GB2546780A - Loading system - Google Patents

Abstract

A pivotable loading system for a vehicle, such a recovery vehicle or tow truck. The loading system comprises a loading frame 100, which may pivot with respect to a base unit 18 about a hinge 20. The loading frame is made up of two parts, a tipping sub-frame 110, and a platform 120, onto which a vehicle may be loaded. The sub-frame 110 and platform 120 are connected to one another by a pivotable platform coupling 170. The sub-frame 110 and platform 120 are each connected to respective first and second actuators, 130, 140, which meet at the at a pivotable actuator coupling 150, connecting the two actuators. These actuators may be used to slide the platform 120 along the tipping subframe until the pivotable platform coupling 170 is aligned with the pivotable actuator coupling 150, then moving two pivotable couplings 170, 150 together towards the tail end of the tipping sub-frame 110. The actuators may comprise hydraulic cylinders.

Description

LOADING SYSTEM

The present disclosure relates to a loading system.

In particular the disclosure is concerned with a loading system for a vehicle. Background

Loading systems for vehicles are well known in the art. For example, a recovery vehicle (or ‘tow truck’) may have a loading system to load another vehicle (e.g. a car) for delivery to a customer, or to be transported to a garage if it requires maintenance.

One such loading system involves a slide-back body which may be extended from the rear section of a truck to create a ramp for the car to be loaded onto.

In known examples, the slide-back body is moved relative to the rest of the truck by use of an actuator system using chains or rack and pinion arrangements. However, both are prone to high wear rates because of their exposure to weather and debris. Chains require regular adjustment, and chains, along with rack and pinion arrangements, are inherently difficult, and hence inconvenient and/or costly, to maintain.

Additionally, where chain and rack and pinion arrangements are employed, a drive unit is required for each, which significantly increases the weight of the vehicle, and thereby reduces the maximum payload of the vehicle.

Another problem with conventional arrangements is that the angle the ramp makes with the ground is too steep for some car configurations. For example, front end spoilers on performance cars may extend so close to the ground that the car may not be able to travel up the ramp without damaging the spoiler, thereby incurring costs and reputational damage for the carrier, and further inconvenience and annoyance for the vehicle owner.

Hence a loading system which overcomes the demerits of known systems is highly desirable.

Summary

According to the present disclosure there is provided an apparatus and method as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

Accordingly there may be provided a loading system for a vehicle, comprising: a base unit; a loading frame carried by the base unit and pivotable relative to the base unit about a hinge, the loading frame comprising: a tipping sub-frame and a platform pivotably connected to one another by a pivotable platform coupling, a first actuator fixed to the tipping sub-frame, a second actuator fixed to the platform, and the first actuator and the second actuator are pivotably connected to each other by a pivotable actuator coupling; the actuators being operable to move the platform relative to the tipping sub-frame between a stowed configuration in which the platform is located on and supported along at least some of its length by the tipping sub-frame; and an extended configuration, in which the platform has been moved along the tipping sub-frame away from the stowed configuration, and is supported from the tipping sub-frame at least by the pivotable platform coupling.

The platform may be pivotable relative to the tipping sub-frame about the pivotable platform coupling when the pivotable platform coupling and the pivotable actuator coupling are aligned.

The tipping sub-frame may comprise a support rail which extends at least part of the length of the tipping sub-frame, wherein the platform is carried by the rail; and moveable relative to and along the rail.

The pivotable platform coupling may comprise a saddle, the saddle being mounted on, and movable along, the tipping sub-frame rail, and pivotably coupled to the platform.

The tipping sub-frame may comprise a guide track which extends at least part of the length of the tipping sub-frame, and the actuator coupling is located in the guide track such that the first actuator is operable to move the actuator coupling along the guide track.

The guide track may extend from a tail end of the tipping sub-frame to a location substantially halfway between the head end and tail end of the tipping sub-frame.

The loading system may further comprise: a third actuator which is : pivotably coupled to the base unit, pivotably coupled to the tipping sub-frame of the base unit, and operable to pivot the loading frame relative to the base unit to thereby pivot the loading frame is about its hinge, and pivot the tipping sub-frame and platform relative to each other about the pivotable platform coupling.

The loading system may further comprise: a control system configured to: perform a sequence of operations to change the loading frame from the stowed configuration to the extended configuration, and perform another sequence of operations to change the loading frame from the extended configuration to a stowed configuration.

All of the actuators may share a common drive unit.

At least one of the actuators may be an hydraulic cylinder.

All of the actuators may be hydraulic cylinders.

The drive unit may comprise a source of pressurised hydraulic fluid; all of the hydraulic cylinders being in fluid communication with the source of pressurised fluid such that the drive unit is operable to supply all of the hydraulic cylinders during their operation.

There may also be provided a method of operating a loading system for a vehicle according to the present disclosure comprising the steps of : operating the second actuator to move the platform along the tipping sub-frame until the pivotable platform coupling and the pivotable actuator coupling are aligned; operating the first actuator to move the platform further along the tipping sub-frame such that the pivotable actuator coupling and pivotable platform coupling are moved together towards the tail end of the tipping sub-frame.

The method may further comprise the step of pivoting the tipping sub-frame relative to the base unit, and pivoting the platform relative to the tipping sub-frame.

There may also be provided a vehicle comprising a loading system of the present disclosure operable by the method of the present disclosure.

Thus there is provided a loading system for a vehicle which achieves a low approach angle so that vehicles with a low ground clearance may be loaded without risk of damage. Additionally, the configuration of the loading system vehicle is such that overall it may be lighter than a loading system of the related art, thereby increasing the potential payload of any vehicle to which it is attached.

Brief Description of the Drawings

Examples of the present disclosure will now be described with reference to the accompanying drawings, in which:

Figure 1 is a side view of a vehicle with a loading system according to the present disclosure in a stowed configuration;

Figure 2 is a plan view of the vehicle shown in Figure 1;

Figure 3 is a perspective view of the vehicle of Figures 1, 2 with the loading system in an extended configuration;

Figure 4 is a perspective view of a pivotable platform coupling and pivotable actuator coupling of the loading system;

Figure 5 is an enlarged view of the pivotable actuator coupling shown in Figure 4;

Figure 6 shows a view of the pivotable platform coupling shown in Figure 4;

Figure 7 shows a sectional view of the pivotable platform coupling and pivotable actuator coupling shown in Figures 4 to 6;

Figures 8, 9 show a side view and plan view respectively of the loading system when partially extended compared to that shown in Figures 1,2;

Figures 10, 11 show a side view and plan view respectively the loading system when further extended compared to the view of Figures 8, 9;

Figures 12, 13 show a side view and plan view respectively of the loading system when further extended compared to the view of Figures 10, 11; and

Figures 14, 15 show a side view and plan view respectively of the loading system when fully extended.

Detailed Description

Figures 1 and 2 show a side and plan view respectively of an example vehicle 10 which is fitted with a loading system 12 according to the present disclosure.

In this example, the vehicle 10 is a “tow truck” type vehicle, such as a light commercial vehicle or a large goods vehicle. The vehicle is suitable for transportation of loads / cargo which are loaded onto a back of the truck 10 using the loading system 12. In particular it is intended for the loading, carriage and delivery of other vehicles, such as cars.

In the example shown the vehicle 10 is a flatbed lorry (or ‘truck’) having a chassis frame 14 (or “chassis”) extending away from a cab 16, and thus extending to the “rear” or “tail” of the vehicle 10, upon which the loading system 12 of the present disclosure is provided. In use, the truck 10 sits on a base surface 17 (e.g. the ground, road or other base upon which the system may be operated on). By way of example the base surface 17 is shown to be flat and level, but in practice this may not be the case. However, the angle or nature of the base surface 17 is not relevant to the structure and operation of the device of the present disclosure.

In Figures 1 and 2 the loading system 12 is shown in a stowed configuration. The stowed configuration is an “in transit” state in which the loading system 12 has been retracted to sit on the chassis of the truck, with or without any cargo. Figure 3 shows a perspective view of the vehicle where the loading system 12 is provided in an extended configuration. The extended configuration defines the state of the loading system 12 when it has formed a ramp for loading cargo onto the back of the truck.

The loading system 12 comprises a base unit 18. The base unit 18 may comprise at least part of the chassis 14 of the vehicle 10. The base unit 18 carries a loading frame 100, which may also be referred to as a “chassis sub-frame”. In the example shown the base unit 18 and the loading frame 100 have a generally rectangular shape to fit onto a rear portion of the vehicle 10. That is to say, the chassis 18 and chassis sub-frame 100 each have length and width, the length being larger than the width. In this example, the chassis sub-frame 100 is longer than the chassis 18 such that the chassis sub-frame 100 extends past a rear (i.e. “tail”) end of the chassis 18 when in the stowed configuration.

As shown clearly in Figures 1, 3, the loading frame 100 is carried by the base unit 18 and pivotable relative to the base unit 18 about a hinge joint 20. That is to say, the loading frame 100 is mounted such that it is pivotable relative to the base unit 18 about a first pivot (or “pivot axis’) defined by the hinge 20.

The loading frame 100 comprises a tipping sub-frame 110 (or “first sub-frame’) and a platform 120 (or “second sub-frame’) connected to one another by a pivotable platform coupling 170. In the example shown the tipping sub-frame 110 and the platform 120 have a generally rectangular shape, with each sub-frame 110, 120 having a length which is greater than its width. The tipping sub-frame 110 and platform 120 may be of different lengths. In the example shown the lengths of the tipping sub-frame 110 and platform 120 are substantially equal.

The tipping sub-frame 110 and the platform 120 are movable relative to each other such that, in use, the platform 120 may be drawn along the tipping sub-frame 110 to either extend or contract the loading frame 100.

Although not shown in the figures, a plate or sheet of material may located on and supported by the platform 120, where the cargo is drawn onto and locked into position on the top of the plate/sheet of material. A first actuator 130 extends along a lengthwise direction, or longitudinal direction, of the tipping sub-frame 110. The first actuator 130 is fixed to the tipping sub-frame 110. The first actuator 130 may be coupled at one of its ends to a head end 112 (i.e. the nominal “front” end) of the tipping sub-frame 110 and extend towards a tail end 114 (i.e. the nominal “rear’) of the tipping sub-frame 110. In this example, the first actuator 130 is parallel to a longitudinal edge of the tipping sub-frame 110 and extends along the centre of the tipping sub-frame 110. That is to say, it is approximately equally spaced between both longitudinal edges of the tipping sub-frame 110. In other examples, the first actuator 130 may be closer to one longitudinal edge of the tipping sub-frame 130. One or more actuators arranged and acting in parallel may be provided as an alternative to a single first actuator 130. A second actuator 140 is fixed to the platform 120. The second actuator 140 may be coupled at one of its ends to a tail end 124 (i.e. the nominal “rear” end) of the platform 120 and is arranged to extend towards a head end 122 (i.e. the nominal “front” end) of the platform 120. The second actuator 140 extends along a lengthwise direction of the platform 120 and is aligned with the first actuator 130.

As shown in Figures 4, 5, 7 the first actuator 130 and the second actuator 140 are connected to each other at their other ends by a pivotable actuator coupling 150 to define a second pivot (or “pivot axis’) 22. That is to say, in this example the pair of actuators 130, 140 are arranged to extend from the head end 112 of the tipping sub-frame 110 to the tail end 124 of the platform 120 via a pivotable coupling 150.

The actuators 130, 140 are operable to move the platform 120 relative to the tipping sub-frame 110, between the stowed configuration and the extended configuration. Thus in the stowed configuration the tail end 124 of the platform 120 is a first distance from the head end 112 of the tipping sub-frame 110. In the stowed configuration the platform 120 is located on and supported along at least some of its length by the tipping sub-frame 110, as shown in Figures 1,2.

In the extended configuration the tail end 124 of the platform 120 is a second distance from the head end 112 of the tipping sub-frame 110, the second distance being substantially greater than the first distance. In the extended configuration, the platform 120 has been moved along the tipping sub-frame 110 away from the stowed configuration, and is supported from the tipping sub-frame 110 at least by the pivotable platform coupling 170, for example as shown in Figures 14,15.

The tipping sub-frame 110 comprises a rail 111 arranged to carry the platform 120, and relative to which the platform 120 is movable. That is to say, the platform 120 is carried by the rail 111, and moveable relative to and along the rail 111. Put another way, the loading frame 100 is configured such that the platform 120 is carried by the rail 111 and translatable relative to the tipping sub-frame 110 along the rail 111. In this example, the rail 111 extends from the head end 112 of the tipping sub-frame 110 to a tail end 114 of the tipping sub-frame 110. In other examples, the rail 111 extends at least part of the length of the tipping sub-frame 110. The rail 111 may have a generally rectangular hollow cross-section.

Additionally, the platform 120 may comprise rails 121 made from angle iron or-the-like (for example have an inverted “L” shaped cross-section), so that a side of the platform rails 121 may be located adjacent the tipping frame rails 111, but are free to slide and lift away from the tipping frame rails 111 when the platform 120 is pivoted relative to the tipping sub-frame 110.

In the example shown, the tipping sub-frame 110 comprises a pair of rails 111. A first rail 111 is located at a first longitudinal edge of the tipping sub-frame 110, and a second rail 11 is located at a second longitudinal edge of the tipping sub-frame 110.

In other examples, the tipping sub-frame 110 may comprise a single rail 111, for example located centrally, or three or more rails 111, for example arranged parallel with each other to share load.

The platform 120 is retained by a guide sleeve (or “saddle’) 160 of the loading frame 100, an enlarged view of which is shown in Figures 4, 6. The saddle 160 is mounted onto the rail 111 and movable along the tipping sub-frame rail 111 of the tipping sub-frame 110. Additionally the saddle 160 is pivotably coupled to the platform 120 by a hinge arrangement provided as a pivotable sub-frame coupling 170. Hence the platform 120 is pivotable relative to the tipping sub-frame 110 via the pivotable sub-frame coupling 170.

The saddle 160 forms a channel so that it may be located on the rail 111. Hence, the saddle 160 may remain engaged with the rail 111 as the sleeve 160 is moved (i.e. translated) along the rail 111. In some examples, the saddle 160 may completely surround the rail 111. In other examples the saddle 160 may be arranged to fit part way, but not the whole way, around the rail 111.

Thus the saddle 160 and the pivotable sub-frame coupling 170 are movable with the platform 120 relative to the tipping sub-frame 110. That is to say, the platform 120, comprising the saddle 160 and pivotable sub-frame coupling 170, may be translated along the tipping sub-frame 110.

As shown in Figures 4, 5, 7 the tipping sub-frame 110 comprises a guide track 118 which extends at least part of the length of the tipping sub-frame 110. The pivotable actuator coupling 150 is located in the guide track 118 and movable along the guide track 118. As shown in Figures 4, 5, 7 the pivotable actuator coupling 150 may comprise a pair of rollers 152 which engage with the track 118 facilitating easy travel of the coupling along the path defined by the track 118. In alternative examples, the pivotable actuator coupling 150 may engage directly with the track 118, or be provided with slide members which slideably engage with the track 118.

In the example shown, the guide track 118 extends from a location substantially halfway between the head end 112 and the tail end 114 of the tipping sub-frame 110 to the tail end 114 of the tipping sub-frame 110.

The loading system 12 comprises a third actuator (i.e. a “tipping” actuator) 180. The third actuator 180 is pivotably coupled to the base unit 18, pivotably coupled to the tipping sub-frame 110 of the base unit 18, and operable to pivot the loading frame 100 relative to the base unit 18 to thereby pivot the loading frame 100 about the hinge 20. In this way, the second pivot axis 22, defined by the coupling 150 between actuators 130, 140 and the coupling 170 between the sub-frames 110, 20, may be rotated about the first pivot axis (i.e. hinge) 20. Further, the tipping actuator 180 provides a means for the tipping sub-frame 110 and platform 120 to be pivoted relative to each other about the pivotable platform coupling 170.

In this example, the loading system 12 comprises a pair of tipping actuators 180 on either side of the base unit 18. In alternative examples, the loading system 12 comprises a single tipping actuator 180, or three of more tipping actuators 180.

All of the actuators may share a common drive unit. That is to say, all of the actuators may be powered by the same prime mover.

One or more of the actuators may comprise a fluid pump, or pumps, in combination with hydraulic cylinders (i.e. “hydraulics”). The actuator drive unit may comprises a source of pressurised hydraulic fluid, wherein all of the hydraulic cylinders are in fluid communication with the source of pressurised fluid such that the drive unit is operable to supply all of the hydraulic cylinders during their operation.

Alternatively one of more of the actuators may comprise a combination of screw rods and screw nuts, rotatable by one or more motors, for example electric motors.

The loading system 12 may further comprise a control system (for example comprising a control unit, or control switched operable by a user) configured to perform a sequence of operations to change the loading frame from the stowed configuration to the extended configuration, and perform another sequence of operations to change the loading frame from the extended configuration to the stowed configuration.

In operation, to change from the stowed configuration (as shown in Figures 1, 2) to the fully extended configuration (shown in Figures 14,15), the second actuator 140 is first operated to move the platform 120 along the tipping sub-frame 110 until the pivotable platform coupling 170 and the pivotable actuator coupling 150 are aligned, as shown in Figures 4, 8 and 9. That is to say, the stroke of the second actuator 140 is such that is may be extended in this step until the pivotable sub-frame coupling 170 is aligned with the actuator pivotable coupling 150 along the second pivot axis 22.

The platform 120 is pivotable relative to the tipping sub-frame 110 about the pivotable platform coupling 170 when the pivotable platform coupling 170 and the pivotable actuator coupling 150 are aligned.

The second actuator 140 is operated first to increase the distance between the head end 112 of the tipping sub-frame 110 and the tail end 124 of the platform 120, as shown in Figures 8, 9. During this operation, the saddle 160 moves along the rails 111, and the pivotable actuator coupling 150 remains in a fixed position in the guide track 180.

As shown in Figures 10,11, the tipping sub-frame 110 is then pivoted with the platform 120 relative to the loading frame 100 by the third actuator 180. This brings the tail end 124 of the platform 120 closer to, or into contact with, the support surface 17 (e.g. the ground).

The first actuator 130 is then operated to further increase the distance between the head end 112 of the tipping sub-frame 110 and the tail end 124 of the platform 120. During this operation, the saddle 160 moves along the rails 111, and the pivotable actuator coupling 150 moves along the guide track 180. That is to say, the first actuator 130 is operated to move the platform 120 further along the tipping sub-frame 110 such that the pivotable actuator coupling 150 and pivotable platform coupling 170 are moved together towards the tail end 124 of the tipping sub-frame 110.

The tipping actuator 180 may be configured such that, during this stage, it may “float” backwards and forward, that is to say it may adjust in length, in response to the movement of the tipping sub-frame 110 and platform 120.

Thus the pivotable sub-frame coupling 170 is first moved towards the tail end 114 of the tipping sub-frame 110 (as shown in the journey illustrated by Figures 1,2 and Figure 4,5) and then the pivotable sub-frame coupling 170 and actuator pivotable coupling 150 are moved at the same time, in the same direction and at the same rate, beyond the tail end 114 of the tipping sub-frame 110 (as shown in the journey illustrated by Figures 8,9; 10,11; and 12,13).

As shown in Figures 12, 13, when the tail end 124 of the platform 120 makes contact with the support surface 17, the platform 120 is pivoted relative to the tipping sub-frame 110 about the second pivot axis 22 defined by the pivotable sub-frame coupling 170 and actuator pivotable coupling 150. As shown in Figures 14, 15, as the first actuator 130 further extends the platform 120 along the tipping sub-frame 110, the platform 120 is further pivoted relative to the tipping sub-frame 110 about the second pivot axis 22. The pivotable sub-frame coupling 170 and actuator pivotable coupling 150 are thus moved below the tail end 114 of the tipping sub-frame 110 towards the support surface 17 (e.g. the ground). This reduces the angle between the platform 120 and the support surface 17, thereby making it easier for a cargo (e.g. a car) to be loaded onto the platform 120, or any platform mounted on the platform 120 for receiving the cargo. This is known as the loading angle. In this example, the loading angle may be between 0° and 4° (degrees).

To change from the extended configuration (Figures 14, 15) to the stowed configuration (Figures 1,2), the above steps are carried out in reverse. That is to say, the first actuator 130 is operated to draw the platform 120 onto the tipping sub-frame 110 (Figures 12, 13 and then Figures 10, 11), the third actuator 180 lowers to bring the tipping sub-frame 110 back to rest on the base unit 18 (Figures 8, 9), and then the second actuator 140 operates to draw the platform 120 further onto the tipping sub-frame 110 along rails 111 until it is in the stowed position (Figures 1, 2).

Although the loading system 12 is shown on the chassis 14 of a road truck, in other examples it may be provided on a trailer attached to a tractor unit to form an articulated lorry. Alternatively, the loading system 12 may instead form part of a rail vehicle, for example a carriage for transporting loads on a rail network. Alternatively it may be provided as part of a ship or air vehicle for the loading, transportation and delivery of cargo loads.

Although in this example, the loading system 12 is provided on the rear portion of a vehicle 10 and configured such that the loading frame 100 is extendable past the tail end of the chassis 14, in other examples the loading system 12 may be configured to extend the loading frame 100 in other directions - for example forwards (where the cab 16 may be at the rear of the vehicle 10) or sideways (e.g. such that it extends from the long edge of the chassis 14). That is to say, the arrangement of the loading system 12 of the present disclosure is not limited to the application shown in the figures and herein described.

Thus there is provided a loading system for a vehicle which achieves a low approach angle so that vehicles with a low ground clearance may be loaded without risk of damage from the system. The small loading angle is advantageous, for example, so that a vehicle with little ground clearance may be moved onto the loading frame 100 without damage.

The use of a pivotable coupling 150 to join the first and second actuators 130, 140 enables use of two extendable actuators (e.g. hydraulic rams) in series which can both extend and contract the loading frame as well as enable the low approach needed by being able to drop the pivot 22 defined by the pivotable coupling 150 below the tail end 114 of the tipping sub-frame 110 (as shown in Figure 14).

Additionally, the use of hydraulic or-the-like actuator arrangements as described allows for a system which wears inherently less than systems of the related art using, for example, a chain or rack and pinion arrangement instead.

Also, the configuration of the loading system vehicle is such that overall it may be lighter than a loading system of the related art, thereby increasing the potential payload of any vehicle to which it is attached.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims (18)

1. A loading system for a vehicle, comprising: a base unit; a loading frame carried by the base unit and pivotable relative to the base unit about a hinge, the loading frame comprising: a tipping sub-frame and a platform pivotably connected to one another by a pivotable platform coupling, a first actuator fixed to the tipping sub-frame, a second actuator fixed to the platform, and the first actuator and the second actuator are pivotably connected to each other by a pivotable actuator coupling; the actuators being operable to move the platform relative to the tipping sub-frame between a stowed configuration in which the platform is located on and supported along at least some of its length by the tipping sub-frame; and an extended configuration, in which the platform has been moved along the tipping sub-frame away from the stowed configuration, and is supported from the tipping sub-frame at least by the pivotable platform coupling.

2. The loading system according to claim 1, configured such that: the platform is pivotable relative to the tipping sub-frame about the pivotable platform coupling when the pivotable platform coupling and the pivotable actuator coupling are aligned.

3. The loading system according to claim 1 or claim 2, wherein the tipping sub-frame comprises a support rail which extends at least part of the length of the tipping sub-frame, wherein the platform is carried by the rail; and moveable relative to and along the rail.

4. The loading system according to any one of claims 1 to 3, wherein the pivotable platform coupling comprises a saddle, the saddle being mounted on, and movable along, the tipping sub-frame rail, and pivotably coupled to the platform.

5. The loading system according to any one of the preceding claims wherein the tipping sub-frame comprises a guide track which extends at least part of the length of the tipping sub-frame, and the actuator coupling is located in the guide track such that the first actuator is operable to move the actuator coupling along the guide track.

6. The loading system according to claim 5, wherein the guide track extends from a tail end of the tipping sub-frame to a location substantially halfway between the head end and tail end of the tipping sub-frame.

7. The loading system according to any previous claim, further comprising: a third actuator which is : pivotably coupled to the base unit, pivotably coupled to the tipping sub-frame of the base unit, and operable to pivot the loading frame relative to the base unit to thereby pivot the loading frame is about its hinge, and pivot the tipping sub-frame and platform relative to each other about the pivotable platform coupling.

8. The loading system according to any previous claim, further comprising: a control system configured to: perform a sequence of operations to change the loading frame from the stowed configuration to the extended configuration, and perform another sequence of operations to change the loading frame from the extended configuration to a stowed configuration.

9. The loading system as claimed in any one of the preceding claims wherein all of the actuators share a common drive unit.

10. The loading system according to claim 9 wherein at least one of the actuators is an hydraulic cylinder.

11. The loading system as claimed in claim 10 wherein all of the actuators are hydraulic cylinders.

12. The loading system as claimed in any of claims 9 to 11 wherein the drive unit comprises a source of pressurised hydraulic fluid; all of the hydraulic cylinders being in fluid communication with the source of pressurised fluid such that the drive unit is operable to supply all of the hydraulic cylinders during their operation.

13. A method of operating a loading system for a vehicle as claimed in any one of claims 1 to 12, comprising the steps of: operating the second actuator to move the platform along the tipping sub-frame until the pivotable platform coupling and the pivotable actuator coupling are aligned; operating the first actuator to move the platform further along the tipping sub-frame such that the pivotable actuator coupling and pivotable platform coupling are moved together towards the tail end of the tipping sub-frame.

14. A method of operating a loading system as claimed claim 13, further comprising the steps of pivoting the tipping sub-frame relative to the base unit, and pivoting the platform relative to the tipping sub-frame.

15. A vehicle comprising a loading system of any one of claims 1 to 12 operable by the method of claims 13 to 14.

16. A loading system for a vehicle substantially as hereinbefore described and/or as shown in the accompanying drawings.

17. A method of operating a loading system as substantially as hereinbefore described and/or as shown in the accompanying drawings.

18. A vehicle substantially as hereinbefore described and/or as shown in the accompanying drawings.