P/00/01 I Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Lifting apparatus for a building under construction The following statement is a full description of this invention, including the best method of performing it known to us: 2 Lifting apparatus for a building under construction Field of the invention This invention relates generally to lifting apparatus for a building under construction, and has particular application to the lifting of loads such as table forms and other formwork 5 components from a lower level where construction is more advanced to a higher level where the formwork is required. Background of the invention A common mode of erecting a multistorey building is to successively pour reinforced concrete slab floors on temporary formwork supported by floors below. Materials and 0 equipment are delivered by crane to loading bays that project cantilever fashion from outer edges of completed floors. Typically, the loading bay has projecting beams that are temporarily bolted to a completed floor. These arms are braced to the next floor above by suitable props: the bolts and props together support the cantilever. Items are craned onto the loading bay and then pushed to the worksite on the floor on trolleys or 5 by other suitable means. When it is desired to move the loading bay to a higher floor, the props are removed and placed on the loading bay, the bolts are removed and a crane lifts the whole unit outwardly and raises it for reinstallation at the higher floor. Transportation of materials between levels during construction is by means of relocatable cages extending vertically over several levels within a series of aligned 20 cavities left, usually temporarily, in the slab floors. The cage is bolted down at its lower edges about the cavity on the lowermost supporting floor. At the top of the cage a motorised hoist is mounted: this is drawn laterally along a projecting rail at the top to bring the hoist over a higher floor position. When desired to move the cage, the lower bolts are removed and a crane raises the cage upwardly through the cavities for 25 remounting at a higher floor. This arrangement is used in particular for moving table forms and other formwork components from under a lower floor into position on the uppermost poured floor ready to support the next pour; for this reason, these cages are often known as table hoists.
3 Cost management is always a key issue for ensuring profitability in the construction industry, and construction companies are continuously seeking improved and more efficient techniques, while being always conscious of the need for no compromises with respect to worker safety. It is to this general objective that the present invention is 5 directed. Reference to any prior art in the specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in Australia or any other jurisdiction or that this prior art could reasonably be expected to be ascertained, understood and regarded as relevant by a o person skilled in the art. Summary of the invention The present invention stems from a realisation on the part of the inventor that it is feasible and advantageous to adapt a loading bay installation to serve the operational role of the conventional table hoist. 5 The invention accordingly provides, in a first aspect, lifting apparatus for a building under construction, including: a frame defining a cage about a vertically extending transfer space; a support frame including means to mount said cage thereto and further including two or more beams for fixing the support frame to a floor of a partly constructed building 20 so that the support frame projects cantilever fashion from an outer edge of the floor; means in an upper part of the cage for supporting a hoist for travel between a first position in which the hoist is operable to lift a load within the cage from a lower part thereof, and a second position laterally of and outside the cage; and means to secure crane equipment to the cage to facilitate vertical repositioning of 25 the apparatus with respect to a building.
4 The frame defining the cage may comprise a network of steel beams and would typically extend vertically for a distance equal to or greater than a plurality of floors of a building, e.g. at least 3 or 4 floors of a building. Preferably, the cage is closed against human ingress or egress on all sides other than that facing the building in use. This may 5 be effected, for example, by metal mesh applied to the frame. In one arrangement, the frame defining the cage includes four or more depending feet, and the support frame includes respective means to receive and seat these feet, preferably with means to detachably fasten the feet in position. The means in an upper part of the cage for supporting a hoist is preferably a rail 0 defining a wheel or pulley track or tracks along which the hoist may travel. Preferably, the apparatus includes a hoist movably mounted on this rail. In a preferred arrangement, the hoist supporting means is disposed somewhat more than two floors above the base of the cage whereby table forms and other formwork may be lifted from the bottom of the cage when level with a first floor to a floor two levels above that first 5 floor. The means to secure crane equipment to the cage will typically include multiple lifting eyes fixed at selected locations on the frame defining the cage, and multiple chains for attachment to these lifting eyes. Preferably, the lifting eyes are in the lower half of the cage, and the cage further includes guides for the chains at upper locations of the cage. O0 Brief description of the drawings The invention will now be further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of lifting apparatus according to an embodiment of the invention shown in position on a partially constructed building; 25 Figures 2 and 3 are respective outer and inner end elevations of the cage frame forming part of the lifting apparatus; 5 Figure 4 is a plan view of the loading bay on which the cage frame is supported. Figures 5A and 5B are respective elevational details of a representative leg support spigot on the loading bay; Figure 6 and 7 are fragmentary detailed elevations showing the mounting of the 5 hoist monorail to the cage frame; Figure 8 is a somewhat diagrammatic fragmentary view of the mounting of one of the crane lifting chains; Figure 9 is a plan view of one of the top corner gussets; and Figure 10 is a cross section on the line 10-10 in Figure 8. 0 Detailed description of embodiments of the invention The lifting apparatus 10 depicted in the drawings includes a frame 20 defining a cage, hereinafter referred to as cage frame 20, a loading bay 50 on which the cage frame is detachably supported when in operational use, a monorail travelling hoist arrangement 70 mounted at the top of cage frame 20, and a built-in chain configuration (to be 15 described) by which the cage frame may be secured to crane equipment to facilitate vertical repositioning of the lifting apparatus. The lifting apparatus 10 is depicted in Figure 1 in operational position on a partially constructed building 100 that presently consists of multiple pillars 105 spaced about a core (not visible), and a number of already poured reinforced concrete slab floors, 20 including floors 101, 102, 103. Slab floors 102, 103 have been constructed on formwork including table forms, one of which is illustrated at 110 between floors 101 and 102. One of the purposes of apparatus 10 is to allow transport of the formwork from between floors 101 and 102 up to floor 103 to be put in position to support the pour of the next slab floor 104 (shown in broken lines).
6 Cage frame 20 is a generally rectangular frame that is wider in the direction outwardly from the building than in the direction facing the building. The main components of the frame are tubular steel beams of square cross-section, including four upright corner posts 22, vertically spaced horizontally extending connector beams 24, of tubular form, 5 and beams 26, 27 arranged as diagonal braces in zigzag fashion at each side of the frame and at the outer end face (Figure 2). These three walls of the frame are internally faced with 25 x 25mm steel mesh 30 fixed to the frame (this mesh is represented diagrammatically by the linked array of black spots 31). At the front or inner face of the frame (Figure 3), there is only a diagonal 27 in an intermediate position and two upper 0 corner diagonal struts 32. As a result, this side of the frame is freely open to insert and retrieve objects in a lower region which in situ would match a habitable space on a lowermost slab floor and in an upper region which would extend in situ from about level with the third slab floor up. The top ends of posts 22 are linked at both sides of the cage frame by tubular connector 5 beams 24 and at the inner and outer ends by channel-section beams 35. The inside corners between these beams are braced by welded-in gusset plates 36 having central holes 37 fitted symmetrically with a respective open-ended length of round tube 38 (better seen in Figures 8 and 9). Top channel section beams 35 jointly suspend an I-section monorail 72 of hoist 20 assembly 70. As best seen in Figures 6 and 7, the top flange 73 of monorail 72 abuts the bottom flange 35a of beam 35 and is bolted thereto by a cradle formed from four vertically aligned bolts 74 and top plate 75. At both suspension mountings, the top flange 73 of the monorail is braced at each side of the centre web by a respective cleat 76. 25 Monorail 72 mounts a trolley 80 with wheels by which the trolley can be drawn back and forth on the lower flange 75 of the monorail. Trolley 80 is motorised and operable via a control cable 86 (Figure 1) by operator 87 standing on an adjacent floor. Trolley 80 carries a winch 82 and a sufficient length of wind-up chain 84 for being hooked to and raising a load from the lower-most region of cage 20.
7 Loading bay 50 is of essentially conventional construction (Figure 4) and comprises a floor 52 with a safety barricade 54 on three sides and a trio of beams 56 that in situ rest on a floor 101 of the partially completed building so that the loading bay floor 52 projects cantilever fashion from the outer edge 101a of the building floor 101. Beams 56 are 5 fixed down by bolts 58 and the cantilever is further typically stabilised by props (not shown) placed between beams 56 and the overlying slab floor 102. The loading bay 50 differs from a conventional loading bay by having cross beams 59 having adjacent each end respective upwardly projecting spigots 60 of square tubular form, with trumpet mouths 62 at their open upper ends. Spigots 60 are mutually spaced 0 and dimensioned to snugly receive the lower ends of posts 22 of cage frame 20. The lowermost connector beams 24, 25 are displaced upwardly from the actual ends of posts 22 to form feet 22a for accommodating this arrangement. In this way, the cage frame 20 is supported by and seats in spigots 60. An appropriate positive connection is provided by transverse bolts in either or both directions through holes 61 in the spigots, 5 and complementary holes in the posts. The cage frame is further stabilised in situ by tie-back stays 64 linking the inner posts 22 to releasable fastenings 69 on the slab floor that is above the current level of loading bay floor 52, and a pair of heavy duty diagonal braces 65 fastened further back on the next slab floor up. 20 For supporting the cage frame 20 from a site crane, each post 22 has a lifting eye 90 bolted onto an inner face so that the lifting eye projects obliquely interiorly within the cage (Figures 8 and 10). Each lifting eye 90 is the lower mounting point for a respective chain sling 92 which is secured to the lifting eye by a suitable bow shackle and hammer lock 93. Each chain sling 92 is fed up through the earlier mentioned tube 38 in gusset 25 36 at the top of the frame and draped from this point as illustrated in Figure 8. The free end of each chain sling 92 carries a link 94: links 94 are the means by which the four chains may be suspended from the jib hook or other tackle of a site crane for manipulating the lifting apparatus between operational positions on the building.
8 With the whole lifting apparatus in situ as illustrated, it can be employed for hoisting equipment, most particularly table forms and other formwork, from slab floor 101 up to slab floor 103. Trolleys are employed to roll the equipment onto the floor 52 of loading bay 50, the winch chain 84 is then lowered and hooked up to the current item to be 5 raised, and the winch operated to elevate the item, after which the hoist trolley is drawn along monorail 72 to bring the equipment onto slab floor 103. This process can be used to bring equipment in due course from slab floor 102 to the newly poured slab floor 104, after which it is necessary to reposition apparatus 10 vertically. One approach is to hook cage frame 20 to the jib of a site crane by means of 0 chain slings 92, disconnect the frame 20 from loading bay 50, either by decoupling spigots 60 from posts 20 or decoupling spigot support beams 59 from the loading bay, and to then unfasten stays 64,65 and drop them against the frame posts 22. The cage frame 20 can then be craned away and loading bay 50 is available for other uses. In due course the loading bay 50 can be detached from its current slab floor in the usual 5 manner and craned upwardly for reconnection to slab floor 103. Cage frame 20 can now be returned into position on the higher loading bay and mounted again into position to perform its role. In an alternative approach, the cage frame 20 can remain mounted to loading bay 50, and the loading bay dismounted from slab floor 101 and the apparatus craned as an 20 assembly. It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.