GB2452752A

GB2452752A - Folding tailgate

Info

Publication number: GB2452752A
Application number: GB0717897A
Authority: GB
Inventors: Tim Butler; Andrew Walker; Simon Hall; Nick Robinson
Original assignee: Nissan Motor Manufacturing UK Ltd
Current assignee: Nissan Motor Manufacturing UK Ltd
Priority date: 2007-09-14
Filing date: 2007-09-14
Publication date: 2009-03-18
Anticipated expiration: 2027-09-14
Also published as: GB2452752B; GB0717897D0

Abstract

A closure assembly such as a tailgate 70 for a vehicle 10 is provided. The closure assembly comprises an upper segment 5 being pivotally connected to the vehicle 10; a lower segment 7 being pivotally connected to the first segment 5; and a mechanism 2 for controlling a two stage process for opening and/or closing the tailgate. The mechanism 2 controls a first stage in which the upper 5 and lower 7 segments move together as a single piece and a second stage in which the lower segment 7 pivots relative to the upper segment 5.

Description

1 2452752

IMPROVEMENTS IN OR RELATING TO VEHICLE CLOSURES

The present invention relates to improving the vehicle closures, in particular closures for the cargo compartment of a motor vehicle. The term closure is used in this specification to refer to doors and tailgates that close apertures within vehicles.

There is an increasing trend in the sales of motor vehicles with cargo or luggage compartments enclosed, at least in part, by a tailgate. Such vehicles, include hatchbacks, SUVs, MPVs, coupes, and light commercial vehides. These are practical vehicles which provide the user with the greatest possible access to the available luggage compartment volume.

There is also a pronounced trend within the motor industry for vehicles increasing in size for any given category. This is particularly true of the sports utility vehicle or SUV, which provides the user with a high driving position, good visibility and large cargo carrying capacity. These attributes are attracting an ever increasing percentage of the new car sales market share.

As these vehicles increase in size so the size of the tailgate increases proportionally and this presents several problems to the user. The first problem is that as the vehicle size increases, the height of the fully open tailgate also increases. This can cause difficulties for users of a smaller stature who find it difficult to reach the tailgate in order to close it.

In order to address this problem some manufacturers have provided the vehicle with power assistance for the tailgate so that the user may open and close the tailgate remotely.

Another issue raised by the trend of increasing vehicle size is that as the tailgate becomes larger so the amount of space required to open it also increases. This can prove awkward for the user who wishes to access the luggage compartment when the vehicle is parked in close proximity to parked cars or other obstacles.

In order to address this issue, some manufacturers have produced vehicles with split tailgates. Such vehicles typically have two doors mounted either to the substantially vertical or horizontal sides of the rear of the vehicle luggage compartment. These doors have to be opened separately which may not be convenient for the user.

Additionally, split tailgates tend to suffer unsightly obstructions across the rear window caused by the door or tailgate frame. Furthermore, split tailgate configurations are also typically less rigid when closed than a single piece tailgate and, as a result, they can suffer from squeaks and rattles which may not be acceptable to the user.

It is in the context of these problems that the present invention has been made.

According to the present invention there is provided a closure assembly for a vehicle, the closure assembly comprising: an upper segment being pivotally connected to the vehicle; a lower segment being pivotally connected to the first section; and a mechanism for controlling a two stage process for opening and/or closing the tailgate, the process comprising a first stage in which the upper and lower segments move together as a single piece and a second stage in which the lower segment pivots relative to the upper segment.

The first stage of the opening process ensures that the lower edge of the lower segment of the closure is clear of the structure of the vehicle so that, as the second stage commences, the lower edge of the lower section of the closure does not make contact with the structure of the vehicle. The first stage also provides the advantage that the latching system and perimeter weather seal may be common to vehicles with a standard closure.

The pivoting of the lower segment relative to the upper segment allows the closure to be opened with a considerable reduction in the step back distance.

The dosure may be a tailgate. The tailgate is typically the largest closure on any given vehicle. The benefits of the folding assembly are therefore most apparent with the large aperture provided in the tailgate of a vehicle.

The mechanism for opening and/or closing the closure may be powered. The provision of a powered mechanism allows the closure to be operated with ease, potentially even remote from the vicinity of the rear of the vehicle.

The closure assembly may further comprise means for decoupling the upper segment from the lower segment. The decoupling means may be a latch which may be part of the pivotal connection between the upper and lower segments of the closure assembly.

The provision of a decoupling means results in additional functionality of the closure assembly in that the closure also be divided into a separate upper and lower segments and the lower segment can be pivoted down to provide a flat surface for picnics and the like.

The upper segment may further comprise a glass portion that is configured to be opened separately from the upper segment. The provision of a glass portion or window that can be opened separately from the opening of the tailgate as a whole provides the user with additional flexibility in accessing the interior of the vehicle.

The upper segment may be pivotally connected to the vehicle along a horizontal axis.

The upper segment is preferably attached to the vehicle along a horizontal axis in the vicinity of the roof of the vehicle. In the case when the closure is a tailgate, attaching the upper segment of the tailgate to an upper edge of the cargo compartment opening, the visual appearance of the tailgate does not differ considerably from a standard tailgate on a SUV or similar vehicle. This is reassuring for the customer who is provided with additional functionality without losing the familiar visual appearance of the vehicle.

Alternatively, the upper segment may be attached to the vehicle along a vertical axis in the vicinity of the side of the vehicle. This alternative case is more appropriate for side doors or the rear door of a delivery vehicle or the like.

The closure assembly may further comprise a proximity sensor that is linked to the opening mechanism to stop to opening of the closure to prevent contact with an obstacle.

The provision of a proximity sensor linked to the opening mechanism prevents the closure from contacting obstacles that may not have been perceived by the user when the opening mechanism was actuated. A further sensor may also be provided that is configured to monitor the point where the upper segment and the lower segment interface. The intention of this sensor is to slow, or even stop the movement of the closure when an obstruction, such as the user's fingers, is identified between the upper segment and the lower segment. Without a sensor configured to monitor this area, it would be possible for the user to catch their fingers or clothing between the upper and lower segments of the closure.

The lower segment may be configured to remain substantially vertical dunng opening.

This is especially appropriate in the case when the closure is a tailgate. The lower segment of the tailgate typically has the mountings for the vehicle registration plate and the tail lights and therefore arranging the tailgate mechanism such that the lower segment remains substantially vertical throughout the opening process ensures that these items are not obscured at any time during the opening of the tailgate. Furthermore, the features remain on view even when the tailgate is fully opened which increases the overall visibility of the vehicle from behind.

The present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows an example of a prior art vehicle tailgate in the fully closed and in an open position representing the maximum step back' distance required when using such a tailgate; Figure 2 shows an example of the present invention, with the tailgate in the fully closed and in an open position representing the maximum step back' distance required when using such a tailgate, Figures 3a and 3b show an example of an opening mechanism for the tailgate of the present invention which is configured to provide the tailgate with a two-stage opening motion; Figures 4a to 4f are a series of schematic images showing the opening of the tailgate of the example of the present invention shown in Figures 2 and 3; Figure 5 shows an example of a tailgate opening mechanism mounting bracket for the present invention; Figures 6a and 6b show a hydraulic actuation system for a powered example of the present invention in the tailgate opening condition and the tailgate dosing condition; and Figures 7a to 7d show a further example of the present invention where the tailgate may be opened either in the manner of the example of the present invention shown in Figures 2, 3 and 5 or, alternatively, can be opened as a split tailgate manner to provide additional functionality for the user.

Figure 1 shows a typical tailgate assembly 1 for a passenger vehicle 10 such as a motor car, SUV, MPV or delivery vehicle. The tailgate is shown in two positions, a fully closed position S and the position 0 representing the point of maximum of rearward excursion.

The distance X1 is the maximum excursion of the tailgate beyond the rear of the vehicle.

This distance is also known as the "step back" distance, because it is the distance the user must typically step back from the position required to reach the tailgate handle, initiating the opening, to the position required to allow the tailgate to open without obstruction. A large step back distance X1 may be problematic for a vehicle that is used in an area where available space around the vehicle is at a premium such as when parked close to a wall, vehicle or other obstruction.

Figure 2 shows an example of the present invention. The tailgate is shown in three positions, namely (a) fully closed, (b) fully open, showing the lower tailgate segment fully folded against the upper tailgate segment and (C) the position of maximum rearward excursion, which results in the maximum step back distance, X2. Comparing the step back distances of Figure 1 and Figure 2, X1 and X2, the reduction in step back' distance required for the same size vehicle tailgate may be clearly seen. The tailgate of the present invention has an upper tailgate segment 5 connected to the vehicle 10 by an upper segment pivot bearing 6 and connected to a lower segment tailgate segment 7 by a lower segment pivot bearing 8. The tailgate assembly 70 of the present invention comprises the upper and lower segments (5 and 7 respectively) and associated pivot bearings (6 and 8 respectively).

Figures 3a and 3b show the tailgate of the present invention in the closed and partly open conditions respectively. Figures 3a and 3b show detail of the opening mechanism which is configured to provide the tailgate with a two-stage folding or opening motion.

The tailgate opening mechanism is shown in Figures 3a and 3b. The mechanism comprises an actuator 4, a link arm 2, an upper tailgate segment 5, an upper tailgate segment pivot 6, a lower tailgate segment 7, a lower tailgate segment pivot 8 and an actuator mounting bracket 3 for attaching the tailgate and associated mechanism to the vehicle 10. Further detail of the bracket 3 is shown in Figure 5.

In total there are four main pivot points in the tailgate opening mechanism, namely the upper segment pivot bearing 6, the lower segment pivot bearing 8, a link arm tailgate pivot bearing 24 and an actuator mounting bracket sliding pivot bearing 38.

The link arm 2 takes the form of a crank with an upper, short crank arm 21 and a lower, long crank arm 23 connected together by a link arm actuator pivot bearing 22. The lower, long crank arm 23 is connected to the lower tailgate segment 7 via a link arm tailgate pivot 24 located at the lowermost end of the lower crank arm. The short, upper crank arm 21 is positioned adjacent to the vehicle roof 11 and is connected to the vehicle via a sliding pivot bearing 38 and a link arm body pivot 20. The link arm body pivot 20 is movable between a first position 40 as shown in Figure 3a and a second position 42 as shown in Figure 3b.

Figure 3a shows the tailgate assembly 70 in the closed position where the link arm body pivot 20 is in the first position in the sliding pivot bearing 38. In order for the tailgate assembly 70 to move from the fully closed position shown in Figure 3a to the position shown in Figure 3b, the actuator 4 must apply a force to the link arm 2.

The link arm body pivot 20 is located in a first position 40 in the sliding pivot bearing 38 when the tailgate is in the closed position. When a force is first applied to the link arm 2 by the actuator 4, the link arm effectively rotates about the upper segment pivot bearing 6 and the link arm body pivot 20 moves from the first position 40 to the second position 42. As the link arm body pivot 20 moves it prescribes a substantially arcuate path about the upper segment pivot bearing 6 guided by the sliding pivot bearing 38.

Once the link arm body pivot 20 has reached the second position 42 it is prevented from executing further translational motion and is forced to rotate, initiating the second stage of the tailgate motion. Figure 3b shows the tailgate during the second stage of opening where the link arm body pivot 20 is in the second position 42 in the sliding pivot bearing 38.

The transition from first stage to second stage opening is called the fold point as it is the point where the lower tailgate segment 7 starts to rotate towards the upper tailgate segment 5. The fold point can be tuned in order to allow a vehicle designer to provide a vehicle with styling features such as body or bumper contours that may otherwise be in danger of making contact with the tailgate during opening or may limit the extent to which the tailgate may be opened.

The fold point can be tuned by one or more of the following: increasing the length of the arcuate path prescribed by the sliding pivot bearing 38 to increase the duration of the first stage of opening motion of the tailgate, where the upper and lower tailgate segments move together about the upper tailgate segment pivot bearing 6; positioning the sliding pivot 38 nearer to the roof 11 of the vehicle; and changing the ratio of the length of the arms 21, 23.

After the fold point the tailgate folds due to the difference in length between the upper tailgate segment 5 and the lower crank arm of the link arm 2 between the actuator and the link arm tailgate pivot 24. The motion of the tailgate opening from fully closed to fully open is shown in Figure 4.

By tuning the relative positions and types of the main pivot points, the following tailgate opening characteristics may be tuned to suit the needs of a particular vehicle: the maximum height of the tailgate above the ground which may need to be limited by the maximum reach of the user and the available clearance when the tailgate is operated within a building such as a garage or other parking structure; the tailgate fold ratio which is the difference in angle between the upper and lower segments when the tailgate is in the fully closed position versus the fully open position; the fold rate which is the time taken for the tailgate to cycle from the fully closed position to the fully open position. This is controlled partly by the force applied by the actuator and partly by the proportion of the upper segment opening angle in which the lower segment is rotated towards the upper segment.

The maximum height of the tailgate above the ground can be altered depending on the angle between the upper and lower segments when the tailgate is fully open and depending on the angle of the upper segment relative to the substantially horizontal roof of the vehicle. For example if the overall height of the vehicle is not a limiting factor then the upper segment may protrude above the roof when the tailgate is fully opened and the angle between the upper and lower segments can be relatively large, e.g. 60 so that the light clusters and registration plate are still visible.

Conversely, if the overall maximum height of the vehicle when the tailgate is fully opened is a limiting factor then the upper segment may be tuned so that it extends substantially parallel to the roof when the tailgate is fully open. In order to ensure that the head room available for the user is maximised in this case, the angle between the upper and lower segments is minimised.

Figures 4a to 4f show the tailgate of the present invention in a number of positions from the fully closed position in Figure 4a to the fully open position shown in Figure 4f. Figure 4a shows the actuator mounting bracket 3 as a dotted line to show the relative position of this bracket with the actuator 4, link arm 2 and the tailgate assembly 70. The actuator mounting bracket 3 is not shown in Figures 4b to 4f for clarity. Figure 4b shows the extent of opening of the tailgate assembly 70 at the end of the first stage of opening where the upper and lower tailgate segments open as one. Figure 4c shows the tailgate assembly 70 at the tailgate fold point. Figures 4d and 4e show the tailgate as it continues to move in the second stage towards a fully open position which is shown in Figure 4f. It may be seen from Figures 4a and 4b that the link arm body pivot 20 is shown in black to signify that it occupies the first position 40 of the sliding pivot 38. The link arm body pivot 20 shown in Figures 4c to 4f is shown in white to signify that is occupies the second position 42 of the sliding pivot 38.

Figure 5 shows a detailed view of the actuator mounting bracket 3. The tailgate is connected to the vehicle body by means of two actuator mounting brackets 3 positioned at either side of the vehicle roof 11 at the luggage compartment aperture.

The actuator mounting bracket 3 provides an actuator mounting pivot bearing 35 for connecting the actuator 4 to the vehicle 10. In addition, the actuator mounting bracket 3 provides an actuator mounting bracket sliding pivot for attaching the link arm 2 to the vehicle 10, and an upper tailgate segment pivot bearing 6 for mounting the upper tailgate segment 5 to the vehicle 10. The sliding pivot 38 permits a pre- determined amount of motion between the link arm pivot 20 and the actuator mounting bracket 3.

The actuator mounting bracket 3 of Figure 5 has an elongate rigid structure or main body made from a suitably resilient material such at a metal or plastics material. The actuator mounting bracket 3 is attached to the vehicle at suitably reinforced locations on the vehicle body (not shown) so as to be able to transmit the forces required to open the tailgate without excessive deformation of the vehicle body.

The actuator mounting bracket 3 has two body attachment points 36 situated along the upper side of the actuator mounting bracket main body 30. These body attachment points 36 may provide a suitable feature to allow the actuator mounting bracket to be bolted, clipped, riveted, bonded, welded or secured to the vehicle body by some other suitably robust means.

The actuator mounting bracket 3 is provided with a first projection 32 and a second projection 34 from the main body 30 of the actuator mounting bracket 3. The first or rear projection 32 extends from the upper rear edge of the actuator mounting bracket main body 30. This projection provides the upper segment pivot point 6 by means of a through hole through the rear projection 32. It will be appreciated that the same effect may be achieved by splitting the functions performed by this actuator mounting bracket 3 into several brackets or body reinforcement panels without affecting the performance or functionality of the present invention.

The second or front projection 34 of the actuator mounting bracket 3 projects from the front lower edge of the actuator mounting bracket main body 30. The second projection 34 provides the actuator mounting pivot bearing 35 for the actuator (not shown). This provides a suitably rigid connection for the actuator to the vehicle body. The actuator attachment point 35 is provided by a through hole which allows the actuator to rotate as required relative to the vehicle body during the tailgate opening or closing cycle. The through holes of both the first arid second projection may be provided as a plain hole with the bearing portion provided by a corresponding securing pin or may alternatively be provided with a pressed insert that provides a suitably robust, low friction bearing surface.

The example of the actuator mounting bracket 3 shown in Figure 5 has a series of substantially triangular weight reduction cut-outs 31 through the main body 30 of the actuator mounting bracket 3. It will be appreciated that these mass reduction features represent just one of many potential solutions to minimise component mass which may not be appropriate depending on the material and shape of the actuator mounting bracket used.

The actuator mounting bracket 3 is provided with one further through hole towards the rear end of the main body of the actuator mounting bracket 3. This through hole takes the form of an arcuate slot and provides the link arm 2 with a sliding pivot 38.

Although, in the example shown in the Figures, the arcuate path is provided by a sliding pivot 38, the arcuate path could alternatively be provided between the upper segment pivot point 6 and an end stop.

Figures 6a and 6b show schematic diagrams of a hydraulic actuator system 50 for opening (Figure 6a) and closing (Figure 6b) the tailgate of the present invention. The hydraulic actuator system 50 comprises an oil reservoir 58, an actuator inlet control valve 60, an actuator outlet control valve 62, a reversible hydraulic pump 56 and a hydraulic actuator which, in the example shown, takes the form of a hydraulic cylinder 52 accommodating a hydraulic piston 54 with a first 59 and second 61 oil volume, positioned at either end of the piston 54. Figure 6a shows the configuration of the hydraulic actuator required to open the tailgate of the present invention based on the example shown in Figures 2 to 5. In this case the hydraulic actuator must be extended and the flow of hydraulic oil is shown by the block arrow Fo.

As illustrated in Figure 6a, hydraulic oil is drawn from the oil reservoir 58 by the pump 56 and pumped towards the hydraulic cylinder 52 via control valve 60. The configuration of control valve 60 is selected to allow a communication of hydraulic oil from the pump 56 to the hydraulic cylinder 52 without allowing the hydraulic oil to flow directly back into the oil reservoir 58. For clarity, the cylinder 52 is shown with a first oil volume 59 to the right of the piston 44. This first oil volume 59 is pressurised in order to extend the piston 54 from the cylinder 52. There is a second oil volume 61 to the left of the piston 54. This second oil volume 611s pressurised to retract the piston 54 back into the cylinder 52. To open the tailgate of the present invention the oil in the first oil volume 59 is pressurised by means of the pump 56, while the position of the second control valve 62 is selected to allow oil from the second volume 61 to escape the cylinder 52 and return to the oil reservoir 58.

Figure 6b shows the configuration of the hydraulic actuator required to close the tailgate of the present invention based on the example shown in Figures 2 to 5. The direction of hydraulic oil required to close the tailgate is shown by the block arrow Fc. In the case of Figure 6b, the hydraulic oil is pumped from the reservoir 58 by pump 56 to the second oil volume 61 of the hydraulic cylinder 52 via control valve 62. In this condition, control valve 62 is configured to permit a communication of hydraulic oil from pump 56 to hydraulic cylinder 52 without returning directly to the oil reservoir 58. In order for the piston 54 to move to the right as viewed from Figure 6, the control valve 60 must be selectively configured to allow for the communication of hydraulic oil from the first oil volume 59 to the oil reservoir 58. The use of a hydraulic actuator system provides the benefit of being easily packaged whilst being robust and reliable.

The hydraulic circuit shown in Figures 6a and Figure 6b can be augmented with suitable one-way flow valves and directional control valves in order to provide the user with positive control of the system based on the principle of hydraulic lock.

It will be appreciated that the operation of the tailgate of the present invention may be assisted by a variety of means such as pneumatics, springs, motors or counter balance weights.

By changing the relative lengths of the links and the positions of the pivot points and actuator, a folding tailgate may be produced that requires the length of the actuator to decrease rather than to increase in order to open the tailgate. The hydraulic cylinder 52 guides the motion of a hydraulic piston 54 which may be extended from or withdrawn into the cylinder 52 by varying the oil pressure on either side of the piston.

An additional benefit of using a hydraulic based system is that by selectively configuring the position of control valves 60 and 62 the user may be provided with a hydraulic lock feature configured to lock the tailgate in any position desired by the user from fully closed to fully open. This may be achieved by selectively configuring the control valves and 62 to prevent hydraulic oil from flowing into or out of the hydraulic cylinder once the tailgate is in the desired position. The locking of the tailgate also provides an additional safety feature as it can be used as a "fail-safe" mechanism to prevent the unexpected lowering of the tailgate in the case of a failure of the system.

The functionality of the tailgate of the present invention may be further enhanced by the addition of tailgate position sensors and proximity detectors. Such features may be implemented to detect to presence of a person or other obstruction standing in the path of the opening or closing tailgate and take necessary actions to intervene in the control of the motion of the tailgate to prevent an unwanted contact which may otherwise lead to injury or damage. A sensor is also provided in the vicinity of the join between the upper segment and the lower segment. This sensor is intended to monitor the interface between the upper and lower segment and slow or even stop the closing of the tailgate if an obstruction is identified between the upper and lower segments. For example, this sensor would be able to detect the presence of the user's fingers or clothing in the space between the upper and lower segments. The sensor can additionally be provided with an audible or visual alert so that the user is made aware that there is an obstruction.

Figures 7a to 7d show an alternative example of the present invention in which the tailgate assembly, in addition to operating as set out above with reference to Figures 2, 3 and 5, can be selectively opened in a two-stage folding-or split-tailgate mode. In the split-tailgate mode the connection between the upper and lower tailgate segments is unlatched allowing the upper tailgate segment 5 to pivot upwards about the upper segment pivot bearing 6 while the lower segment 7 pivots downwards about a latch mechanism 16 to form a substantially horizontal platform as shown in Figure 7d.

Positioning the lower tailgate segment in a substantially horizontal position may be used to extend the cargo compartment area or to provide a seating area to allow the user to sit substantially outside the vehicle when parked if so desired.

Figure 7a shows the main components of the tailgate system are substantially the same as those in the first example with the addition of a tailgate latch 16, a link arm connector latch 72 and an upper segment link arm guide 76. In addition there must also be provided some means for the user to selectively control the tailgate opening mode such as a switch or handle (not shown) located in a convenient position on the tailgate and / or on a remote control feature of the key.

In this example the lower segment pivot bearing 8 releasably connects the lower tailgate segment 7 to the upper tailgate segment 5 by means of a sliding hinge pin (not shown) that may be controlled by means of a spring loaded latch, a hydraulic or pneumatic actuator or an electromagnet (not shown). This hinge pin (not shown) is in a first position to permit the tailgate to open in a folding-tailgate mode. When the hinge pin is in the first position, it is engaged between the upper and lower tailgate segments, holding them together and allowing the two tailgate segments to hingeably pivot about the lower segment pivot bearing 8 during the tailgate opening and closing cyde.

When the user desires the tailgate to open in the split-tailgate mode the hinge pin of the lower segment pivot bearing 8 is moved to a second position that disconnects the lower tailgate segment 7 from the upper tailgate segment 5. This stage is shown in Figure 7b.

The upper tailgate segment 5 is biased to tend to hold the upper segment 5 in the closed position. It will be appreciated that such biasing tends to mitigate unwanted rattles and leaks when in the closed position and prevent the upper segment moving independently from the motion of the link arm 2. The link arm 2 of this example is provided with a link arm striker piece 78 that co-operates with the link arm connector latch 72 in normal use.

When the assembly is operating in the split-tailgate opening mode, the link arm striker piece 78 presents a low friction surface which may reliably slide out of the link arm connector latch 72 and allow the link arm to move upwards along the upper segment link arm guide 76 to apply an opening force to the upper segment 5 alone. The process of the link arm striker piece 78 engaging with and moving upwards along the upper segment link arm guide 76 is shown in Figure 7c.

The lower tailgate segment 7 may also be provided with a biasing force that either holds the lower tailgate segment in the closed position or in a slightly open orientation, i.e., with the top edge of the lower tailgate segment slightly further away from the vehicle body than to lower edge of the lower segment, as shown in Figures 7b and 7c. In this way a light biasing force tends to mitigate rattles of the tailgate assembly when the vehicle is in motion. Presenting the lower tailgate segment in a slightly open orientation presents the top edge of the lower tailgate segment in an orientation that is ergonomically optimised to allow the user to grip and lower the lower tailgate segment to a substantially horizontal position.

The tailgate system may be further provided with powered assistance to open and close the lower tailgate segment when operating in the split-tailgate mode. The source of the lower tailgate segment assistance could be packaged in the vehicle body or the tailgate segment, and may take the form of a motor, spring, or other suitable means. The level of assistance may be sufficient to open and close the lower tailgate segment without requiring additional manual force from the user. Alternatively, the level of assistance provided is purely a counter force to compensate for the moment required to return the lower tailgate segment to a substantially vertical orientation. Once the lower tailgate segment has been returned to a substantially upright orientation it may be reconnected with the upper tailgate segment via the lower tailgate pivot bearing and hinge pin arrangement.

It will be appreciated that additional latches may be provided to latch or lock both tailgate segments to the vehicle body when so desired to provide additional security over the hydraulic lock function provided by the hydraulic actuator system.

Claims

1. A closure assembly for a vehicle, the closure assembly comprising: an upper segment being pivotaDy connected to the vehicle; a lower segment being pivotally connected to the first section; and a mechanism for controlling a two stage process for opening and/or closing the tailgate, the process comprising a first stage in which the upper and lower segments move together as a single piece and a second stage in which the lower segment pivots relative to the upper segment.

2. The closure assembly according to claim 1, wherein the closure is a tailgate.

3. The closure assembly according to claim I or claim 2, wherein the mechanism for opening and/or closing the closure is powered.

4. The closure assembly according to any one of the preceding claims, further comprising means for decoupling the upper segment from the lower segment.

5. The closure assembly according to any one of the preceding claims, wherein the upper segment further comprises a glass portion that is configured to be opened separately from the upper segment.

6. The closure assembly according to any one of the preceding claims, wherein the upper segment is pivotally connected to the vehicle along a horizontal axis.

7. The closure assembly according to any one of the preceding claims, wherein the upper segment is pivotally connected to the vehicle along a vertical axis.

8. The closure assembly according to any one of the preceding claims, further comprising a proximity sensor that is linked to the opening mechanism to stop to opening of the closure to prevent contact with an obstacle.

9. The closure assembly according to any one of the preceding claims, wherein the lower segment remains substantially vertical during opening.

10. A closure member substantially as herein described with reference to the accompanying drawings.