WO2004082991A2

WO2004082991A2 - Vehicle incorporating a load carrying well

Info

Publication number: WO2004082991A2
Application number: PCT/GB2004/001102
Authority: WO
Inventors: Peter Dibdin; Pauline Dawes
Original assignee: Middlegate Marketing Limited
Priority date: 2003-03-15
Filing date: 2004-03-15
Publication date: 2004-09-30

Abstract

A vehicle which defines a load-carrying well into which payload can be lowered on a vertically displaceable platform. The platform is mounted on support members such as flexible straps carried by the sidewalls of the well and is raised and lowered on the support members. The well may be located in a central well section of a trailer which also includes a front section defining a front load-carrying floor and a rear section defining a rear load-carrying floor. Longitudinal walls of the well section may be defined by sheet members fixed together by an insulating layer to define a load-bearing laminated beam. The rear section of the trailer may incorporate a load-carrying platform which may be loaded with payload, raised on a support platform, and then displaced over the well.

Description

VEHICLE INCORPORATING A LOAD CARRYING WELL

The present invention relates to a vehicle incorporating a load-carrying well.

Vehicles incorporating load-carrying wells are known. For example, published International Application No. WO 01/62542 describes vehicles including trailexs having a front section defining a front load-carrying floor, a rear section defining a rear load-carrying floor, and a central well section located between the front and rear sections. Arrangements are provided to enable payload to be lowered into the central well section, h use, additional payload can be loaded into the trailer by supporting payload in two layers, one lowered into the well and one located above the well.

In conventional trailers, structural strength is normally provided by a pair of beams extending along the full length of the trailer, those b earns supporting a flat load- bearing floor. Clearly if a well section is provided which must be open to enable f*Dr example pallets to be lowered into it the conventional simple beam frame cannot be provided as those beams would extend across the well. Structural strength must therefore be provided by structural members extending along the longitudinal sides of the vell and the above mentioned published specification shows how this can Ibe achieved in general terms by providing beams extending along the longitudinal sides of the trailer, those beams providing the central section extending downwards at tlie sides of the well section. Such beam arrangements necessarily must be substantial to provide the necessary structural strength and must therefore either make a significant contribution to the overall width of the vehicle or extend beneath the well and therefore significantly limit the depth of the well.

The above published patent also describes various arrangements for lowering paylo ad into the central well section of a trailer. These arrangements include vertically displaceable platforms which may be raised and lowered within the well section. Although not shown in detail, the platforms are moxxnted on vertically extendimg hydraulic actuators. Such hydraulic actuators necessarily occupy a significant amoont of space on either side of the well. This limits the dimensions of the well for a given outer dimension for the trailer.

Conventional trailers have been designed to comply with accepted dimensional requirements in terms of width, height and length. Payloads are generally carried on pallets the dimensions of which have been designed to fit within vehicles having standard-dimension load-carrying compartments. It would be impractical to expect users to accept a vehicle not capable of receiving standard-sized pallets and accordingly vehicle designers are constrained as to the extent to which equipment mounted on trailers can project into the standard load-carrying space. This becomes a major problem when considering thermally insulated vehicles large numbers of which are now used for the distribution of for example food products. Thus in trailers incorporating central well sections the mechanisms used for elevating load-carrying platforms within the well sections cannot project to a significant extent inwardly from the vehicle walls. Similarly, the structural integrity of the w^ell sections must be achieved without reducing the width of the available internal space. Finally, in order for the well sections to be of sufficient depth to enable standard- pallets to be stacked one above the other in the well section the depth of the well section must be as large as possible. This is a particular problem in refrigerated vehicles where generally chilled air is distributed from a front section of the trailer througli the space above the payload and therefore sufficient space must be left open above the well for the efficient circulation of chilled air even if two layers of pallets are stacked one above the other in the well section.

It is an object of the present invention to provide arrangements which make it possible to manufacture trailers and other vehicles incorporating well sections capable of receiving payloads of standard dimensions .

According to the present invention, there is provided a vehicle comprising a load- carrying well and at least one load-carryirxg platform which is vertically displaceable within the well to enable a payload to be lowered into the well;, wherein the or each platform is mounted on support members carried by sidewalls of the well, and means are provided for moving the or each platform relative to the sidewalls on the support members.

The support members may be flexible, for example being formed from straps of the type generally used for load restraint or the like. Such support members can be relatively thin, for example only a few millimetres, and therefore do not occupy much space inside the load-carrying well. Thus by suspending a platform on such flexible support members there is no significant reduction in the available space within the well section.

The flexible support members may extend downwards from anchorage points mounted on the well sidewalls. For example the well sidewaLls may be defined by sidewall plates. Each flexible member may be connected to a svxpport plate secured to the sidewall plate, for example by arranging the support member so as to define a loop extending around the support plate. The positions of the support plates may be adjustable on the sidewalls to adjust trie effective length of^" the flexible support members.

The flexible support members may be coupled to means carri&d by the platform for drawing the flexible members into a space beneath the platform. For example, each flexible member may extend around a roller carried by the platform and may be connected to a hydraulic actuator carried by the platform, the hydraulic actuator being extensible in a direction parallel to an upper surface of the platform. Hydraulic fluid may be supplied to the platform actuator by a piston and cylinder coupling one end of which is mounted on the platform and the other end of which is mounted on the well.

Arranging hydraulic actuators in the floor of the platform resuUts in a very efficient utilisation of the available space. This in turn makes it possible to lower a payload into the well to a depth such that there is still plenty of space above the payload for the circulation of chilled air in a refrigerated trailer. Each platform may support projections received within vertical guide tracks fitted to> the well walls. The guide tracks ensure the appropriate positioning of the platform. within the well. In addition, means may be provided for obstructing upper ends of the guide tracks so that, after a platform has been raised to an ele-vated position, the guide tracks may be obstructed so that the platform will be prevented from moving: downwards from the elevated position. Thus an inherently s afe mechanical structure is provided which will protect against accidental lowering of the platforms in the event for example of hydraulic failure.

In a first alternative arrangement, each flexible support member may extend from a. respective anchorage point on the platform and around at least one side wall mounted- pulley to an actuator located within the well. An anchorage point may be defmed. adjacent each corner of the platform, each anchorage point being connected to a, respective flexible support member in the form of a cable, all of the cables being guided by pulleys to a common actuator housed along one side of the well.

The actuator may support a first pulley which is displaceable relative to the well, the cables extending from anchorage points in the well and around the first pulley. In one arrangement, a first cable extends from the actuator, around a second pulley mounted in the said one side of the well above the actuator, around a third pulley mounted in. the side of the well, and around a fourth pulley mounted on a wall of the well above a. first platform anchorage point to which the first cable is connected, a second cable extends from the actuator, around the second pulley, around a fifth pulley mounted in the side of the well, and around a sixth pulley mounted on a ^"wall of the well above a. second platform anchorage point to which the second cable is connected, a third cable extends from the actuator, around the second pulley, around a. seventh pulley mounted on a wall of the well, and around an eighth pulley mounted on a wall of the well above a third platform anchorage point to which the third cable is connected, and fourth cable extends from the actuator, around the second pulley, around a ninth pulley mounted on a wall of the well, and around a tenth pulley mounted on a wall of^" the well ahove a fourth platform anchorage point to which the fourth cable is connected. In another arrangement, a first cable extends from the actuator, around a second pulley mounted on the said one side of the well above the actuator, around a third pulley mounted in the well above the second pulley, and around a fourth pulley mounted in the well above a first platform anchorage point to which the first cable is connected, a second cable extends from the actuator, around the second pulley., around a fifth pulley mounted in the well above the second pulley, and around a sixth pulley mounted in the well above a second platform anclxorage point to which the second cable is comiected, a third cable extends from the actuator, around a seventh pulley mounted in the well, around an eighth pulley mounted on one side of the well and across the floor of the well beneath the platform to a ninth pulley mounted in the opposite side of the well, and from the ninth pulley around a tenth pulley mounted in the well above a third platform anchorage point to which the third cable is connected., and a fourth cable extends from the actuator, around the second pulley, around an eleventh pulley mounted in the well, around a twelfth pulley mounted in one side of the well and across the floor of the well to a thirteenth pulley mounted in the opposite side of the well, and from the thirteenth pulley around a fourteenth pulley mounted in the well above a fourth platform anchorage point to which the fourth cable is connected.

The present invention also provides a vehicle comprising a front section defining a load-carrying front floor, a rear section defining a load-carr^ting rear floor, and a well section located between the front and rear sections, the well section including a thermally insulated well floor, thermally insulated transverse sidewalls extending downwards from the front and rear floors to the well floor, and thermally insulated longitudinal sidewalls extending between the well floor and the front and rear sections, wherein at least an upper portion of each longitudinal sidewall comprises inner and outer load-bearing sheet members separated by an insulating layer, the sheet; members being fixed to the insulating layer to define a load-bearing laminated beam extending between the front and rear sections.

The load-bearing laminated beam can provide great structural strength without; occupying a large space in the horizontal direction and whilst maintaining the integrity of the thermally insulated wall in which the laminated beam is incorporated. Once again therefore this arrangement ensures that the space within the well into which payload can be lowered is not restricted.

Each longitudinal sidewall may include a rectangular outer frame formed from sheet members, at least an upper part of that frame being fixed to the insulating layer to define the load-bearing laminated beam. Of course other sections of the rectangular outer frame may also be assembled to form laminated beams as desired.

The sheet members may be secured by screws driven into the insulating layer, the screws on opposite sides of the insulating layer being offset relative to each other to ensure their separation by a material forming the insulating layer. Thus the insulating characteristics of the beam are not compromised as a result of the screws fornxing thermal bridges through the insulating layer. The insulating layer may include a layer of polycarbonate into which the screws are driven.

The front and rear sections of the vehicle may comprise longitudinally extenϋng frame beams connected to transverse frame beams, the transverse frame beams being secured to the transverse sidewalls of the well section.' The transverse frame beams may he connected to an inner transverse wall of the vell by thermally insulating connectors, for example connectors defined by spaced apart plates extending from the transverse frame beam and the well wall, the plates being interconnected by a bolt passing through the apertured plates, and the bolt being thermally insulated from the plates.

The present invention also provides a vehicle comprising a first section defining a load-carrying front floor, a rear section defining a rear floor, a well section located between the front and rear sections, and means for lowering payload into the well section, wherein a support platform is vertically displaceable above the rear floor between raised and lowered positions, and the support platform carries a load-carrying platform which is horizontally displaceable over the well when the support platform is in the raised position, the load-carrying platform being displaceable from the support platform onto supports mounted on sidewalls of the vehicle.

Thus a simple and robust mechanism is provided which enables payload to be lifted up and moved over the well section. This is achieved by using low-profile supports in the sidewalls, avoiding any significant reduction in trie internal width of the vehicle available for receiving payload.

Rollers may be interposed between the support platform and the load-canying platform and between the sidewall support and the load-carrying platfonn. For example, the load-canying platform may support rollers along its longitudinal edges which run on tracks extending along longitudinal edges of the support platform. The sidewall supports may include rollers on which formations on the longitudinal edges of the load-carrying platform roll. The sidewall support rollers may be mounted on plates defining inner sidewalls of the well section.

The support platform may carry a drive motor for displacing the load-carrying platform over the well. The drive motor may drive a roller which rotates a ove an axis transverse to the vehicle, which projects above an upper surface of the support platform, and which frictionally engages the surface defined by the load-carrying platform such that rotation of the roller drives the load carrying platform relative to the support platform.

Another aspect of the invention provides a vehicle comprising a load-carrying well, at least one load-carrying platform which is displaceable within the well to enable a payload to be lowered into the well, and lifting means operable to raise and louver the platform within the well, the lifting means comprising at least one scissor lift. The scissor lift may comprise at least one pair of crossed support members (elongate arms, beams, rods etc.) pivotally connected together, and actuator means operable to control the relative angular orientation of the crossed support members. The support members are then coupled to the platform and to the well such that as their angular separation is increased by the actuator means, the platform is driven upwards. Lri prefened arrangements the platform is hingedly coupled to a first one of the pair of support members (by suitable means) and is arranged to rest on a second one of the pair of support members (directly, or on a roller carried by an end o the support member, for example), such that the platform can be lifted from the second support member to permit access to the lifting means beneath the platform.

Preferably, the lifting means is arranged to maintain the platform, substantially horizontal (if the vehicle itself is horizontal) as the platform is raised or lowered.

Preferably, the liftmg means is carried, at least partially, by sidewalls of the well, and these sidewalls are preferably longitudinal sidewalls of the well. Thus, it is preferred that the lifting means is not carried entirely by the floor of the well, which may be an insulating panel having low strength. The load on the lifting means is preferable spread to the sidewalls, and/or to strong longitudinal beam members ru nning down sides of the floor / base panel.

The vehicle may comprise a transverse beam arranged forward of the platform and a transverse beam arranged rearward of the platform, the transverse beams extending from one well sidewall to the opposite well sidewall, the transverse beams supporting at least one longitudinal support member, the lifting means being supported by the at least one longitudinal support member. In such cases, end portions of t xe transverse beams are preferably arranged to be supported by or proximate to the sidewalls, and central portions of the transverse beams are not directly supported, in particular they axe not in contact with central part of the floor of the well. Each tranverse beam may be part of a respective transverse partition in the well.

Certain embodiments comprise at least two said platforms, each having associated with it a respective lifting means, the platforms being spaced apart longitudinally in the well by a transverse partition. The transverse partition may extend across the well, from one sidewall to the opposite sidewall. Preferably, the transverse partition is connected to the sidewalls such that at least a portion of any vertical load applied to the transverse partition is transmitted to the sidewalls, and the transverse partition may comprise a load-bearing upper surface arranged to be substantially level with a floor of the vehicle adjacent the well. It will also be level with the upper surface of the well platform when that platform is in the raised position.

Certain embodiments comprise a plurality of s aid transverse partitions spaced apart longitudinally in said well, a respective platform, being ananged between each pair of adjacent partitions, and the lifting means associated with each platform is supported by the respective pair of transverse partitions. Each transverse partition is preferably supported by sidewalls the well.

Preferred embodiments may utilise a pneumatic actuator arranged to drive the scissor lift. This pneumatic actuator may comprise at least one expandable air bag.

Embodiments of the present invention will no be described, by way of example, -with reference to the accompanying drawings, in which:

Figures 1 A to ID illustrate the loading of pallets into a first trailer embodying the present invention which is intended to transport standard British pallets loaded onto the trailer by a forklift truck;

Figures 2A to 2F illustrate the loading of standard European pallets onto a trailer embodying the present invention;

Figure 3A to 3F illustrate the loading of rolL cages onto a trailer embodying the present invention;

Figures 4A to 4F illustrate the loading of standard British pallets onto a further trailer embodying the present invention; Figures 5A and 5B illustrate a mechanism for adjusting the floor level of a rear trailer section in an embodiment of the present invention;

Figures 6 to 15 illustrate details of a rolling and vertically moveable platform which may be embodied in a trailer in accordance with the present invention;

Figure 16 illustrates sub assemblies which may be incorporated in a trailer embodying the present invention;

Figures 17, 18 and 19 illustrate details of one sub assembly shown in Figure 16;

Figures 20 to 34 illustrate details of a well subassembly shown in Figure 16;

Figures 35 to 38 illustrate details of bracing arid guide assemblies incorporated in the well shown in Figure 16;

Figures 39 to 42 illustrate details of platforms which may be raised and lowered within the well;

Figures 43 and 44 illustrate platform suspension arrangements used within the well;

Figures 45 to 47 illustrate a hydraulic supply connection for coupling hydraulic fluid to actuators within the platforms;

Figures 48 to 51 illustrate details of platform support arrangements in the sidewalls of the well structure;

Figures 52 to 55 illustrate support bar assemblies which may be clipped to the sidewall arrangements illustrated in Figure 48; Figures 56 to 61 are schematic representations of an alternative platform support arrangement in which a platform is supported on cables extending around a series of pulleys; and

Figures 62 to 69 illustrate a further alternative anangement in which again a platform is supported on cables extending around pulleys.

Figure 70 is a side view of the rear platforms and lifting mechanism of a trailer embodying the invention, in the initial lowered, loading position;

Figure 71 is a side view of the assembly of figure 70, but in an elevated position;

Figure 72 is a rear view of the elevated assembly of figure 71;

Figure 73 is a rear view of the lowered assembly of figure 70;

Figure 74 is a sche atic longitudinal sectional view of part of a vehicle embodying the invention;

Figure 75 is a schematic cross section, along line A- A, of the vehicle shown in fig. 74;

Figure 76 is a schematic side view of the well lifts of a trailer embodying the invention;

Figure 77 is a schematic cross section of the platform and one of the scissor lifts from fig 76;

Figure 78 is another cross section showing the lift lowered;

Figure 79 is a schematic side view of the trailer of figs 76 to 78 with the well lifts down, and the trailer loaded; Figure 80 is a schematic cross section of the fig 76 trailer, showing the partition structure; and

Figure 81 is an enlarged view of the portion P from fig 80.

Referring to Figures 1 A to ID, this illustrates the loading of cargo on pallets into a trailer in accordance with a first embodiment of the present invention. A front section of the trailer supports a conventional towing hitch 1 and a rear section of the trailer supports three axles each canying wheels 2. A well 3 is defined between the front and rear sections of the trailer and three latforms 4, 5 and 6 maybe moved vertically within the well between an upper position, as shown in Figure 1 A and a lower position as shown in Figure ID.

As shown in Figure 1A, initially cargo is loaded into the trailer so that four pairs of pallets 7 occupy the front section of the trailer. A further pair of pallets 8 are then loaded onto the platform 4. The platform 4 is then lowered into the well 3, and a further pair of pallets 9 are mounted on support bars 10 inserted above the pallets 8, the support bars extending across the width of the trailer and being supported at each of their ends by the walls of the trailer. A further pair of pallets 11 are then loaded onto platform 5 to result in the configuration shown in Figure IB.

The platform 5 is then lowered and a further pair of pallets 12 are mo nnted on support bars 13 extending across the width of the trailer. A further pair of pallets 14 are then loaded onto the platform 6. The result is illustrated in Figure lC.

To complete the loading process, the platform 6 is lowered into the well, two pairs of pallets 15 and 16 are mounted above the pallets 14 on support bars 17, and five further pairs of pallets 18 are loaded into the rear section of the trailer. The assembly is then fully loaded. In an alternative embodiment of the invention illustrated in Figures 2A to 2F, once again the illustrated trailer comprises a front section and a rear section separated by a well 3 within which three vertically moveable platforms 4, 5 and 6 are located. Initially the platforms 4, 5 and 6 are aligned with the floor of the front section of the trailer and with an upper surface of a vertically and horizontally moveable platfonn

19 supported in the rear section of the trailer. The platform 19 is mounted on a support platform 20, the support platform 20 being moveable in the vertical direction so as to elevate the platform 19, and the platform 19 being displaceable in the horizontal direction after the support platform 20 has been elevated.

As shown in Figure 2B, initially ten pairs of pallets 21 are loaded into the trailer. The platforms 4, 5 and 6 are then lowered as shown in Figure 2C, and the support platfonn

20 is elevated as shown in Figure 2D. The platform 19 is then rolled forward onto supports provided in the trailer walls and the platform support 20 is lowered so that an upper surface defined by the platform is aligned with a short floor surface 22 at the entry end of the trailer. Further pallets 23 are then loaded into the rear section of the trailer.

Figures 3 A to 3F illustrate an arrangement similar to that of Figures 2A to 2F but in which only two platforms 24 and 25 are provided within well 3. The illustrated configuration is appropriate for the lo ding of roll cages rather than pallets. As in the case of the embodiment of Figures 2A. to 2F, platforms 24 and 25 are initially elevated and the trailer is filled with roll cages. The platforms 24 and 25 are then lowered (Figure 3C) and roll cages loaded into the rear section of the trailer are then raised and moved forward over the platforms 24- and 25. The final loading of the trailer is then completed by loading roll cages into the rear section of the trailer.

Referring now to Figures 4A to 4F, this shows an arrangement very similar to that illustrated in Figures 2A to 2F, but whereas the anangement of Figures 2A to 2F is appropriate for carrying pallets of standard European dimensions the arrangement of Figures 4A to 4F is designed for carrying pallets having the dimensions of standard British pallets. Once again, in the e bodiment of Figures 4A to 4F pallets initially loaded in the rear section of the trailer are raised and pushed forwards over previously loaded pallets which have been lowered into the well 3.

Details of the structures and mechanisms which make it possible to manufacture trailers capable of the operations described with reference to Figures 1 to 4 are given in the following description. The first detail to be described with reference to Figures 5 A and 5 P. is that which enables the combination of platform 19 and support platfonn 20 of Figures 2A to 2F to be initially positioned so that the upper surface of platform. 19 is aligned with floor section 22 (see Figure 2A) and then for the upper surface o f support platform 20 to be aligned with floor section 22 (Figure 2E).

Referring in detail to Figures 5A and 5B, the rear section of the trailer comprises beams 26 supporting an insulated floor 27 and extending between insulated sidewalls 28. The support platform 20 (see Figures 2A to 2F) is mounted on vertically displaceable support beams 29 above the floor 27 such that the support platform 20 can be moved in the direction indicated by arrows 30. Two pairs of blocks 31 are supported on a slide above the floor 27 and coupled to a hydraulic actuator 32 so as to be displaceable from the position shown in Figure 5A to a position (not shown) in which the blocks are located vertically beneath the beams 29.

When the platform 19 is in its initial position as shown in Figure 2 A, the blocks 31 are) in the position shown in Figure 5 . so that the beams 29 can be lowered into contae with the floor 27. After the support platform 20 has been raised and the platform 19 has been displaced over the well of the trailer, the blocks 31 are moved to the left in Figure 5 . until they are located beneath the beams 29. The support platform 20 is then lowered until the beams 29 rest on the blocks 31. As a result the upper surface o f the support platform 20 now assumes the vertical position initially assumed by the upper surface of the platform 19, that is aligned with the surface 22 (Figure 2E). Thus a simple mechanism is provided which ensures that the surface onto which a forklift truck or the like has to be driven is vertically aligned with the edge of the trailer floor adjacent the entry end of the trailer. Vertical displacement of the support platform 20 may be achieved using hydraulic actuators (not shown) extending vertically beneath the floor 27, or any other convenient means, for example and arrangement si ilar to that described below which is used to vertically displace platforms within the well section of the trailer.

Referring now to Figures 6 to 15, details of one anangement for enabling the platform 19 of Figures 2A to 2F to be pushed forward within the trailer will be describ»ed. Figure 6 shows the upper horizontally displaceable platform 19 after it has been pushed forward partially relative to the lower support platform 20. Each edge of the platform 19 carries a row of rollers 33 (Figure 13) which are aligned with a flat roller track 34 extending along a respective edge of the support platform 20. The rollers 33 are carried in a support beam 35 connected to an outwardly projecting angle 36. Xhe lower edge of angle 36 is intended to run on rollers provided in the sidewalls of the trailer above the well. The support platform 20 is reinf rced by side beams 37 located beneath the tracks 34.

Figure 11 shows one edge of the platform 19 after it has been displaced from its ini'tial position above the support platform 20 onto supports provided on the trailer walls. A plate 38 secured to an inner wall of the trailer carries rollers 39 which are loca_ted behind a cover plate 40. A series of rollers is provided along each side of the trailer wall above the well so as to provide a roller track onto which the angle 36 supported by the platform 19 can be displaced. When the platform 19 is fully supported on the rollers 39 the rollers 33 carried by support beams 35 are not in contact with any support surface.

Various mechanisms may be provided for applying a force to the platform 19 so as to displace it on and off the support platform 20. Simple motor and chain drive assemblies could be provided in the support platform 20 but an alternative anangement is illustrated in Figures 6 to 10 in the form of a motor 41 driving a wh_eel 42 which projects upwards through an aperture in the sπpport platform 20 as shown in Figure 8. The wheel 42 is positioned at the front edge of the support platform 20 so as to bear against the underside of a beam 43 extending along the length of "the platform 19. The beam 43 supports a rubber strip 44 against which the wheel 42 bears. There is good frictional engagement between the wheel 42 and the strip 44 and thus simply by driving the motor 41 the platform 19 can be driven as appropriate on to and off the support platform 20.

Referring now to figure 16, this illustrates the structure of the frame which supports the components of the trailer illustrated in for example Figures 2 A to 2F. _A front subassembly 45 is coupled to a well assembly 46 which in turn is coupled to a rear subassembly 47 canying the running gear. To assist understanding, the subassemblies 45 and 47 are shown spaced from ^"the well assembly 46 in Figure 16 but it will be appreciated that the three main components will be united as indicated by arrows 48.

Details of the front subassembly 45 as shown in Figure 16 are illustrated in Figures 17, 18 and 19. The front subassembly comprises a pair of beams 49 of I section which are welded to a box section beam 50, the box beam 50 in turn being connected to vertically extending angle members 51. The towing hitch 1 will be connected in the position shown in Figure 18 to an appropriate support structure extending between the beams 49, that support structure not being shown in Figure 17.

Figure 20 to 34 illustrate the structure of the well assembly 46 of Figure 16.

Figure 20, 21 and 22 illustrate the construction of an underlying well frame from eight lengths of angle, comprising lengths 52 which extend along the lower side edges of the "well, lengths 53 which extend along front and rear lower edges of the well, and lengths 54 which extend upwards from each of the four corners of the rectangular frame. The framework of Figures 20, 21 and 22 is then supplemented by an assembly of plates shown in Figure 23 and 24, the angles 52₌ 53 and 54 being shown in broken lines in Figures 23 and 24. The assembly of plates comprises a relatively wide upper plate 55, vertically extending side plates 56 and lower plate 57. The outer frame structure described with reference to Figures 20 to 24 receives an inner well wall structure as illustrated in Figures 25 to 30. The underside of the floor of the inner well structure comprises a 1mm thick steel sheet 58 (Figures 28 and 30) which overlaps the inwardly extending edge of the frame that is made up from the angles 52 and 53 (Figure 20). A 4mm thick layer of ply 59 is laid on the sheet 58, then a three layer section of insulating styrofoam is laid on the ply 59, the three sheets being labelled 60, 61 and 62. The foam layers 6O to 62 extend across the full width of the base of the well between timber spacers 63 resting on the frame members 52, 53. A cover layer in the form of a further 1mm thick steel sheet 64 and a further 4mm thick ply sheet 65 extends over the upper layer 62 and over the timber spacers 63. Mounted on the steel sheet 64 is a further frame made of angle 66 the upwardly extending parts of which support a steel plate 67 which is 6mm thick.

As shown in the longitudinal section of Figure 27, the front and rear inner well plates 67 extend vertically upwards to end flush with the level of the front section of the trailer floor. In contrast, as shown in the transverse section of Figure 29, the plates 67 which extend along the sidewalls of the well extend above the level of the trailer floor the position of which is represented by the broken line 68 in Figure 29 and by the upper surface 69 of the front floor section 70 of the trailer as shown in Figure 27.

The sidewalls of the well are covered with a lmm thick sheet of steel 71 as best indicated in Figure 31. The laminated assembly shown in Figure 31 provides structural strength to the well such that the well can support the loads transmitted through it between the front and rear trailer svxb frame assemblies 45 and 47 (see Figure 16). Figure 31 shows that the upper plate 55 (Figures 24) is covered by the steel sheet 71 and defines a large number of counter sunk holes through which screws 72 extend. Similarly, the vertically extending steel sheet 6 defining a sidewall of the well defines a series of countersunk holes receiving screws 73. Sandwiched between the plates 67 and 55 is a three-layer body of thermal insulation made up from a 20mm thick layer 74 of high density load bearing styrofoam, a 10mm thick layer 75 of polycarbonate, and a further 20mm thick layer 76 of high density load bearing stryofoam. The screws 72, 73 ensure that the multi-layer assembly is locked together without the screws providing a thermal bridge between the inner and oixter skins of the well. Thus thermal insulation is maintained whilst at the same time the assembly provides the necessary structural strength to the overall trailer frame.

As can be appreciated best from Figure 29, the sidewalls of the well wliich extend above the trailer floor level indicated by line 68 are made up in part of a vertical extension of the 10mm thick polycarbonate layer 75 shown in Figure 31. The detail of this upper section of the well sidewalls is shown in Figure 32. Again in Figure 32 the broken line 68 indicates the trailer floor level.

The polycarbonate 75 is sandwiched between a 20mm thick layer 77 of high density load bearing styrofoam and a 9mm thick sheet of plywood 78. A further layer 79 of 20mm thick high density load bearing styrofoam is located on the outside of the ply 78 and inside a 1mm thick outer skin 80 of the trailer.

Referring to Figures 33 and 34, this shows the interconnection between the well assembly and the rear subassembly 47 (see also Figure 16). The rear subassembly 47 comprises longitudinally extending beams 81 which are secured to a box section cross beam 82 from the ends of which angles 83 extend vertically downwards. The beam 82 is connected to the frame of the well assembly 46 by connectors 84 details of Λvhich are shown in Figure 34.

Referring to Figure 34, spaced apart stainless steel brackets 85 are mouuited on the well frame. A stainless steel bracket 86 is rrxounted on the cross beam 82. The brackets 85 and 86 define apertures which received insulating collars 87 through which a bolt 88 extends. Insulating washers 89 maintain separation between the brackets 85, 86 and the bolt 88. Thus the well frame and rear subassembly 47 are securely interconnected but thermally insulated from each other. Similar connectors 84 are provided between the well frame and front sub frame 45 (see figςure 16). In addition the angles 51 and 83 are bolted to the well frame. As a result the overall assembly is extremely robust and well able to cope with the bending moments that will be applied to the trailer frame in use. Within the well assembly as described above additional components are provided for guiding and separating the vertically moveable platforms which are received within the well. In the described embodiment there are three vertically moveable platforms in which case there are guide structures at both the front and rear ends of the well and two guide structures spaced apart along the length of the well. Figures 35, 36 and 37 illustrate one of the two structures which are spaced apart along the length of the well. Each of these structures provides additional strength to the well as it in effect forms a brace extending across the width of well.

Referring to Figures 35 to 37, the bracing sections comprise bottom pLates 90 which will be welded to the inner skin of the well floor, upstanding plates 91 which extend a short distance vertically from the plates 90, and side members each made up from an assembly of four box sections 92, 93, 94 and 95. Slots 96 are defined between the box sections 94 and 95 to provide guides for adjacent vertically moveable platforms. The box sections 92 and 93 will when installed be welded to the inner skin of the well body. Bracing frames comprising horizontal beams 97, diagonal beams 98 and vertical plates 99 provide appropriate bracing to the assembly. Plates 100 provide a surface to which a cross plate (not shown) can be bolted so as to define a nanow section of the trailer floor between adjacent moveable platforms when the platforms are flush with the front and rear sections of the trailer floor.

Referring to Figure 38, this shows a guide structure one of which is located inside both the front and rear walls of the well. It also shows a platform locking mechanism which will secure the platforms in the raised position even in the event of the failure of the associated control system. In Figure 38, vertically extending components similar in structure to the box sections 92 to 95 of Figure 36, define vertically extending slots 101 which serve as guides for projections extending from the adjacent moveable platform. At the top of each of these slots there is a spaced-apart pair of plates over which is slideable a locking member 102 carried by a locking bar 103 the position of which is controlled by a hydraulic actuator 104. The configuration at the upper end of each slot 101 is thus the same as the configuration at the top of each slot 96 of the intermediate bracing assemblies shown in Figure 35. With the locking members 102 in the position shown in Figure 38, projections on an adjacent platform can be carried upwards to a position above the locking member 102, at which point the actuator 104 can be energised so as to move the locking member 1 02 over the top of the slot 101. Thereafter the platform cannot be lowered until the locking bar 103 has been retracted to the position shown irx Figure 38. It will be appreciate that a locking mechanism equivalent to that shown in Figure 38 is provided at each end of the well and on each of the intermediate bracing assemblies such as that shown in Figure 35.

Referring now to Figures 39 to 41, this shows the configuration of one of the three platforms which is vertically displaceable w thin the well. Each platform comprises an upper plate 1O5 which when the platform, is in its locked raised position is aligned with the front and rear sections of the trailer floor. The upper plate is connected by reinforcing plates 106 to cross members 107^" the ends of which support projections in the form of plates 108 with bracing members 109. The projections 10S are located so as to run in the slots 101 in the end guide members (see Figure 38) or the slots 96 in the intermediate bracing members (Figures 3 5).

Referring now to Figures 42 to 44, this illustrates the mechanism used for elevating one of the three platforms received within the well. As shown in Figure 39, each platform incorporates six reinforcing plates Tbetween which five elongated spaces 110 to 114 are defined. The central space 112 is shown in Figure 42 as being empty but in fact receives a hydraulic connection assembly to be described below. The two outer most spaces 110 and 114 receive hydraulic actuators which are used to control the elevation of one side of the platform, whereas the two spaces 111 and 113 receive hydraulic actuator assemblies which control the elevation of the other side of the platform. Each of the four hydraulic actuator assemblies is connected to a flexible strap which extends from the hydraulic actuator around a respective roller 115 and upwards across the inner face of the inner vv^all of the well to an anchorage point 116 above the vehicle floor level which is indicated by a line 117. With the actuators fully extended as shown in Figure 43, the platform is suspended a short distance above the base of the well. If the actuators are then energised so as to pull the actuators inwards, thereby dragging the straps progressively further into the moveable platform, the platform is pulled up until it assumes the position shown in Figure 44. Thus all of the active hydraulic components are carried within the platform and there are no complicated mechanical linkages. The suspension of the moveable platfonn in this manner in combination with the simple guide channels engaged by the projections 108 of Figure 39 ensure that the platforms can be reliably raised and lowered. The locking mechanism described with reference to Figure 38 ensures that once the platforms have been raised they can be locked in the raised position without requiring continuing energisation of the hydraulic actuators.

It is of course necessary to deliver hydraulic fluid to the actuator shown in Figure 42. This is achieved by the mechanism illustrated in Figures 45 to 46 which is received in the space 112 beneath the platform.

Referring to Figure 45, this shows a bottom mounting plate 118 which in practice would be secured to the inside of the inner floor of the well assembly. A hydraulic feed 119 delivers pressurised hydraulic fluid to a pivotally supported t-connector 120 in communication with the inside of a hydraulic cylinder 121 arid from that cylinder through a piston 122 to a further hydraulic t-connector 123. The hydraulic t- connector 123 is mounted on a plate 124 fixed to the moveable platform in the space 112 (Figure 42). With the platform in the lowered position (Figure 43) a side view of the assembly of Figure 45 is as represented in Figure 46. As the platform rises, the plate 124 is pulled upwards with the platform so that the assembly assumes the configuration shown in Figure 47. The piston and cylinder arrangement 121, 122 is arranged such that no axial force is delivered by the hydraulic assembly of Figures 45 to 47 which therefore simply acts a mechanism for delivering pressurised hydraulic fluid to the actuators mounted on the platform.

Referring now to Figures 48 to 51, Figure 48 is an elevation of a steel plate which defines the inner sidewall of the well, anchorage points for the straps which support the three platforms, and recesses for receiving the ends of support bars to be described below. Thus the plate shown in Figure 48 corresponds to the plate 67 shown in Figure 30.

Referring to Figure 48, the plate 67 defines six apertures 125 edges of which define rows of offset screws holes 126 to which strap supports 127 can be secured. The strap supports 127 are in use inserted in permanent loops formed in the ends of the platform straps. As shown in Figure 50, the supports 127 also define offset apertures 128. The apertures 126 and 128 are provided to enable the positioning of the supports 127 at different locations along the length of the apertures 125 so as to compensate for any manufacturing tolerances when the straps that are used to support the platforms are manufactured. The pitch between the apertures 128 is twice the offset between the sets of apertures on opposite sides of the support, the same relationship applying to the offset between the apertures 126 on opposite sides of the same aperture 125. This means that by appropriate reversal of the supports 127 the vertical position of the supports 127 can be adjusted by half the pitch of the spacing between adjacent apertures 128. Thus when the movable platforms are being installed the platform support straps are pulled tight and the support plates 127 are fitted in as high a position as is possible given the length of the associated straps. Appropriate distribution valves will also be required in the hydraulic circuits (assuming that all the hydraulic actuators and the platforms are driven from a single hydraulic source) so as to ensure that the platforms remain substantially horizontal as they are elevated.

The plate 67 also defines apertures 129 across each of which is welded a plate 130. Thus the plates 130 extend across a lower section only of the apertures 129. Insulation immediately behind the apertures 129 is also cut away to enable a support bar end to be pushed a short distance through the aperture 129.

Figures 52 to 55 illustrate the manner in which a cargo support bar may be engaged with the plates 130 extending partially across the apertures 129. Figure 52 shows a support bar 131 which is a simple square box section and supports a hook member on each of its ends. The hook member is defined by an end plate 132 which closes off the end of the box section, a spacer plate 133, and a hook plate 134, the hook plate 134 being secured to the space plate 133 so as to define a slot 135 with the end plate 132. The hook assembly shown in Figure 52 is intended to be insertable through the section of an aperture 129 as shown in Figure 53 above one of the plate 130 which partially closes off the aperture 129.

Figure 54 illustrates the positioning of a support bar as shown in Figure 52 so that the support bar extends across the well between two of the apertures 129 on opposite sides of the well. Sides of the well are indicated by broken lines 136 and the recess located behind the apertures 129 is indicated by the broken line 137. Initially the support bar is positioned with both of its ends extending into the facing recesses above the plates 130 as shown in Figure 54. The support bar is then pulled downwards to the position shown in Figure 55 so that the hook plates 134 engage over and in effect lock relative to each other the plates 1 30 which are located on opposite sides of the wells. Not only does the positioning of a support bar in this manner enable the positioning of cargo on the support bars in the manner described with reference to Figures 1A to ID, but in addition the support bars provide further bracing between opposite sides of the well assembly.

It will be appreciated that in embodiments of the invention in which cargo can be loaded onto a platform such as the platform 19 of Figure 2 for subsequent movement over the well it will not be necessary to provide support bars. However in some circumstances it may be advantageous to fit a trailer with a platform such as the platform 19 of Figure 2 and also provide the facility to receive support bars such as those illustrated in Figures 52 to 55 so as to provide maximum flexibility to a vehicle operator.

In the embodiment of the invention described above, load-carrying platforms are supported on straps which extend above the level of the raised platforms and which are connected to actuators that move vertically with the platforms. Alternative arrangements are however possible in which actuators are mounted within the well rather than to be displaceable with the platform relative to the well. Two such anangements are described with reference to figures 56 to 61 and 62 to 69 below.

Referring to Figure 56, trailer side walls 138, 139 hawe located there between a rectangular platform 140 which is vertically displaceable relative to the walls 135 and 139 on four cables, that is a first cable 141, a second cable 142, a third cable 143 and a fourth cable 144. An end wall of the well within which the platform 140 is movable is represented behind the cables 143 and 144. The other side of the well is defined by a partition only a base section 145 of which is shown. That partition supports a hydraulic actuator comprising a cylinder 146 and a ram 1 -47 which can be extended as shown in Figure 56 or retracted as shown in Figure 57_ The four cables extend to anchorage points 148 which are fixed to the partition.

Each of the four cables 141, 142, 143 and 144 extends from the anchorage points 148 around a first pulley 149 and then to a second pulley 150 which is fixed to the partition above the actuator.

The four cables follow different routes from the second pulley 150. The first cable 141 extends vertically upwards from the second pulley 130 to a third pulley 151 such that the cable 141 follows a substantially vertical track between the pulleys 15C* and 151. The first cable 141 passes around the pulley 151 and then follows a horizontal path to a fourth pulley 152 mounted on the side wall of^" the trailer body. The cable

141 then extends vertically downwards to a first anchorage point defined by a pin 153 extending from the side of the platform 140.

The second cable 142 extends vertically adjacent the cable 141 from the coirxmon second pulley 150 to a fifth pulley 154 supported at the side of the well. The cable

142 then extends horizontally to a sixth pulley 155 which is mounted on the side wall of the trailer and from the pulley 155 to a second anchorage point defined by a pin 156 extending from the platform 140. The third cable extends from the common second pulley 150 to a seventh pnlley 157 (see Figure 57) and then extends horizontally along the side of the trailer to an eighth pulley 158. The third cable 143 then extends vertically downwards to a third anchorage point defined by a pin (not shown) extending from the platform 140.

The fourth cable 144 extends from the common second pulley 150 to a ninth pulley 159 located on the other side wall of the trailer. The cable 144 then extends from the pulley 159 to a pulley 160 and downwards therefrom to a fourth anchorage point (not shown) supported on the platform 140.

Figure 56 shows the platform elevated, that is with the ram 147 fully extended, thereby pulling on all four cables and pulling the platform up to the sets of pulleys mounted on the trailer side walls. In contrast Figure 57 shows the ram 147 fully retracted, enabling cable to the paid out around the common second pulley 150 so as to lower the platform 140 to the base of the well within the trailer.

Thus in the embodiment of Figures 56 to 61 , as compared with the previously described embodiment of the invention, the platform is suspended on cables rather than straps, the cables extending over pulleys supported by side walls of the well rather than extending downwards from anchorage points in the side walls of the well. An additional difference is that, rather than supporting the hydraulic actuator in the vertically movable platform itself, the actuator is mounted in a side wall off^" the well which extends transversely of the main trailer body within which the platform is supported. It will be noted that the side wall — mounted pulleys are mounted in the well side walls which extend parallel to the exterior side walls of the trailer in which the platform is fitted. Alternative arrangements are possible however, for example anangements in which the platform is suspended on cables extending around pulleys mounted on side walls of the well which extend transversely with respect to the trailer in which the platform is mounted. One such arrangement will now be described with reference to Figures 62 to 69 of the accompanying drawings. Referring to Figure 62, this is a schematic plan view of a well defined within a trailer in which well three independently displaceable platforms 161 are mounted. The platforms extend across the width of a trailer, the inner skin of side walls of the trailer being represented by lines 162. One end wall of the well is defined by a wall 163, the other end of the well is defined by a partition 164, and two further partitions 164 also extend transversely across the well. Each of the partitions 164 houses a hydraulic actuator 165, each actuator controlling the raising and lowering of an adjacent platform 161.

Referring to Figure 63, each actuator supports a first pulley 166 around -which four cables pass, each of those four cables running around a respective set of pulleys to connect to an anchorage point secured to a transverse edge of the respective platform adj acent a respective corner of the platform. A first cable 167 extends around a co mon roller 168 and then substantially vertically upwards to a pulley 169 mounted in the partition. The cable 167 then extends over a further pulley 170 adjacent the end of the partition, the cable being secured to a first anchorage point 171 mounted on the platform 161. A second cable extends from the common pulley 168 around pulleys 172 and 173 to an anchorage point 174 adjacent thte opposite end of the platform 161 from the anchorage point 171. A third cable 175 ezxtends around a seventh pulley 176 to an eighth pulley 177. The cable then extends beneath the platform to a ninth pulley 178 and upwards to a tenth pulley 179, the cable extending downwards from the pulley 179 to an anchorage point (not shown) on the platform. The platform is shown in Figure 64 in a lowered position to assist in understanding the pulley arrangement. A fourth cable 180 extends around an eleventh pulley 181 and a twelfth pulley 182, the cable 180 then extending beneath the platform to the opposite side of the well and being guided around a thirteenth pulley (not shown) adjacent the far edge of the well so as to extend upwards to a fourteenth pulley 183, the cable extending from the pulley 183 to an anchorage point on the platform. Thus all four corners of the platform are securely supported on a respective cable, each cable extending around pulleys supported on partitions defining side walls of the well. It will be appreciated that the two central partitions 164 shown in Figure 62 carry pulleys supporting cables which support the platforms on both sides of those partitions. The end partition 164 and the end wall 163 support pulleys which carry cables connected to a single adjacent platform 161.

Figure 67 is a side view of one of the partitions 164 before pulleys and the hydraulic actuator have been mounted thereon. Figure 68 shows the partition after pulleys and the actuator have been mounted thereon, and Figure 69 is a section tlirough figure 67 on the line 69-69. It will be seen that the partition comprises end plates 184 which will be secured by for example welding to the inner skin of the side walls of the trailer. An inverted U-section channel 185 extends along the top edge of the partition, the upper surface of that channel being aligned with the upper surface of^" the platforms when the platforms are in the elevated position. Each partition comprises a lower beam 186 defining an aperture 187 which receives an actuator assembly 165 as shown in Figure 68.

Figures 70 to 73 show the lifting mechanism for the support platform 9O0 of a vehicle embodying the invention. The support platform 900 is lifted by arx anangement comprising first and second pneumatically actuated scissor lifts (which may also be refened to as scissor jacks) and an air-bag (or pneumatic jack) arranged between them. The arrangement is shown in the collaps ed state in figure 70, and in the raised, elevated state in figure 71 (in which the upper platform [load-carrying platform] 1000 is brought into alignment with the side wall supports / tracks so that it can de driven forwards, over the well). As can be seen from figure 70, the advantage of the scissor lift arrangement is that it can collapse to a very flat configuration, and so takes up a small volume in the trailer/vehicle. Lool img at figure 71, the two scissor lift assemblies are spaced apart along the length of the trailer/ vehicle. Their construction and operation are the same, so only the forward lift will be described in detail. The forward lift comprises a first beam 9210 (support member) connected to a second beam 9220 by a pivot 830. Third and fourth beams are located behind the first and second in the figure, spaced apart across the -trailer width. A first end of the first beam 9210 is hingedly attached to an anchor point 940 which in turn is rigidly attached to a base plate 9400 secured to the trailer chassis. The opposite end of beam 9210 carries a roller 960 which engages an underside surface of the support platform 900. The second beam 9220 is hingedly coupled at one end to an anchor 950 attached to the underside of the support platform 900, and the opposite end carries another roller which is free to roll over a flat roller plate 970 attached to the chassis. The crossed beams 9210, 9220 thus form a scissor arrangement, and this is actuated by a pair of airbags 990 which are arranged to expand in a generally segmental form. These airbags are in contact with plates (not shown) attached between the scissor beams. Initially (i.e. in the collapsed state) the air bags 990 are deflated. Then, to raise the platform 900 the bags are inflated, causing the scissor to expand (i.e. the beams pivot, the rollers roll across the plate 970 and platform 900 surfaces). A further lifting force is provided by the central air bag/jack which is inflated at the same time.

Figure 72 shows the elevated scissor arrangement from the rear of the trailer. The opposing pairs of pivotally coupled beams 9210,9220 on either side of the trailer centre line can be seen, as can the plates 229, against which the air bags 990 exert a force to expand the scissor arrangement. Figure 73 shows the collapsed state, from the rear.

Although the above example employed pnexunatically actuated scissor lifts, it will be apparent that scissor lifts actuated by different means may be used in embodiments of the invention. For example, hydraulic actuators or screw mechanisms (screw jacks) may be used. With the pneumatic systems, it will be apparent that the trailer or vehicle may conveniently be provided with a compressor and a compressed air storage vessel for inflating the air bags / air j acks.

Figure 74 shows part of a vehicle embodying the invention, the vehicle including a well 4000 with a single load-canying platform 5 in it. The platfonn 5 can be moved up and down within the well by means of a scissor lift mechanism, broadly the same in operation to that described above with reference to figures 70-73. The mechanism comprises three scissor-jack assemblies 920a, 920b, 920c, spaced apart along the well's length. As can be seen from figure 74, in this example, two upper platform supports 11A and 1 IB are secured to the sidewalls, at two different predetermined heights. A rear support platform and horizontal drive can thus be operated to select the supports onto which the rear load carrying platform is placed. Figure 75 shows a cross section of the vehicle, along line A.- A from figure 74. Only part of one scissor mechanism is therefore shown. The crossed scissor members 9210, 9220 can be seen, anchored at one end to hinged supports 940, 950, and carrying rollers 960 at the other end. Thus, the platform 5 is hingedly coupled at one side to the scissor mechanisms, and at the other side is simply resting on the rollers 960. To facilitate maintenance, a hoist anchor point 500 is provided on the vehicle ceiling, above the side of the platform resting on the rollers. By suitable connection 510 the platform can simply be lifted, such that it rotates in the direction indicated by anow 520, thereby permitting access to the volume beneath it in the well (and hence facilitating maintenance and cleaning of the well and well-lift assembly). The supports 11 A and 1 IB are in the form of shelf members extending transversely into the vehicle cargo space from the side walls. The upper platform can be slid onto the shelves, or may comprise an array of rollers arranged to rest on and roll along the upper surfaces of the shelf supports HA and llB.

It will be appreciated that the scissor lift arrangement described above in relation to the rear platforms, or indeed aspects of it, may also be used in embodiments to act as the lifting mechanism for one of more platforms arranged in the vehicle well. Such an embodiment is illustrated in figures 76 to 81.

Referring to fig 76, the vehicle roof is denoted 1001. In the well region there are a plurality of transverse, structural (i.e. load-bearing ) partitions 402. Each has an upper load-bearing surface 403 that is level with the normal floor F of the vehicle interior. Between each pair of partitions is a respective well platform. 5a,5b,5c, and its conesponding scissor lift assembly 920a, b and c. Each scissor lift comprises crossed, hinged arms 9220, 9210, which are connected at one end either to the platform 5 or a support beam 970, and the other ends carry rollers 960. The pivots 930 of the scissor anangements are horizontal, extending along a longitudinal axis of the vehicle. Thus the scissors operate transversely. It should be noted that the scissor lifts are supported not by the well floor panel 401, which may have low strength, bnt by the longitudinal members 970, which are themselves supported by the partitions 402.

Fig 77 shows the crossed members 9220,9210 opened out by the airbags 990 to lift the platform 5. The beam 9210 is hinged to a support member 970 in the form of a rigid steel angle, spaced from the floor 401, and the lower end of the other member 9220 carries a roller which runs on a plate 971 which is rigidly attached to and supported by a pair of longitudinal angle members 970. The well base panel 401 is supported along its sides by rigid chassis members 281. The well sidewalls 280 also connect to these chassis members. Figure 78 shows the lift mechanism in the collapsed position, and fig 79 shows the independently controllable platforms all in their lowered positions.

Fig. 80 shows a transverse partition, comprising a lower beam portion 4021 which is supported only at its ends. The partition thus transmits loads to the chassis members, not to the centre of the panel 401. A.s shown in fig 81, ends of the partition beam 4021 sit on plates 4022 above the rigid angle members 2 81, the plates 4022 maintaining a separation 4023 between the partition and the panel 401. The partitions also carry the lift assemblies, and hence the well platform loads are transmitted to the sides of the well, permitting a low-strength, insulating panel 401 to be used for the well floor.

Claims

CLAIMS CLAIMS

1. A- vehicle comprising a load-canying well and at least one load-carrying platform which is vertically displaceable within the well to enable a payload to be lowered into the well, wherein the or each platform is mounted on support members carried by sidewalls of the well, and means are provided for moving the or each platform relative to the sidewalls on the support members.

2. A. vehicle according to claim 1, wherein the or each platform is suspended on a plurality of flexible support members.

3. A. vehicle according to claim 2, wherein each flexible support member extends downwards from a respective anchorage point mounted on a sidewall of the well.

4. A. vehicle according the claim 3, wherein the anchorage points are defined by sidewall plates which form inner walls of the well.

5. A. vehicle according to claim 4, wherein each anchorage point comprises a support plate secured to the sidewall plate, the flexible support member defining a loop extending around the support plate.

6. A. vehicle according to claim 5, wherein the position of each support plate on the respective sidewall plate is adjustable to adjust the effective length of the flexible support member looped over it.

7. A. vehicle according to any one of claims 2 to 6, wherein each flexible member is in the form of a strap.

8. A. vehicle according to any one of claims 3 to 7, wherein each flexible member is connected to means carried by the respective platform for drawing the flexible member into a space beneath the platform.

9. A vehicle according to claim 8, wherein each flexible member extends around a roller carried by the platform and is connected to a hydraulic actuator carried by the platform, the hydraulic actuator being extensible in a direction parallel to an upper surface of the platform.

10. A vehicle according to claim 9, wherein the hydraulic actuator is connected to a hydraulic fluid supply ounted on the well through an extendible piston and cylinder coupling one end of which is mounted on the platform and the other end of which is mounted on the well.

11. A vehicle according to any preceding claim, wherein the or each platform supports projections received within vertical guide tracks fitted to the well walls.

12. A vehicle according to claim 11, wherein means are provided for obstructing upper ends of the guide tracks to lock the or each platform in an elevated position.

13. A vehicle according to claim 2, wherein each flexible support member extends from a respective anchorage point on the platform and around at least one side wall - mounted pulley to an actuator located within the well.

14. A vehicle according to claim 13, wherein four anchorage points are distributed around the perimeter of the platform, each anchorage point being connected to a respective flexible support member in the form of a cable, all of the cables being guided by pulleys to a common actuator housed along one side of the well.

15. A vehicle according to claim 14, wherein the actuator supports a first pulley which is displaceable relative to the well, the cables extending from anchorage points in the well and around the first pulley.

16. A vehicle according to claim 15, wherein a first cable extends from the actuator, around a second pulley mounted in the said one side of the well above the actuator, around a third pulley mounted in the side of the well, and around, a fourth pulley mounted on a wall of the well above a first platform anchorage point to which the first cable is connected, a second cable extends from the actuator, around the second pulley, around a fifth pulley mounted in the side of the well platform, and around a sixth pulley mounted on a wall of the well above a second platform anchorage point to which the second cable is connected, a third cable extends from the actuator, around the second pulley, around a seventh pulley mounted on a wall of the well, and around an eighth pulley mounted on a wall of the well ab>ove a third platform anchorage point to which the third cable is connected, and a fourth cable extends from the actuator, around the second pulley, around a ninth pulley mounted on a wall of the well, and around a tenth pulley mounted on a wall of the well above a fourth platform anchorage point to which the fourtli cable is connected.

17. A vehicle according to claim 15, wherein a first cable extencLs from the actuator, around a second pulley mounted on the said one side of the well above the actuator, around a third pulley mounted in the well above the second pulley, and around a fourth pulley mounted in the well above a first platform anchorage point to which the first cable is connected, a second cable extends from the actuator, around the second pulley, around a fifth pulley mounted in the well above the second pulley, and around a sixth pulley mounted in the well above a second platform anchorage point to which the second cable is connected, a third cable extends from the actuator, around a seventh pulley mounted in the well, around an eighth pulley mounted on one side of the well and across the floor of the well beneath the platform to a ninth pulley mounted in the opposite side of the well, and from the ninth pulley aronnd a tenth pulley mounted in the well above a third platform, anchorage point to whi ch the third cable is connected, and a fourth cable extends from the actuator, around the second pulley, around an eleventh pulley mounted in the well, around a twelfth pulley mounted in one side of the well and across the floor of the well to a thirteenth pulley mounted in the opposite side of the well, and from the thirteenth pulley around a fourteenth pulley mounted in the well above a fourth platform anchorage point to which the fourth cable is connected.

18. A vehicle comprising a front section defining a load-canying front floor, a rear section defining a load-carrying rear floor, and a well section located between the front and rear sections, the well section including a thermally insulated well floor, thermally insulated transverse sidewalls extending downwards from the front and rear floors to the well floor, and thermally insulated longitudinal sidewalls extending between the well floor and the front and rear sections, wherein at least an upper portion of each longitudinal sidewall comprises inner and outer load-hearing sheet members separated by an insulating layer, the sheet members being fixed to the insulating layer to define a load-bearing laminated beam extending between the front and rear sections.

19. A vehicle according to claim 18, wherein each longitudinal sidewall includes a rectangular outer frame formed from sheet members, at least an upper part of the frame being fixed to the insulating layer.

20. A vehicle according to claim 18 or 19, wherein the sheet members are secured by screws driven into the insulating layer, the screws on opposite sides of the insulating layer being offset relative to each other to ensure their separation by material fonning the insulating layer.

21. A vehicle according to claim 18, 19 or 20, wherein the insulating layer includes a layer of polycarbonate.

22. A vehicle according to any one of claims 17 to 21, wherein the front and rear sections comprise longitudinally extending frame beams connected to transverse frame beams, the transverse frame beams being secured to the transverse sidewalls of the well section.

23. A vehicle according to claim 22, wherein the transverse frame beams are connected to an inner transverse wall of the well by thermally insulating connectors.

24. A vehicle according to claim 23, wherein each connector is defined by spaced apart plates extending from the transverse frame beam and the well wall, the plates being interconnected by a bolt passing through the apertured plates, and the bolt being thermally insulated from the plates.

25. A vehicle comprising a first section defining a load-canying front floor, a rear section defining a rear floor, a well section located between the front and rear sections, and means for lowering payload into the well section, wherein a support platform is vertically displaceable above the rear floor between raised and lowered positions, and the support platform carries a load-canying platform which is horizontally displaceable over the well when the support platform is in the raised position, the load-canying platform being displaceable from the support platform onto supports mounted on sidewalls of the vehicle.

26. A vehicle according to claim 25, wherein rollers are interposed between the support platform and load-carrying platform, and between the sidewall supports and the load-canying platform.

27. A vehicle according to claim 26, wherein the load-canying pla-tform supports rollers along its longitudinal edges which run on tracks extending along longitudinal edges of the support platform.

28. A vehicle according to claim 26 or 27, wherein the sidewall svxpports include rollers on which formations on the longitudinal edges of the load-carrying platform roll.

29. A vehicle according to claim 28, wherein the sidewall support rollers are mounted on plates defining inner sidewalls of the well section.

30. A vehicle according to any one of claims 26 to 29, wherein the support platform carries a drive motor for displacing the load-carrying platform over the well.

31. A vehicle according to claim 30, wherein the drive motor drives a roller which rotates about an axis transverse to the vehicle, which projects above an upper surface of the support platform, and which frictionally engages a surface defined by the load- canying platform such that rotation of the roller drives the load-canying platfonn relative to the support platform.

32. A vehicle comprising a load-canying well, at least one load-carrying platform which is displaceable within the well to enable a payload to be lowered into the well, and lifting means operable to raise and lower the platform within the well, the lifting means comprising at least one scissor lift.

33. A vehicle in accordance with claim 32, wherein the scissor lift comprises at least one pair of crossed support members, pivotally connected together, and actuator means operable to control the relative angular orientation of the crossed support members, the support members being coupled to the platform and to the well such that as their angular separation is increased by the actuator means the platform is driven upwards.

34. A vehicle in accordance with claim 33, wherein the platform is hingedly coupled to a first one of the pair of support members and is ananged to rest on a second one of the pair of support members, such that the platfonn can be lifted from the second support member to permit access to the lifting means beneath the platform.

35. A vehicle in accordance with any one of claims 32 to 34, wherein the lifting means is ananged to maintain the platform substantially horizontal as the platform is raised or lowered.

36. A vehicle in accordance with any one of claims 32 to 35, wherein the lifting means is carried, at least partially, by sidewalls of the well.

37. A vehicle in accordance with claim 36, wherein said sidewalls are longitudinal sidewalls of the well.

38. A. vehicle in accordance with any one of claims 32 to 37, comprising a transverse beam ananged forward of the platform and a transverse beam ananged rearward of the platform, the transverse beams extending from one well sidewall to the opposite well sidewall, the transverse beams supporting at least one longitudinal support member, the lifting means being supported by the at least one longitudinal support member.

39. . vehicle in accordance with claim 38, wherein end portions of the transverse beams are arranged to be supported proximate the sidewalls, and central portions of the transverse beams are not directly supported.

40. A. vehicle in accordance with claim 38 or claim 39, wherein each tranverse beam is part of a respective transverse partition in the well.

41. A. vehicle in accordance with any one of claims 32 to 40, comprising at least two said platforms, each having associated with it a respective lifting means, the platforms being spaced apart longitudinally in the well by a transverse partition.

42. A. vehicle in accordance with claim 41, wherein the transverse partition extends across the well, from one sidewall to the opposite sidewall.

43. A. vehicle in accordance with claim 42, wherein the transverse partition is connected to the sidewalls such that at least a portion of any vertical load applied to the transverse partition is transmitted to the sidewalls.

43. A. vehicle in accordance with claim 42, wherein the transverse partition comprises a load-bearing upper surface ananged to be substantially level with a floor of the vehicle adjacent the well.

44. A. vehicle in accordance with any one of claims 41 to 43, comprising a plurality of said transverse partitions spaced apart longitudinally in said well, a respective platform being ananged between each pair of adjacent partitions, and tbxe lifting means associated with each platform being supported by the respective pair of transverse partitions.

45. A vehicle in accordance with claim 44, wherein each transverse partition is supported by sidewalls of the well.

46. A vehicle in accordance with claim 1 , wherein the or each platform is mounted on a respective scissor lift, the scissor lift being supported, at least partially, by the well sidewalls.

47. A vehicle in accordance with any one of claims 32 to 46, comprising a pneumatic actuator arranged to drive the scissor lift.

48. A vehicle in accordance with claims 47, wherein the pneumatic actuator comprises at least one expandable air bag.

49. A vehicle in accordance with claim 1, wherein said support menxbers comprise at least a first pair of crossed support members, connected by a pivot, the means for moving the platform comprising actuator means arranged to provide relative rotation of the crossed support members about the pivot, the crossed support members being coupled to the platform and to sidewalls of the well such that said rotation results in a vertical movement of the platform.

50. A vehicle substantially as hereinbefore described with reference to the accompanying drawings.