AU2009311252B2

AU2009311252B2 - Scaffold system

Info

Publication number: AU2009311252B2
Application number: AU2009311252A
Authority: AU
Inventors: Joseph Sam Kang
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-11-04
Filing date: 2009-11-04
Publication date: 2014-06-26
Anticipated expiration: 2029-11-04
Also published as: AU2009311252A1; NZ592745A; WO2010051582A1

Abstract

A scaffold system (20) comprising a first main frame (22) having a first pair of generally parallel posts (24, 26), and a first ledger rail (28), the first ledger rail (28) extending between and being generally perpendicular to the first pair of posts (24, 26). The system (20) includes a second main frame (30) having a second pair of generally parallel posts (29, 31), and a second ledger rail, the second ledger rail extending between and being generally perpendicular to the second pair of posts (29, 31). The system (20) includes a first transom bar 50 extending between a primary post (24) of the first pair of posts (24, 26), and a primary post (29) of the second pair of posts (29, 31); a second transom bar extending between a secondary post (26) of the first pair of posts (24, 26), and a secondary post (31) of the second pair of posts (29, 31); wherein the transom bars 50 are pivotally connected to the posts (24, 26) with collars (40).

Description

WO 2010/051582 PCT/AU2009/001436 1 Scaffold system Field of the Invention The present invention relates to a scaffold system. In particular, the present invention relates to a modular scaffold system. Background of the Invention Construction workers are often exposed to dangerous conditions when working at height, where there may be a substantial risk of falling. During construction work, it is necessary to protect workers and site visitors from injury resulting from falling from significant heights. It is also necessary to protect workers and other persons from falling objects. On some building sites, workers are secured to lanyard lines extending between a harness and a fixed anchor point located on the roof or another structure. Whilst lanyard lines significantly reduce the risk of injury, worker mobility is significantly compromised and the worker is restricted to working within a given radius of the anchor point. This inconvenience may result in reduced productivity on the construction site. In addition, some building sites are not suitable for use with harnesses when there is no adequate rescue system in place in the event of a fall. Scaffolding is often used to provide workers with access to the various areas of a construction site in a safe manner, reducing the overall risk of the workers being injured, and providing access to each level of the work site. One disadvantage associated with scaffolding is that the installation times can be significant, which adds to the cost of the construction work. A further disadvantage is that the scaffolders who erect and dismantle the scaffolding may themselves be exposed to dangerous working conditions. Scaffolding is used on a majority of high rise building sites, and there are various scaffolding systems which typically utilise numerous components. However, many existing scaffold 2 Received 14 May 2010 systems are excessively complicated, requiring the scaffolders to stock numerous items for each installation. The inherent level of complication associated with such systems adds to the cost of erecting and dismantling the systems, and raises the risk of user error. In addition, more complicated scaffold systems necessitate specialised training for the scaffolders and contractors who operate them. Object of the Invention It is an object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages, or to provide a useful alternative to existing scaffold systems. Summary of the Invention In a first aspect, the present invention provides a scaffold system comprising: a first main frame having a first pair of generally parallel posts, and a first ledger rail, the first ledger rail extending between and being generally perpendicular to the first pair of posts, an upper end of each post has a male engagement formation which is engageable with a female engagement formation 'formed in a lower end of another corresponding post such that the posts are interconnectable end to end; a second main frame having a second pair of generally parallel posts, and a second ledger rail, the second ledger rail extending between and being generally perpendicular to the second pair of posts; one or more platform boards; a first transom bar extending between a primary post of the first pair of posts, and a primary post of the second pair of posts; and a second transom bar extending between a secondary post of the first pair of posts, and a secondary post of the second pair of posts, wherein the first and second transom bars have a generally L-shaped profile adapted to receive and support the platform boards. further wherein the first and second transom bars are pivotally connected to the posts with collars. Preferably each post includes a first tubular portion, a second tubular portion and a shaft having a first end secured within the first tubular portion, and a second end secured within the second tubular portion, wherein each collar is seated on one of the shafts between the Amended Sheet

.IPEA/AU

Received 14 May 2010 first and second tubular portions. A first washer is preferably located between each collar and the first tubular portion, and second washer is located between each collar and the second tubular portion. A first hole is preferably formed in an outer wall of each collar and a second hole is formed in each shaft, and a pin is insertable through the first and second holes to pivotally isolate the collar. The shaft is preferably secured to the first and second tubular portions by crimping. A base portion of each post is preferably engageable with a base jack which is supported by a vertically adjustable foot. Each base jack preferably includes double male projections and the base jack is adapted to engage with two of said posts. In a second aspect, the present invention provides a method of installing a scaffold system, the scaffold system having: a first main frame having a first pair of generally parallel posts, and a first ledger rail, the first ledger rail extending between and being generally perpendicular to the first pair of posts; a second main frame having a second pair of generally parallel posts, and a second ledger rail, the second ledger rail extending between and being generally perpendicular to the second pair of posts; a first generally L-shaped transom bar extending between a primary post of the first pair of posts, and a primary post of the second pair of posts; a second generally L-shaped transom bar extending between a secondary post of the first pair of posts, and a secondary post of the second pair of posts; the method including the following steps: pivoting the transom bars about collars located around a portion of the posts, such that the first main frame and second main frame move away from each other and remain generally parallel to each other; locking the collars relative to the posts when the first and second generally L-shaped transom bars are generally perpendicular to the ledger rails; and Amended Sheet

IPEA/AU

Received 14 May 2010 inserting a platform board between the first and second generally L-shaped transom bars such that ends of the platform board are supported by generally horizontal portions of the first and second transom bars. Brief Description of the Drawings A preferred embodiment of the invention will now. be described by 'Way of specific example with reference to the accompanying drawings, in which: Fig. 1 is a perspective view showing a single scaffold unit of a scaffold system; Fig. 2 is a partial sectional view showing a portion of a post of the scaffold system of Fig. 1; Fig. 3 is a schematic top view showing the unit of Fig. 1 in a flat packed configuration; Fig. 4 is a schematic top view showing the unit of Fig. 3 in a partially un-packed configuration; Fig. 5 is a schematic top view showing the unit of Fig. 3 in an unpacked configuration; Fig. 6 is a side view showing the scaffold system of Fig. 1 flat packed and stored in a pallet; Fig. 7 is a front view of the scaffold system- of Fig. 6; Fig. 8 is a front view of a scaffold system of a first embodiment; Fig.,9 is a front view of a scaffold system of a second embodiment; Fig. 10 is a front'view of a double spigot jack of the second embodiment; Fig. 11 is a front view of a coupler element of the second embodiment; Fig. 12 is a schematic front view showing the erection of the scaffold system of the second embodiment; and Fig. 13 is a schematic side view showing the'erection of the scaffold system of the second embodiment. Detailed Description of the Preferred Embodiments A scaffold system 20 is disclosed. The scaffold system 20 includes a plurality of independent units 21. Each unit 21 includes four vertical posts (24, 26, 29, 31) and.a plurality of interconnecting horizontal rails. Amended Sheet

IPEA/AU

Receivect 14 May 2010 As shown in Fig. 1, each unit 21 includes a first main frame 22 comprising a first vertical post or standard 24, and a second vertical post or standard 26. The first and second vertical posts 24, 26 are located at opposing ends of the first main frame 22. The vertical posts 24, 26 are generally right cylindrical tubes. A horizontal bar or ledger 28 extends between the Amended Sheet

IPEA/AU

WO 2010/051582 PCT/AU2009/001436 5 first and second vertical posts 24, 26. Accordingly, the first main frame 22 has a generally H-shaped profile. The horizontal bar 28 is welded or otherwise permanently attached to the vertical posts 24, 26. Each unit 21 of the scaffold system 20 includes a second main frame 30, having a configuration and dimensions which are generally the same as the first main frame 22. The second main frame 30 includes first vertical post or standard 29, and a second vertical post or standard 31. As depicted in Fig. 2, the vertical posts 24, 26 are generally hollow. A tube or shaft 60 having a smaller external diameter than the internal diameter of the post 24 is located within the posts 24. Near the lower end of the shaft 60, the shaft 60 is secured to the post 24 by crimping and/or with a bolt which passes through holes 62. Accordingly, the shaft 60 is rotationally secured relative to the post 24. An upper end of the shaft 60 is also secured to an extension portion 25 of the post 24 with crimping and/or a bolt which passes through holes 64 in the extension portion 25 and shaft 60. As such, the connection between the shaft 60 and the post 24 results in each post 24 having a diameter which steps down to a stepping region 61 of reduced diameter and steps up again to the full post diameter. Each of the vertical posts 24, 26 of the first and second main frames 22, 30 includes a rotating collar 40. Each rotating collar 40 is seated on the stepping region 61 of one of the vertical posts 24, 26. The collars 40 effectively sit around the shaft 60, and are able to pivot relative to the post 24, 26. The collars 40 each include a hole 42 which passes through two circumferentially opposing walls of the collar 40 for receiving a locking pin 44. A similar diameter hole is also formed in the shaft 60. Accordingly, the locking pin 44 may be selectively inserted through the collar 40 and the shaft 60 to lock the collar and hence the connected transom rail 50 relative to the first and second main frames 22, 30. A first washer 46 is placed beneath each collar 40 and a second washer 48 is placed above each collar 40. The washers 46, 48 assist the collar 40 to pivot smoothly.

WO 2010/051582 PCT/AU2009/001436 6 A first end 52 of a horizontal transom rail 50 is welded or otherwise permanently attached to the collar 40 of the first main frame 22. An opposing second end 54 of the transom rail 50 is also welded or otherwise permanently attached to the corresponding collar 40 of the second main frame 30. Accordingly, the transom rail 50 is able to pivot with the collars 40. A transom rail 50 is positioned at each end of the main frames 22, 30, and the transom rails 50 interconnect the first and second main frames 22, 30. The transom rails 50 have a generally L-shaped cross-sectional profile, and are fabricated from a length of steel or aluminium angle. At the base of each vertical post 24, 26, there is a female connector adapted to engage with a base jack 43 with a rectangular foot 41 for distributing the load of the scaffold system 20. The base jack 43 enables the foot 41 to be set at a desired vertical orientation to accommodate uneven or sloping terrain. The height of each vertical post 24, 26 is approximately 2 metres. At the upper end of the first and second vertical posts 24, 26 is a male projection 70 having an external diameter smaller that the internal diameter of the tube which makes up the first and second vertical posts 24, 26. Accordingly, the vertical posts 24, 26 of a first unit 21 can be interconnected end to end with similar vertical posts 24, 26 of a second unit 21 to define a vertical scaffold structure having a desired height. The installation of the scaffold system 20 will now be described. Each unit 21 of the scaffold system 20 is delivered to a construction site flat packed in a pallet 110 with the first and second main frames 22, 30 and interconnecting transom rails 50 preassembled. The flat packed units 21 are schematically depicted in Fig. 6 from a side view, and in Fig. 7 from an end view. The units 21 are generally delivered on a pallet 110 and are then lifted onto the construction site with a forklift or crane. When the units 21 are in the desired location on site, the units 21 are manually expanded from a generally flat configuration depicted in Fig. 3, by permitting pivoting of the collars 40 about the shafts 60. The units 21 gradually adopt the form of a parallelogram as shown in Fig. 4, and the units 21 continue pivoting until the final structural position which generally defines a rectangular form, as shown in Fig. 4.

WO 2010/051582 PCT/AU2009/001436 7 Each unit 21 is then connected to a base jack 43 which engages with the female coupling on the underside of each vertical post 24, 26. In the instance that the scaffold system 20 is being built into a continuous structure with multiple units 21 side by side, the structure may be made in two different ways, which are discussed below. In a first embodiment depicted in Fig. 8, the units 21 are arranged side by side, and each post 24, 26 is supported on a single base jack 43 and assembled. However, in between each pair of adjacent units 21, a space is provided and standard removable ledger rails 90 are then added to bridge the space between adjacent units 21. In a second embodiment depicted in Fig. 9, the units 21 are placed side by side, and supported on a double spigot jack 92. Each double spigot jack 92 has a single leg 94 supported by a foot 41, and a male double adaptor 96 for engaging two of the vertical posts 24, 26. In the second embodiment, when the units 21 are located side by side, a suitable coupler such as a double C coupler 98 as depicted in Fig. 11 is used to interconnect adjacent units 21. Such coupling increases the overall stability of the scaffold system 20. When the units have been installed and expanded, steel boards 100 are added. The steel boards 100 may be interconnected to each other with hinges. The transom rails 50 support the steel boards 100 which are used to support the weight of the workers. The L-shaped profile of the transom rails 50 inhibits the steel boards 100 moving longitudinally. The units 21 may be provided with fixed hand rails. However, the units 21 include connectors on the vertical posts 24, 26 which enable additional hand rails from existing scaffold systems to be connected. Fig. 12 is a side view depicting two scaffolders installing a second tier of units 21 to the system 20. Fig. 13 depicts the scaffolders installing the second tier from an end view, and expanding the unit 21. Advantageously, the scaffold system 20 can save up to 30 minutes of labour time to erect a WO 2010/051582 PCT/AU2009/001436 8 single unit 21 or scaffold bay. Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Claims

1. A scaffold system comprising: a first main frame having a first pair of generally parallel posts, and a first ledger rail, the first ledger rail extending between and being generally perpendicular to the first pair of posts, an upper end of each post has a male engagement formation which is engageable with a female engagement formation formed in a lower end of another corresponding post such that the posts are interconnectable end to end; a second main frame having a second pair of generally parallel posts, and a second' ledger rail, the second ledger rail extending between and being generally perpendicular to the second pair of posts; one or more platform boards; a first transom bar extending between a primary post of the first pair of posts, and a primary post of the second pair of posts; and a second transom bar extending between a secondary post of the first pair of posts, and a secondary post of the second pair of posts, wherein the first and second transom bars have a generally L-shaped profile adapted to receive and support the platform boards. further wherein the first and second transom bars are pivotally connected to the posts with collars.

2. The scaffold system of claim 1, wherein each post includes a first tubular portion, a second tubular portion and a shaft having a first end secured within the first tubular portion, and a second end secured within the second tubular portion, wherein each collar is seated on one of the shafts between the first and second tubular portions.

3. The scaffold system of claim 2, wherein a first washer is located between each collar and the first tubular portion, and second washer is located between each collar and the second tubular portion.

4. The scaffold system of claim 3, wherein a first hole is formed in an outer wall of each collar and a second hole is formed in each shaft, and a pin is insertable through the first and second holes to pivotally isolate the collar. Amended Sheet IPEA/AU Received 14 May 2010

5. The scaffold system of claim 3 or 4, wherein the shaft is secured to the first and second tubular portions by crimping.

6. The scaffold system of claim 1, wherein a base portion of each post is engageable with a base jack which is supported by a vertically adjustable foot.

7. The scaffold system of claim 6, wherein each base jack includes double male projections and the base jack is adapted to engage with two of said posts.

8. A method of installing a scaffold system, the scaffold system having: a first main frame having a first pair of generally parallel posts, and a first ledger rail, the first ledger rail extending between and being generally perpendicular to the first pair of posts; a second main frame having a second pair of generally parallel posts, and a second ledger rail, the second ledger rail extending between and being generally perpendicular to the second pair of posts; a first generally L-shaped transom bar extending between a primary post of the first pair of posts, and a primary post of the second pair of posts; a second generally L-shaped transom bar extending between a secondary post of the first pair of posts, and a secondary post of the second pair of posts; the method including the following steps: pivoting the transom bars about collars located around a portion of the posts, such that the first main frame and second main frame move away from each other and remain generally parallel to each other; locking the collars relative to-the posts when the'first and second generally L-shaped transom bars are generally perpendicular to the ledger rails; and inserting a platform board between the first and second generally L-shaped transom bars such that ends of the platform board are supported by generally horizontal portions of the first and second transom bars. Amended Sheet IPEA/AU