TITLE: MULTI-PART BEAM

FIELD OF THE INVENTION

This invention concerns multi-part beams and equipment incorporating such beams.

BACKGROUND OF THE INVENTION

In building and construction it is common to rely on load lifting operations. Indeed many operations are planned around the capacity and availability of cranes. It is customary in

urban and rural areas to have crane hire service where customers can select what type of crane suits their requirements. Such cranes must be mobile or erectable at the site for the period of construction and then removable to a fresh site. It is to this latter type that this invention applies.

It is usual in high rise buildings for the plant for heating/cooling, water supply and emergency power generation to be installed when the building is built using the same cranes which were used for the buildings construction. As such plants eventually require replacement or extensive repair, the maintenance staff find the goods lifts are too small to accommodate the necessary equipment and so the plant continues to deteriorate.

We solve this problem by the introduction of a small derrick crane which is assembled by hand from components, each small enough to be carried to the top of the building in a goods lift. The power units are correspondingly small and can utilise 3 -phase power . available inside the building. The crane has a capacity of 9 tonnes and sufficed to bring up from ground level to the plant floor level, pieces of equipment too large or heavy to reach that level by any other route.

The establishment of a crane, even a small one on a roof of a high rise building presents problems. The roof must make provision for window cleaning gantries which run around the perimeter on rails raised above roof level. The rails impede the peripheral area of the roof, whereas the centre is occupied by cooling structures, aerials, dishes, and tanks. The feet of the crane must be sited directly above columns inside the building and a civil engineer must check that the load transmitted downwards by the crane is taken on, columns and the anchorage of the part of the crane which tends to uplift when the jib lifts a load must also be tied to an interconnected part of the building and not just the floor slab. The best places for uplift resistance are the areas immediately adjacent the columns where the reinforcement is stiffest. This requirement introduces a problem with the crane design in that the disposition and spacing of columns differs appreciably from building to building.

In rural situations the problem is different again in that a crane may be required to be

supported on the ground beside a site where a bridge is to be built. The crane is not mobile and must be supported on reliable, non-sinking pads. Both situations require crane support of adjustable geometry.

US Patent 5,406,767 describes the construction of a crane jib from segments which allow assembly and disassembly in order to make the segments small enough to be transported on a highway. The segments have chords braced by tubular lacing and have dovetail shaped connectors which permit locking and unlocking to make a unitary jib.

US Patent 5,406,767 describes a beam construction built up from modules to reach a desired length. The modules are held together by tensioned stringers and the beam or truss is suitable for light loads such as a roof.

SUMMARY OF THE INVENTION

An apparatus aspect of the invention provides a beam of adjustable length made of parts, each of which is capable of being lifted by two persons and is of a length which will permit carriage in a service or passenger lift of a building.

More particularly the invention provides a sill beam longitudinally divisible into multiple modules which are capable of individual manhandling, at least some of the modules comprising a first and second channel section beams, the beams defining an elongated access space between them, each beam being closed at one end by an end wall and being closed at the opposite end by an enlarged end wall such that the enlarged end wall of the first beam bridges the access space and overlies the end wall of the second beam and when modules are placed end to end the two enlarged walls lie in register and each end wall abuts an enlarged end wall, whereby fasteners connecting the modules join together two enlarged end walls and an end wall.

The endmost module may be modified to adapt it for connection to the turret. The end wall may be of double thickness with a margin surrounding the module, the margin being braced by ribs. This modified module is bolted to the turret.

- A - The opposite endmost module may be modified to include a backstay mount.

While the modular construction is essential if the beam is to reach the roof of a high building via the lift, usually the service lift, the beam provides suitable adjustability if the axial slot only extends along part of it or the slot is intermittent. Clearly it is useful to have the slot availability at the backstay end of the beam rather than the turret end. These variants and a series of downwardly facing apertures, instead of a slot, would be equivalent.

In a variant, the modules each comprise a pair of channel bearers each with an end wall bored to take fasteners, a spacer plate and to take fasteners interposed between pairs of channel bearers when placed end to end in order to connect consecutive bearers and to create an upright axial slot between pairs of bearers for the reception of a bearer holdfast.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention is now described with reference to the accompanying drawings, in which:

Figure 1 is a side view of a derrick crane incorporating sill beams according to the invention.

Figure 2 is a diagram of a fragment of a roof to show placement of the derrick crane.

Figure 3 is an exploded perspective of two modules end to end.

Figure 4 is an exploded plan view of a beam showing how the parts are assembled.

Figure 5 is a plan of the beam of Figure 3.

Figure 6 is a side view of the turret end of a beam showing fish plates between modules and the modification to clamp the beam to the turret.

Figure 7 is a side view of the backstay end of the beam showing the mount for the backstay.

Figure 8 is an end view of the mount shown in Figure 6.

Figure 9 is an exploded perspective view of a variant module.

Figure 10 is a section of the variant module of Figure 9.

This embodiment makes it possible to build the sill beams on the flat roof of the building or onsite whereafter the construction crane lifts them to operating height where the crane crew assemble the derrick crane. Upon completion of the construction the construction crane is dismantled and the crane parts are lowered to site level by the derrick. The derrick crane is finally dismantled and the parts including the sill beams, jib and turret are all carried or wheeled by trolley into the service lift and taken to site level.

In this way the derrick crane moves from moulding to building or site to site.

DETAILED DESCRIPTION WITH RESPECT TO THE DRAWINGS

Referring now to Figures 1 and 2, a derrick crane has a turret 2 supporting a mast 4 (5m) and a jib 6 (26m). A pair of sill beams 8 are bolted to the turret and these extend at 90° where they anchor a pair of backstays 10. The jib slews in an arc in order to use roof space 12. Line 14 controls luffing and line 16 is the hoist line. The winches are not shown but are located to the side of the crane on the roof space. For high rise buildings the hoist line may need a reel 2m in diameter.

In Figure 2 the roof slabs span the array of columns 18 which support the building. This , array may not be regular as shown and these may be more clustered around the core of the building. The column distribution is determined from construction drawings and the site for the derrick crane is selected clear of the window cleaning gantry and marked such that the turret and the anchorage sites for the ends of the sill beams overlie three columns

or similar structure which take the crane load. Screw hold fasts engage the beam and pass through the floor slab adjacent the column in order to clamp the crane to the building.

If the intention is to lower parts of a construction crane to the ground a different position may be selected from that shown but the crane operators always have the responsibility of adjusting the geometry and reach of the derrick sill beams to take loads safely. If the beams must be of unequal length or the angle between them must be adjusted, then this sill beam construction makes it possible.

Referring now to Figures 3 and 4, the sill beam is made from 1300mm lengths of 300 x 90 x 5mm parallel flange channel (grade 300+ steel) 20, 22.

One end of the channel is closed by an end wall 24, 190mm deep and 30mm thick. The opposite end is closed by a steel plate 22, 300 x 300mm of the same thickness. The walls are attached by 10 x 45° bevel welds and central fillet welds. An asymmetric tray structure is created with one enlarged end wall 26. The end walls both have symmetric arrays of four bores 28 at 50mm centres. These components are paired in the manner shown in Figure 4 and 5. The channels are separated by an elongated slot 30, 140mm wide. This slot admits the operators arm and a torque spanner so that bolts can be inserted. A washer is placed on the outside and the nut tightened.

When the modules are placed end to end as shown in Figure 4, each bolt passes through three end walls. The resulting beam is 4-5m long and is of sufficient strength and stiffness to resist bending when loads are suspended.

The strength of the beam is increased by the addition offish plates 32. The connecting bolts pass through bores 34. See Figure 6.

The turret end of the beam is modified as shown in Figure 6.

The channels are still 1300mm long but a square end wall 36, 510 x 510mm of double

thickness is welded to the channels and the margin 38 is braced by welded ribs 40.

Bores 42 at 75mm centres allow bolts to enter the turret wall (not shown but see Figure

1).

The opposite end of the sill beam is modified as shown in Figures 7 and 8. The channels 20, 22 are closed by a single end wall 44 to which an external eye 46 is welded for lifting. The channels are reversed so that the upright walls 48 define the access slot. The flanges 50 are supported by three inserts 52 and the walls 44 are interconnected by overlapping strips 54. A pair of backstay mounts 56, 58 are welded to the top flanges of the module. They carry a shaft 60 which in turn engages the eye of the backstay 10.

A pair of screw clamps 62 are inserted into the access slot and then passes through the roof slab into the column as earlier described in order to resist uplift of the sill beam when loads are carried and the jib slews. Each screw clamp has a bar spanning the beams and a plate under the floor slab which spreads the load. The annular zone surrounding a column is suitable because the steel reinforcement ties the slab to the column.

The heaviest component is the turret. The jib, mast and backstays are made of modules 1300- 1500mm long whiph are assembled and disassembled by hand by the crew at each job.

Referring now to Figures 9 and 10, a pair of steel channel bearers 20, 22 are 1500mm long, 300mm deep with 90mm flanges. The ends of the channel bearers are closed by end walls 24 and each wall has an upper pair of bores 70, 72 and a lower pair of bores 74, 76. During assembly a pair is laid side by side with the backs of the bearers facing each other and separated by the same axial slot width as in Figures 3 and 5. Spacer plate 78, 20mm thick has four pins 80 all with conical ends which project from the obverse and reverse faces of the plate. The pins are an interference fit in bores drilled in the plates. Four extra bores 82 lie beside the pins. When a consecutive pair of bearers is pushed against the plate the pins enter the corresponding bores 70, 74 in the end walls while the unoccupied bores are each available to receive a nut and bolt 84. In this embodiment the

assembly bolts are outside the axial slot and easily accessible to the assembler. During assembly the beams are supported on packing plates 86.

We have found the advantages of the above embodiment to be:

1. The sill beam structure ensures that a slot will overlie two or more column sites beneath a building roof. This facility is combined with strength and mass which can be manhandled.

2. The sill beam end is adaptable for connection to the derrick turret.

3. The slots serve to both provide a choice of holdfast sites and to provide access to the fasteners for assembling and disassembling the assemblies.

It is to be understood that the word "comprising" as used throughout the specification is to be interpreted in its inclusive form, ie. use of the word "comprising" does not exclude the addition of other elements.

It is to be understood that various modifications of and/or additions to the invention can be made without departing from the basic nature of the invention. These modifications and/or additions are therefore considered to fall within the scope of the invention.