WO2002086256A1

WO2002086256A1 - A moveable screen

Info

Publication number: WO2002086256A1
Application number: PCT/AU2002/000506
Authority: WO
Inventors: Joseph John Cox; Emilio Rosati
Original assignee: Formula One Self Driving Screens Pty Ltd
Priority date: 2001-04-24
Filing date: 2002-04-24
Publication date: 2002-10-31
Also published as: AUPR456201A0

Abstract

The invention relates to a moveable screen (10) comprising a screen, a first support (13), a second support (12) secured with respect to the screen, hoist means (14) acting between the first and second supports (13 and 12), to move the second support (12) towards or away from the first support (13), and a fixed support (24) for holding the first support (13) so that when the hoist means (14) is operated the screen is moved up or down with respect to the fixed support (24). The invention provides a self-moving screen that does not require the use of other lifting devices such as cranes to move the screens vertically which would be the case with fixed non-movable screens.

Description

A MOVEABLE SCREEN

This invention relates to a moveable screen, and in particular to the means of moving the screen with respect to a fixed support.

The invention has numerous applications. However it is particularly suited to safety screens which are used during the construction of multi story buildings. The invention will be described primarily in relation to this application, but it should be understood that the invention is in no way limited to this particular use. For example, the safety screens may be used in other applications where a moving screen would be useful. Modifications and variations such as would be apparent to a skilled addressee are deemed within the scope of the present invention.

Multi story buildings are normally constructed one floor or one stage at a time using concrete casting techniques. This building process results in the construction of supporting columns and the next floor on top of a previously completed stage. Work is then carried out on the upper most stage to create the next floor while at the same time work is carried out on lower stages to complete construction by locating external cladding window frames and windows. As this work is being carried out, there is a need to provide safety screens on the external surface of the building. These screens enable work at the edge of the building including the location of external cladding but provides security for personnel and prevents objects falling from the building.

These safety screens are normally fixed in position and require cranes to move them up the building as the various stages are completed and the building advances upwardly. No work can commence on the upper stage until the safety screens are in place. Normally, the safety screens are lifted when a floor or stage is complete with external cladding and work commences on a new floor. The use of cranes is time consuming and costly. No work can commence on the upper stage until the safety screens are installed around the whole perimeter of the building, so construction time is lost while the screens are moved into position.

The further problem with the existing safety screen systems is the need to provide a variety of screen widths. Screens are required to fit the whole perimeter of the building which normally require the manufacture of individual screens to suit a particular building. In addition, the cross sectional shape of the building may vary from one level to the next requiring different width screens at different levels.

It is an aim of this invention to provide an improved moveable screen that does not require the use of cranes to move the screens from one level to the next. It is also an aim of the invention to provide a moveable screen that is adjustable in width to provide flexibility in the location of the screen to a building.

In broadest form, the invention is a moveable screen comprising: a screen a first support a second support secured with respect to said screen, hoist means acting between said first and second supports to move said second support towards or away from said first support, and a fixed support for holding said first support so that when said hoist means is operated said screen is moved up or down with respect to said fixed support.

The fixed support will vary depending on the application. In the case of multi story buildings, the fixed support will be a floor or stage of the building or a beam attached to a floor or stage.

The hoist means may comprise a number of different mechanisms including electric motors driving threaded shafts, hydraulic rams, pulley and cable systems, a motorised winch drum and cable system or any other mechanism which enables the second support to be lifted or lowered with respect to the first support.

The screen may comprise steel mesh but other screen elements such as flexible netting or solid panels may also be used.

The height of the screen will vary depending on the application. In the case of multi story buildings, the height of the screen is sufficient to cover at least two stages of floors. This provides a safety screen for the upper stage where new form work is being located for casting of the next floor. The screen can be moved upwardly as required by operation of the hoist means. Preferably, this occurs prior to or as the next stage is being cast. Clearly, this avoids the need to use a crane to relocate the screen. Any one building may use a number of individual moveable screens which can all independently be lifted as required.

At the stage where the moveable screen has been raised to the extent where the second support is adjacent to the first support and can be raised no further, the screen is then secured with respect to the fixed support so that the first support can be driven upwardly with respect to the second support. In the case of a multi story building, this can be accomplished once an upper stage is finished to the point where it can become or support a new fixed support. In this case, the first support is either lifted upwardly or driven upwardly, depending on the type of hoist means used, where upon it is fixed with respect to the next level. This level then becomes the fixed support and the screen can then be released so that it can move freely with respect to the building or fixed support. In this way, the moveable screen can continue to move upwardly through the simple relocation of the fixed support. The screen may comprise a frame with screening material attached. The screen or frame may also carry one or a number of secondary screens which can be used to extend both the height and width of the moveable screen.

The screen may contain one or a number of laterally or vertically extending screens which enable the width of the screen to be increased. These extending screens can be manually deployed and pulled out to the width as required or the height required. They may comprise a number of smaller frames slideably located within the screen. These extending screens can almost double the width of the screen when fully extended and significantly increase the height of the screen.

The use of extending screens enables the moveable screen to be optimally positioned with respect to fixing points on a building and then the width or height to be adjusted to take into account existing columns or the location of required openings for access to the floors covered by the screen. Adjacent screens can be positioned at the best fixing points on the particular stage or floor with the extending screens then pulled out as required to fill the remaining gaps between adjacent screens or building structures.

A second screen can be attached with respect to the first screen and may be used to extend either downwardly or upwardly to increase the height or vertical length of the screen. The second screen is preferably attached with respect to the first screen with independent hoist means that can act to raise or lower it with respect to the first screen.

The second screen may also have a plurality of laterally extending screens which are used to increase it's width in a manner which is similar to that described above for the first screen. In order for the invention to be fully understood, a preferred embodiment will now be described. However, it should be realised that the scope of the invention is not to be confined or restricted to this particular embodiment. The embodiment is illustrated in the following drawings in which:

Figures 1 and 2 show a moveable screen,

Figures 3 and 4 show cross sectional views of the moveable screens shown in Figures 1 and 2,

Figure 5 is a side view showing the means of attaching the moveable screen to a building,

Figure 6 shows a moveable screen with extending screens,

Figures 7 and 8 show a moveable screen incorporating an additional vertically moving screen, and

Figures 9 and 10 show sliding connectors that attach to the frame of a moveable screen.

Figure 1 shows a moveable screen 10. The basic elements of the moveable screen 10 are a screen that comprises a frame 11 with a screening material such as attached wire mesh, a second support, which in this embodiment is referred to as a motor beam 12, a first support, which in this embodiment is referred to as a support beam 13 and a hoist means comprising an electric motor 14.

The motor beam 12 is secured to a fixed support. In this embodiment, a pair of beams are anchored to the floor of a building so that they extend over the edge of the floor. The motor beam 12 is in turn fixed to the beams. The electric motor 14 drives a pair of threaded spindles 17 the ends of threaded spindles locate through threaded apertures within the support beam 13. Operation of the motor 14 causes the threaded spindles 17 to rotate and therefore the support beam 13 to move along the threaded spindle 17 in a direction that is determined by the direction of rotation of the threaded spindles 17.

Figure 1 shows the maximum separation between the motor beam 12 and the support beam 13. Figure 2 shows the minimum separation between the motor beam 12 and support beam 13 after operation of the motor 14. As can be seen from Figure 2, support beam 13 has moved along the threaded spindle 17 and in turn lifted the moveable screen 10 with respect to the stationary motor beam 12. The moveable screen 10 can be raised and lowered with respect to the stationary motor beam 12.

Figures 3 and 4 show cross sectional views of the moveable screen 10 and show both the motor beam 12 (Fig 3) and the support beam 13 ( Fig 4).

Referring to Figure 3, the motor 14 drives gearboxes 19 which in turn drive the threaded spindles 17.

Part of the frame 11 comprises U-shaped channels 20 within which the motor beam 12 locates. As seen in Figure 4, the support beam 13 also locates within the U-shaped channel 20. The U-shaped channel 20 has a plurality of apertures spaced along its length within which the tongue of latch 16 locates to secure the support beam 13 with respect to the channel 20. This fixes the support beam 13 with respect to the frame 11.

As seen in both Figure 3 and Figure 4, the frame 11 includes a pair of columns 21 which are attached to the U-shaped channels 20. The attachment is by a plurality of lugs 22 that are spaced along the length of the columns 21 which forms a series of elongate slots or apertures between the column 21 and the U-shaped channel 20 and adjacent lugs 22.

In addition to securing the motor beam 12 with respect to the building, additional sliding connections 23 are provided that attach to the columns 21. Preferably, horizontal beams are used to form the connections between the motor beam 12 and the columns 21. This is illustrated in Figure 5 where the horizontal beams 24 are secured to the floor 25 of selected stages of the building. The lower beam 24 connects directly to the motor beam 12. On the same level, the beam 24 is also used to connect to the column 21.

Sliding connectors 23, that attach to the column 21, are used to allow vertical sliding movement of the column 21 with respect to the connection 23 while at the same time providing a connection that holds the frame 11 to the building that also resists rotation. As seen in Figure 5, Figure 9 and Figure 10, the sliding connections 23 each comprise a pair of side plates 34 that locate either side of the column 21. Each side plate has a flange 35 that locates in front of the column 21. The flanges 35 only extend part way across the columns 21 to provide a gap through which the lugs 22 may pass.

Each of the side plates 34 attach to a mounting block 37. In a disassembled form, each of the side plates 34 are put in place around the column 21 with the mounting block 37 in place. Threaded fasteners are then used to secure the side plates 34 to a mounting block 37 which then ensures that the sliding connectors 23 are securely attached to the columns 21.

Each of the sliding connectors 23 may be provided with a pivoting bar 38 which is engaged by the lugs 22 as they move upwardly with respect to the sliding connectors 23. The upward movement of the lugs 22 rotates the pivoting bar 38 upwardly to allow the lug 22 to pass. After it passes, the pivoting bar 38 falls back to its horizontal position. The pivoting bar 38 is prevented from rotating downwardly and therefore will engage the lugs 22 if they move downwardly and restrain them from passing. This provides a safety feature which will arrest any uncontrolled downward movement of the screen 10.

Referring to Figure 9 and Figure 10, the lower sliding connector 23 has a pin 39 attached to the mounting block 37 that locates within an aperture 40 that is in the end of the horizontal beam. Figure 10 shows the horizontal beam 24 separated from the sliding connector 23 and therefore shows the aperture 40. This enables the sliding connector 23 to be easily attached to the horizontal beam 24. It also provides sufficient rotation of the sliding connector 23 with respect to the beam 24 to enable the beam 24 to be positioned at a angle if necessary with respect to the frame 11. This allows the beam 24 to be placed in the best position which may not always be at 90 degrees with the respect to the frame 11.

As shown in Figures 5 and 9, a second upper sliding connector 23 is attached to column 21. It is connected to the lowest sliding connector 23 and beam 24 via struts 26. The struts 26 are adjustable on length and have pin connections that allow attachment to both the mounting blocks 37 and both sliding connectors 23 and the beam 24. The use of two sliding connectors 23 provide additional resistance to rotation of the frame 11 about a horizontal axis that is parallel to the frame 11.

Further, an additional beam 24 may be placed on an upper floor 25 which also connects to the column 21 via a sliding connector 23. This additional connection also resists any rotational movement of the frame 11.

The side plates 34 have apertures 41 which align with apertures 27 in the column 21. A pin (not illustrated) is inserted in the apertures 41 and 27 which fix the sliding connectors 23 with respect to the column 21. This fixing of the sliding connectors 23 allows the motor and support beams 12 and 13 to be disconnected from the frame 11 when they are moved to different levels. This is further explained below.

When the support beam 13 reaches its uppermost position where it is close or adjacent to the motor beam 12, as seen in Figure 5, the motor beam 12 needs to be repositioned to allow further upward movement of the moveable screen 10. In the position shown in Figure 5, locking pins are inserted through the sliding connections on columns 21. Columns 21 are provided with a plurality of apertures 27 which enables the moveable screen 10 to be locked in position. The motor beam 12 can then be disconnected from the horizontal beams 24 and moved to a higher stage. This is achieved by rotating the threaded spindles 17 in a direction that moves the motor beam 12 upwardly with respect to the support beam 13. Horizontal beams 24 on an upper stage are then secured to the motor beam 12. Locking pins are then removed from the apertures 27 in the columns 21 so that the screen 10 is free to move upwardly.

As seen in Figure 5, the U-shaped channels 20 are provided with a plurality of slots 28 into which tongues of latches 16 locate. This secures the support beam 13 with respect for the frame 11. Further adjustment of the vertical position of the screen 10 can be achieved by relocating the latches 16 of the support beam 13 into different slots 28.

The frame 11 further comprises a frame generally shown as 30 in figures three and four which is secured to the U-shaped channels 20. The frame 30 carries on its external surface a wire mesh which forms the main barrier or screen. The frame also carries a number of extending screens or sliding frames which are capable of sliding into and out of the frame 30. These sliding frames 31 are shown in Figure 6. The frames 31 slide laterally into and out of frame 30. The right hand side of Figure 6 shows all of the frames 31 extended to the maximum extent. However, the frames 31 can be pulled out only to the extent required as illustrated on the left hand side in figure 6. This can be to avoid a particular structure on the building such as a column, or to provide an access for the supply of equipment and material to that particular level. As the moveable screen 10 is raised, the moveable frames 31 can be repositioned as required once the screen 10 reaches its new position.

The frames 31 are lightweight and can be manually moved. The frame 30 is provided with a plurality of channels within which the frames 31 slide. Each of the frames 31 are also covered in wire mesh.

Figures 7 and 8 illustrate a vertically moveable screen 33 that can be raised or lowered from behind the frame 30. This enables the height of the screen 10 to be varied. As seen in Figure 7 the moveable screen 33 is positioned within the U-shaped channels 20 between the outer frame 30 and the motor and support beams 12 and 13. Separate hoist means (not drawn) is used to raise and lower the frame 33 with respect to the U-shaped channels 20. The moveable screen 33 is also provided with sliding frames 31 which extend outwardly as shown in Figure 8. Both the frame 30 and moveable screen 33 will raise together when the motor 14 is operated.

The width of the moveable screens 10 can be adjusted according to the needs of each individual building. Preferably, a series of standard widths are provided, which in combination with the extending screens, enable any building to be fitted with a safety screen around its circumference.

As will be seen from the above description, the invention provides a unique safety screen system which does not need the use of cranes for repositioning the screens. This means that the screens can be moved quickly and efficiently at times which will not disrupt normal building schedules. For example, the screens can be moved prior to a concrete pour so that they are in position ready for work to commence on the new level. This provides a significant cost and time saving.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A moveable screen comprising: a screen, a first support, a second support secured with respect to said screen, hoist means acting between said first and second supports to move said second support towards or away from said first support, and a fixed support for holding said first support so that when said hoist means is operated said screen is moved up or down with respect to said fixed support.

2. A moveable screen according to claim 1 wherein said first support is slideably secured with respect to said screen.

3. A moveable screen according to either claim 1 or claim 2 wherein said screen comprises a frame with attached screening material.

4. A moveable screen according to any one of the preceeding claims further comprising a plurality of extending screens that are independently extendable or retractable with respect to said frame.

5. A moveable screen according to claim 4 wherein said extending screens extend horizontally from the sides of said screen.

6. A moveable screen according to claim 4 wherein said extending screens extend vertically from the top or bottom of said screen.

7. A moveable screen according to any one of the preceeding claims wherein said first and second supports each comprise a beam.

8. A moveable screen according to claim 7 wherein said second support is releaseably secured to said screen by a latch.

9. A moveable screen according to either claim 7 or 8 further comprising a pair of spaced guides having channels within which the ends of said first support beam locate to restrain movement of said screen with respect of said first support other than in the said direction of movement of said screen.

10. A moveable screen according to any of claims 7 to 9 wherein said hoist means comprises at least one threaded spindle that is rotateably mounted with respect to said first support and threadably engaged to said second support.

11. A moveable screen according to claim 10 wherein said hoist means comprises a pair of said spindles .

12. A moveable screen according to either claim 10 or 11 wherein said spindles are driven by an electric motor.

13. A moveable screen according to any one of the preceeding claims wherein said screen further comprises at least one vertical limit column, a sliding connector that attaches to said column and a second fixed support so that said column slides through said sliding connector.

14. A moveable screen according to claim 13 wherein said sliding connector allows movement of said column in one direction but restrains movement in the other direction.

15. A moveable screen according to either claim 13 or 14 further comprising a pair of spaced sliding connectors attached to said column.

16. A moveable screen according to any one of claims 13 to 15 wherein two vertical columns are provided.

17. A method of using a moveable screen according to any one of the preceeding claims comprising: operating said hoist means to raise said screen by moving said second support upwardly towards said first support, securing said second support to or with respect to said fixed support, releasing said first support from said fixed support, operating said hoist means so that said first support moves upwardly and away from said second support, securing said first support to a new fixed support , and releasing said second support from said fixed support.

18. A moveable screen substantially as herein described with reference to the accompanying drawings.

19. A method of using a moveable screen substantially as herein described with reference to the accompanying drawings.