AU2016203248A1 - Apparatus operable with a building-site lifting device, for controlling the orientation of an elongate building component - Google Patents

Abstract

Apparatus by which an elongate building component is mountable on a lifting device for raising the elongate component to an installation position, is adapted for engaging and holding the elongate component in relation to the lifting device. The apparatus further is operable to enable the elongate component, while being raised, to adjust from an orientation in which the longitudinal extent of the component is predominantly horizontally extending to an orientation in which the longitudinal extent is predominantly upwardly extending. (N4 r-(N C (N ~ f /4r-4 LL -

Description

APPARATUS OPERABLE WITH A BUILDING-SITE LIFTING DEVICE, FOR CONTROLLING THE ORIENTATION OF AN ELONGATE BUILDING

COMPONENT

FIELD OF THE INVENTION

[001] This invention relates to an apparatus, mountable on a lifting device, and operable to facilitate raising of an elongate building component to a required position in a manner facilitating presentation of the component in an orientation required for installation.

BACKGROUND TO THE INVENTION

[002] At many building sites, for both single and multi-storey buildings, it is necessary to raise components of various building materials from a support surface at a supply level, such as the ground, to a level at which they are to be installed. In many instances the operation is relatively simple, as the orientation of the components does not need to be changed from that in which they are provided at the supply level. However, in some instances with elongate components, it is required to change the orientation of the components from that in which they are provided at the supply level, in which the longitudinal extent typically is somewhat horizontally disposed, to an orientation required for installation of the component in which the longitudinal extent is upwardly disposed, such as substantially vertically. Components for which this change may be required can include beams, posts or columns of timber or of a metal, such as steel or aluminium, such as to comprise a part of a structural framework of a building. Alternatively, the components may comprise long lengths of panels or sheeting, of metal, plastics, glass or other materials, to comprise for example a fascia or wall cladding component of the building. Frequently an elevated work platform (EWP) is used for lifting such elongate components. Particularly where the orientation of the components is to be changed, many work sites rely on the on-site availability of sufficient people to assist on and around the EWP to enable a component to be reoriented and held as the EWP is operated to raise the component. The component may be held in relation to the rising EWP either manually or by vice grips. Alternatively, the component may be secured to the EWP by fitting a shackle through a hole in the component and providing a chain connector between the shackle and the EWP.

[003] Such lifting arrangements are relatively labour-intensive and not without danger. Also, the arrangements can complicate the task of ensuring that a component, when raised to a required installation position, is substantially in the orientation the component is to occupy when installed. The present invention is directed to providing an apparatus that is mountable on a lifting device, such as an elevated work platform, and is operable for facilitating raising an elongate component of building material to an installation position substantially in an orientation required for the component when installed.

BROAD SUMMARY OF THE INVENTION

[004] In broad terms, the present invention relates to an apparatus by which an elongate building component is mountable on a lifting device for raising the elongate component to an installation position. The apparatus is adapted for engaging and holding the elongate component in relation to the lifting device and is operable to enable the elongate component, while being raised, to adjust from an orientation in which the longitudinal extent of the component is predominantly horizontally extending to an orientation in which the longitudinal extent is predominantly upwardly extending. The arrangement most conveniently is such that, with the lifting device positioned adjacent to a building structure at or below a location at which the elongate component is to be installed, the apparatus enables the elongate component to adjust so that, when the component is fully raised by the lifting device, the component is substantially positioned and orientated for installation as part of the building structure, substantially without a need for reorienting the component.

[005] The apparatus of the invention may be mountable on the lifting device in a number of different ways, depending in part on the type of lifting device with which the device is to be employed. Several forms of lifting device can be used, and include those known as personnel lifts, vertical masts, boom lifts, articulated boom lifts, inventory pickers, material handlers, scissor lifts, telehandlers, articulating lifts and telescopic lifts. In each case, the lifting device has a platform or similar structure that can be raised and lowered, as required, on which personnel can stand. It is in relation to such platform or similar structure that the apparatus can be mounted.

[006] In one form the apparatus of the invention includes a securement member that is adapted to be secured to the lifting device, such on the platform or similar structure of the device, by bolts or other fastening members able to be engaged with the lifting device. The securement member may comprise a body portion that can be engaged with the platform, or another appropriate part of the lifting device, by the bolts or other fastening members. In that one form the apparatus has an engagement member by which the device is adapted for engaging and holding the elongate component, with the securement member and the engagement member being rotatable relative to each other about a swivel axis.

[007] The apparatus of the invention may be adapted for engaging and holding the elongate component in a variety of different ways. For this purpose, the engagement member of the device may be able to encircle and grip the elongate component, such adjacent to, or towards, one end of the component. The engagement member may include a backing part able to bear against the elongate component and a holding part for holding the component securely against the backing part. Where the engagement member is in the nature of a beam, post or column, the backing part may comprise a plate, while the holding part may comprise a chain or strap fixed at one end at or adjacent to a side of the plate and able to be secured at or adjacent to an opposite side of the plate after being drawn around the component. With such an arrangement using a chain or strap, there is a risk that the elongate member could slide out of engagement in the engagement member as the orientation of the component changes so that the longitudinal extent becomes sufficiently upright. To prevent the component from being able to slide out, the arrangement can necessitate the existence of a pin or other formation projecting from the elongate member so as to be engaged by the chain or strap. However, instead of a chain or strap, an alternative arrangement has a stiff or rigid cover hinged at or adjacent to one side of the plate and able to be rotated and clamped at or adjacent to the opposite side of the plate and thereby firmly grip the component against the plate so as to safeguard against the component being able to slide out of engagement in the engagement member.

[008] Where the elongate component is in the form of a panel or sheeting, the engagement member of the apparatus may be somewhat analogous to the clamping form comprising a plate to which a stiff or rigid cover is clamped for firmly gripping a component in the form of a beam, post or column. However, for a component in the form of a panel or sheeting, the plate and cover of the engagement member need to be able to span the major dimension or width of the component perpendicular to the longitudinal extent, while the component and the cover can be relatively thin. However, with some sheeting, such as profiled sheeting, the sheeting can have a depth that, even if minor relative to the width, is substantial and necessitates the plate and/or cover being able to accommodate the depth. With a plate of the engagement member positioned against one of oppositely facing surfaces of the component, from one to the other of opposite sides of the component, the cover of the engagement member is able to be moved so as to extend from the one side to be positioned similarly against and across the other of those surfaces, and then clamped to the plate adjacent to the other side of the component.

[009] As with an elongate component in the form of a beam, post or column, a component in the form of a panel or sheeting can tend to slide out of engagement in the engagement member. There can be a lesser tendency for this with a panel or sheeting, given the greater surface-to-surface contact between the component and each of the plate and cover of the engagement member. Also, for a component of either form, the tendance for it to slide out of engagement in the engagement member preferably is reduced by provision of a facing of a material having a high coefficient of friction over surfaces of the engagement member that are to bear against the component.

[010] Other forms of engagement member can be used. For example, the engagement member may be in the form of a clamp mechanism operable to grip and release the component, as required. In one convenient arrangement the engagement member may be a pneumatically or hydraulically operated clamp mechanism.

[011 ] In each of the forms discussed above the engagement member is of a form able to engage an elongate component by contacting, such as to grip, oppositely facing surfaces of the component. This can be undesirable for those components having easily marred surfaces or surface finishes, and it also can be undesirable for components made of brittle or fragile materials such as glass and some plastics materials. Particularly in these cases it is preferable for an engagement member of a different type to be used. A first form of engagement member of a different type comprises a vacuum lifter of a type suitable for carrying sheets of glazing. An engagement member of this type has at least one suction cup mounted on a backing plate, or a common or respective backing plate where the engagement member has at least two suction cups. The arrangement is such that, with the at least one suction cup held firmly against one of oppositely facing surfaces of the elongate component, the engagement member is able to firmly engage, or adhere to, the one surface by generation of a substantial vacuum or reduction in pressure between the interior of the or each cup and the one surface. The vacuum may be generated by the action of a hand pump operable to generate pressure between the exterior of the cup and the backing plate and thereby force the cup towards the one surface to displace air from the interior of the cup; or by actuation of a mechanical lever mechanism operable to force the cup against the surface of the component to displace air from within the cup; or by connecting the interior of the cup to a vacuum source by which air can be drawn from within the cup; in each case to attain the required substantial vacuum.

[012] A second form of engagement member comprises a backing plate on which is mounted a coil of insulated wire formed around an iron core, with the ends of the wire connectable to a direct current power source via a current controller, enabling the engagement member to operate as an electromagnet for use with elongate components comprising ferromagnetic panels or sheeting.

[013] As detailed above, the securement member and the engagement member are rotatable relative to each other about a swivel or pivot axis. To enable this the securement member and the engagement member are inter-connected in a manner enabling the relative swivelling or pivoting. In one arrangement the securement and engagement members are inter-connected by an axle having an axis co-incident with the swivel or pivot axis. The arrangement is such that, with the securement member mounted on and fixed relative to the lifting device, the engagement member is able to swivel or pivot on the swivel or pivot axis through a required angle relative to the securement member. The swivelling or pivoting most preferably is reversible and, for many purposes, the angle may be from about 85° to 95°, such as substantially about 90°. However, the purpose of the engagement member swivelling or pivoting is to enable an elongate component, while being raised by the lifting device, to adjust from an orientation in which the longitudinal extent of the component is predominantly horizontal to an orientation in which that extent is predominantly upwardly extending. Thus, it is appropriate for the component to swing, or be swung, substantially parallel to an upwardly extending plane, such as a substantially vertical plane, that is substantially perpendicular to the swivel or pivot axis and the axle. The axis and axle predominantly extend horizontally, and the axis and axle may be substantially horizontal.

[014] In use of the apparatus of the invention, the engagement member may swivel or pivot relative to the securement member as a consequence of the effect of gravity acting against the elongate component being raised. That is, the weight of the component may cause the component to swivel or pivot so as to move below the engagement member as the component is raised. Thus, if the component is lifted free of a support surface at the supply level on which it initially rested, with the longitudinal extent of the component disposed horizontally, the component can be suspended from the engagement member with that longitudinal extent upwardly disposed. The extent to which the longitudinal extent departs from vertical can vary due to any off-centre engagement of the component by the engagement member and/or variation in the cross-section of the component along the longitudinal extent of the component. However, for a component that is uniform along the longitudinal extent and that is appropriately engaged by and suspended from the engagement member, the longitudinal extent of the component can be substantially vertical, as required in many instances for installation of the component.

[015] For swivelling or pivoting of the engagement member relative to the securement member, the engagement member may be free to swivel or pivot on the swivel axis and, hence, free to respond to the weight of the elongate component, with an end of the component remote from the apparatus at least initially being drawn across the support surface at the supply level. As the elongate component is raised sufficiently so as to swivel or pivot freely under gravity, the component may initially move past a position required for installation of the component, and then move back and a oscillate until arrested. However, rather than enable such oscillation, the engagement member may be retarded in its swivelling or pivoting, rather than free to swivel or pivot, so that swivelling or pivoting occurs only through a required angle, such as about 90°. In one arrangement, swivelling or pivoting may be controlled by provision of a ratchet device. In another arrangement, a stop may be provided to limit the extent of swivelling or pivoting to a pre-determined limit.

[016] With profiled metal sheeting, it is appropriate in many instances for the ribs or other longitudinal formations to be disposed vertically in the sheeting when installed, such a cladding for a wall. However, in some instances architectural or aesthetic considerations require the ribs or other formations, while extending upwardly, are inclined at an angle to the vertical. Control over swivelling or pivoting of the sheeting as it is raised using the apparatus of the invention can, such as detailed above, can facilitate orientating the panel for such inclined installation.

BROAD DESCRIPTION OF THE DRAWINGS

[017] Figure 1 is a perspective view of one form of apparatus according the present invention; [018] Figures 2 and 3 show respective perspective views of one component of the apparatus of Figure 1 in the course of installation on a lifting device; [019] Figure 4 is a perspective view of the apparatus or Figure 1 as fully installed on the lifting device in readiness for use; [020] Figure 5 shows part of the apparatus shown in Figure 4, but on an enlarged scale; [021] Figure 6 shows one end of an elongate building component secured in relation to the apparatus of Figure 1, in readiness for re-orienting the component from a disposition in which its longitudinal extent is horizontally disposed to a disposition in which that extant is disposed upwardly; [022] Figure 7 shows the commencement of the re-orientation; [023] Figure 8 shows enlarged detail of the apparatus of Figure 1, in an in-use condition, but in the absence of an elongate component; and [024] Figure 9 shows an advanced stage of re-orientation, short of full raising of the component.

[025] Figures 1 to 8 show one form of apparatus 10 suitable for use in reorienting an elongate building component 12, illustrated by profiled metal sheeting in Figures 6 and 7. As shown in Figures 2 to 7, the apparatus is mountable on a lifting device 14 for raising the component 12 to an installation position, the device 14 by way of example comprising a Compact 10DX model of scissor lift available from the Haulotte Group. The apparatus 10 is adapted for engaging and holding the component 12 in relation to the lifting device 14 and is operable to raise the component 12 and to enable the component 12, while being raised, to adjust from an orientation in which the longitudinal extent of component 12 is predominantly horizontally extending to an orientation in which the longitudinal extent is predominantly upwardly extending. The arrangement is such that, with the lifting device 14 positioned adjacent to a building structure at, or below, a location at which the component 12 is to be installed, the apparatus 10 enables the component to adjust so that, when fully raised by the lifting device 14, the component 12 is substantially positioned and orientated as required, such as for installation as part of the building structure, such as substantially without a need for reorienting the component 12.

[026] The apparatus 10 includes a securement member 16 that is adapted to be secured to the lifting devicel 4, such as on the platform 18 or similar structure of device 14, by bolts or other fastening members. As shown in Figures 1 to 3, the securement member 16 comprises a body portion that can be engaged with the platform 18, while an engagement member 20 by which the apparatus 10 is adapted for engaging and holding the component 12, can be mounted on member 16. The securement member 16 and the engagement member 20 are able to be interconnected for relative rotation on a swivel or pivot axis. In the arrangement illustrated, the interconnection is enabled by a projecting axle rod 22 of engagement member 20 being mounted for rotation within a bore 24 defined by securement member 16, with the longitudinal axis X-X of rod 22 providing the swivel or pivot axis. With the apparatus 10 secured on the lifting device 14, the axis X-X extends at least somewhat horizontally, such as to be substantially horizontally disposed, and substantially perpendicular to a plane in which component 12 is able to adjust as it is being raised.

[027] The engagement member 16 includes an elongate PFC-(parallel flange channel) steel bar 26 that, in use, normally is horizontally disposed. The bar 26 is supportable at what is a rear end on a first support 28 comprising a first short PFC steel bar, while the other, forward end of bar 26 projects beyond and is supportable on a second short PFC steel support 29. Each of supports 28 and 29 is welded to bar 26. Within a channel 26a defined by bar 26, a longitudinally spaced pair of transverse plates 26b are secured by welding in the forward end section of bar 26. Aligned holes 26c in plates 26b are able to accommodate rod 22 for rotation in securement member 16 and to enable swivelling or pivoting of engagement member 20, relative to securement member 16.

[028] As shown in Figures 2 and 3, securement member 16 can be secured to platform 18 of lifting device 14. For this, member 16 is positioned on platform 18, with bar 26 perpendicular to a side edge 18a of platform 18 and the forward support 29 at or closely adjacent to edge 18a, so that the forward end of bar 26 projects beyond the platform 18. The securement member 16 is retained in position by bolts 30 extending up through the platform, through the lower flange of each of supports 28 and 29, and retained by the provision of bolts 31.

[029] The engagement member 20 includes an elongate steel bar 32 of L-section that has first and second flanges 34 and 35, and a length greater than the transverse width of the profiled metal sheeting comprising component 12. One end of axle rod 22 is welded to a midpoint on the inner surface 34a of the first flange 34 of bar 32 while, with rod 22 rotatable in the holes 26c of securement member 16, the outer surface 34b of flange 34 is positioned for engagement with component 12. Adjacent to each end of bar 32, a respecting steel block 36 is welded onto and stands proud of surface 34b, with the main part of the length of surface 34b and each of blocks 36 covered with a protective cover 37 of felt, rubber or polymeric foam. The arrangement is such that bar 32 is able to be presented across the width of the sheeting comprising component 12 to bring the protective cover into contact with one of the opposite surfaces of component 20, with each block 36 in line with and being received against the base of a trough between respective pairs of successive ribs 20a of component 20. The component 12 then is can be held firmly by a holding bar 38 of engagement member 20 being locked across the other major surface of component 12.

[030] The holding bar 38 comprises a square section tubular bar that is secured at a one end to a first end of flange 34, by a bolt 40 that passes through bar 38 and is welded to the surface 34b of flange 34. The arrangement is such that bar 38 is able to swing in a plane substantially parallel to surface 34b, so is able to be movable between an engagement position in which bar 38 extends over the length of surface 34b, from the first end, to the second end, of bar 32 and a remote position in which bar 38 projects directly away from the first end, away from the second, of bar 34. With bar 38 in the engagement position, the arrangement can be secured to enable a component to be firmly engaged. For this, the bar 32 carries a bracket 42 adjacent to the second end of flange 34, with the bracket 42 defining a bight 42a that opens laterally to one side of bar 32 and into which bar 38 is received when in the engagement position. Adjacent to the bracket 42 one end of a chain 44 is secured by welding to bar 32 and, with bar 38 received into the bight 42a and into the engagement position, chain 44 is able to wrap around bars 32 and 38 and hold bar 38 by a link 44a of chain 44 locating in a slot 42a cut is an edge of bracket 42 spaced from flange 34b.

[031] For use of the invention, the apparatus 10 first is installed in the lifting device 14, as outlined above. For this, and with the device 14 positioned adjacent to a first end of the component 12, that is, the end to be the upper end of a component 12 when raised, the device 14 is lowered as shown in Figure 6. The engagement member 20 then is engaged with that end of the component 12. For such engagement the component 12 is held in a raised position in which it initially rests one of its opposed longitudinal side edges, and the first end of the component then is manually lifted laterally as shown in Figure 6. With the holding bar 38 of member 20 in its remote position and the bar 32 of member 20 suitably inclined, as seen in Figure 4, an end portion of the component 12 is positioned across the surface 34b of flange 34 of bar 32, against the protective cover 37, with each block 36 aligned with the base of a respective trough between a respective pair of ribs 20a. The positioning of the first end of component 12 is such that a sufficient length of the component projects beyond bar 32. The holding bar 38 then is swung around bolt 40 to the engagement position shown on Figure 6, in which position the end of bar 38 is received laterally into, to projects longitudinally through the bight 42a defined by bracket 42. The bar 38 then is retained, so the component is securely gripped between bar 38 and bar 32, by the chain 44 being wrapped around the projecting end of bar 38, and location of a link of chain 44 edgewise in the slot 42a in bracket 42.

[032] After the first end of component 20 has been secured between the bars 32 and 38 of engagement member 20, the lifting device is able to be actuated so platform 18 is raised by extending the scissor arms 14a providing the scissor-type action of lifting device 14. As that action raises platform 18, the mounting of the securement member 16 on platform18 causes the apparatus 10 as a whole to be raised, with component 12 being raised endwise with the first end leading. As the scissors arms 14a continue to extend, the influence of gravity acts to draw the centre of mass of the component 12 laterally towards a position below the axis X-X by the component 12 moving in a plane perpendicular to axis X-X. The arrangement is such that, if device 14 is able to extend sufficiently, the component 12 will move to and beyond the position shown in Figure 9, such as to be suspended below apparatus 10 with the centre of gravity on or adjacent to a position below axis X-X. This movement of component 12 is enabled by engagement member 20 swivelling or pivoting arcuately relative to securement member 16 on an axis substantially co-incident with axis X-X. Particularly as the swivelling or pivoting can be relatively free, and as the weight of the component 12 can be substantial, movement of the component 12 preferably is controlled manually by an operator, as shown in Figure 9. However, as detailed earlier herein, the movement may be controlled by the swivelling of engagement member 20 relative to securement member 16 being retarded, or able to limit the extent to which component 12 can move under apparatus 10.

Claims (17)

1. Apparatus by which an elongate building component is mountable on a lifting device for raising the elongate component to an installation position, wherein the apparatus is adapted for engaging and holding the elongate component in relation to the lifting device and is operable to enable the elongate component, while being raised, to adjust from an orientation in which the longitudinal extent of the component is predominantly horizontally extending to an orientation in which the longitudinal extent is predominantly upwardly extending.

2. The apparatus of claim 1, including a securement member adapted to be secured to the lifting device, such on the platform or similar structure of the device, by bolts or other fastening members able to be engaged with the lifting device.

3. The apparatus of claim 2, wherein the securement member comprises a body portion engageable with the platform, or another appropriate part of the lifting device, with the apparatus further including an engagement member by which the device is adapted for engaging and holding the elongate component, with the securement member and the engagement member being rotatable relative to each other about a swivel or pivot axis.

4. The apparatus of claim 3, wherein the engagement member is adapted to encircle and grip the elongate component, such adjacent to, or towards, one end of the component.

5. The apparatus of claim 3 or claim 4, wherein the engagement member includes a backing part able to bear against the elongate component and a holding part for holding the component securely against the backing part.

6. The apparatus of claim 5, wherein the engagement member is in the nature of a beam, post or column, with the backing part may comprising a plate, and the holding part comprising a chain or strap fixed at one end at or adjacent to a side of the plate and able to be secured at or adjacent to an opposite side of the plate after being drawn around the component.

7. The apparatus of any one of claims 3 to 6, suitable for use with an elongate component in the form of a panel or sheeting, wherein the engagement member comprises a plate to which a stiff or rigid cover is clamped for firmly gripping the component, with the plate and cover able to span the major dimension or width of the component perpendicular to the longitudinal extent.

8. The apparatus of claim 7, suitable for use with profiled sheeting having a depth that is minor relative to the width, wherein with the plate of the engagement member positioned against one of oppositely facing surfaces of the component, from one to the other of opposite sides of the component, the cover of the engagement member is able to be moved so as to extend from the one side to be positioned similarly against and across the other of those surfaces, and then clamped to the plate adjacent to the other side of the component.

9. The apparatus of any one of claims 3 to 8, wherein the engagement member is provided with a facing of a material having a high coefficient of friction over surfaces of the engagement member that are to bear against the component.

10. The apparatus of any one of claims 3 to 9, wherein the engagement member is of a form able to engage an elongate component by contacting, such as to grip, oppositely facing surfaces of the component.

11. The apparatus of claim 3, suitable for use with an elongate component in the form of panels or sheeting, wherein the engagement member comprises a vacuum lifter of a type suitable for carrying sheets of glazing, having at least one suction cup mounted on a backing plate, or a common or respective backing plate where the engagement member has at least two suction cups, whereby with the at least one suction cup held firmly against one of oppositely facing surfaces of the elongate component, the engagement member is operable to firmly engage, or adhere to, the one surface by generation of a substantial vacuum or reduction in pressure between the interior of the or each cup and the one surface.

12. The apparatus of claim 11, wherein the vacuum lifter is operable for generating the vacuum by the action of a hand pump operable to generate pressure between the exterior of the cup and the backing plate and thereby force the cup towards the one surface to displace air from the interior of the cup; or by actuation of a mechanical lever mechanism operable to force the cup against the surface of the component to displace air from within the cup; or by connecting the interior of the cup to a vacuum source by which air can be drawn from within the cup; in each case to attain the required substantial vacuum.

13. The apparatus of claim 3, suitable for use with an elongate component in the form of ferromagnetic panels or sheeting, wherein the engagement member comprises a backing plate on which is mounted a coil of insulated wire formed around an iron core, with the ends of the wire connectable to a direct current power source via a current controller, enabling the engagement member to operate as an electromagnet operable to grip and hold the component.

14. The apparatus of any one of claims 3 to 13, wherein the securement member and the engagement member are inter-connected in a manner enabling the relative swivelling or pivoting. In one arrangement the securement and engagement members are inter-connected by an axle having an axis coincident with the swivel or pivot axis whereby, with the securement member mounted on and fixed relative to the lifting device, the engagement member is able to swivel or pivot on the swivel or pivot axis through a required angle relative to the securement member.

15. The apparatus of claim 14, wherein the swivelling or pivoting is reversible, with angle such as from about 85° to 95°, preferably substantially about 90°, whereby the component is able to swing, or be swung, substantially parallel to an upwardly extending plane, such as a substantially vertical plane, that is substantially perpendicular to the swivel or pivot axis and the axle, such as with the axis and axle predominantly extending horizontally, or substantially horizontal.

16. The apparatus of any one of claims 3 to 15, wherein in use of the apparatus, the engagement member is able to swivel or pivot relative to the securement member as a consequence of the effect of gravity acting against the elongate component being raised.

17. The apparatus of claim 16, wherein the engagement member free to swivel or pivot on the swivel axis and, hence, free to respond to the weight of the elongate component, with an end of the component remote from the apparatus at least initially being drawn across the support surface at the supply level. The apparatus of claim 16, including means by which the engagement member is retarded in its swivelling or pivoting, rather than free to swivel or pivot, so that swivelling or pivoting occurs only through a required angle, such as about 90°, such as by swivelling or pivoting being controlled by the retarding means comprising a ratchet device or a stop acting to limit the extent of swivelling or pivoting to a predetermined limit.