Background Art All construction platforms comprise a supporting base adapted to be fixed to a floor of a building under construction and a loading deck mounted on or to that base, which, in use, extends outwardly beyond the edge of the floor.

Conventional construction platforms fall into three categories, namely; 1. Fixed deck platforms wherein the loading deck is fixedly secured to or is integral with the base.

2. Fully retractable platforms wherein the base is inboard of the floor and the loading deck is carried by the base in a manner permitting the deck to be extended as a cantilever beyond the edge of the floor and retracted to a position where it is substantially inboard of the floor.

3. Partly retractable platforms wherein the base projects to some extent beyond the edge of the floor and the loading deck is carried by the base in a manner permitting the deck to be extended as a cantilever beyond the outboard edge of the base and retracted to a position where it is at least substantially in register with the base.

Category 2 platforms are advantageous in that the platforms may be disposed one above the other, since the loading decks of upper platforms may be retracted to provide crane load access to lower platforms. Category 3 platforms are nearly as advantageous as category 2 platforms in that respect and allow a somewhat lighter construction to be used for the loading deck because of the reduction in its cantilever overhang. On the other hand, category 1 platforms are simpler and cheaper than either retractable platform. Platforms of all three categories are found in the market in Australia and overseas.

The minimum base width is dictated by the need for fork lift trucks and like mechanised load transporters to be driven across the base to pick up loads deposited by the crane on a load-receiving portion of the loading deck or to deposit loads on the load-receiving portion of the loading deck to be up-lifted by the crane. This width usually corresponds closely to the maximum width of loads that may be transported through city streets without need for special arrangements applicable to wide loads.

Hitherto, the width of the loading deck has been substantially the same as that of the base. This has limited the volume of loads able to be handled conveniently by prior known construction platforms. It has also meant that it has been inconvenient, indeed often dangerous, for dogmen and others to work on the loading deck during loading and unloading operations.

Summary of the Invention.

The present invention is applicable to construction platforms in all three categories mentioned above.

An objective of the invention is to alleviate the inconvenience and danger indicated above due to constricted space on the loading deck, without incurring the substantial disabilities inherent in the transport of wide loads by road, when transporting construction platforms to and from building sites.

In a first aspect the present invention consists in a construction platform of the kind comprising a base adapted to be secured to a floor of a multi-storey building under construction and a loading deck integral with or carried by the base, which, in use, projects as a cantilever from the base to provide a load-receiving portion that is outboard of the floor, characterised in that the load-receiving portion of the loading deck is flanked on at least one side by a demountable or laterally retractable personnel deck for the support of personnel working on the construction platform.

By"laterally"retractable it is meant that a personnel deck so described is mounted to the loading deck in a manner enabling the personnel deck to be shifted from an in-use

position wherein it extends beyond a side edge of the loading deck to a retracted position wherein it is substantially superimposed on the loading deck.

In preferred embodiments of the invention there are two personnel decks, one on one side of the loading deck and the other on the opposite side of the loading deck.

As the, or each, personnel deck is only required to support the weight of at most three or four people, more usually only one person, it may be much lighter in construction than the loading deck proper. This facilitates the operations of mounting and demounting or extending and retracting the, or each, personnel deck while the construction platform is installed on an above ground storey of a multi-storey building.

Conventionally, safety barriers extend along the side edges of the loading deck of a conventional construction platform, whereas in platforms according to the invention those safety barriers are not present. Instead, similar safety barriers extend along the free edges of the, or each, personnel deck. Thus, even in embodiments of the invention where the, or each, personnel deck is demountable, the construction platform cannot be safely used until the, or each, personnel deck has been put in place as an operative component of the platform.

In a second aspect the present invention consists in a construction platform of the kind comprising a base adapted to be secured to a floor of a multi-storey building under construction and a loading deck carried by the base, which, in use, projects as a cantilever from the base to provide a load-receiving portion that is outboard of the floor, characterised in that the loading deck is a single wing unit that in an in-use configuration extends laterally away from the base, thereby extending said load- receiving portion laterally outboard of the base, and wherein the wing unit is demountable from the base and adapted to be rotated through substantially ninety degrees and supported by the base in a transport configuration in which the wing unit does not extend laterally away from the base.

By"laterally away from the base"it is meant that wing unit extends laterally away from the side edges. This provides additionally load-receiving portion, than cannot be achieved with conventional width loading decks.

By"transport configuration"it is meant that the configuration is suitable for both transport and storage.

By way of example, several embodiments of the invention are described in more detail hereinafter with reference to the accompanying drawings.

For the sake of brevity and descriptive convenience, in the following description functionally similar components appearing in more than one figure, bear common reference numerals in all of the figures and their initial description made in relation to an earlier met figure is generally not repeated in relation to a later met figure.

Brief Description of the Drawings Fig. 1 is a diagrammatic perspective view of a typical fixed deck (category 1) construction platform according to the invention when in use.

Fig. 2 is a diagrammatic perspective view of a partly retractable (category 3) construction platform according to the invention.

Fig. 3 is a diagrammatic plan view of a fixed deck (category 1) construction platform according to the invention with personnel decks shown in an in-use, extended configuration.

Fig. 4 is a diagrammatic plan view of the fixed shown in figure 3, but shown with the personnel decks laterally retracted into the transport configuration.

Fig. 5 is a detail plan view of a releasable latch on platform shown in Fig. 3.

Figs. 6 (a)- (c) comprises three views each of which is a diagrammatic cross-section of a construction platform according to Figs. 3 and 4 taken immediately inboard of the personnel deck fence panels.

Figs. 7 (a) and (b), are each views of a diagrammatic cross-section of a platform according to Figs. 3 and 4 taken immediately inboard of the personnel deck fence panels, wherein the personnel decks are demountable.

Fig. 8 illustrates, in more detail, an exemplary mode of securing the de-mountable personnel decks of figure 7 to the side beams.

Figs. 9 (a)- (c) comprises three views each of which is a diagrammatic cross-section of a partly retractable (category 3) platform otherwise according to figures 3 and 4 taken immediately inboard of the personnel deck fence panels, wherein the personnel decks are rendered laterally retractable.

Fig. 10 is a diagrammatic cross-section of a fixed deck (category 1) platform according to Figs 3 and 4 taken immediately inboard of the personnel deck fence panels appearing in those figures, but drawn in more detail and to a larger scale to depict a linear anti- friction bearing.

Fig. 11 is an end elevation of the linear anti-friction bearing appearing in Fig. 10, drawn to a larger scale than that of figure 10.

Fig. 12 is a view similar to Fig. 11 but showing the end of the linear anti-friction bearing opposite to the end seen in Fig. 11.

Fig. 13 is a sectional view of the linear anti-friction bearing taken on line 13-13 of Fig.

12 drawn to a reduced scale.

Fig. 14 is a cross-sectional view taken on line 14-14 of figure 13 drawn to a larger scale.

Fig. 15 is a view similar to Fig. 10 but showing a category 2 or 3 version of the invention.

Figs. 16 (a) and (b) comprise two views being detail end elevations of modifications of the Fig. 10 and 15 embodiments showing alternatives to the linear anti-friction bearings appearing in those figures.

Fig. 17 is a diagrammatic perspective view of a partly retractable (category 3) construction platform according an embodiment to the invention.

Fig. 18 is a reduced plan view of the partly retractable construction platform shown in Fig. 17.

Fig. 19 is an enlarged sectional view through section 19-19 in Fig. 18.

Fig. 20 is an exploded version of the enlarged sectional view through section 19-19 in Fig. 18.

Fig. 21 is a diagrammatic perspective view of a partly retractable (category 3) construction platform according to an embodiment of the invention, in an in-use configuration.

Fig. 22 is a diagrammatic perspective view of the construction platform shown in Fig.

21, in a transport configuration.

Mode of Carrying out the Invention The platform shown in Fig. 1 comprises a stationary base comprising two side beams 1, each of which is a single piece comprising a length of steel I-beam or the like, extending longitudinally of the platform, and a plurality of cross beams 2, each extending laterally of the platform from one side beam 1 to the other (only one of the cross beams is visible in the figure), secured to a floor 3 of a building under construction by means of four extendible struts 4 (only three of which are visible in the figure) extending from inboard portions of the side beams 1 to the next higher floor 5 of the building, and a loading deck 6 supported by the beams 1 and 2. The platform further comprises safety barriers

comprising gates 7 at the free end of the loading deck 6 and fences 8 extending along the side edges of an opposite end portion of the loading deck 6.

Insofar as it has been described above the construction platform of Fig. 1 is a fully conventional category 1 construction platform, except that in prior known platforms the fences 8 would extend to the gates 7.

It will be seen that the loading deck 6 may extend, in this instance, beyond conventional scaffolding 9, including walk-ways 10 and a mesh cladding 11, such as is frequently applied to the exposed surfaces of buildings under construction for the convenience and safety of workers on the building and the protection of ground level pedestrians from anything that may be accidentally let fall from the building. Such scaffolding is assembled from standardised components complying with a modular dimension, and the width of the platform base and the distance between the fences 8 comply with the module so that the scaffolding may be assembled around the platform without the need for non-standard scaffold components.

Thus, there is a load-receiving portion of the loading deck 6, which portion is outboard of the scaffolding 9, and, in accordance with the invention that portion is flanked on each side by personnel decks 12 (only one of which is visible in the figure), which are laterally retractable. Moreover, personnel deck fences 13,14 and 15 extend along the free edges of the personnel decks 12 and are laterally retractable therewith. Each of the personnel deck fences may comprise posts and rails of hollow rectangular section supporting a sheet metal fence panel. Each personnel deck 12 and its respective deck fences 13,14 and 15 forms a laterally extending"wing".

In other embodiments of the invention similar to that of Fig. 1 the personnel decks and their associated personnel deck fences are demountable rather than laterally retractable.

Thus, as is made clear by Fig. 1 a workman 16 may stand in comparative safety on one or other of the personnel decks 12, when in place or not retracted as the case may be, to supervise the deposition of a wide crane load 17 onto the load-receiving portion of the

loading deck 6. Also, it makes it easier for the workman 16 to walk around wide loads and undo slings.

The attachment of the personnel decks 12 to the side beams and/or the loading deck and their support thereby is exemplified in subsequent drawings. It is sufficient to say at this time that when the personnel decks and their safety fences are either demounted or laterally retracted the maximum width of the construction platform is reduced for transport purposes to or near the width of conventional platforms.

Fig. 2 depicts a partly retractable (category 3) construction platform according to the invention. Once again it is conventional but for the presence of demountable or laterally retractable personnel decks 12 and the personnel deck fences 13, 14 and 15.

Thus the definitive difference between the embodiments of Fig. 1 and 2 is a conventional variation that converts the platform from a category 1 platform to a category 3 platform, that is to say renders the platform partly retractable. The variation is that each of the longitudinally extending, one-piece side beams 1 of Fig. 1 are replaced by two-piece side beams comprising a fixed base piece 21 and a moveable deck piece 23 that is roller mounted in conventional manner to the base piece 21 to render the deck piece 23 longitudinally retractable relative to the base piece 21. The base pieces 21 of the side beams project only a short distance beyond the edge of the floor 3 and are braced by lateral bracing 22 disposed outboard of the floor 3 and secured to the undersides of the base pieces 21.

Thus, in this category 3 embodiment, the loading deck 6, gates 7 and personnel deck fences 13,14 and 15, which are supported by the moveable deck pieces 23 of the side beams and the cross-beams extending therebetween (not visible in Fig. 2), are therefore also longitudinally retractable, at least to the extent where the gates 7 are substantially in register with the outboard ends of the base pieces 21 of the side beams. Of course, before such longitudinal retraction of the loading deck 6 may be effected, the personnel decks 12 and their associated fences 13,14 and 15 must be demounted or laterally retracted.

Fig. 3 is a diagrammatic plan view of a fixed deck (category 1) construction platform according to the invention with the personnel decks 12 shown in the in-use, extended configuration and wherein lateral retraction of the personnel decks 12 and their associated personnel deck fences 13, 14 and 15 may be effected by bodily translation.

In this, and other preferred embodiments of the invention, each personnel deck 12 and its associated personnel deck fences 13,14 and 15 may be a pre-fabricated, integrated personnel deck unit 29 in the form of a rigid, open-topped, three-sided box.

When extended as shown in Fig. 3, each said personnel deck unit 29 may be braced by releasable latches 24 affixing the units to fence posts 25 extending rigidly upwardly from the respective side beams 1.

Fig. 4 is a diagram similar to Fig. 3, illustrating the same embodiment of the invention, but shown with the personnel deck units 29 laterally retracted into the transport configuration.

In alternative versions of each embodiment of the invention illustrated and described herein, the personnel deck units may be collapsible, so as to enable them to take up less space during transport. That is to say, the personnel deck fences may be demountable from the personnel deck and/or each other, or, preferably, individually hinged to the personnel deck and/or each other, to enable them to be folded against each other and down onto the deck. In either event, suitable braces or latches would be provided to hold the fences in the rigid configuration of units 29, when in the in-use configuration.

Fig. 5 is a detail plan view of a releasable latch 24 (referred to in relation to Fig. 3) temporarily securing a personnel deck fence panel 13 of a laterally retractable, personnel deck unit 29 to a fence post 25. It comprises a lug 26 on the post and a nut and bolt fastener 27 extending through the lug 26 and the fence panel 13. In other embodiments of the invention the latch 24 may be replaced by other quick release fasteners, for example a swing hook engagable with an eye or stud, a slidable barrel bolt and socket or other conventional releasable coupling device or latch.

Figs. 6 (a)- (c) comprises three views each of which is a diagrammatic cross-section of a construction platform according to Figs. 3 and 4 taken immediately inboard of the personnel deck fence panels 15 appearing in those figures, wherein the personnel deck units 29 are rendered laterally retractable by way of bodily translation. The Fig. 6 platform includes two personnel deck units 29. View (a) shows the personnel deck units 29 in the fully laterally retracted transport configuration, view (b) shows one of the personnel deck units 29 (the right hand one as seen in the figure) in a fully extended in- use configuration and the other unit 29 in a partly extended configuration and view (c) shows the personnel deck units 29 in a fully extended in-use configuration. The translation of the personnel deck units 29 from one configuration to another is facilitated by linear anti-friction bearings 28 interposed between the respective personnel deck units 29 and the loading deck 6 and side beams 1.

An exemplary embodiment of the linear anti-friction bearings 28 is described in more detail hereinafter with reference to figures 10 to 14.

Fig. 6 illustrates a fixed deck category 1 platform, but it would be equally illustrative of category 2 and 3 embodiments of the invention if the side beams 1 of the drawing were deemed to be representations of moveable deck pieces 23 of the side beams of category 2 and 3 versions of the invention.

Fig. 7 comprises two views (a) and (b), each of which is a diagrammatic cross-section of a platform according to Figs. 3 and 4 taken immediately inboard of the personnel deck fence panels 15 appearing in those figures, wherein the personnel deck units 29 are demountable. View (a) shows the personnel deck units 29 in the fully laterally retracted transport configuration. View (b) shows one of the personnel deck units 29 being lifted to its in-use configuration wherein it may be re-secured to one of the side beams 1. The personnel deck fence panels 13 and 15 at respective ends of the deck units 29 (not seen in this sectional view) may be provided with lifting eyes to connect to crane slings.

Fig. 7 illustrates a fixed deck category 1 platform, but it would be equally illustrative of category 2 and 3 embodiments of the invention if the side beams 1 of the drawing were

deemed to be representations of the moveable deck pieces 23 of the side beams of category 2 and 3 versions of the invention.

Fig. 8 illustrates, in more detail, an exemplary mode of securing the de-mountable personnel deck units 29 of Fig. 7 to the side beams 1.

Fig. 8 comprises two views (a) and (b). View (b) is a diagrammatic plan view of a mid- portion of a de-mountable personnel deck unit 29 mounted to a side beam 1 of a fixed deck (category 1) embodiment of the invention. View (a) is a cross-section taken on line a-a of view (b). As shown, the personnel deck unit 29 is securable to the top flanges of the side beam 1 by a double line of bolts 31 extending through the beam flanges and a longitudinal edge margin of the personnel deck 12.

For preference the nuts engaged by the bolts 31 are welded to the undersides of the beam flanges to register with pre-formed bolt clearance holes in the personnel deck 12.

In other embodiments relatively loose fitting plug and socket couplings may be provided to enable the personnel deck units to be simply lowered into engagement with the main part of the platform and demounted simply by being lifted upwardly therefrom.

Fig. 8 illustrates a fixed deck category 1 platform, but it would be equally illustrative of a category 2 or 3 embodiment of the invention if the single piece side beam 1 appearing in the figure were deemed to be a moveable deck piece 23 of the two piece side beams described with reference to Fig. 2.

Fig. 9 comprises three views (a), (b) and (c) each of which is a diagrammatic cross- section of a partly retractable (category 3) platform otherwise according to figures 3 and 4 taken immediately inboard of the personnel deck fence panels 15 appearing in those figures, wherein personnel deck units 29 are rendered laterally retractable by way of bodily rotation about a longitudinally extending hinge line 30.

View (a) shows the personnel deck units 29 in the fully laterally retracted transport configuration, view (b) shows the personnel deck units 29 in a partly retracted configuration and view (c) shows the personnel deck units 29 in a fully extended in-use configuration.

The hinge lines 30 may be defined by lines of butt hinges (not shown) with their leaves secured to the personnel decks 12 and loading deck 6 respectively or by a piano hinge extending longitudinally of those components. Manual rotation of the personnel deck units may be facilitated by detachable lever handles (not shown) engagable with the deck units.

Fig. 9 illustrates a retractable deck (category 2 or 3) platform, but it would be equally illustrative of a category 1 embodiment of the invention if the two piece side beams 21 and 23 of the figure were replaced by a single piece side beam 1 with the hinges positioned to suit.

Fig. 10 is a diagrammatic cross-section of a fixed deck (category 1) platform according to figures 3 and 4 taken immediately inboard of the personnel deck fence panels 15 appearing in those figures, but drawn in more detail and to a larger scale, to show a linear anti-friction bearing 28, being first referred to in relation to Fig. 6.

Fig. 11 is an end elevation of the linear anti-friction bearing 28 appearing in Fig. 10, drawn to a larger scale than that of Fig. 10.

Fig. 12 is a view similar to Fig. 11 but showing the end of the linear anti-friction bearing 28 opposite to the end seen in Fig. 11.

Fig. 13 is a sectional view of the linear anti-friction bearing 28 taken on line 13-13 of Fig. 12 drawn to a reduced scale.

Fig. 14 is a cross-sectional view taken on line 14-14 of Fig. 13 drawn to a larger scale.

Fig. 15 is a view similar to Fig. 10 but showing a category 2 or 3 version of the invention.

The platform illustrated by Figs. 10 comprises two side beams 1, a loading deck 6, two personnel deck units 29 and four linear anti-friction bearings 28 interposed between the personnel deck units 29 and the deck 6. The four bearings 28 are disposed with at least two to each personnel deck unit 29. They are spaced apart longitudinally of the respective units and extend laterally thereof.

As may be seen from Figs. 11 to 14, each bearing 28 includes a long ball race 32, a short ball race 33 and two rows of ball bearings 34 trapped between the two races. The long ball races 32 are welded or otherwise affixed to the undersides of the personnel decks 12 and the short ball races 33 are fixed to the upper flanges of the side beams 1 or to the loading deck 6 if it overlaps the side beams. Thus it will be apparent that the personnel deck units may readily move laterally of the construction platform along with the long races 32. To facilitate such movement the inner ends of the long races 32 may be supported from the deck by wheels 35 rotatably mounted on the long races 32 near their ends remote from the short races 33.

The balls 34 are prevented from escaping from the ends of the short race 33 by retainer plates 35 fixed thereon, and the long race 32 is prevented from running off the short race by means of an end plate 36 thereon.

In other embodiments balls 34, may be replaced by rollers.

Figs. 10 illustrates a fixed deck category 1 platform, but it would be equally illustrative of a category 2 or 3 embodiment of the invention if the single piece side beam 1 appearing in the figure were deemed to be a moveable deck piece 23 of the two piece side beams described with reference to figure 2. Such an arrangement is shown in figure 15, which requires no further description herein, except to draw attention to the fact that the linear anti-friction bearings 28 overlie only one flange of moveable side beam pieces 23, so as to avoid fouling the base piece 21 when longitudinally retracted.

Fig. 16 comprises two views (a) and (b) being detail end elevations of modifications of the figures 10 and 15 embodiments showing alternatives to the linear anti-friction bearings appearing in those figures.

View (a) shows two angle-sectioned rails 36 fixed to, and extending laterally of, the personnel deck 12, in place of the long race of a linear anti-friction bearing, a pair of rollers 37, being the foremost of at least two such pairs spaced one behind the other, and a pedestal 38 and axle assembly for the support of the rollers 37 from the side beam 1.

View (b) shows a functionally similar arrangement wherein an inverted T-section rail 39 projects between and below rollers 37, which are independently supported from the side beam 1 by pedestal 40 and stub axle assemblies.

Figs. 16 illustrates a fixed deck category 1 platform, but it would be equally illustrative of a category 2 or 3 embodiment of the invention if the single piece side beam 1 appearing in the figure were deemed to be a moveable deck piece 23 of the two piece side beams described with reference to figure 2.

Fig. 17 is a diagrammatic perspective view of a partly retractable (category 3) construction platform according to the invention. Once again it is conventional but for the presence of demountable personnel decks 12 and the personnel deck fences 13,14 and 15, in a similar fashion to that of the embodiment shown in figure 2. Each personnel deck 12 and its respective deck fences 13,14 and 15 forms a laterally extending wing 40. Like the embodiment of Fig. 2, it comprises two-piece side beams comprising a fixed base piece 21 and a moveable deck piece 23 that is roller mounted in conventional manner to the base piece 21 to render the deck piece 23 longitudinally retractable relative to the base piece 21. The base pieces 21 of the side beams project only a short distance beyond the edge of the floor 3 and are braced by lateral bracing 22 disposed outboard of the floor 3 and secured to the undersides of the base pieces 21.

Fig. 18 is a reduced plan view of the partly retractable construction platform shown in Fig. 17.

Fig. 19 is an enlarged sectional view through section 19-19 in Fig. 18. Each wing 40 is demountably connected to a respective moveable deck piece 23 via bolt and nut fasteners 41 and bracket 42.

Fig. 20 is an exploded version of the enlarged sectional view through section 19-19 in Fig. 18.

Figs. 21 and 22 depicts a further embodiment of a partly retractable (category 3) construction platform according to the invention. In this embodiment a single wing unit 43 is used, rather than two demountable wings 40 as shown in earlier embodiments.

Wing unit 43 has a single deck 44 and deck fences 13,14 and 15. In this particular embodiment, wing deck 43 is shown in an"in use configuration"in Fig. 21. The wing unit 43 is removably fastened to moveable deck pieces 23 by bolt and nut fasteners (not shown) in a similar fashion to the earlier described demountable wing embodiments.

The wing unit 43 has sides which extend laterally away from the moveable deck pieces 23. The construction platform is provided with a ramp 45 between wing unit 43 and floor 3. For purposes of transport and storage, the wing unit 43 may be unfastened from moveable deck pieces 23 and spun around through ninety degrees, to fit inside fences 8 of the stationary base as shown in Fig. 22. Whilst this embodiment is described in relation to a single wing unit 43 being used on a partly retractable (category 3) construction platform, it should be understood that single wing unit 43 could also be used with other types of platform.

The foregoing describes only some embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention.

The term"comprising" (and is grammatical variations) as used herein is used in the inclusive sense of"including"or"having"and not in the exclusive sense of"consisting only of".