NZ234393A

NZ234393A - Mobile collapsible gantry for lifting containers

Info

Publication number: NZ234393A
Application number: NZ23439390A
Authority: NZ
Inventors: Vail Martin John Hubner
Original assignee: Vail Martin John Hubner
Priority date: 1990-07-06
Filing date: 1990-07-06
Publication date: 1994-07-26

Description

<div class="application article clearfix" id="description"> 234 393 23 6 0 92^3 7 5 0 PATENTS FORM NO. 5 Fee No. 4: $200.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional NQL 234393/ 236092/ 237501 j Dated: 6 July 1990 /15 Nov 1990 /19 Mar 1991 "LIFTING DEVICE" I, Vail Martin John Hubner, a New Zealand citizen of 78 Valley Road, Mount Maunganui, New Zealand hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed to be particularly described in and by the following statement: 1 a t ? 34 3 9 3 236092237501 This invention relates to a lifting device. More specifically, this invention is directed towards lifting devices which may be collapsed or folded into a more compact form for transport, storage etc. Most applications of the present inventions will be directed towards, 5 though not restricted to, the road and rail transport sectors. A variety of lifting devices are known for use with road and rail transport. These range from large conventional type cranes and gantries. Some lifting devices are adapted for transport by the carrying truck and these range from the commercially known 'PALFINGER'™ which normally 10 comprises a lifting arm mounted to the rear deck of the truck, typically immediately behind the cab. However, such a device relies on the truck for stability, is based on a linked arm section and as a result has a limited load carrying capability. They are typically used in conjunction with small skips or bins filled with waste material. 15 More sophisticated and heavier duty apparatus are known and are —I disclosed in New Zealand patent specifications 198219, 152730 and 182563, for example. However there are disadvantages associated with the lifting devices disclosed in each of these specifications. For example, with the exception of 182563, the vehicle carrying the lifting device is unable to carry 20 a load unless perhaps a separate trailer is attached. This effectively means that the vehicle in question must be moved to the particular site in question. While this may not be a disadvantage where a load to be lifted is at the other end of the depot, problems become apparent when it is desired to use the lifting device at a remote construction site or a railway siding. 2 234393 23 6 0 92/23 7 5 0 1 The device of specification 182563 is adapted to tip a load during the lifting procedure and therefore is not generally suitable for lifting or transferring loads between vehicles. It is apparent that, from the referenced prior art, and available 5 machinery, there is an absence on the market and in the field for a device capable of lifting a reasonably substantial load and which may also be compacted or adapted into a compact form for transport. It would be even more desirable if the lifting device could also be carried by the vehicle carrying the load. Further, if it could be readily transferred between 10 vehicles, then it may even be more desirable to certain users. It is an object of the present invention to address the foregoing problems and disadvantages or at least to provide the public with a useful choice. According to one aspect of the present invention there is provided a collapsible straddle lifter comprising: 15 - a collapsible main beam assembly having a main load-bearing portion; at least two collapsible leg sets, of which there is at least one positioned; near each end of either an erected said main beam assembly or 20 main load-bearing portion thereof, and near the center of a collapsed said main beam assembly; a lifting assembly coupled to said main beam assembly. According to another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein said 25 main beam assembly is erectable into more than one configuration which have differing spans. 3 23 6 0 92 234393 237501 According to yet another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein an erected main beam comprises a load-bearing portion and a cantilevered portion of a lesser load bearing capacity. 5 According to yet another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein the legs of a leg set are capable of raising said main beam. According to yet another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein a leg set 10 may travel longitudinally with respect to said main beam assembly. According to yet another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein said lifting assembly is capable of raising, or assisting in raising the main beam assembly. 15 According to yet another aspect of the present invention there is provided a collapsible straddle lifter substantially as described above wherein the lifting device is capable of travel longitudinally with respect to said main beam assembly. The term 'collapsible' when used within this specification, shall denote 20 that a device, article or component which is so collapsible, is capable of being dismantled or disassembled, folded, contracted (as opposed to extended) and/or otherwise made to occupy a more compact form. Typically the process or procedure is reversible so that said device, article or component can be re-extended into one or more non-collapsed states. It 4 • ' 734393 23 0 0 92)23 7 5 0 1 is also envisaged that a device, article or component may be collapsible into one or more semi- or fully collapsed states. The type of lifting device to which this invention is directed is sometimes referred to as a straddle lifter. This name is derived because the lifting 5 device typically straddles the load upon which it operates. It is common for these types of lifters to comprise a central lifting platform or beam and one or more leg sets of which two are generally positioned near the outer ends of said platform or beam. A gantry falls within the general definition of straddle lifter. However, the present invention, while falling within the 10 definition of straddle lifter, differs from known straddle lifters, which differences will become apparent from the description of the present invention contained herein. The main beam of the present invention, as in most other types of straddle lifters, forms the backbone of the lifting device. The main beam is typically 15 load bearing or according to different types of constructions, may comprise a separate or definable load bearing section. Thus, for example, only a particular section or portion of a main beam may be load bearing. The main beam may comprise many different forms and configurations. Similarly it may comprise a single beam or more commonly will comprise 20 several different components. These components may infer different qualities to different sections of the beam. As it is possible in many embodiments of the present invention, for various components to travel along the main beam (for instance, the lifting assembly and perhaps the leg sets), the main beam may include rails or 25 guides for any travelling or moving components. These may be combined with various reinforcing members or components specifically adapted to 5 ?34 393 23 6 0 92b3 75 0 perform certain functions. As aforesaid, there are many different configurations and constructions that a main beam may take. General engineering principles should be applied to same and it is envisaged that the construction and design of a main beam to perform certain functions 5 and conform to certain characteristics would be within the skill or knowledge of a skilled addressee of the art. Referring once again to the load bearing section, this is typically a section of (or the entire) main beam which is capable of supporting a lifted load. The load which is capable of being supported by this section need not be 10 constant along it entire length. For instance, in embodiments where sections of the main beam and load bearing section extend outwardly of any supporting leg sets, the load able to be carried on such cantilevered sections of beam may be less than for the section of beam bridging the legs (typically the load-bearing portion). The maximum load may rapidly fall 15 off as the distance into the cantilevered section is increased. As another example, in a particular embodiment of the present invention to be described in detail later, the main beam is able to be assembled into two lengths. In one form the beam is able to support a substantially greater load than when in its other assembled configuration. 20 As many embodiments of the present invention are adapted to be collapsible into a form suitable for storage or ready transport, it is common for the main beam of many embodiments to be collapsible. There are many different arrangements by which this can be effected. For instance, '' certain portions or sections of the main beam and various associated 25 components can be made to telescope one within the other. Alternatively, joints and seams may be provided to allow various parts to fold or pivot with respect to one another. 6 234393 23 6 0 92^3 7 5 0 I In other embodiments, certain components and section may be able to be disassembled. Provision may be made for disassembled sections to attach or otherwise interact with each other in a form convenient for storage, transport etc. It is also envisaged that many other techniques that allow 5 collapse of the main beam and components associated therewith, may be employed - i.e. other than the foregoing methods or combinations thereof. Due to the importance of the main beam as the major load carrying component of the device, consideration to the nature of the folding may be required. It may for instance be desirable to provide additional reinforcing 10 in the vicinity of any joints or folds etc. Pins or locking devices may be used to help maintain the various components in relation to each other. Swinging, locking arms are another viable option. Preferably, any such sections which are locked should also be strengthened. Another method would be to provide sections of panel, channel or encasing members which 15 slide or position over any weak or susceptible areas and effectively 'splint' the area in question. Many other techniques are possible and once again it is envisaged that a skilled addressee of the art would be able to recognise any such considerations requiring attention during the design, construction and operation of a lifting device according to the present 20 invention. Some consideration must also be given to the means by which the main beam assembly is to be erected or collapsed. While this may be performed manually, the size and weight of various components may require some form of assistance, such as a power means. How any such assistance is to 25 be provided will be dependant upon the method of collapse and erection of the device. For an embodiment which uses folding sections it may be satisfactory to utilise some form of gearing or lever arrangement. In a 7 ' ' 234 393 23 6 0 9 ^23 7 5 0 1 preferred embodiment to be described later, use. is made of a cable and pulley system to aid erection of the main beam assembly. Many other methods may be chosen and these few examples are by way of example only. 5 Some form of power or drive means may also be provided to assist the operator. These may include hydraulic rams, various rotating motors, pneumatic systems or any other means which may be adapted for use with the invention. Further, these may be powered by their own source or may rely on energy or fuel provided by a separate vehicle. For instance, a 10 pneumatic system could operate on the compressed air system common to many large trucks or rigs. The legs comprise the main supporting structure for the lifting device. Typically the legs are organised into leg sets, for stability. Each leg set will often comprise two or more individual legs. However, it is possible that 15 some leg sets may comprise only one leg - the actual number of leg sets and legs provided will depend on their arrangement. The overriding consideration in most situations is that of stability of the lifting device, both at rest and when lifting a load. With this in mind, it is common for many embodiments of the present invention to comprise several leg sets which 20 each comprise two or more legs which erect into a splayed arrangement or for there to be embodiments in which there is a overall splayed arrangement of leg sets. This helps increase the effective ground contact area so that the centre of mass will virtually always fall within this area and make tipping of the lifting device (especially when carrying a load) 25 unlikely. As it is desirable for the centre of mass of the system to fall within this ground contact area during any conceivable operation of the lifting device, 8 234393 236092237501 it is commonly desirable that at least two leg sets are positioned one near each end of the load bearing portion of the main beam assembly. This often means they are positioned slightly inwardly of the ends of the main beam assembly, though it is desirable in cantilevered embodiments that 5 they are not inwardly so far that a load on the cantilevered section (if such travel is permitted) of the main beam will tip the lifting device. The description of the position of the leg sets with respect to the main beam assembly may be further refined insofar that the leg sets are positioned substantially near the outer ends of the load bearing section of the main 10 beam. Thus for a main beam assembly which may comprise one or more assembled states, the actual leg sets may not necessarily be near the outermost edges of the main beam. As it is common for the main beam, in many embodiments, to be collapsible, it is often not possible for the leg sets to remain near the outer 15 perimeter of the main beam or load bearing section when the device is collapsed. Thus it may be necessary for the leg sets to be separable from the main beam assembly or else be capable of longitudinal travel with respect to the main-beam assembly. In this latter method (which is used in a preferred embodiment to be described later) the section of leg set 20 which is coupled to the main beam assembly may comprise a carriage or pseudo-carriage. There may be a sliding arrangement with respect to the main beam which allows the leg sets to slide or otherwise travel along the main beam assembly - this motion may be assisted by rollers or wheels. Pins or various locking mechanisms may be provided to maintain leg sets 25 in a desired position with respect to the main beam assembly. Motive means (for instance rams, geared arrangements or sheath/pulley arrangements) may also be provided to assist travel of the components 9 234 393 23609 22 375 though the mechanism may also rely on manual labour or may provide assistance (e.g. gears, levers, pulleys etc) to assist an operator. Other embodiments may rely upon the leg sets being able to be disconnected from the main beam assembly and re-positioned for storage 5 or carriage. Again various methods and locking devices may be used to assist with disassembly or erection. Further comments may be made that for a very short main beam assembly, or an embodiment which relies on short cantilevered sections outside of the leg sets, it may not be necessary to re-position the leg sets 10 (with respect to the main beam) from a preferred assembled state to a disassembled state. In some embodiments, it may be possible to splay the legs outwardly so as to clear the sides of any vehicle straddled by the assembled device and thus once again the leg sets may remain in a single position with respect to the main beam (for assembled or disassembled 15 states). In embodiments where the leg sets are re-positioned during disassembly, they may be removed entirely from the main beam assembly or be positioned thereon. Typically this will be in a relatively centralised position though will depend upon the method of collapse of the lifting device. 20 As mentioned above, each leg set will comprise one or more legs though preferably two or more in a splayed arrangement. For such splayed legs, various means either manual or mechanical (and possibly including power assistance) may be incorporated to effect the spreading thereof. Some of these means may also serve to maintain the legs in a particular 25 splayed position. However simpler techniques, such as a line interconnecting (and restricting the maximum spread of) the legs could also be used. 10 2.34 393 23 6 0 9 2j?3 75 0 As the height of the assembled lifting device must be greater than the height of any deck or load carrying platform that it straddles, it is common for the legs to be extendible. Many methods may be adopted. For instance, those which may be employed with the main beam assembly, can also be 5 used with respect to the legs to effect collapse and assembly. Often, each leg will either telescope or fold, as will be apparent in the preferred embodiments to be described later. Consideration must also be given to how the legs are to be extended. As the main beam assembly is generally stored or carried in a lower position 10 than it would attain during assembly of the lifter, it may be necessary for the legs, as they are extended or erected, to lift the main beam assembly to its 'erected' height. Various labour intensive or mechanical means may be used to raise the main beam assembly and any associated components during the erection of the legs. Again, any known mechanical or power 15 driving means may be used, such as methods similar to those associated with the erection and collapse of other components of the lifting device (e.g. screws, hydraulics, pneumatics). Even a separate lifting arm may be used to help raise the device. In some versions the legs may be used to raise and lower the main beam assembly and load. 20 In other embodiments (for instance the preferred embodiment to be described later within this specification) the main beam assembly is raised into its ultimate height (for an assembled lifter) by the lifting assembly thereon. The legs are able to be assembled by allowing them to unfold or drop until they contact the ground. Such embodiments simplify the 25 construction of the overall lifting device as separate lifting means for each leg (or a majority of the legs) are not required - the consideration being the choice of a lifting assembly which is able to raise the main beam during 11 234393 23 6 0 92(23 7 5 0 1 assembly or collapse. In other embodiments, means separate from the actual straddle lifter may be provided or required to help raise the main beam assembly to the correct height. According to the method of collapse of the legs, various means may be 5 provided to maintain them in the correct or desired height. This may comprise any number of locking means, such as pins, sliding channels or collars and so on. Provision may be made also to lock the legs into one of several extended lengths. This feature may be useful when the straddle lifter is used on ground which is not level or has surface irregularities. 10 Further modification may also be made to cater for any such irregularities in the ground support. One method involves the manner of connection of the leg sets to the main beam assembly. The main beam could be coupled to the leg set by a pivotable connection, such as an omni-directional mount (e.g. a gimbal or ball-joint arrangement) or connection about a single 15 rotational axis substantially longitudinal to the main beam assembly. Here, a certain degree of independence between individual leg sets may attained which will cater for the instance that the slope of the ground upon which each leg set rests may not be equivalent. Provision may be made to lock the leg set in position with respect to the main beam assembly once 20 the assembled straddle lifter has been placed or settled into a stable position. This will help prevent a load being lifted acting as a pendulum i.e. able to rock backwards and forwards if the weight distribution is not even. This may or may not be a desirable feature, and could conceivably be incorporated as a special feature of some embodiments. 25 Feet may also be provided at the base of a leg; these may be dismountable or foldable for collapse of the invention. Further, provision may be made within the feet or each foot assembly to cater for irregularities in ground 12 ' ' 234393 23609^37501 surfaces. Each foot assembly may comprise a pad or a miniature tripod to cater for surface irregularities. Many different configurations may be adopted. A pivotable union between a foot and leg may also be employed. As a further comment on the splayed nature of legs of each leg set: In the 5 preferred embodiments described later, there are two leg sets each with two splayed legs. Each set of two splayed legs is splayed within a plane substantially perpendicular to the longitudinal axis of the main beam assembly. Each set of splayed legs is substantially parallel to the other i.e. the planes in which they exist are substantially parallel. The overall 10 appearance is substantially that of a common, child's swing. The base area defined by the contact point of each foot is substantially a rectangle. Legs sets comprising higher number of legs may be splayed in three dimensions. For instance, a leg set comprising three legs may have them splayed in the manner of a tripod or trivet. Many different arrangements 15 and configurations are possible for various leg sets. It is also noted that additional leg sets may be provided to help support a main beam assembly and perhaps increase maximum loads supportable by same. Such leg sets may be connected at various points along the main beam assembly, preferably near the central sections. However 20 consideration needs to be given that they do not interfere with the lifting and travel of any load or movement of vehicles beneath the lifter. In this respect, any leg sets may be positioned to extend into the space between adjacent vehicles (for a straddle lifter which spans two or more vehicles). Further, legs of the leg set may extend forwardly or behind the main beam 25 assembly, so as also not to interfere with any load being transported. Such additional leg sets may also be optional and may not be extended or attached in all operations of the device. 13 234393 236092h37501 Also provided on the straddle lifter is at least one lifting assembly. Essentially each lifting device is that part of the device which is used for coupling a load to the main beam assembly. It may be capable of lifting and lowering a load itself, which is true for most embodiments. However 5 in embodiments where the entire beam assembly is raised or lowered by legs to effect load movement, no such provision (for raising the load) may be incorporated into the lifting assembly. In such an embodiment a load is fixed to the load bearing assembly which is then raised or lowered to effect a corresponding lifting or lowering of the 10 load. In this modification, the required vertical translation of the load bearing section is achieved via the legs. Each leg or combined leg set will need to be extendible/retractable to that its length, and thus height, can be altered. The load bearing section which is attached near the top of each leg will also vary in elevation as the leg height alters. 15 A variety of means may be used to power the extension and retraction of each leg. Typically a screw device, such as used in the lifting assembly to be described, may be used. However it may be more practical to use a hydraulic ram, chain and pulley system (or the equivalent) or any other means commonly used for lowering or raising loads. 20 Each leg may function independently though it is perhaps preferably that some interdependence is involved to allow the lifting of the load bearing section to be performed evenly (i.e. without tilting or unbalancing the apparatus). Such interdependence may range from allowing legs to act in unison (either as leg sets or altogether) to a levelling control which 25 maintains the load bearing section in a horizontal (or other) position even though the straddle lifter may be on uneven ground. 14 234393 23 6 0 92(23 7 5 0 In such modified embodiments it may be desirable to provide a lifting assembly on the load bearing section which is capable of horizontal travel thereon (for performing horizontal load shifts). For simplicity, only embodiments with one lifting assembly will be 5 described - the principles may be extended to straddle lifters with multiple lifting units. Lifting assemblies for use with the present invention may be further broadly categorised into two main areas: i) Those capable of longitudinal travel with respect to the main beam assembly, and 10 ii) Those fixed with regard to longitudinal travel along the main beam assembly. For those fixed types typically capable of only vertical movement of a load, it is envisaged that they will be used primarily on narrow straddle lifter embodiments. By this, are intended embodiments which span 15 substantially only a single vehicle and wherein the movement of loads is achieved by lifting a load off the deck of a vehicle, substituting another vehicle in its place and re-lowering the load. Alternatively, the load may be picked up off, or lowered on to the ground. It is recognised that this particular form of load movement is time consuming and labour intensive 20 as it requires frequent moving of vehicles with respect to the straddle lifter. This may not represent a problem in situations where there are a relatively few number of load movements and where the convenience of being able to lift a relatively heavy load is of importance. The problem may also be partially alleviated wherein the straddle lifter is adapted to be 25 readily moved, such as where wheels are provided on the legs. Because of the smaller size of these generally narrower embodiments of a straddle 15 2 3 4 3 9 3 23 6 0 92^3 7 5 lifter, they are often of a more simple construction and fold to a more compact form. This may represent an advantage. It is envisaged however, that fixed non-travelling lifting assemblies need not be restricted to these 'narrow' type embodiments. They may be 5 employed if the need exists in many embodiments of a straddle lifter. The travelling type lifting assembly finds greater use in 'wider' embodiments of a straddle lifter. However, travelling assemblies may also find use on narrower embodiments of a straddle lifter. Here (in these latter types), it is envisaged that in most cases travel will be of a limited 10 nature to allow for minor lateral adjustment of the load onto a vehicle. This may be especially important where connection points on the load must correspond with complementary connectors on the vehicle. In other embodiments which have a greater degree of travel, it is envisaged that it will be possible to horizontally transport loads between 15 two adjacent vehicles. The preferred embodiment, to be described later, is an excellent example of the two principles. The embodiment which may be constructed in a narrow form, allows limited horizontal travel of the lifting assembly to allow for minor adjustments in placing the load on a vehicle. When the embodiment is constructed according to its wider form, 20 it is possible to transport loads between two adjacent vehicles which the lifter straddles. The lifting assembly may couple to the main beam via a carriage interacting with rails or guide on the main beam assembly. Typically the portion of the main beam with which the lifting assembly interacts, is the 25 load bearing section. Numerous methods may be employed to enable 16 234393 * 236092237501 ;horizontal travel of the lifting assembly along the longitudinal axis of the main beam. ;Another option is to provide limited forward and rearward travel of a load i.e. substantially perpendicular to the main beam longitudinal axis. This 5 movement will often be used primarily for aligning connectors and fasteners between load and vehicle. ;Also associated with the lifting assembly, is means for raising or lowering a load. This may employ many different forms. Perhaps a simplest embodiment is wherein the lifting assembly comprises a hook on a chain 10 which may be raised and lowered. In other embodiments, different forms of connection may be provided, such as extending arms. These arms may have pivotable joints or may telescope. Many other possibilities are envisaged and may be used. ;Also a consideration is that it may be desirable for the lifting arms (or 15 whatever other form is provided) to be able to apply a downward force other than just an upward lifting force to counteract the weight of the load. ;Being able to provide such a downward force enables the main beam to be lifted from the truck during assembly of the lifting device. This has already been described earlier, and will be described once again during the 20 description of the detailed embodiment of a detailed embodiment of the invention. No further mention will be made at this point other than to say that some forms of lifting means are more suited for this purpose than others - these will be apparent to a skilled addressee of the art. ;Means to drive a lifting assembly may come from several sources. In a 25 simplest embodiment, the entire lifting assembly may be manually driven. ;In such a case, it is desirable, if not essential, that a system of gears, ;17 ;234393 ;236092237501 ;pulleys or other methods are employed to aid the manual operator. However, most embodiments will employ some form of power assisting means. This may comprise a motor housed on the straddle lifter or any form of motor or power producing device if adapted accordingly. ;5 Alternatively, power or power systems may come from another vehicle e.g. the electrical or compressed air output or a truck or rig. It is also noted that devices of relatively small power output may be used providing suitable gearing is provided. It is assumed that these considerations would be readily apparent to skilled addressee of the art. ;10 Many modifications may also be made to the straddle lifter as a whole, though some of these modifications relate to individual components while others involve the inter-relationship of various components thereon. ;One modification is provision for the straddle lifter to be moved when it is in an erect state. Most simply this will include the provision of wheels, 15 tracks or skids on at least several of the legs of the lifter. There may be means provided by which these wheels can be raised off the ground during such operations as lifting a load. Any wheels or tracks so provided may also be driven. The nature of any motive means therefor, as well as the wheels or tracks themselves, will be influenced by factors such as whether 20 it is desirable to be able to move the straddle lifter whilst a load is being carried. Other considerations may include whether the straddle lifter is able to be turned. As it is typical for many embodiments (such as where lateral movement is most required) to incorporate a travelling lifting assembly, there is generally no need for the straddle lifter to be able to 25 travel in any direction other than substantially perpendicular to the longitudinal axis of the main beam. However, if desired, steering may be ;18 ;234393 ;23 6 0 9^3 7 5 0 ;incorporated, even if only restricted to the manner in which tracked vehicles such as a bulldozer turn (i.e. one side remains stationary). ;Many components may also interact or inter-relate on assembly of the lifter. For instance, the motive means for driving one component may also 5 be used to drive others. There may be some form of connection or release to vary the position to which the output of the motive means (whether the motive means be the human operator or a motor etc) is directed and to achieve the required consequence. In a preferred embodiment, a system of cables, pulleys and hydraulic rams are able to alternate between functions 10 such as unfolding the main beam, moving the leg sets outwardly during assembly and causing horizontal travel of the lifting assembly during operation of the straddle lifter. This is but one example and many possible variations in which various components can inter-relate with others are possible. ;15 As another example, it has been mentioned that the lifting device may be used to help raise the main beam during assembly of the device. As one step further, if the lifting assembly is able to travel horizontally with respect to the main beam, then by fixing the lifting assembly to the truck during assembly, and causing the lifting assembly to move in relation to 20 the main beam, the main beam is able to be extended in a direction either side of the truck. While some stabilization of the truck may be required, ;this process is useful for wider embodiments of a straddle lifter which must straddle an adjacent vehicle. Typically this process is performed before the legs of the straddle lifter are extended to contact the ground. 25 Many variations of this process may occur though one specific method will be described in the description of a preferred embodiment of the invention. ;19 ;234393 ;• 23 6 0 9 2| 3 7 5 0 ;If the collapsed straddle lifter is to be carried by a vehicle, then some modification may need to be made to that vehicle. For embodiments, such as described above, where the beam is extended to either side of the vehicle, ;some form of stabilization may be required such as arms on the truck. ;5 These may comprise simple props or in a more sophisticated embodiment, ;comprise the hydraulic feet common on many trucks carrying cranes. ;An area is usually provided for storage and carriage of the lifting device. ;This may be immediately behind the cab so as to allow the container or load to be accessed from the sides or rear of the vehicle by conventional 10 means such as forklifts. However, the lifting device may equally well be stored in another point on the truck. ;It may also be desirable to provide some form of cage or connections for securing the lifting device. This will depend on the nature of the collapsed straddle lifter. ;15 As a further option, the straddle lifter may occupy a space typically reserved for a load. Modification of the legs, feet or other components to connect to load fastening points on the load carrying deck (e.g. the 'Twistlock' system) may be provided, s ;Materials for the construction of the straddle lifter should be in accordance 20 with standard engineering techniques. Most typically steel will be used as the major material of construction, this being preferably galvanised or protected or coated in some manner. ;20 ;234393 ;23609^3750 ;Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of reference only and with reference to the accompanying diagrams in which: ;Figures 1-8, unless otherwise stated, are those accompanying Provisional 5 Specification No. 236092. ;Figures 1-2: of the provisional specification for 236092 are sequences of diagrams illustrating the unfolding and erection of two possible embodiments of the present invention, ;Figure 3a-c: are a series of diagrams illustrating the unfolding of the 10 main beam of a further preferred embodiment of the present invention, ;Figure 4: is a diagrammatic perspective view of the preferred embodiment of Figures 3 in a 'narrow' assembled state, ;Figure 5: is a perspective diagrammatic view of the embodiment of 15 Figures 3 and 4 assembled in a 'wide' state, ;Figure 6: is a diagrammatic perspective view of the device folded and stowed on the rear of a truck, ;Figure 7: is a perspective diagrammatic view of the main beam being extended to one side of a carrying truck during assembly of 20 the straddle lifter, ;Figure 8: is a diagrammatic cross-sectional view along the embodiment of a main beam of Figures 3, looking in a longitudinal direction, ;21 ;10 ;15 ;Figure 9: ;5 Figure 10: ;Figure 11: ;Figure 12: ;Figure 13: ;Figure 14: ;Figure 15: ;20 Figure 16: ;Figure 17: ;23 6 0 92 ;234393 ;23 7 5 0 ;is a perspective diagrammatic view of a further preferred embodiment of the present invention adapted to couple to the twist lock fasteners on the deck of the vehicle, such as a truck; shown in a folded and stored state, ;is the embodiment of Figure 9 where the main beam assembly is partially unfolded, ;is the embodiments of Figures 9 and 10 wherein the main beam assembly is assembled in a narrow state, ;is the embodiment of Figures 9-11 wherein the leg sets have travelled outwardly to the ends of the narrow-form main beam assembly, ;is the embodiment of Figures 9-12, assembled and lifting a load from the platform of a truck, ;is the embodiment of Figures 9-13 positioned over a railway line and used in an operation for the transfer of a container from the deck of a truck to the deck of a railway wagon, ;is essentially the embodiment of Figures 9-14 when stored in a folded state on the platform of a railway wagon rather than a truck, ;is the embodiment of Figure 15 where the main beam assembly is in a semi-assembled position, ;is the embodiment of Figures 15 and 16 with the main beam assembly being further unfolded for use in a wide-form, ;22 ;2.34393 ;# ;10 ;15 ;20 ;23609 2j? 37501 ;Figure 18: ;25 ;is the embodiment of Figures 15-17 where the main beam assembly is fully assembled into a wide form, ;Figure 19: is the embodiments of Figures 15-18 wherein the leg sets have travelled to the ends of the wide-form main beam assembly, ;Figure 20: is the embodiments of Figures 15-19 where the wide-form straddle lifter is being used to transport a load between side by side adjacent truck and railway decks, ;Figure 21: is a close-up top perspective view of detail of the top of the leg set and main beam assembly of the embodiments of Figures 9-20, and ;Figure 22: is a close-up bottom perspective view of the top portion of the leg set and main beam assembly of the embodiments of Figures 9-20. ;With reference to the diagrams and by way of example only there is provided a collapsible lifting device, generally indicated by arrow 30, having one or more load carrying assembled states (refer Figures 4, 5) comprising: ;a main beam, generally indicated by arrow 31 having a load bearing section; ;two or more collapsible leg sets 17 which are positioned near each end of the load bearing section of the main beam 31 when said lifting device 30 is in a load carrying assembled state (e.g. Figures 4 or 5); a lifting assembly, generally indicated by arrow 32, coupled to said main beam 31. ;23 ;234393 ;• 23609 2j2 3750 ;Figure 3a illustrates the main beam 31 in a folded state. Figures 3b and 3c illustrate the gradual unfolding of the main beam assembly 31 from a 'U'-shaped into a substantially linear member. This principle may be extrapolated to enable further folding of the main beam assembly into a 5 rectangular cuboid configuration. ;The unfolding is effected by the operation of four hydraulic rams 4 in conjunction with wire cable 2 and sheaves or capstans 33-35, as will become apparent. The wire cable 2 is fastened at each end to a sliding carriage 3. The cable extends round the outer 33 and intermediary 34 10 sheaves and totally encircles the central sheaves 35. If all these sheaves were fixed into position, then the length of cable 2 required in the folded position would be greater than for the unfolded linear main beam as illustrated in Figure 3c. To accommodate this difference in cable length, the central sheaves 35 are movable apart from each other. These sheaves 15 are spaced apart by a greater distance in the linear main beam 31 (refer Figure 3c) than in the folded form (refer Figure 3a). The greater distance by which the wire cable 2 must be to encircle the spaced apart sheaves 35, accommodates any possible slack in the rope. ;To convert the main beam 31 from a folded form into the linear assembled 20 state, the rams 4 apply pressure on the central sheaves to space them apart. This in turn places tensions on the wire cable 2 causing the main beam assembly 31 to straighten to alleviate the tension. It is noted that additional means may be provided to help promote unfolding of the main beam assembly; this may comprise the addition of an auxiliary ram or 25 motor and gear arrangement. ;24 ;• 2 3 6 0 9 2 ;234393 ;23 7 5 0 ;The main beam assembly 31 comprises two major beams or rails which are parallel and spaced apart. The view of Figures 3 is a cross-sectional view looking from the center of the main beam assembly. As this is also essentially a plane of symmetry, the view may be looking either forwardly 5 or rearwardly of the assembly 31. ;The sheaves 33-35 are thus placed between the two major beam or rail sections 36. Reinforcing members 10 between the beams 36 space and hold them apart. ;The main beam assembly 31 is divided into five sections of which some are 10 equivalent. There is one central section 37. Either side of this is an intermediate section 38 and to the outside of these are an outer section 39. The outer section 39 may be disconnectable in some embodiments. Additional or substitute sections could also be incorporated. Each section is pivotable or hinged to each other so as to vary from being linear in the 15 fashion of Figure 3c, through to substantially downwardly perpendicular thereto (refer Figure 3a). Each section is also pivotable with respect to that to which it connects. In Figures 3, the outer 39 and intermediary 38 sections are maintained in a linear relationship to each other, though in Figure 4, the outer section 39 is shown to be folded with respect to 20 intermediary section 38. To attain the particular orientation of Figure 4, the main beam is straightened as in Figure 3c, and locking pins 40 removed to allow the outer sections 39 to drop. ;The carriage 3 is able to slide or travel along the main beam 31. The position and movement thereof is controlled by the wire cable 2 and the 25 sheaves 33-35. Anti-clockwise rotation of the sheaves, acts on the wire cable in a manner to draw the carriage 3 to the right. In Figure 3c, the ;25 ;* 234393 • 2360922375 carriage 3 is seen in its rightmost position. Conversely, clockwise rotation of the sheaves will draw the carriage to the left. A rotary motor 1 connected to each outer sheave 33 controls rotation thereof and ultimately, the position of carriage 3. These motors may be hydraulically powered. 5 The lifting assembly 32 comprises two sets of telescoping arms 14 which extend downwardly from the main beam 31 and which are substantially parallel one to the other. They are spaced apart by a distance typical of the average load. They may be linked directly to the sliding carriage 3 and may be disconnectable or repositionable with respect thereto. 10 Consequently, movement of the sliding carriage 3 may also cause travel of the lifting assembly 32. Other arrangements may also be adopted. For instance the lifting assembly 32 may be directly coupled to or ride on the main beam 31 such as by way of wheels 22 whilst the carriage 3 shunts the assembly 32 along the beam. 15 Each extending arm 14 comprises two or more sections which telescope one inside the other. Centrally within these, for the arms 14 illustrated which comprise two parallel telescoping sub-arms, two screws may be provided (one in each sub-arm). These screw or worm assemblies are connected to the sections of the arm such that by rotation thereof, 20 extension or contraction of the arms 14 may be effected. The drive for the worm or screw may be transmitted from a power unit 11 and its associated fuel pack 12. During assembly of the lifting device 30, the lifting arms 14 are extended from the contracted collapsed position, thus raising the main beam 25 assembly 31 above the deck of the carrying vehicle. At this stage, or even prior to lifting, the main beam 31 may be extended. At this point, it may be desirable to lock the telescoping arm sections with respect to each other, 26 234393 23609 3750 before the remainder of the assembly process is completed. Unless this is done, the entire weight of the straddle lifter is supported by the two or four screws. This does not represent a problem if the weight is evenly balanced over all of same, though it may bend or warp a screw shaft if the load 5 became unbalanced such as when the assembly 31 is extended to one side of the carrying vehicle (e.g. for the wide embodiment of Figure 5) or when the leg sets 17 are moved outwardly. By using locking pins to secure the telescoping arms sections 41 and 42 with respect to each other, the load is no longer carried entirely by the screws. 10 The leg sets 17 each comprise two telescoping legs 43. These are formed of two sections, one of which slides within the other. Extending same is achieved by removing a locking pin 44 and letting the lower section drop. Alternatively, cable 45 comprises two equal length sections which are joined. These connect the base of the lower section 47 to the leg carriage 48 15 and maybe used in addition to locking pin 44 or as a substitute therefor. The cable 45 also serves to limit the maximum spread of the legs 43 to each other. The leg carriage 48 is formed by the top of the leg upper sections 46. The leg carriage 48 couples the leg set 17 to the main beam 31, and is able to 20 travel therealong. Each leg 43 is pivoted to the carriage 48 about an axis substantially parallel to the longitudinal axis of the main beam 31. This allows the legs 43 to be splayed apart in a direction substantially perpendicular to said longitudinal axis of the main beam 31. This also allows the legs 43 to pivot with respect to the main beam 31 to 25 accommodate sloping or uneven ground. Surface irregularities may also be catered for by locking pin 44 which may cooperate with a series of aligning apertures in the two leg sections 46, 47, thus allowing a range of 27 90 234393 • 23609 2fe3750 leg heights to be chosen. Further locking means, may also be /provided to lock the carriage 48 with respect to the main beam 31, both with regard to travel therealong and pivoting thereto. The unfolding of the straddle lifter up to a stage of partial assembly has 5 been described. At this point, it is generally desirable to move the leg sets 17 outwardly towards the end of the load bearing section of the main beam. It is noted that these positions are different between the two different assembled states illustrated in Figures 4 and 5. The wire cable 2 and sliding carriage 3 may be used to move these leg sets 17 outwardly one at a 10 time. This merely involves connecting the carriage 3 to the appropriate leg set 17 (or more specifically the leg carriage 48) and moving it outwardly, disconnecting from same and repeating for the other leg set. It may now be desirable to extend the main beam 31 in one direction or the other, especially when the assembled configuration of Figure 5 is adopted. 15 At this point, the lifting assembly 32 should still be connected to the body of the truck. By connecting the carriage 3 to the lifting assembly 32, attempting move the lifting assembly 32 with respect to the main beam 31 will cause a shift of the main beam 31, in one direction or the other. To prevent tipping of a truck, it may be desirable to employ any hydraulic feet 20 24 thereon to stabilise the unit. When the main beam is at the correct position with respect to the carrying vehicle, the legs 43 may be extended and splayed to rest on the ground. Further comments will now be made directed to specific components of the straddle lifter. 28 734393 • 23 6 092/^5750 Hydraulic rotary motors 1 drive the outer sheaves 33 via a bevel gear. One bevel set of teeth is on the outer rim of the sheave. When both sheaves are rotated, the steel wire cable 2 is able to move relative to the beam 31. Movement of the steel cable 2 maybe used to achieve any of the following: 5 a) Movement of the lifting assembly 32 and a load along the beam i.e. in a lateral direction. b) With the arms 14 of the lifting assembly 32 secured to the carrying vehicle, shifting the beam sideways with respect thereto. c) Movement of the leg sets 17 with respect to the main beam. 10 The carriage 3 runs within guides for the full length of the beam 31 (unless the ends 39 are folded downwardly). Apertures in the carriage 3 allow either the lifting assembly 32 or leg sets 17 to be connected or disconnected thereto. Four hydraulic rams 4 (two only are apparent in Figures 3) push 15 outwardly on the two central sheaves 35. This action raises the beam ends (38, 39 combined) until they are locked or pinned into position. The shaft and body ends of each ram may be reversed between adjacent rams. Apertures 5 are provided for locking the various sections 37-39 with respect to each other. 20 Further apertures 6 are provided for locking or pinning the leg sets 17 into position with respect to the main beam 31. The outermost apertures are for the lifter in a light-load configuration while the intermediary apertures are for the heavier-load roll. The centermost apertures 6 are for when the lifter 30 is collapsed. 29 ?34 393 • 23 6 0 92(23 7 5 0 1 Further apertures 7 are also provided to maintain the orientation of sections 38 with respect to central section 37. The inner pins also provide a fulcrum point to fold or raise the beam ends. Pin 8 is -left out of the indicated aperture when the heavy-load 5 configuration is adopted, allowing the outer beam section 39 to fall downwardly. Curved member 9 is grooved and acts a fulcrum for the steel wire cable 2, especially during unfolding of the main beam 31. Each member 9 is attached permanently to each leg set 17 and therefore moves along the 10 beam 31 with them. This fulcrum is out of the way when the cable 2 starts running during operation of the straddle lifter 30. Centre reinforcing plates 10 join the two beams 36 together. Typically bolts or pins are provided so that the main beam assembly 31 may be dismantled for maintenance or fault correcting. 15 In a preferred embodiment, the power pack 11 contains a diesel-petrol motor and a hydraulic pump. The cube shown represents the appropriate volume occupied by a suitable unit. However there are a wide range of suitable motors available which have differing configurations and sizes. Several motors may be employed - this may allow the continued use of the 20 straddle lifter after failure of one. They may be situated elsewhere than where shown in the figures - for instance near the base of the legs which also reduces the load on the main beam assembly. Two 20kW hydraulic motors would normally be sufficient. Fuel for the motor 11 may be provided in a pack 12. This will presumably 25 also contain any hydraulic fluid. The shape may be adapted to be 30 ?34393 • '3 6 0 92123 7 5 0 complementary to the shape of the motor 11. Both the motor 11 and fuel pack 12 fold downwardly during collapse of the lifting device. The fuel pack 12 also extends downwardly and occupies a position slightly below and forwardly of the motor 11 during collapse. This is clearly seen in 5 Figure 6. Arms 13, provide for the downward folding of the motor 11 and fuel pack 12. The arm for the fuel pack 12 may also extend to enable said pack to be lowered, or alternatively, the pack may be dismantled from the arm 13 and lowered by hand or by a rope, cable etc. 10 Telescoping lifting arms 14 have a central screw controlling the extension. The screw is driven by a rotary hydraulic motor at either the top or base of the screw. In the illustrated embodiment, the load may be lifted by a total of 2.1m, this being limited by the lifting arm arrangement 14. If this is insufficient, 15 variations comprising multiple arm sections and/or screws may be employed or an alternative lifting system used. However, 2.1m is sufficient in most cases for use with road or rail going vehicles. It has also been noted that the lifting arms 14 may be used to raise a main beam 31 above the carry vehicle. It is desirable to use twist locks 16 to 20 secure the arms to the deck of the truck. Lugs 19 may also be employed to secure the lifting arms 14 to the carry frame 23 on the carry vehicle. A cable or chain 15 may be employed in conjunction with the lifting arms 14 to carry the load. This is readily seen in Figures 4 and 5. Twist locks 16 at the base of the lifting arms 14 are set at the correct 25 distance apart for engagement with standard ISO dimensions such as the 31 ' ' 234393 • 23 6 0 92(23 7 5 0 3m ISO container. Figure 4 shows two 3m containers arranged/end to end adjacently. Thus two containers may be lifted directly off a wagon or deck in one operation or may be transported singly as is apparent in Figure 5. It is noted however, that loads other than containers or devices 5 corresponding to standard ISO dimensions may also be lifted by the present invention. In some cases, special adaptors may be required though cables 15 allow for most loads to be lifted without any great difficulty. These cables may be replaced by telescoping arms - useful for balancing or counteracting unevenly distributed loads within a container. 10 The leg sets 17 comprises two legs 43 which may be pinned or locked into positioned for the required height. Typically each leg will extend to a maximum of approximately 5m, giving an overall working height of around 5.8m. The cable 18, 45 limits the spread of the legs 43. Provision may be made for tightening the cable with respect to the legs for in 15 instances where a reduced spread is required. This cable may also be disconnected at its centre and used to secure the legs in a non-extended form (typically to the main beam) after or during collapse. The lug 19 sits into a recess on the frame 23 of a truck and helps guide the straddle iifter into place during collapse. 20 Base plates or feet 20 take the live and dead load of the lifter. They may be taken off and stowed when the straddle lifter is remounted onto the truck, as is evident in Figure 6. Also, they should be left off the legs when booming or shifting the main beam 31 to one side of the truck during assembly (light-load configuration). This gives greater clearance over any 25 obstacles or adjacent vehicles. 32 234393 23 6 0 92123 7 5 0 Ground traction wheels 21 may be provided for moving the straddle lifter with respect to the ground. These wheels may use either tyre pressure or a string to lift the base plate 20 off the ground (i.e. they lift the entire straddle lifter off the ground). However this is normally only when there 5 is no live load on the straddle lifter. Once the live load is supported by the straddle lifter, the base plate is forced back into contact with the ground again. Provision may be made, that when the wheels are in contact with the ground (no load situation) that they may be locked into position to enable a load to be carried. However such an embodiment would require 10 non-pneumatic tyres and a much stronger wheel axle assembly. Each wheel may have its own hydraulic rotary motor to drive it. A frame 23 is provided on the carrying vehicle to help maintain the collapsed straddle lifter in place. Hydraulic rams and feet may be provided on the carrying vehicle, to help 15 stabilise the vehicle during assembly of the straddle lifter. A cable 45 when split (refer Figure 7) can be used to allow the legs to drop part way down onto the truck after the main beam is raised. After the main beam has been positioned and subsequently lowered, the lower legs come into contact with the ground. This allows the cable to go slack. The 20 cable may now be disconnected from the upper leg section 46 and reconnected to join the other section of cable on the opposing leg. This method is a variation of that previously described. Generally during erection of the lifting device, and especially when booming the main beam to one side (refer Figure 7) the legs are kept in 25 their non-splayed apart form so that they may be readily fitted between 33 23439 • 23609 2^375 gaps between vehicles should they be present during erection. Figure 7, shows the leg set having travelled through the gap between adjacent railway wagons. Small spacing blocks 49 may be provided to help maintain the legs in a 5 splayed position and may also help resist any substantial pendulum-like movement between the main beam and leg set. These may be flicked out the way during collapse of the lifting device, allowing the splayed legs 43 to revert to their close together position. Figure 8 shows further detail of the main beam assembly, near its middle. 10 The top end of the screws 50 are visible. Typically these screws will move upwardly and downwardly with the lower lifting arm sections 42. With further reference to Figure 8, there is seen axle 56 for wheel 57 running along the beam 31. 58 shows the web of the beam while the RHS upper section of the beam is shown at 59. The axis by which the legs 43 15 attached to the leg carriage 48 is seen at 61 where a pin passes through the illustrated aperture 61. 64 illustrates the central tube 35 in cross-section, this sheave being spaced apart by the hydraulic rams 4 during their operation. Typically this sheave 35 is of 300mm diameter. 20 66 illustrates the connection between the shaft 65 which interconnects diagonally paired hydraulic rams 4 which also connect to the sheave bush 67. 68 illustrates the shaft for sheave 35 and bush 67. 70 indicates the position of the other central sheave 35, which is slightly diagonally offset (in cross-section) to the sheave thus far described with 25 reference to Figure 8. It is also noted that while the two central sheaves 35 34 234393 23 6 0 92123 75 0 1 are thus diagonally inclined, they are aligned at the bottom to allow a single run of the steel cable two to pass therethrough. Guides 71 are provided for the sliding carriage 3. 73 illustrates the section of a travelling carriage of the lifting assembly which holds the pins 74. 5 This pin 74, which can move up and down to engage or disengage a hole in the sliding carriage 3, connects to the carriage of the lifting assembly. Collapse of the straddle lifter is essentially a reversal of the steps of assembly described herein. Various subtle differences or changes in the order by which steps are performed, may be necessary though this would 10 be readily apparent to a skilled addressee of the art. It is also noted that assembly of the straddle lifter need not be conducted in the exact order described herein. Other variations are permissible. Further, other embodiments of straddle lifters, may also vary significantly in their manner of operation and assembly than in the specific embodiment 15 described here. Figures 9-14 illustrate a further variation of the present invention. The embodiment of these figures is adapted to stow on the deck of a truck or railway wagon and is secured to standard twist-lock mounts on the deck. The series of figures illustrate the gradual unfolding of the main beam 20 assembly into a narrow-form, followed by travel of the leg sets (in Figure 12) to the ends of the erected narrow-form main beam assembly. During this period, the assembly is supported above the deck by the load-lifting arms which are rigid. In this embodiment, the lifting arms have an inside telescoping section enabling them to be extended to hold and lift a 25 load (refer Figures 13 and 14). When the bulk of the straddle lifter is being supported (refer Figure 12) it is usual that the lifting arms are in a non-telescoped state. 35 234393 • 23609 2/2 3750 Figure 13 illustrates use of the straddle lifter in its narrow-form 26 tonne mode. It is noted that if this is the predominant form of use for a particular straddle lifter, then the outer most folding section of the main beam assembly may be removed or omitted from the lifter. 5 In Figure 13, a load is lifted from a truck deck and the truck is driven away. The load may then be placed on the ground and the straddle lifter re-positioned for another operation. Alternatively, another vehicle (refer Figure 14) may be placed under the load and the load gradually lowered thereon. 10 Figures 15-20 illustrate essentially the same embodiment as in Figures 9-14 though the embodiment has been stowed on a railway wagon and gradually unfolds into a wide-form. Again the unfurling of the main beam assembly can be seen in Figures 15-18 and outward travel of the leg set along the support main beam assembly seen in Figure 19. One typical 15 use of the straddle lifter in its wide-form 13 tonne mode is illustrated in Figure 20. It is noted also in the embodiments illustrated in Figures 9-20, that two sets of hydraulic motors have been provided, these being split between each leg set. This lowers the center of gravity for the apparatus and reduces the 20 total load supported by the main beam assembly. It is also noted that various embodiments of the present invention can be adapted for other roles. For instance, it has been noted that various embodiments of a straddle lifter are wheeled. Depending on the wheel and/or carriage assembly provided for mobility, it may be possible for some 25 embodiments to be mobile while carrying a load. This adapts the straddle lifter into a role where it can be used to transport containers or load about 36 ?34393 f '3 6 0 92k j j 5 ( a depot or warehouse. This also adapts it into a multi-role piece of equipment able to form an economical substitute for (in some instances) a common forklift and with a much greater load carrying capacity then many conventional fork-lift vehicles. The lifting assembly may be further 5 adapted to be able to transport other loads such as logs, skips or loads (such as logs) confined in bolster assemblies. For logs, two straddle lifters may be used - one to support each end of the log load. Figures 21 and 22 illustrate close-up detail of the top portion of a leg set where it meets the main beam assembly on the embodiments of Figures 9-10 20. The pivotal connection between each leg can be clearly seen in Figure 21 as can the pivot arrangement for the downward (unfolded) outer most section of the main beam assembly. Figure 22 shows detail of the underside again showing in detail the pivotal inter-relationships between the various components and the positioning of 15 relocatible rams which may be used to push the leg sets outwardly along the main beam assembly. Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the 20 appended claims. 37 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> WHAT I CLAIM IS:

1. A collapsible straddle lifter comprising: an extending, collapsible main beam assembly having a main load-bearing portion; at least two extending, collapsible leg sets, of which there is at least one positioned near each end of either an erected said main beam assembly or main load-bearing portion thereof, and a lifting assembly coupled to said main beam assembly. 2. A collapsible straddle lifter as claimed in claim 1 wherein said main beam assembly is erectable into more than one configuration which have differing spans. 3. A collapsible straddle lifter as claimed in either claim 1 or claim 2 wherein an erected main beam comprises a load-bearing portion and a cantilevered portion of a lesser load bearing capacity. 4. A collapsible straddle lifter as claimed in any one of the preceding claims wherein said main beam assembly comprises several parallel beam sections. 5. A collapsible straddle lifter as claimed in any one of the preceding claims wherein said main beam assembly includes telescoping members. 6. A collapsible straddle lifter as claimed in any one of claims 1 to 4 wherein the main beam assembly includes folding, hinged and/or pivotable members. 7. A collapsible straddle lifter as claimed in any one of the preceding claims wherein a capstan and cable arrangement is provided .for assisting the erection of a collapsed main beam assembly. 38 V ./ 15. ® 16. 17. A collapsible straddle lifter as claimed in any one of the preceding claims which includes locking members for an erected main beam assembly. A collapsible straddle lifter as claimed in any one of the preceding claims wherein a leg set comprises at least two adjoining legs. A collapsible straddle lifter as claimed in claim 9 wherein said legs are outwardly splayed in an erected straddle lifter. A collapsible straddle lifter as claimed in either claim 9 or claim 10 wherein said legs are collapsible/extendible. A collapsible straddle lifter as claimed in claim 11 wherein said legs include telescoping members. A collapsible straddle lifter as claimed in claim 12 wherein telescoping movement is performed by a screw, hydraulic or pneumatic mechanism. A collapsible straddle lifter as claimed in any one of claims 11 through 13 wherein said legs are capable of raising said main beam. A collapsible straddle lifter as claimed in claim 14 wherein said legs are capable of raising said main beam and a load. on A collapsible straddle lifter as claimed in any one of claims 11 through 15 wherein said legs include folding, hinged or pivotable members. A collapsible straddle lifter as claimed in any one of claims 9 through 16 which includes a stay between the legs of an erected straddle lifter. A collapsible straddle lifter as claimed in any one of claims 9 through 17 wherein at least one leg includes a foot at its base. 39 £3 19. A collapsible straddle lifter as claimed in claim 18 wherein a foot includes one or more wheels for ground travel thereof. 20. A collapsible straddle lifter as claimed in claim 19 wherein said wheels are retractable and biased to protrude when the straddle lifter is not carrying a load. 21. A collapsible straddle lifter as claimed in either claim 19 or claim 20 including drive means to propel the straddle lifter with respect to the ground. 22. A collapsible straddle lifter as claimed in any one of the preceding claims wherein a leg set may travel longitudinally with respect to said main beam assembly. 23 A collapsible straddle lifter as claimed in claim 22 wherein one or more leg sets are positioned near the middle of the main-beam assembly when the straddle lifter is in a collapsed state. 24. A collapsible straddle lifter as claimed in any one of the preceding claims wherein said lifting assembly is capable of raising, or assisting in raising the main beam assembly. 25. A collapsible straddle lifter as claimed in any one of the preceding claims wherein said lifting assembly comprises a screw, hydraulic or pneumatic mechanism. 26. A collapsible straddle lifter as claimed in any one of the preceding claims wherein said lifting assembly is capable of travel longitudinally with respect to said main beam assembly. ii- 12 WAY 199'' c 40

2.1 *;27. A collapsible straddle lifter as claimed in any one of the preceding claims wherein the lifting assembly is capable of connection to ISO dimensioned 'twistlock' type fastening points on a load.;28. A collapsible straddle lifter as claimed in any one of the preceding claims which includes power means for assisting in the erection and/or operation of at least one of the main beam assembly, a leg set and the lifting assembly.;29. A collapsible straddle lifter as claimed in claim 28 wherein hydraulic or pneumatic power means is provided.;30. A collapsible straddle lifter as claimed in any one of the preceding claims in which the main beam assembly is able to span over a container carrying flat deck railway wagon.;31. A collapsible straddle lifter as claimed in any one of claims 1 through 29 in which the main beam assembly is able to span over either:;two conventional railway wagons on adjacent tracks, or a conventional truck and trailer unit adjacent to a container carrying flat deck railway wagon on a track.;32. A collapsible straddle lifter as claimed in any one of claims 1 through 29 which may be erected into more than one configuration, wherein in the first of said configurations the main beam assembly is capable of spanning a conventional railway wagon on a track whilst in the second said configuration the main beam assembly is capable of spanning either:;two conventional railway wagons on adjacent tracks, or a conventional truck and trailer unit adjacent to a container carrying flatdeck railway wagon on a track.;3

3. A collapsible straddle lifter substantially as described herein with reference to the accompanying diagrams.;VAIL MARTIN JOHN HUBNER by his Attorneys;JAMES &/WELLS;42* </div>