drive unit coupled to the electric drive unit mounting bracket.
14. A vehicle comprising: a vehicle frame; and a crash protection structure according to any preceding claim coupled to the vehicle frame.
15. A vehicle according to claim 14, wherein the vehicle frame comprises a deflector panel configured to separate a first internal vehicle volume from a second internal vehicle volume, and wherein the tether is coupled to the deflector panel at the third coupling point.