GB2060559A - Movable hoist - Google Patents

Abstract

This invention concerns hoists suitable for use with apparatus for refurbishing overhead structures and provides a hoist 40 comprised of a movable base structure 48 which normally rests upon the ground and carries parallel tracks 47, a hoist base unit 45 for rolling-contact movement along said tracks by wheels 46, a hoist tower 41 extending upwards from securements to said base unit, and a hoist to be raised and lowered on said tower, the tower being adapted to be stayed or braced from an intermediate height position 42 outwards and upwards to a movable overhead working platform 13D at least during erection, and the hoist base unit and its tower subsequently being movable together with said working platform, especially where the base unit is relatively massive and heavy and the tower is lightweight say of aluminium alloy tube frame construction. <IMAGE>

Description

SPECIFICATION Hoist apparatus This invention relates to hoists suitable for use with apparatus for refurbishing overhead structures.

We have successfully developed and are continuing to develop apparatus and systems for refurbishing as aforesaid and utilising a working platform suspended from rails and movable therealong. A principal operating advantage is the possibility of refurbishing roofs, bridges, etc.

without interfering with activities normally taking place below.

Often, the structures to be refurbished are very high, for example railway station roofs, and it is impractical, dangerous or unsatifactory to rely upon ladders or flexibly suspended hoists for taking up materials and personnel, especially for heavy or unwieldly loads. Also, of course, the alternative of fixed columnarscaffolded hoists is somewhat self-defeating as it has to be dismantled and reassembled at each substantial move of the overhead working platform.

It is an object of this invention to provide a more satisfactory solution to these problems concerning raising of loads to a movable overhead working platform.

To this end one aspect of this invention concerns a hoist comprised of a movable base structure that normally rests upon the ground and carries parallel tracks, a hoist base unit for rollingcontact movement along said tracks, a hoist tower extending upwards from securements to said base unit, and a hoist to be raised and lowered on said tower, the tower being adapted to be stayed or braced from an intermediate height position outwards and upwards to a movable overhead working platform at least during erection, and the hoist base unit and its tower subsequently being movable together with said working platform, especially where the base unit is relatively massive and heavy and the tower is lightweight say of aluminium alloy tube frame construction.

Conventional flanged wheels and rails as said tracks are satisfactory for said base unit, but other arrangements could be used, for example tyred wheels in a bounded trackway or trackways, contoured rollers engaging a rail, or plain rollers in conforming channels as said tracks, and so on.

The base unit is preferably sized in excess of the cross-section of the hoist tower comfortabiy to accommodate a hoist load platform and assist in stably seating the hoist tower with the or a hoist load platform following or leading the tower in the direction of movement of the base unit. In elevation along that direction the tower and base unit may advantageously have an inverted T-configuration.

Obviously, the movable base structure could have an extent in that said direction substantially in excess of the hoist base unit. However, we particularly prefer, herein, for that not to be the case so as to avoid cluttering normal working space and floor area. Thus, we propose herein that movement of the hoist base unit be preceded by emplacement, with registration of tracks, of a further base structure end-to-end with that then carrying the hoist base unit, for movement of the latter onto the newly emplaced base structure and thereby allow the other base structure then to be moved away.

The movability of the base structure is thus desirably easy to achieve and, to that end, we propose the use of raisable and lowerable wheels or rollers, say as screw-jack mounted castors or wedge-operated, end-pivotted, wheel-carrying arms. Such means readily permit the base structure to be in overall floor engagement when carrying, or about to receive, the hoist base unit.

Suitable base structures comprise lengths of rail on cross-sleepers and equipped with retractable wheel or roller units at or near each corner.

In view of the inevitable height of the base structure and the hoist base unit, it is preferred for the latter to have a ramp pivotted thereto, also for raising onto a jockey wheel or wheels or the like during movement. Such a ramp is advantageously positioned to lead in the direction of movement of the hoist base unit.

The hoist base unit stability may also be increased in an advantageous manner, whilst retaining minimum weight of its extensions beyond the mount position for the scaffold, by ballasting at and adjacent that position, say by concrete infilling of a cavity. Such provision is also of assistance in relation to the preferred mode of erection of the hoist tower by erecting a first section thereof, loading the hoist platform with other sections sufficient for other stages to reach the bracing or staying position, raising the hoist platform successively up the partially built tower in continued building thereof from that hoist platform, bracing or staying to the overhead platform, then lowering and reloading the hoist platform with further tower sections, raising same and repeating the least two operations as and if necessary to bring the tower to the height of the working platform.

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows part of one particular overhead refurbishing system complete with hoist; Figure 2 is a side elevation of the lower part of the hoist of Figure 1; Figure 3 is an end elevation of what is shown in Figure 2; Figures 4 and 5 are plan and sectional view of a hoist base unit bogie; Figure 6 is a plan view of tower support framing of a hoist unit bogie; and Figures 7 and 8 show details for preferred base structure and hoist base unit movement.

The installation of Figure 1 is actually made relative to an arched railway station roof 10, see also platform areas 11 and train wells 12. A composite overhead working platform is shown with platforms 1 3A and 1 3D at different heights, platform 1 3D being assumed to be topmost and spanning the crown of the roof 10 with other platforms similar to 13A, B and C on the other side of the arch.

After the general manner of our application no. 43429/76, the platform 13, though composite, is suspended at 1 4A to 1 4E from rails 1 5A to 1 5E themselves suspended at 1 6A to 1 6E from couplings 1 7A to 1 7E to span a plurality of successive roof arches, such as 18. There will be provision for rolling-contact trolley type couplings between the rails 1 5 and the suspensions 14 and 1 6 so that the rails 1 5 can themselves be advanced alone, and the platform 13 itself moved along the rails 1 5, in succeeding phases of use of the installation in progressing along the roof 10 normal to the plane of Figure 1.The individual platforms 1 3A to 1 3C are also shown suspended successively one from the other at 1 9A to 19C.

This particular adaptation, modification or improvement of the system actually described in our patent application no. 43429/76 has significant advantages in minimising space obstruction below an arched overhead structure.

Furthermore, to avoid having to move the entire composite platform 13 together, and to make optimum use of a relatively large and long main central platform component 13D, we actually prefer that suspension 1 9C be as shown at detail 20 using a rail 21 fixed at 22 to the platform 1 3D and a roller-trolley coupler 23 to suspension 1 9C which, rather than being a length-adjustable flexible wire or cable is actually shown as two links 24 and 25 pivotted together at right angles and to end pivots using D-shackles 26, 27 and 28, as shown, to give universal freedom of flexing.If platforms 1 3A to 1 3C are to move together, the suspensions 1 9A and 1 9B need have only components equivalent to those referenced 24 to 28 with D-shackles 27 secured to brackets of the higher platform. It is preferred that main platform 1 3D be about twice as long as platforms 1 3A to 13C, which may be of equal lengths. It will be appreciated that there may be more or less than the three subsidiary platforms 1 3A to 13C at different heights, if desired, and further analogous provision might be made for separate movement thereof if of unequal length.

The flexibility of the suspension shown at 20 will normally be matched, at least by suspensions such as 14E, for the main platform 1 3D to rails 14E. Whilst similar flexibility may, on occasion, be desirable at suspensions 1 4A to 1 4D that are much closer to the roof arches such as 18, we have found it preferable to provide a coupling as shown at detail 30, where brackets 31 correspond to suspensions and couplers 16/17, double-bolted plate-coupler 32 corresponds to suspensions 1 4A to D, and roller trolleys 33 and 34 provide for translation of both of the rails 1 5 and the platforms 13.Such an arrangement is still tolerant of at least gentle curves in plan, but does give a good synchronism of movement of the platforms 1 3A to 13C, usually by winching from the main platform 13D. It also means that just one rail needs to be advanced from each of the platforms 1 3A to 13C, though such is in no way a limiting feature if circumstances, such as a hipped roof, require more than one rail suspension of one of the platforms 1 3A to 13C.

We now turn to the hoist, shown at 40 as comprising a light-weight frame tower 41, preferably of aluminium alloy, square-section tubing, braced from an intermediate height 42 to the main platform 1 3D at 43, 44. Preferably such bracing 44 is in at least two directions, shown at a preferred right angle in detail 38 with further brace 39 between them. Bracing to the platform 13C would only be practical if that platform was not to be movable relative to platform 1 3D as envisgaged above. The hoist tower 41 could be made up from scaffolding components, it is actually built up in sections, see darker horizontal lines, from a heavy hoist base unit 45 that can travel by wheels 46 on rails 47 of a base structure 48.We shall return to Figure 1 in order to describe assembly of the hoist 40, but will first refer to the remaining Figures for details and other advantages.

The base structure 41 is shown to comprise a set of sleepers 51 carrying the rails 47 bolted or otherwise affixed thereto. Steel channel members 52 and 53 are shown extending transversely of the rails 47 near each end of the base structure and serve to carry brackets 55 for bodies of raisable and lowerable castor wheels 56 indicated as being of the screw-jack type. The base structure 41 is thus selectively readily movable or not according to the positions of the castor wheels 56.

The hoist base unit 45 comprises a steel frame 60 carried by a bogie 61 having bearing holders 62, 63 for wheel axles 64, 65 of the wheels 46, which are flanged to run on the rails 47. The bogie 61 is also shown as having a rail brake device 66, and there may well be one of these on each side, i.e. one for each rail. On the frame 60 is shown a hoist-seating unit 67 as required by a hoist platform 68, which will normally carry a cage and be a bought-in unit with such modifications as may be necessary to its seating unit 67.

The frame 60 carries a securement base 70 for the hoist tower 41, say at leg mounting positions 71. It will be noted that the tower 41 is actually shown to one side of the bogie but centrally of the length thereof. The latter is important for stability of the hoist as a whole and it may well be that the tower 41 will, wherever possible, be central of the width of the bogie also.

To provide increased working space and accommodate the hoist seating unit 67 on the hoist base unit the frame 60 extends sideways beyond the bogie at 91 but its frame girder structure has an inner longitudinai beam 92 over the bogie edge and supporting transverse beams 93 between its side beams 94,95. Two of the transverse beams are spaced to correspond to the desired scaffold base and further strengthened by braces 96 that could accommodate hoist buffer springs.

Lengthwise of the rails 47, the hoist base unit frame is shown with an overhang 72 beyond the hoist platform position. That overhang 72 carries a load support platform 73, shown covered by a pallet or the like 74, for parking loads prior to hoisting them. It will be noted that the pallet top is level with the hoist platform top to aid loading.

The platform 73 may, if desired, be of adjustable height to facilitate this matching of levels regardless of whether pallets are used or the height of such pallets.

At the free end of the overhang 72 we also show a ramp unit 76 for loading and unloading, say when fork lift trucks are not available or not required. The ramp unit 76 has cross-members 77 between side beams 78 and may simply be covered with heavy-duty plywood or planking as desired. The side beams 78 are chamfered 79 at their ground-engaging ends to further facilitate loading and unloading. The other ends of the side beams 78 are shown carrying depending ears 80 which are pivotted 81 to end-parts of the overhang 72 of the base unit frame 60. This enables the ramp unit to be raised and lowered.

This is required for movement of the hoist base unit 45 along the rails 47 from one base-structure 41 to another as will be described. A transverse channel member 82 is thus shown secured under the ramp unit 76 and extending beyond the width of the base structure 48 whareat the channel member 82 also carries screw-jack type castors 83, 84.

Whilst normal towing of the hoist base unit 45 along the rails 47 can be, and perhaps normally would be, with the ramp unit trailing, the particular arrangement shown can, in fact, be towed from 85 in the opposite direction. That is, in fact, preferred herein as activities may well start at one end of a structure carrying that to be ;efurbished, and so will allow ramp loading of the hoist only from its front relative to the direction of future movement.

Then, the ramp unit 76 will first be raised on its castors 83, 84 sufficiently for a further base structure, such as 48, is rolled into place below the ramp unit and end-to-end with the base structure then carrying the hoist base unit, and with rails in registration. That further base structure will then be dropped onto the floor by raising its castors, any sleeper packing necessary to match levels made, the rail brake devices released and the hoist base unit towed onto the further base structure. That will be done simuitaneously and in synchronism with movement of at least the main overhead platform 1 3D, to which the head of the hoist tower may be secured directly after it is built, rather than relying on the bracing 43.

However, the bracing 43 is of particular value in building the hoist tower 41 by our preferred method. That is to build the first stage of the tower from the hoist base unit, load the hoist platform with enough tower stages to reach the position 42, which obviously should be below a level at which the hoist platform can tip the whole apparatus by its weight. The part of the tower up to position 42 is then built from the hoist platform.

The stays or braces 42, and 44 if used, will be secured, whereupon the remaining required height of the tower 41 is completed using the hoist platform.

The resistance of the hoist to tipping during initial tower erection, and stability generally, is increased usefully by ballasting a central portion 85 of the bogie as shown in Figures 4 and 5, where shuttering 86 and reinforcing rods 87 and mesh 88 are shown between cross-beams for infilling with concrete.

Advantageous variations for the ramp 76 include the provision of a winch-and-pulley operated cable system for raising the ramp on movement of the hoist. A winch on the hoist base unit and a pulley or pulleys on the tower is preferred. Also, they can be made as two portions hinged together at a position beyond that of jockey wheels such as 83, 84 so that the lower, ground-engaging portion can be swung up and over onto the upper portion during such winching, thereby reducing the power required and stress on the overall hoist structure. Such an arrangement also, of course, allows for the slope of the ramp to be shaliower for the same lifted ramp length (when folded) shown in Figure 2.The upper portion will need support strutting to the ground at or beyond the position of jockey wheels 83, 84 and the lower portion will have a top hinge thereto and either can have a bottom plate that can be bolted through to the other. It may well be further advantageous to include the jockey wheels 83, 84 together with a further pair flanking a higher position of the upper portion so that the entire ramp assembly, at least when folded, can be wheeled about as a unit.

We have also found it advantageous for the hoist base unit to be fitted with rail clamps at each of its corners, say on brackets extending therefrom, so as to give improved stability in use.

We have also developed a working platform construction system that utilises light-weight aluminium alloy and timber parts so as to give a highly advantageous structure that is both flexible in its capacility to cope with different sizes of platform and of low overall weight for its required strength.

To this end, see Figures 9 to 15, square-section aluminium alloy tube is used in the construction of beams 100 comprised of upper and lower rails 102, 103 secured together by spacers 104 and diagonal braces 105. Such beams 100 are made in lengths to suit each of a variety of panel sizes, or combinations thereof as indicated in Figure 11.

These beams 100 serve to support floor bearers 110 also of square-section aluminium alloy tube to extend transversely of the beams 100 on assembly thereto. Floor bearers 11 OA and 11 OB extend between beams 100 at their ends, whilst floor bearers 11 OC and 11 OD cantilever over a beam 100 at one end 112 as is often desirable at edges of a working platform. Floor bearers 11 OA and 11 OC are for securement by coupling brackets 113 and clips 114 at their ends to the beams 100 simply by pins 11 5 through holes 116. Floor beams 11 OB and 11 OD are to extend intermediate those 11 OA and 11 OC and have simple angle brackets 11 8 secured thereto to butt onto top rails 102 of the beams.Timber flooring 119, e.g. plywood sheeting, is secured to the floor bearers 110 by way of self tapping screws 120.

The brackets 113 are shown in detail 121 in Figure 10 as saddle pieces with an upper full length channel 123 and aligned therewith, lower end channels 124, 125 one to each side of a bridge formation 126 fitting over top rails 102.

The upper channel 123 will receive opposed ends of floor bearers 110 of adjacent panels and has holes 127 to register with floor bearer holes 116 and allow interfixing by the pins 115. The brackets 113 are located on the top beams 102, at angles between spacers 104 and braces 105, by retaining clips 114 of generally U-shape with cranked ends 131 to be secured through holes 132 in inner walls 133 of end channels 124, 125.

Similar holes in outer walls 135 of end channels 124, 125 can serve in the same manner, with location of diagonal bracing tubes 139 by pins 115 in holes 133 as shown at the left hand side of Figures 9 and 10.

Another saddle bracket 140 is shown (Figure 10 only) and resembles that 113 save for omission of its upper channel. The brackets 140 are used on bottom rails 103 of the beams 100 for pin location of horizontal ties 141 and the other ends of braces 139.

It will be appreciated that, except for free ends of preferably cantilevered edge panels, the floor bearers 11 OA, B of adjacent panels effectively share a common beam 100 due to angle brackets 118 and coupling brackets 113.

The timber flooring 119 will normally be coextensive with the associated floor bearers 110 but need not be coextensive with the beams 100, see coupling bracket 113' at a cantilever position of the top beam 102 for braces 139 and ties 141.

The beams 100 themselves are coupled together where they abut, as shown at adjacent panels, also by means of pins 11 5 through holes 1 51 1 52 therein using close fitting inner coupling tubes 153.

Using the parts thus for described, it will be evident that beams 100 may be assembled together using coupling tubes 1 53 in any permitted length, and be cross-tied and braced (139, 141) as desired following location thereon of coupling brackets 113, 140, all by a simple knock-up procedure using pins and clips secured in place by split or spring pins such as 1 54 through holes shown in their ends. The location of the coupling brackets 113 will allow pinning in of floor bearers 11 OA and 11 OC with floor bearers 11 OB and 11 OD located as required by the timber flooring then readily applied by self-tapping screws 120 as aforesaid.

However, the overall platform structure may further require bracing diagonally and horizontally of its overall structure. That is readily achieved, prior to fitting the floor bearers, using brackets 160 of a type having a channel 161 extending Tfashion from a right triangular recess 1 62 centrally of lugs 163 and 1 64. Two such brackets clamped with their lugs back-to-back on a vertical beam spacer 104 by bolting 1 65 afford pin location of square-tube bracing 1 66.

One particular platform configuration is shown in Figures 11 and 14 using the various sizes of panel numbered 1 to 6, complete with diagonal horizontal bracing 166, which will clearly be at different heights where crossings are required as shown in Figure 14.

For safety reasons we prefer that our platform is fenced at least at edges transverse of the beam top rails 102. To this, end posts 170 have extension tubes 1 72 to fit into the top rails 102 and be pinned therein at 173, and brackets 174 are provided to be pinned at 175 onto the posts 170 and enable pinning therein at 1 76 of hand rail sections 1 71 at least at their end abutments or joints.

Finally, beams 1 80, 1 82 are shown extending into and across the platform at right angles away from the position of hoist tower 41for hoist 68 to serve in located the top of the same, and access to couplings, etc. may be by way of shortened flooring 1 90 of panels covered by a trap 1 92 with location fillets 193 and slotted at 191 for removal of a key 194.

Reverting to the hoist bracing vertical bracing 37 will be noted and serves to ensure that the bracing as a whole is self supporting. That allows position 42 to have provision for selectively permitting relative vertical movement of the tower 41 and the bracing so as to accommodate to variations of height between the floor 11 and overhead structure 10 encountered as the hoist 40 and platform 1 3D are moved together. The bracing at position 42 may thus have a roller device that is lockable relative to the hoist tower and normally captive thereto.

It will be appreciated, of course, that details of hoist tower sections and their bracing are omitted from Figure 1 above the position 42 only to avoid cluttering the drawing.

As an alternative to the saddle brackets 11 3 and clips 114, holes may be formed in the beam rails and in the bracket cheek portions straddling them to enable pinning (e.g. 11 5, 1 54), directly through brackets and rails. Such an alternative can be used in place of bracket 140. Also, the bracket parts 1 60 need not be of a clamp type, but rather be interfitting male and female parts having registering holes by which they are secured together through holes in the bracing 1 66, and other holes by which they are located on the bracing 1 66 to straddle a junction therebetween.

Claims (14)

1. A hoist comprising a movable base structure which normally rests upon the ground and carries parallel tracks, a hoist base unit for rolling-contact movement along said tracks, a hoist tower extending upwards from securements to said base unit, and a hoist to be raised and lowered on said tower, the tower being adapted to be stayed or braced from an intermediate height position outwards and upwards to a movable overhead working platform at least during erection, and the hoist base unit and its tower subsequently being movable together with said working platform.

2. A hoist according to claim 1, wherein the base unit is relatively massive and heavy and the tower is lightweight.

3. A hoist as claimed in claim 2, wherein the tracks are conventional rails, and the base unit has flanged wheels.

4. A hoist as claimed in claim 2, wherein the tracks are bounded trackways and the base unit has tyred wheels.

5. A hoist as claimed in claim 2, wherein the tracks are rails and the base unit has contoured rollers.

6. A hoist as claimed in claim 2, wherein the tracks are channels and the base unit has plain rollers for movement in said channels.

7. A hoist as claimed in any one of claims 1 to 6, wherein the base unit is sized in excess of the crciss-secticn of the tower.

8. A hoist as claimed in claim 7, wherein in elevation along the direction of movement of the base unit the tower and base unit have an inverted T-configuration.

9. A hoist as claimed in any one of claims 1 to 8, wherein the base structure is movable on - raisable and lowerable wheels or rollers.

1 0. A hoist as claimed in claim 9, wherein the base structure is movable on screw-jack mounted castors or wedge-operated, end pivotted, wheelcarrying arms.

11. A hoist as claimed in any preceding claim wherein the base structure comprises lengths of rail on cross-sleepers and is equipped with retractable wheel or roller units at or near each corner.

12. A hoist as claimed in any one of claims 1 to 11, having a ramp pivotted to the base unit.

13. A hoist as claimed in any one of claims 1 to 12, wherein the hoist base unit is ballasted.

14. A hoist as claimed in claim 13, wherein the ballast is concrete filling a cavity.

1 5. A hoist as claimed in any one of claims 1 to 14, wherein the tower is of aluminium alloy tube frame construction.

1 6. A hoist as claimed in any preceding claim, wherein the bracing between the tower and said platform is self-supporting and capable of vertical movement relative to the tower when the hoist and platform are moved together.

1 7. A hoist substantially as hereinbefore described with reference to and illustrated in the accompanying drawings.