WO2014172748A1 - Improvements relating to the lifting of gridmesh - Google Patents

Abstract

In one preferred form there is provided a lifting device (600). The lifting device (600) comprises an upper portion (602) able to be lifted by a crane and a lower portion comprising a number or foot portions (606, 608). The foot portions (606, 608) extend in opposite directions and provide a foot (612). The foot (612) is able to be inserted through a grid opening (614) of a sheet of grid mesh (605) between the bars of the grid mesh (605), when the foot (612) is rotated to a first orientation. The foot (612) is able to be rotated to a second orientation in which the foot (612) is unable to be withdrawn from the grid opening (614) through which the foot (612) was inserted due to each foot portion (606, 608) extending in opposite directions to each bear against the grid mesh from below.

Description

SYSTEMS AND ME HODS FOR LIFTING GRIDMESH FIELD OF THE INVENTION

In preferred forms, the present invention concerns the lifting of gridmesh panels at a building or industrial site.

INCORPORATION BY REFERENCE

Priority is claimed from and the following applications are incorporated by reference for al l purposes.

1) AU2 13901427; Improvements Relating to the Lifting of Gridmesh; Filed

2013-04-23

2) AU2013I00816; Improvements Relating to the Lifting of Gridmesh; Filed

2013-06-11

3) AU2013101149; Improvements Relating to the Lifting of Gridmesh; Filed

2013- 08-29

4) PCT/IB2014/058372; Improvements Relating to the Lifting of Gridmesh; Filed

2014- 01-18

BACKGROUND TO THE INVENTION

Gridmesh panels often need to be lifted into position by a crane o a building or industrial site such as an offshore platform. Gridmesh panels also often need to be manually moved by a number of workmen on-site,

Gridmesh is the type of rigid open grid panels commonly used for the flooring of work platforms and walkways in exposed areas of industrial sites. There are a variety of configurations. Most gridmesh is of mild steel construction hot dip galvanized to protect it from corrosion, but other materials such as stainless steel, in food handling operations, and plastics are also used. In some configurations each panel is made of steel bars and consists of a perimeter frame surrounding a first array of flat bars parallel to and spaced from each other with a gap of about 2cm to 3cm between adjacent bars, plus a second array of bars aligned transversely to the first array and welded to those first bars. The bars in the second array may be round or flat.

The second array is commonly welded directly on the top surface of the first array, but some versions of gridmesh have the second array recessed wholly or partly into the first array. Usually the spacing between the bars in the second arra is substantially greater than the spacing between the bars in the first array so the apertures through the panels take the form, of elongated slots.

Other configurations of gridmesh comprise panels of integrally moulded plastics material. These are sometimes used in offshore marine situations and other corrosive environments. In these configurations the first and second array s are of the same size and spacing so the apertures throug the panels are square.

Further configurations of gridmesh are formed as expanded metal mesh where sheet metal is first slit discontinuously and then stretched to open the slits out into apertures. Again the apertures are not very large.

The lifting of such panels by crane is often awkward because the bars in the grid are spaced too close together for a conventional crane hook to slide between them. Timesaving but unsafe practices are sometimes adopted which can allow the panels to sometimes accidentally slide out from a sling. Usually however a shackle and/or sling arrangement needs to be threaded through the apertures and the crane hook engaged with the shackle or sling. This can be awkward to engage and disengage.

It would be preferred for gridmesh panels to be lifted with their major plane in a generally horizontal alignment so the panel does not tilt or swing during the lifting operation and to facilitate easy stacking/positioning of the panels when the are being unloaded from the crane. When gridmesh panels are lifted by the methods described above, it can be difficult to get them to lift in a neat substantially horizontal manner. It is to be recognised that any discussion in the present specification is intended to explain the context of the present invention. It is not to be taken as an admission that the material discussed formed part of the prior art base or relevant general knowledge in any particular country or region.

S U MM ARY OF H E I VE N T I O

According to an aspect of preferred embodiments herein described there is provided a method of lifting a panel of gridmesh on a building site, said gridmesh comprising a plurality of interlinked bars with apertures between the bars, and said method comprising: inserting a foot of a lifting device downwards between a pair of adjacen bars, with the lifting device in a first orientation; rotating the lifting device to a second orientation and engaging said foot with a lower surface of at least one of said pair of bars; and lifting the panel by means of the lifting device so engaged; wherein: said lifting device comprises an upper portion for being lifted; and said foot of the lifting device comprises two foot portions separated from each other and which engage the panel beneath said lower surface of at least one of said pair of bars.

Preferably the upper portion comprises a ring to which, in use, a crane is attached. Preferably the method comprises using the crane to lift the panel, the panel comprising walkway gridmesh.

Preferably the ring is centrally positioned relative to the foot to assist with balancing the weight of the panel Preferably the ring is centrally positioned above the foot. Preferably the central position of the ring assists with balancing the weight of the gridmesh.

Preferably the foot provides a slot for holding the at least one of said pair of bars; and the foot includes a portion above the slot that is provided as a bend to centrally position the ring above the slot.

Preferably the foot provides a slot for holding the at least one of said pair of bars; and the lifting device comprises a shank that extends between the ring and the foot; the shank being configured to centrally position the ring above the slot.

Preferably the lifting device comprises a shank having a lifting end, a foot end and an intermediate portion therebetween; the lifting end being laterally spaced apart from the foot end to centrally position the ring relative to the slot. Preferably the intermediate portion comprises a bend to laterally space apart the lifting end and the foot end; the lifting end being connected to the ring; and the foot end being connected to the foot. Preferably the lifting end and the foot end of the shank are substantially parallel and the intermediate portion comprises a bend connecting the lifting end and the foot end of the shank.

Preferably the bend comprises a relatively straight portion having two bends of about 45 degrees at each end of the bend. Preferably the bend comprises a relatively straight portion having two bends of about 22.5 degrees at each end of the bend.

Preferably the device provides a body ha ving two slots for holding a first bar of the at least one pair of bars, the first bar being held in a position with the two slots receiving and spaced apart along the first bar; the ring being centrally positioned directly above the first bar; and centrally positioned between the slots.

Preferably the method comprises using a number of the devices, each device being lifted by a respective workman to lift the gridmesh.

Preferably the upper portion comprises a handle for being lifted manually by a workman. Preferably the handle includes a shank that is configured to be threaded into the body of the device. Preferably the handle including the shank is at least 450mm long. Preferably the device including the handle and shank is at least 600mm tall.

Preferably the handle extends laterally to provide a portion that extends fully across the workman's hand when gripped, in preferred forms, the handle is laterally offset from the foot to assist with spacing the handle away from the gridmesh during lifting. Preferably the lifting device comprises a shank that extends between the handle and the foot; the shank being configured to offset the handle from the foot. Preferably the offset position of the handle assists with protecting a workman's shins when the workman is walking forwardly and carrying the gridmesh therebehind, rearward of the workman.

Preferably the lifting device comprises a shank having a lifting end, a foot end and an intermediate portion therebetween, the lifting end being laterally spaced apart from the foot end to space the handle portion away from the grid mesh to assist with allowing a person to relocate the gridmesh once lifted. The intermediate portion may include a bend to laterally space apart the lifting end and the foot end; the lifting end being connected to the handle; and the foot end being connected to the foot. Preferably the lifting end and the foot end of the shank are substantially parallel and the intermediate portion comprises a bend connecting the lifting end and the foot end of the shank. Preferably the bend comprises a relatively straight portion having two bends of about 45 degrees at each end.

Preferably said gridmesh comprises metal bars forming a rectilinear grid having: a first array of said bars parallel to and spaced from each other, and a second array of said bars parallel to and spaced from each other, and aligned transversely to the bars in said first array. The metal bars may be welded together or integrally formed to provide the rectilinear grid.

Preferably said lifting device comprises a shank extending between said ring and said foot and extending between said pair of bars, said foot portions extending in opposite directions from said shank, and said lifti g device being rotated after insertion between said pair of bars, such that said shank extends between said pair of bars, and said engagement of the foot portions with the panel is such that each said foot portion engages a different one of said pair of bars.

Preferably a flange extends from said shank immediately below said ring.

In one embodiment, said lifting de vice comprises a pair of spaced apart legs which extend down between said pair of bars; each said leg has a respective foot portion extending laterally therefrom; and each said foot portion engages beneath the same one of said pair of bars.

Preferably said lifting device has a bifurcated member which engages the panel astride one of the bars in said second array .

Preferably said foot portions include recesses on their upper surfaces into which said lower edge (surface) of said at least one bar is located.

Preferably the device comprises two hook portions providing recesses for engaging the grid mesh either side of one or more bars of the gridmesh. According to another aspect of preferred embodiments herein described there is provided a lifting device comprising: an upper portion that is able to be lifted and a lower portion comprising two foot portions; the foot portions extending in opposite directions and providing a foot; the foot being able to be inserted through a grid opening of a sheet of grid mesh between the bars of the grid mesh, whe the foot is rotated to a first orientation, and then be rotated to a second orientation in which the foot is unable to be withdrawn from the grid opening through which the foot was inserted, due to the foot portions of the foot extending in opposite directions to each bear against the grid mesh from below. v Preferably the upper portion comprises a shank having a ring structure at a first end of the shank, the ring structure able to be lifted by a crane; the two foot portions extend in opposite directions transversely from the shank; and the foot portions are provided at an opposite end of the shank to the ring structure.

Preferably the ring and shank are centrally located between the foot, portions.

Preferably the upper portion comprises a shank having a handle at a first end of the shank, the handle able to be lifted by a workman; the two foot portions extend in opposite directions transversely from the shank; and the foot portions are provided at an opposite end of the shank to the handle.

Preferably the foot portions include eieraents adapted to engage further grid openings of the grid mesh when in the second orientation, the ^'further grid openings engaged by the elements being located in the vicinity of the grid opening through which the foot member is able to be inserted.

Preferably the elements are provided by a regular spacing of recesses in the upper surface of the foot member.

Preferably the lifting device includes a safety arrangement for securing the elements in position and preventing them from being removed from the further openings.

Preferably the lifting device includes a safety arrangement provided in the form of a retaining pin able to secure the elements in position and prevent them from being removed from the further openings. Preferably the lifting device includes a biasing arrangement for biasing the gridmesh downwardly to assist with holding the gridmesh in position on the foot. Preferably the biasing arrangement includes a holding element slidably mounted to the shank. Preferably the biasing arrangement includes a spring that is coiled around the shank for urging the holding element downwardl to push the gridmesh towards the foot, in the condition where the foot is unable to be withdrawn from the grid opening.

Preferably the holding element includes a number of notches for engaging the grid mesh when urging the grid mesh towards the foot. Preferably the notches are provided in the surface of the biasing element facing the foot. Preferably the notches are aligned with corresponding notches provided in the foot.

According to another aspect of preferred embodiments herein described there is provided a lifting device comprising: a shank member having a lifting portion and an anchor portion, the anchor portion being able to be inserted through a first grid opening of a sheet of grid mesh, when in a first orientation; the anchor portion comprising at least two elements able to engage further grid openings spaced apart from the first grid opening when the anchor portion is rotated to a second orientation, once inserted through the first opening, the engagement provided by the at least two elements with the further openings, able to prevent rotation of the anchor portion to the first orientation during lifting.

Preferably the two elements comprise two support members that extend transversely, in opposite directions, fro the lifting portion, the support members having a number of recesses between upper areas, the upper areas being shaped to be received in the further openings,

Preferably each support member includes the recesses as a pair of notches, each pair of notches for engaging two bars of a grid mesh panel when the anchor portion is positioned for lifting is in the second orientation underneath the grid mesh panel.

Preferably rotating the anchor portion from the first position by 90 degrees in the general plane of the grid mesh disposes the anchor portion in the second position.

Preferably the lifting device includes a safety arrangement for securing the at least two elements in position and preventing them from being removed from the further openings. Preferably the lifting device includes a safety arrangement provided In the form of a retaining pin able to secure the at least two elements in position and prevent them from being removed from the further openings.

According to an aspect of preferred embodiments herein described there is provided a lifting device comprising: a body having an upper portion and a lower portion; the upper portion for being lifted; and the lower portion providing a pair of legs each having a foot member having a downwardly extending groove for engaging a first bar of a sheet of grid mesh; the legs for sitting astride at least one other bar of the grid mesh, the or each other bar being aligned transversely to the first bar.

Preferably the connection lifting device allows for selective connection of a lifting ring or a shaft type lifting handle

Preferably the legs are configured to sit astride a single other bar of the grid mesh.

Preferably the upper portion includes a connection portion, the connection portion for fixing a lifting element thereto, the connection portion providing an opening for receiving a shank.

Preferably the connection portion allows for selective connection of a lifting ring or a shaft type lifting handle.

Preferably the opening faces upwardly to allow the lifting element to be positioned at an upper position.

Preferably the connection portion prov ides a threaded aperture for receiving a threaded shank of a bolt.

Preferably the device includes a ring that is adapted to be mounted with the use of a bolt that is threaded into the opening, the bolt providing a swivel point for the ring. In another embodiment the device includes elongate handle for being threaded into the opening.

Preferably the elongate handle extends to space a hand grip portion of the handle away from each groove of each foot member in a manner assisting with limiting any impact to the shins of a person carrying the grid mesh.

Preferably the elongate handle is at least 400mm long to provide the lifting device with a length of at least 600mm. Preferably the upper portion provides an enlarged head portion.

Preferably the pair of legs of the lower portion are spaced apart by 10mm or more.

Preferably the pair of legs of the lower portion are spaced apart by 20 mm or more.

Preferably the pair of legs of the lower portion are spaced apart to span a grid mesh opening.

Preferabiy the pair of legs of the lower portion are spaced apart by about the width of a grid opening of the gridmesh and two bars extending therealong,

Preferabiy each downwardly extending groove is configured to neatly support the depth of the first bar.

Preferabiy each downwardly extending groove is at least 40mm deep.

Preferabiy each downwardly extending groove is at least 50mm deep.

Preferabiy each downwardly extending groove is about 10mm deep.

Preferably the legs are provided for sitting astride a single other bar of the grid mesh, the other bar being aligned transversely to the first bar.

Preferabiy the device includes a safety catch for assisting with ensuring that the lifting device does not become separated from the gridmesh. Preferabiy the safety catch extends across the second bar that the legs of the lifting device sit aside. Preferably the safety catch extends across each groove of the pair of legs.

Preferabiy the safety catch comprises a singular plate that extends across each groove of the pair of legs; and which extends across the second bar that the legs of the lifting device sit astride. By extending across the second bar that the lifting device sits astride and by comprising a single plate a robust device can be provided. Preferabiy the singular plate is biased towards the posi tion in which the safety catch extends across each groove of the pair of legs.

Preferabiy the body is provided as main body having the pair of legs extending therefrom, with the plate mounted to the main body, away from the terminal ends of the legs, so as to be moveable to and from a position in which the plate extends across each groove of the pair of legs; the plate being rotationally pivoted to the main body to allow the device to be secured in position on the bar and then be removed from the first bar as required. Preferably the safety catc comprises a plate rotation ally pivoted on the main body- Preferably each foot member has an upwardly extending toe portion extending upwardly to provide a slot for engaging the first bar of the sheet of grid mesh.

Preferably the lower portion is able to be inserted through corresponding grid openings of the sheet of grid mesh and, without rotation, be moved sideways towards the first bar and be unable to be withdrawn from the grid opening by each foot member bearing against the first bar.

The safety device may include a safety catch for engaging the second bar which the device sits astride.

According to another aspect of preferred embodiments herein described there is provided a method of lifting a panel of grid mesh, said method comprising: interesting a foot of a lifting device through grid openings of a sheet of grid mesh, engaging two foot portions with a lower surface of one of the bars of the gridmesh; and lifting the panel by means of the lifting device so engaged.

Preferably engaging the two foot portions comprises, without rotation, moving the lifting device downwardly through the grid openings, sideways towards the first bar and then upwardly to engage the first bar so as to be unable to be withdrawn from the grid opening by each foot member bearing against the first bar. Preferably th lifting device provides a double hook portion.

According to another aspect of preferred embodiments herein described there is provided a lifting device for lifting gridmesh having a number of interlinked bars, the device comprising an upper portion and a lower portion; the upper portion including a shank; the lower portion comprising two foot portions providing a foot member; the two foot portions extending in opposite directions transversely from the shank to provide the foot member; the foot member being able to be inserted through a grid opening of a sheet of gridmesh between the bars of the gridmesh, when the foot member is rotated to a first orientation, and then be rotated to a second orientation in which the foot member is unable to be withdrawn from the grid opening through which the foot member was inserted due to the two foot portions bearing against the gridmesh. n

According to another aspect of preferred embodiments herein described there is provided a lifting device comprising: a body having an upper portion and a lower portion; the upper portion for being lifted; the lower portion providing a pair of legs each having a foot member having a downwardly extending groove for engaging a first bar of a sheet of grid mesh; the legs for sitting astride a second bar of the grid mesh, the second bar being aligned transversely to the first bar; and a connection portion allowing for selective connection of a lifting ring or a shaft type lifting handle.

It is to be recognised that other aspects, preferred forms and advantages of the present invention will be apparent from the present specification including the detailed description, drawings and claims.

B RI EF D E S CRI PTIO N O F D RAWI NG S

In order that the invention may be more folly understood there will now be described, by way of example only, preferred embodiments and other elements of the invention with reference to the accompanying drawings where:

Figure I shows a lifting device according to a first embodiment of the invention:

Figure 2 shows part of the lifting device illustrated in Figure 1 when being used to lift a panel of a first configuration of gridmesh, with part of the gridmesh shown in phantom;

Figure 3 is a downwards view showing the way in which the lifting device in Figure 1 is hooked onto a second configuration of gridmesh panel;

Figure 4 is a view of a lifting device according to a second embodi ment of the invention;

Figure 5 is a central cross section view along the length of a lifting device according to a third embodiment of the invention;

Figure 6 is a side view of a lifting device according to a fourth embodiment of the invention;

Figure 7 is a front view of the lifting device in Figure 6 shown when lifting a third configuration of gridmesh panel; Figure 8 is a side view of a lifting device according to a fifth embodiment of the invention when lifting a gridmesh panel of the first configuration;

Figure 9 is a front view of the device in Figure 8; and

Figure 10 is a side view of a lifting device according to a sixth embodiment of the invention when lifting a gridmesh panel of the first configuration;

Figure 1 1 is a front view of the device in Figure 10;

Figures 12a and 12b shows a lifting device according to another embodiment of the invention;

Figure 13a and 13b shows a lifting device according to another embodiment; and

Figures 14a and 14b show's a lifting device according to another embodiment, the lifting device having a catch of a first configuration; and

Figures 15 to 24 illustrate yet further preferred embodiments of the present invention. D ET A I LE D D E SC R I PTI ON O I TH E EM B OD IM E N TS ft is to be appreciated that each of the embodiments is specifically described and that the present invention is not to be construed as being limited to any specific feature or element of any one of the embodiments. Neither is the present invention to be construed as being limited to any feature of a number of the embodiments or variations described in relation to the embodiments.

The lifting device 10, according to a first preferred embodiment is shown in Figure 1 , and partly in Figure 2, is made entirely of steel. It comprises an upper portion 12 including a circular eye or ring 14, a lower portion 16 including a foot 18, and an intermediate portion 19 including a circular shaft 20 carrying a thread 22 on its lower portion 21 but having a smooth surfaced, unthreaded upper portion 28.

The shaft 20 has captive upon it a disc-shaped locking member 24 having a threaded central bore 26 (not visible in Figure 1) through which the shaft 20 passes and a knurled rim 25. The disc 24 is free to slide up and down on the unthreaded upper portion 28 but it's threaded bore 26 mates with the thread 22. The diameter of the unthreaded upper portion 28 of the shaft 20 is a little less than the root diameter of the thread 22 so the disc 24 is free to spin on the unthreaded upper portion 28 of the shaft.

The foot 18 is formed from flat metal plate aligned vertically and is securely fastened to the lower portion 21 of the shaft. The ring 14 is securely fastened to the upper portion 28 of the shaft 20, so the disc 24 is held captive on the shaft.

In one method of making the device 10, the eye 14, shaft 20 and foot 18 are manufactured separately and then welded together while incorporating the disc 24 captive on the shaft. Alternatively the shaft and eye can be formed integrally as a single forging.

Two notches 30 and 32 are recessed into the top edge (surface) 34 of the foot 1 8. The width and spacing of the notches 30 and 32 are such that the main bars 36 of the grid 38 are aligned generally centrally through the notches when in engaged with the lifting device 10 as indicated in Figure 2.

Only a small section of the gridmesh panel 38 is shown in Figure 2. The panel 38 comprises a rectilinear grid formed by a first array of main bars 36 laid parallel to each other and a second array of secondary bars 37 welded to the top edges 44 of the main bars and at right angles to the main bars. The secondary bars 37 stand proud of the top edges 44 and provide skid resistance to foot traffic as well as lateral support to the main bars 36. The panel 38 also has a peripheral rectangular frame 3 (shown in Figure 3 ) of bars the same as the main bars 36. The device 10 is considered to provide a lifting device 10 comprising an upper portion 12 able to be lifted by a crane and a lower portion 16 comprising a number or foot portions providing a foot or foot member 18, The foot member 18 is able be inserted through a grid opening of a sheet of grid mesh between the bars of the grid mesh with the foot member being in a first orientation. The foot member 18 is then rotated to a second orientation as described in which the foot member 18 is unable to be withdrawn from the grid opening through which the foot member was inserted due to the foot member 18 bearing against the grid mesh. Figure 3 illustrates a pair of lifting devices 10a and 1.0b the same as device 10 being installed ready to lift the gridniesh panel 40. For clarity the devices 10a and 10b have been sectioned below the disc 24.

Whereas the gri.dm.esh panel 38 shown in Figure 2 has the bars in the secondary array 1.0 formed from round section steel and welded across the top edges of the main bars, the secondary bars 42 in Figure 3 have the same cross section as that of the main bars 36 and are welded between the main bars 36.

To install the lifting device 10 ready for lifting the gridmesh pane! 40, the foot 18 is slipped down through the elongate gap 41 between a central pair of main bars 36 to be in the position show for the device 10a in Figure 3. The disc 24 is at this stage on the unthreaded upper portion 28 of the shaft. The lifting device is then twisted through 90° as indicated by the arrows marked A, and lifted to engage the two adjacent bars 36 with the notches 30 and 32. The disc 24 is then spun by hand to engage with the thread 22 such that the disc runs down the shall 20 until it bears lightly upon the top edges 44 of the bars 36 and thus acts as a locking member to prevent the bars 36 from coming out of the notches 30 and 32. The lifting device 10b is shown in that position in Figure 3. The knurled rim 25 on the disc provides secure finger grip when wet. The diameter of the disc 24 is sufficient for the disc to extend beyond the closest ba 36 on each side.

The eye or ring 14 is engaged with a shackle, or directly with a crane hook, to lift the panel. A pair of lifting devices 10 are preferably used in conjunction, joined by a chain with a central ring through which a crane hook is engaged. Four lifting devices 10 may alternatively be linked by four respective chains to a central ring for a more stable quad lift of a panel or panels.

In a variation of the device shown in Figure 1 , the ring 14 is turned at 90° to the foot 18.

The lifting device 1 10 shown in Figure 4 has many similarities with device 1.0 in Figure 1. It has a ring 1 14 in its upper portion 1 12 and a transversely extending foot 1 18 in its lower portion 1 16. However the foot 1 18 in device 1 10 has a pair of notches 130, 131 and 132, 133 let into the top edge 134 of the foot on either side of the central shaft 120 so that when lifting a panel of gridniesh, the foot engages four main bars of the gridmesh panel. The device 1 10 has no thread on Its shaft 1.20, and no disc-shaped locking member, but does have a pair of latching arms 127 that each 10 pivot about a pin 128. The arms 127 tilt upwards individually to allow the device 1 10 to be rotated into position but the amis 127 then drop down into a horizontal latched position as shown in Figure 4 to prevent the main bars of the panel from corning out of the notches 130-133.

The lifting device 210 illustrated in Figure 5 in cross section has an eye 214 and flange 223 in its upper portion. The flange 223 is wider than the gap between the main bars of the gridmesh so the device 210 cannot accidentally fall through the gndmesh. The lower portion of the shaft 220 is bent by about 30° transverse to the plane of the foot 218. This variation allows the transversely extending foot 218 of the device 210 to be aligned generally vertically so that the notches therein better engage the bars of the gridmesh panel even though the upper portion of the shaft 220 is aligned at 30° to the vertical because both devices 210 used for lifting the panel are suspended by chains from a single crane hook with the two arms of the chain subtending an angle of about 60°.

The lifting device 310 shown in Figures 6 and 7 engages the main bars 336 in a different manner to the embodiments described above.

The lifting device 310 has an eye or ring 314 in its upper portion 312, an intermediate portion 319 and a lower portion 3 16. The intermediate portion 3 19 comprises a laterally extending body portion 315, and a pair of downwardly extending legs 317 each having a transversely protruding foot 318 at its lower end. Each foot 318 has downwardly extending groove 330 and 332 let into its upper face. The device 310 sits astride a secondary bar 337 in the gridmesh pane! 338 while each of the legs 317 extends down between a common pair of main bars 336 and the bottom edge of one of the main bars engages into the grooves 330 and 332.

A small flat plate 346 is rotationally pivoted from a pin 348 on the main body 315 such that it forms a safety catch. The plate carries a notch 350 in its lower edge and the notch engages with the secondary bar 337 which the device 301 sits astride. The lifting device 301 does not need to be rotated to engage the lower edges of the bars in the gridmesh panel but instead a simple sideways movement is all that is required for the engagement. The lifting device 410 shown in Figures S and 9 has an upper portion 412, an intermediate portion 419 and a lower portion 416, and engages the gridmesh in a similar manner to the device 3.10 shown in Figures 6 and 7.

The intermediate portion 419 comprises a lateral ly extendi ng body portion 415, and a pair of downwardly extending legs 417. The body 415 and legs 417 sit astride a secondary bar 37 in the gridmesh panel 38 while each of the legs 417 extends down between a common pair of main bars.

At the lower portion 41 , each leg 417 has a transversely protruding foot 418 at its lower end. Eiach foot 418 has an upwardly extending toe portion 452 which forms a rectangular slot 454 between the leg 417 and toe 452. A main bar 36 of a gridmesh panel fits loosely into the slot 454 whereupon the latch arm 456 of a spring latch mechanism 457 mounted on respective legs 417 snaps outwards to retain the main bar 36 in the slot 454. A secondary bar 37 of the gridmesh extends through the arch 462 between the legs 417.

The square ring 414 in the upper portion 412 is connected to the intermediate portion 41 by a 360° swivel mechanism 458.

In a variation of the above described lifting device 410, a Towniey latch is provided on only one of the two legs 417. Such as embodiment is not preferred

The lifting device 510 shown in Figures 10 and 11 is similar in most respects to the lifting device 410 shown in Figures 8 and 9. However in device 510, each Towniey latch 457 is replaced by a pin 560 which passes through aligned holes 565 and 564 in each leg 517 and toe 552 respectively. The arch 562 formed between the legs 517 is a little lower than that in device 410 and is also more pointed.

In a variation of the above described lifting device 510, a retaining pin 560 is provided in only one of the two legs 517.

Referring to Figures 12a and 12b there is shown a lifting device 600 according to a further preferred embodiment of the present invention. The lifting device 600 comprises an upper portion 602 able to be lifted by a crane and a lower portion 604 able to support grid mesh 605 (see Figure 12b). In operation at least four lifting devices 600 are attached to the grid mesh 605 in a four point configuration and are lifted using tethers. Referring to Figure .12a, the lower portion 604 comprises a first foot portion 606 and a second foot portion 608. The first foot portion 606 and the second foot portion 608 extend either side of a shaft 610 and form a foot member 612 (the foot).

The foot member 612 is able to be inserted through a grid opening 614 of the sheet of grid mesh 605. As shown in Figure 12b the openings of the grid mesh 605 are of an elongate substantially rectangular shape provided by regularly space apart bars 616 of the grid mesh 605. The opening of the grid mesh 605 are provided in grid configuration.

In order to insert the foot member 612 through the grid opening 614, the foot member 612 is rotated to a first orientation aligned with the length 618 of the grid opening 614. Once received through the grid opening 614 the foot member 612 is rotated 90 degrees to a second orientation extending across the grid opening 614. hi this position beneath the grid mesh 605, in. the second orientation, the foot member 612 is unable to be withdrawn from the grid opening 614 through which the foot member 12 was inserted due to the two foot portions 606, 608 bearing against the grid mesh 605.

In the industrial walkway construction, grid mesh such as grid mesh 605 is commonly used to provide walkways. The applicant considers that the lifting device 600 provides an advantageous manner of lifting grid mesh of this type into position.

Referring to Figure 12a, the upper portion 602 includes a ring structure 620 at a first end 622 of the shank 610. The ring structure 620 is provided for being lifted by a crane. As shown the foot portions 606. 608 extend in opposite directions transversely from the shank 602 at an opposite end 624. As would be apparent the word opposite is used in the general sense and embraces substantially different directions. In this embodiment the foot portions are arranged to extend from the shank 610 at precisely 180 degrees to one another, being an exact mirror image.

Each of the two foot portions 606, 608 i nclude projecting elements 626 adapted to engage further grid openings 628 of the grid mesh 605 when in the second orientation.

The further grid openings 628 engaged by the projecting elements 626 are located in the vicinity of the grid opening 614. More particularly, the furthe grid openings 628 are transversely positioned either side of the grid opening 614 through which the foot .member 612 is inserted.

As shown in Figure 12a the projecting elements 626 are provided by a regular spacing of notches 630 in the upper edges 632 (surfaces) of the two foot portions 606, 608,

Notably the lifting device 10 includes a safety arrangement 634 for securing the projecting elements 626 in position preventing them from being removed from the further openings 628. The safety arrangement 634 is provided in the form of a retraining pin 636 and a passageway 638. The passagewa 638 extends through the projecting elements 626 to allow the retaining pin to be received therethrough with the grid mesh 605 secured in the notches 630 between the elements 626.

Advantageously in this embodiment the lifting device 600 is able to be used to lift one or two sheets of grid mesh 605 at a time. For this purpose there are provided a series 640 of passages, the passages comprising passage 638 and a passage 642 there below. The retaining pin 636 is secured in the passage 638 when lifting two sheets of grid mesh and is secured in passage 648 whe lifting one sheet of grid mesh. A pin 644 is provided for extending through an end 646 of the pin 644.

It would be apparent that the lifting device 600 provides a lower anchor portion that is able to be inserted through the grid opening 614, when in the first orientation (aligned in the elongate direction). The elements 626 of the anchor portion engage further grid openings 628 spaced apart from the first grid opening 614 when the anchor portion is rotated to the second orientation, after being inserted through the opening 614. The engagement with the further openings 628 prevents rotation of the anchor portion to the first orientation during lifting.

The elements 62 are provided as part of a foot member 612 that extends transversely to the shank 610. The foot member 612 has a number of recesses that define areas shaped to be received in the further openings 628. The areas are sequentially spaced apart by a number of recesses/notches 630. The recesses are provided in the form of pairs of notches for engaging corresponding bars of the grid mesh. Each foot portion 606, 608 provides two notches. After insertion the anchor portion is rotated from the first position by 90 degrees in the general plane of the grid mesh 605 to dispose the anchor portion in the second orientation. Advantageously the projecting elements 626 are able to accommodate multiple mesh panels stacked on top of the other.

A series of vertically extending passages is provided as part of a safety mechanism for securing a stack of grid mesh.

Referring to Figures 13a and 13b there is shown a lifting device 700 according to another embodiment. The lifting device 700 is similar to the lifting device 410 and provides a similar structure.

The lifting device 700 includes a handle 702 that provides a ready means for allowing the device 700 to be manually filled and gripped by a person. The handle 702 includes a deviation 704 in the form of portion 706 extending transversely away from the opening 708 of the hooks 710. This assists with limiting any impact to the shins of the person carrying the grid mesh. In other embodiments a deviation could of course be provided in the lifting arm 71 1 of each hook 710 to provide the handle 712 in a similar position relative to the opening 70S.

The lifter 700 is greater than 400mm tall. In this ease about ½ a meter tall. Thi provides advantageous reach. In some instance more than one sheet of grid mesh can be carried at any one time. Several lifting devices 700 may be used by different persons. As a result of the portion 706, the hand grip portion 71.2 is laterally offset from the opening 704, away from the hooks 710.

Referring to Figures 14a and 14b there is shown a lifting device 800 according to another embodiment. The lifting device is similar to the lifting device 410 and provides a similar structure. The lifting device 800 provides a singular plate 802 than operates on foot members 804. As before there is a downwardly extending groove 806 for engaging a first bar of a sheet of the grid mesh. As before, the legs 808 sit astride a second bar of the grid mesh where the second bar is aligned transversely to the first bar. The plate 802 is fixed in position using a spring pin 810. The use of the singular plate 802 provides advantageous safety.

Referring to Figures 15a and 15b there is shown a lifting device 900 according to yet another embodiment. As shown the spacing 901 between the leg portions 902 is about 20mm and the height of the device is about 200mm. The lifting ring 904 is centrally positioned above the two slots 906, This assists with aligning forces applied to the lifting ring and the two hook shaped lifting members 908. The width of each slot is about 10mm and the depth of each slot is about 60mm.

Referring to Figures 1 a and 16b there is shown a rotation type lifting device 910. The base of the rotation type lifting member 910 is greater than 50mm in width 912, and the thickness 914 is about 10mm. The height of the device is about 200mm. Two slots 9 8 are provide either side of a shank 916. The slots are provided by corresponding hook portions 908 that are of a width 942 sized to fit within a grid mesh opening.

Referring to Figure 17 there is shown a rotation type lifting device 920 for manual lifting of gridmesh according to another preferred embodiment of the present invention. The rotation type lifting device 920 over 650mm tall and includes a lifting handle 922. The lifting handle 922 includes a gripping portion wide enough to be gripped by hand and facilitate lifting of an end of a grid mesh panel. The grid mesh includes a biasing arrangement 924 in the form of a spring 926 and a biasing element 928. An abutment 930, is provided for forcing the spring to push the biasing element 928 downwardly. The biasing element 928 includes a number of notches 932 for engaging bars of the gridmesh. The notches are spaced along the biasing element 928 and are arranged to face corresponding notches of a foot 934.

Referring to Figures 18a and 18b there is shown a double hook type lifting device 936 according to another preferred embodiment of the present invention. The handle 938 is offset away rearward from the slot 937 of the hook portions 940, away from the terminating ends 944 of the hook portions.

The handle 938 includes a shaft 960 having a threaded end that is threaded into a body 965. The body 965 includes a rearward deviation 935. The upper portion 967 of the body 965 provides a threaded element 969 for selective attachment. An opening 945 receives a grub screw to secure the shaft in position.

Figures 19 to 22 illustrate a lifting device 946 according to yet another preferred embodiment. The lifting device includes an advantageous safety catch 948, The safety catch 948 is bent from a piece of sheet metal 950. The sheet metal 950 includes two tabs

952 for providing a gripping portion either side of safety plate 948. The tabs 952 allow a workman to open the safety catch 948 with a pincer-type grip. Two holes 954 are provided for engaging flange portions on the sides of the body of the lifting device. Two bend lines 956 are provided to position the holes 954 facing the sides of the body of the lifting device. Two bend lines 958 are provided to position the tabs extending in the direction of length of the safety catch 948.

The safety catch 948 comprises a singular plate that extends across each groove of the pair of legs; and which extends across the bars that the legs of the lifting device sit astride.

By extending across the bars that the lifting device sits astride and by comprising a single plate an advantageous safety catch 948 is provided. The plate comprises a singular plate that is bent to provide flanges for being pivotaliy mounted to the sides of the body of the lifting device.

The plate is biased towards the position in which the safety catch extends across each groove. The safety catch 948 bears against the terminal ends of the hook portions. A ring 9 1 is secured to the upper end of the body of the device using a bolt. Various biasing arrangements could be used with spring fixed on the front face of the lifting device or otherwise.

Referring to Figures 21 a and 21 b, the lifting device 946 includes a body 947 having an upper portion 949 and a lower portion 951 , The upper portion 949 includes a connection portion 960 and is provided for being lifted. The lower portion 951. provides a pair of legs

953 separated by a slot 955. Each leg 953 provides a foot member 957 having a downwardly extending groove 959 for engaging a first bar of a sheet of grid mesh. As previously described, the legs astride a single second bar of grid mesh with the second bar being aligned transversely to the first bar. Referring to Figure 21 a, the connection portion 960 provides an enlarged end for fixing a lifting element thereto. In the present embodiment the lifting element comprises the lifting ring 961. The connection portion 960 provides and end of the body 947 with an upwardly facing threaded opening 962 for receiving a shank of a bolt 963. The threaded opening 962 provides a threaded hole that is able to receive a threaded fastener.

The connection portion 960 allows the lifting ring 961 to be positioned at an upper position relative to the body 947. The lifting ring 961 ring is able to be mounted by threading the bolt 963 through a lateral opening 973 in the lifting ring 961, extending transversely relative to the primary opening 966, into the opening 962 with the bolt 963 providing a swivel point for the ring 961.

The connection portion 960 provides an enlarged portion 967 that accommodates the opening 962. The connection portion 960 provides a relatively flat upwardly facing surface 968 surrounding the opening 962.

Mount points 969 provide a pivot point for the safety catch which is biased to a closed position using a spring.

Figures 22a and 22b show how the lifting ring can be advantageously replaced with a manual lifting handle having a threaded end. This is achieved by removing the bolt 963 and threading the end of the handle into the opening 962. The lifting device 963 advantageously allows for selective co nection of a lifting ring or a shaft type lifting handle.

A safety catch might not be present for manual lifting. In this embodiment the handle has a threaded end for threaded into the opening. In other embodiments the handle is an integral part of the body and cannot be removed thereform.

As would be apparent, with the safety catch 948, bearing downwardly on the safety catch 948 allows: the hook portions to pushed be through grid openings, of a sheet of grid mesh; two foot portions to be engaged with a lower surface of one of the bars of the gridmesh; and lifting of the panel by means of the lifting device so engaged. In operation the bar of the gridmesh applies an opening force to the safety catch which pivots to provide access to the slots. Once received the safety catch returns to its original position to relatively securely hold the first bar. Figures 23 and 24 illustrate a further preferred embodiment of the present invention. In the embodiment an elongate handle extends to space a hand grip portion of the handle away from each downwardly extending groove in a manner assisting with limi ing any impact to the shins of a person carr ing the grid mesh. The elongate handle is at least 450 long to provide the lifting device with a length of at least 650mm. Bolts are able to be threaded through the U-shaped arms of the leg portions to secure the grid mesh as shown.

The front amis of the legs may al low for a shackle type join as shown in Figure 24, The u- shaped portions include an opening extending therethrough. They have a threaded opening on the rear arm of each leg as shown. This could of course be reversed with the shackle extending from the other side. Figure 24 shows how a handle may receive an end of the body of a lifting device. Various manners of connecting a handle and securing the grid mesh as possible.

Whilst the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions may be introduced into the constnictions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the invention.

It will be also understood that where the word "comprise^'", and variations such as "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

There is no intention to limit the present invention to the specific embodiments shown in the drawings. The present invention is to be construed beneficially to the applicant and the invention given its full scope.

Claims

TH E CLA I MS D E FI N ING TH E I N V E NTI ON A RE AS FOLLOWS :

1. A lifting device comprising: an upper portion that is able to be lifted and a lower portion comprising two foot portions; the foot portions extending in opposite directions and providing a foot; the foot being able to be inserted through a grid opening of a sheet of grid mesh between the bars of the grid mesh, when the foot is rotated to a first orientation, and then be rotated to a second orientation in which the foot is unable to be withdrawn from the grid opening through which the foot was inserted, due to the foot portions of the foot extending in opposite directions to each bear against the grid mesh from below.

2. A lifting device as claimed in claim 1 wherein the upper portion comprises a shank having a ring stmcture at a first end of the shank, the ring structure able to be lifted by a crane; the two foot portions extend in opposite directions transversely from the shank; and the foot portions are provided at an opposite end of the shank to the ring structure.

3. A lifting device as claimed in claim 1 or 2 wherein the ring and shank are centrally located between the foot portions,

4. A lifting device as claimed in claim 1 wherein the upper portion comprises a shank having a handle at a first end of the shank, the handle able to be lifted by a workman; the two foot portions extend in opposite directions transversely from the shank; and the foot portions are provided at an opposite end of the shank to the handle.

5. A lifting device as claimed in any one of claims f to 4 wherein the foot portions include elements adapted to engage further grid openings of the grid mesh when in the second orientation, the further grid openings engaged by the elements being located in the vicinit of the grid opening through which the foot member is able to be inserted.

6. A lifting device as claimed in any one of claims 1 to 5 wherein the elements are pro vided by a regular spacing of recesses in the upper surface of the foot member.

7. A lifting device as claimed .in any one of claims 1 to 6 including a biasing arrangement for biasing the gridmesh downwardly to assist with holding the gridmesh in position on the foot.

8. A lifting device as claimed in claim 7 wherein the biasing arrangement includes a spring and a holding element; the spring for urging the holding element downwardly to push the gridmesh towards the foot.

9. A lifting device as claimed in claim 8 wherein the holding element includes a number of notches for engaging the grid mesh when urging the grid mesh towards the foot; the notches being provided in the surface of the biasing element feeing the foot; and the notches are aligned with corresponding notches provided in the foot.

10. A lifting device comprising: a shank member having a lifting portion and an anchor portion, the anchor portion being able to be inserted through a first grid opening of a sheet of grid mesh, when in a first orientation; the anchor portion comprising at least two elements able to engage further grid openings spaced apart from the first grid opening when the anchor portion is rotated to a second orientation, once inserted througli the first opening, the engagement provided by the at least two elements with the further openings, able to prevent rotation of the anchor portion to the first orientation during lifting.

1.1. A lifting device as claimed in claim 10 wherein the two elements comprise two support members that extend transversely, in opposite directions, from the lifting portion, the support members having a number of recesses between upper areas, the upper areas being shaped to be received in the further openings.

12. A lifting device as claimed in claim 1 1 wherein each support member includes the recesses as a pair of notches, each pair of notches for engaging two bars of a grid mesh panel when the anchor portion is positioned for lifting is in the second orientation underneath the grid mesh panel.

1.3. A lifting device as claimed in claim .10, 1 1 or 12 wherein rotating the anchor portion from the first position by 90 degrees in the general plane of the grid mesh disposes the anchor portion in the second position.

14. A lifting device as claimed in any one of claims 10 to 13 wherein the lifting device includes a safety arrangement for securing the at least two elements in position and preventing them from being removed from the further openings.

15. A lifting device as claimed in claim 1.4 including a safety arrangement provided in the form of a retaining pin able to secure the at least two elements in position and prevent them from being removed from the further openings.

16. A lifting device comprising: a body having an upper portion and a lower portion; the upper portion for being lifted; and the lower portion providing a pair of legs each having a foot member having a downwardly extending groove for engaging a first bar of a sheet of grid mesh; the legs for sitting astride at least one other bar of the grid mesh, the or each other bar being aligned transversely to the first bar.

17. A lifting device as claimed in claim 16 wherein the legs are configured to sit astride a single other bar of the grid mesh; and the upper portion includes a connection portion, the connection portion for fixing a lifting element thereto, the connection portion providing an opening for receiving a shank.

1.8. A lifting element as claimed in claim 16 or 17 wherein the opening faces upwardly to allow the lifting element to be positioned at an upper position; the connection portion allowing for selecti ve connection of a lifting ring or a shaft type li fting handle.

19. A lifting device as claimed in claim 16, 17 or 18 wherein the connection portion provides a threaded aperture for receiving a threaded shank of a bolt.

20. A lifting device as claimed in any one of claims 16 to 1 including a ring that is adapted to be mounted with the use of a bolt threaded into the opening, the bolt providing a swivel point for the ring.

21. A lifting dev ice as claimed in any one of claims 16 to 19 including an elongate handle for being threaded into the opening.

22. A lifting device as claimed in claim 21 wherein the elongate handle extends to space a hand grip portion of the handle away from each groove of each foot member in a manner assisting with limiting any impact to the shins of a person carrying the grid mesh.

23. A lifting device as claimed in. claim 21 or 22 wherein the elongate handle is at least 400mm long to provide the lifting device with a length of at least 600mm.

24. A lifting device as claimed in wherein the upper portion provides an enlarged head portion.

25. A li fting device as claimed in any one of claims 16 to 24 wherein the pair of legs of the lower portion are spaced apart by 10mm.

26. A lifting device as claimed in claim in any one of claims 16 to 25 wherein the pair of legs of the lower portion are spaced apart by 10mm or more.

27. A li fting device as claimed in any one of claims 16 to 26 wherein the pair of legs of the lower portion are spaced apart by 20 mm or more.

28. A lifting device claimed in any one of claims 16 to 27 wherein the pair of legs of the lower portion are spaced apart to span a grid mesh opening.

29. A lifting device as claimed in any one of claims 1.6 to 28 wherein each downwardly extending groove is at least 40mm long.

30. A lifting device as claimed in any one of claims 16 to 29 wherein each downwardly extending groove is configured to neatly support the depth of the first bar.

31. A lifting device as claimed in an one of claims 16 to 31 wherein each downwardly extending groove is about 10mm wide.

32. A lifting device as claimed in any one of claims 16 to 31 including a safety catch for assisting with ensuring that the lifting device does not become separated from the gridmesh; wherein in a secured condition; the safety catch extending across the second bar that the legs of the lifting device sit aside; and the safety catch extending across each groove of the pair of legs.

33. A lifting device as claimed in claim 32 wherein the safety catch comprises a singular plate that is bent to provide flanges for being pivotally mounted to the sides of the body of the lifting device.

34. A lifting device as claimed in any one of claims 1 to 33 wherein the legs of the tower portion are provided as hook portions; the hook portions able to be inserted through corresponding grid openings of the sheet of grid mesh and, without rotation, be moved sideways towards the first bar and be unable to be withdrawn from the grid opening by each foot member bearing against the first bar,

35. A method of lifting a panel of grid mesh, said method comprising: interesting a foot of a lifting device through grid openings of a sheet of grid mesh, engaging two foot portions with a lower surface of one of the bars of the gridmesh: and lifting the panel by means of the lifting device so engaged.

36. A method as claimed in claim 35 wherein engaging the two foot portions comprises, without rotation, moving the lifting device downwardly through the grid openings, sideways towards the first bar and then upwardly to engage the first bar so as to be unable to be withdrawn from the grid opening by each foot member bearing against the first bar,

37. A method of using a crane to lift a panel of a walkway gridmesh on a building site, said gridmesh comprising a plurality of interlinked bar's with apertures between the bars, and said method comprising: - inserting a foot of a lifting device downwards between a pair of adjacent said bars;

- engaging said foot with a lower surface of at least one of said pair of bars; and

- lifting the panel by means of the lifting device so engaged; wherein:

- said lifting device comprises an upper portion comprising a ring to which the crane is attached in use; and

- said oot of the lifting device comprises two foot portions separated from each other and which engage the panel beneath said lower surface of at least one of said pair of bars.

38. A method according to claim 37 wherein said gridmesh comprises metal bars welded together to form a rectilineal" grid having:

- a fi rst array of said bars paral lel to and spaced from each other, and

- a second array of said bars parallel to and spaced from each other, and aligned transversely to the bars in said first array.

39. A method according to claim 38 wherein:

- said lifting device comprises a shank extending between said ring and said foot and extending between said pair of bars,

- said foot portions extend in opposite directions from said shank, and

- said lifting device is rotated after insertion between said pair of bars, such that said shank extends between said pair of bars, and said engagement of the foot portions with the panel is such that each said foot portion engages a different one of said pair of bars.

40. A method according to claim 39 wherein a flange extends from said shank immediately below said eye.

41. A method according to claim 40 wherem: said lifting device comprises a pair of spaced apart legs which extend down between said pair of bars

- each said leg has a respective foot portion extending laterally therefrom; and

- each said foot portion engages beneath the same one of said pair of bars.

42. A method according to claim 41 wherein said lifting device has a bifurcated member which engages t he panel astride one of the bars in sai d second array.

43. A method according to any one of the previous claims 37 to 42 wherein said foot portions include recesses on their upper surfaces into which said lower surface of said at least one bar is located.

44. A lifting device comprising an upper portion and a lower portion; the upper portion including a shank; the lower portion comprising two foot portions providing a foot member; the two foot portion extending in opposite directions transversely from the shank to provide a foot member; the foot member being able to be inserted through a grid opening of a sheet of grid mesh between the bars of the grid mesh, when the foot member is rotated to a first orientation, and then be rotated to a second orientation in which the foot member is unable to be withdrawn from the grid opening through which the foot member was inserted due to the two foot portions bearing against the grid mesh

45. A lifting device as claimed in claim 44 wherein the upper portion comprises a shank ha ving a ring structure at a first end of the shank, the ring structure able to be lifted by a crane; the foot portions being provided at an opposite end of the shank to the ring structure for engaging two adjacent bars of the gridmesh.

46. A lifting device as claimed in claim 44 or 45 wherein the foot portions include elements adapted to engage further grid openings of the grid mesh when in the second orientation, the further grid openings engaged by the elements being located in the vicinity of the grid opening through which the foot member is able to be inserted.

47. A lifting device comprising a shank member having a lifting portion and an anchor portion, the anchor portion being able to be inserted tlirough a first grid opening of a sheet of grid mesh, when i a first orientation; the anchor portion comprising at least two elements able to engage further grid openings spaced either side of the first grid opening when the anchor portion is rotated to a second orientation, once inserted through the first opening, the engagement provide by the at least two elements with the further openings able to prevent rotation of the anchor portion to the first orientation during lifting.

48. A method of lifting a panel of a walkway gridmesh on a building site, said gridmesh comprising a plurality of interlinked bars with apertures between the bars, and said method comprising: inserting a foot of a lifting device downwards between a pair of adjacent said bars, with the lifting device in a first orientation; rotating the lifting device to a second orientation and engaging said foot with a lower surface of at least one of said pair of bars; and lifting the panel by means of the lifting device so engaged; wherein: said lifting device comprises an upper portion comprising a shank; and said foot of the lifting device comprises two foot portions extending in opposite directions from the shank and separated from each other and which engage the panel beneath the bars.

49. A lifting device comprising; a body having an upper portion and a lower portion; the upper portion for being lifted; the lower portion providi ng a pair of legs each having a foot member having a downwardly extending groove for engaging a first bar of a sheet of grid mesh; the legs for sitting astride a second bar of the grid mesh, the second bar being aligned transversely to the first bar; and a connection portion allowing for selective connection of a lifting ring or a shaft type lifting handle.