GB2486015A

GB2486015A - Folding platform safety unit

Info

Publication number: GB2486015A
Application number: GB1020399.0A
Authority: GB
Inventors: Gerard John Gallagher; Lewis Alberto Grijo Dos Santos
Original assignee: Turner Access Ltd
Current assignee: Turner Access Ltd
Priority date: 2010-12-02
Filing date: 2010-12-02
Publication date: 2012-06-06
Also published as: GB201020399D0; GB2491667A; GB201120662D0; WO2012072982A1

Abstract

A safety unit 10 for use with scaffolding or other structures, the unit having a worker's platform 11, a rear frame 12 on which a rear edge of the platform is pivotally mounted, and a pair of legs 13 extending downwardly below a front edge of the platform. The legs extend upwardly above the platform when the unit is in use to form part of a fall prevention barrier 14 which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate 26. The rear frame, platform, legs and barrier are foldable into a substantially parallel folded configuration when the unit is not in use for easy movement of the unit. A pair of hooks 15 carried by the rear frame hook over a substantially horizontal rail of the. U-shaped support means 16, supported from the rear edge of the platform, extend below the horizontal rail of the structure to prevent disengagement of the hooks from the horizontal rail. Also disclosed is a j-shaped spring loaded plunger 35 (figure 1) to lock a folding section, a clamping or fastening device 41 with two opposing circumferentially extending formations.

Description

SAFETY UNIT

This invention relates to a safety unit for use within a scaffolding structure or other structure to allow a worker to work in a position above the level of the decking or flooring of the scaffolding or other structure in complete safety.

It is an object of the present invention to provide an improved form of such a safety device which is stable and secure when in use.

Thus according to the present invention there is provided a safety unit for use with a scaffolding structure or other structure, the unit comprising:-a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of legs extending downwardly below a front edge of the platform when the platform is in use at an elevated substantially horizontal position above the ground or a working deck of the structure, the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate for access to the platform, the rear frame, platform, legs and barrier being foldable into a substantially parallel folded configuration when the unit is not in use for easy movement of the unit, a pair of hooks carried by the rear frame to hook over a substantially horizontal rail of the structure to secure the unit to and support the unit from the scaffolding structure when in use, and U-shaped support means supported from the rear edge of the platform which, when the platform is in its substantially horizontal working position, extend below the horizontal rail of the structure to prevent disengagement of the hooks from the horizontal rail.

The U-shaped support means comprises a plurality of U-shaped members carried by the rear edge of the platform so that as the platform is pivoted into its horizontal working position the members pivot into a position below the horizontal rail to prevent disengagement of the hooks from the horizontal rail.

The U-shaped members are preferably formed from spring steel one end of which is carried by the rear edge of the platform.

The legs and rear frame may be interconnected by one or more folding rails which extend therebetween and form part of the fall prevention barrier, said one or more folding rails having first and second parts and a folding joint intermediate said parts which can be locked against folding when the unit is in use by a spring-loaded plunger carried by one part which engages a locking formation (e.g. a hole) carried by the other part.

The spring-loaded plunger may be J-shaped with the shorter end of the J-shaped plunger engaging the formation and the other end of the J-shaped plunger carrying a handle which is depressed against a spring surrounding the plunger and which acts between the handle and said one part.

The barrier preferably includes an upper rail at the upper ends of the rear frame and legs and an intermediate rail located intermediate the upper rail and the platform, the portions of the upper rail and intermediate rail extending between the legs and the rear frame having folding joints intermediate their ends to allow the unit to fold and the platform being connected with the legs via a first pair of links each pivoted at one end on a respective leg and at the other end on an intermediate portion of the platform to allow the unit to fold to the substantially parallel folded configuration.

Preferably the positioning of the joints in the upper and intermediate rails and the location of the connection between the links and the intermediate portion of the platform allow the upper rail to fold downwardly and the intermediate rail and links to fold upwardly as the unit is folded.

Preferably connecting links extend between the axes of the folding joints of the intermediate rails and the axes of the connections of the first links with the platform.

The unit is preferably provided with a fastening device which engages an adjacent vertical component of the scaffolding structure to prevent tipping of the unit about the horizontal rail engaged by the pair of hooks.

The fastening device may conveniently comprise two circumferential extending embracing formations which extend partially around the vertical component in opposite directions, the formations being axially spaced relative to the vertical component to define therebetween a gap inclined at an angle relative to the axis of the vertical component through which the vertical component can pass in a direction perpendicular to the axis of the vertical component when the fastening device is twisted to said angle to align the gap and the vertical component.

The present invention also provides a safety unit for use with a scaffolding structure or other structure, the unit comprising a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of hooks carried by the rear frame to hook over a generally horizontal rail of the structure to secure the unit to and support the unit from the structure when in use, a pair of legs extending downwardly below a front edge of the platform when the platform is in use at an elevated generally horizontal position above the ground or a the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate between the upper portions of the legs above the platform for access to the platform, the rear frame, platform, legs and barrier being foldable into a generally parallel folded configuration when the unit is not in use for easy movement of the unit, the upper part of the legs and rear frame being interconnected by one or more folding rails which extend therebetween and form part of the fall prevention barrier, said one or more folding rails having first and second parts and a folding joint intermediate said parts which can be locked against folding when the unit is in use by a spring-loaded plunger carried by one part which engages a locking formation carried by the other part.

The present invention further provides a safety unit for use with a scaffolding structure or other structure, the unit comprising a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of hooks carried by the rear frame to hook over a generally horizontal rail of the structure to secure the unit to and support the unit from the structure when in use, a pair of legs extending downwardly below a front edge of the platform when the platform is in use at an elevated generally horizontal position above the ground or a the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate between the upper portions of the legs above the platform for access to the platform, the rear frame, platform, legs and barrier being foldable into a generally parallel folded configuration when the unit is not in use for easy movement and storage of the unit, the barrier including an upper rail at the upper ends of the rear frame and legs and an intermediate rail located intermediate the upper rail and the platform, the portions of the upper rail and intermediate rail extending between the legs and the rear frame having folding joints intermediate their ends to allow the unit to fold and the platform being connected with the legs via a pair of links each pivoted at one end on a respective leg and at the other end on an intermediate portion of the platform to allow the unit to fold to the generally parallel folded configuration.

The invention also provides a safety unit for use within a scaffolding structure or other structure comprising an elevated workers platform supported above a normal platform or flooring level of the structure by a support frame which hooks over a horizontal rail of the structure, a fall prevention barrier which surrounds the elevated workers platform, and a fastening device which engages an adjacent vertical component of the structure to prevent tipping of the unit about the horizontal rail of the structure, the fastening device comprising two circumferential extending formations which extend partially around the vertical component in opposite directions and are axially spaced relative to the vertical component to define therebetween a gap inclined at an angle relative to the axis of the vertical component through which the vertical component can pass in a direction perpendicular to the axis of the vertical component when the fastening device is twisted to said angle to align the gap and the vertical component.

According to a yet further aspect of the present invention there is provided a fastening device for securing a component to a tubular member, the fastening device comprising two circumferential extending formations which extend partially around the tubular member in opposite directions and are axially spaced relative to the tubular member to define therebetween a gap inclined at an angle relative to the axis of the tubular member through which the tubular member can pass in a direction perpendicular to the axis of the tubular member when the fastening device is twisted to said angle to align the gap and the tubular member.

The present invention will now be described, by way of example only, with reference to the accompanying drawings in which:-Figure 1 shows a front perspective view of a safety unit in accordance with the present invention; Figure 2 shows a side view of the unit of Figure 1; Figure 3 shows a plan view of the unit of Figure 1; Figure 4 shows a rear perspective view of the unit of Figure 1; Figure 5 shows a perspective view of the unit of Figure 1 partially folded; Figure 6 shows a side view of the partially folded unit of Figure 5: Figure 7 shows a perspective view of the unit of Figure 1 fully folded; Figure 8 shows a side view of the fully folded unit of Figure 7; Figure 9 shows a perspective view of the unit of Figure 1 in its working position on the decking of a scaffolding structure; Figures 10 to 16 show stages in the sequence of removing the safety unit from its working position on the scaffolding structure; Figures 17 shows a perspective view of a U-shaped support member used to secure the unit to the scaffolding structure; Figures 18 and 19 show details of a fastening device used to secure the un to an adjacent vertical scaffolding component; Figure 20 shows a perspective view of the linkages which connect the legs and rear frame in the unit of the present invention in a partially folded condition; Figures 21 to 26 show a top rail of the unit of the present invention and its locking mechanism, and Figures 27 and 28 show other uses of the fastening device of Figures 18 and 19.

Referring to the drawings, a safety unit 10 for use with a scaffolding structure 50 has a worker's platform 11 pivoted at a rear edge 1 Ia about an axis X on a bar 40 carried by the rear frame 12. A pair of legs 13 support a front edge 11 b of the platform when in use. The legs extend upwardly above the platform when the unit is in use to form part of a fall prevention barrier 14 which includes the rear frame and which completely surrounds the platform when the unit is in use. The barrier includes an openable gate 26 for access to the platform.

The rear framel2, platform 11, legs 13 and barrier 14 are foldable into a substantially parallel folded configuration when the unit is not in use for easy movement of the unit as shown in Figure 7 and 8. Clips 1 3a on legs 13 grip the rear frame 12 when the unit is folded.

The rear frame 12 has a pair of hooks 15 to hook over a substantially horizontal rail 51 of the structure 50 to secure the unit to and support the unit from the scaffolding structure 50 when in use. A support means in the form of a series of U-shaped spring steel support members 16 (see Figure 17) is supported at one end 17 from the rear edge 11 a of the platform 11. As will be described below, these support members 16 are arranged, when the platform is in its substantially horizontal working position, to extend below the horizontal rail 51 of the structure 50 to prevent disengagement of the hooks 15 from the horizontal rail.

The legs 13, which have access steps 18 extending between them, are interconnected with the rear frame 12 by an upper folding rail 19 and an intermediate folding rail 20 rail located intermediate the upper rail 19 and the platform 11. These rails form part of the fall prevention barrier 14 and have folding joints 19a and 20a intermediate their ends and are pivoted onto the legs and rear frame by pivot connections 19b and 20b respectively to allow the unit to fold as shown in Figures 7 and 8.

Platform 11 is connected with legs 13 via a first pair of links 21 each pivoted at one end on a bar 22 extending between the legs and at the other end on a bar 23 which extends through flanges 24 on an intermediate portion of the platform 11 to allow the unit to fold to the substantially parallel folded configuration shown in Figures 7 and 8. The joints 20a of bar 20 are connected with the pivot axis provided by bar 23 by links 25.

The fall prevention barrier 14 is completed by the horizontal bars 12a and 12b of the rear frame 12. The rear frame also has a further horizontal bar 12c below the platform 11. Gate 26 has an upper rail 26a and a lower rail 26b joined by vertical middle strut 26c and hinge post 26d. Hinge post 26d is pivoted on the upper part 1 3b of leg 13 by hinges 27. A spring-loaded latch 28 is provided on gate 26 to hold the gate in its closed position.

The folding joint I 9a of upper rail 19 includes a locking mechanism in the form of a J-shaped spring-loaded plunger 30 carried by one part 31 of rail 19 which engages a locking formation in the form of a hole 33 formed in the other part 32 of this rail. As can be seen from Figure 22, the shorter end 34 of the J-shaped plunger is engageable with the hole 33 and the other end of the J-shaped plunger carries a handle 35 which can be depressed (see arrow A) against a spring 36 which surrounds the plunger to disengage end 34 of the plunger 30 from hole 33 to allow rail 19 to fold at joint 19a. Spring 36 acts between the handle and the member 31 to bias the plunger towards the other member 32 and hence into engagement with hole 33 when the end 34 and hole 33 are aligned thus locking the rail 19 against folding.

As can be seen from Figure 2, the distance "x" between the bar 22 and the bar 23 is shorter than the distance "y" between the bar 40 and the bar 23. This xly ratio is also applied to the distances between the pivot axis of the folding joint 20a and the pivot connections with the legs 13 and rear frame 12 respectively. Again this ration x/y is also applied to the distances between the pivot axis of the folding joint I 9a and the pivot connections I 9b with the rear frame 12 and the legs 13 respectively. By reversing the x/y ratio for the length of the parts 31 and 32 of the upper rail 19 and by connecting the rail 20 to the platform via links 25 it is ensured that the upper rail folds downwardly and the intermediate rail 20 and the platform 11 fold upwardly thus reducing the overall size of the unit when folded whilst maintaining rear frame 12 and legs 13 generally parallel to each other. This folding movement is shown clearly in Figures 5 and 6 which show the unit in a partially folded condition.

The unit 10 is provided with a fastening device 41 which engages an adjacent vertical component 52 (see Figure 9) of the scaffolding structure 50 when the unit is in use to prevent tipping of the unit (see arrow B) about the horizontal rail 51 engaged by the pair of hooks 15. The fastening device, shown in more detail in Figures 18 and 19, is formed from an upper member 42 and a lower member 43 which are bolted together at 44. One end 42a, 43a of each upper and lower member 42, 43 is formed as a part cylindrical fastening formation which is riveted or otherwise secured to the lower end of rear frame 12 using fastening holes 44. The other end of each upper and lower member 42, 43 has a scaffolding pole embracing member 42b, 43b which is shaped to extend partially around the associated vertical scaffolding component 52. The embracing members 42b, 43b are spaced axially from each other and have angled upper and lower edges 42c, 43c which define between them an angled gap G best seen in Figure 16. This angled gap allows the vertical scaffolding component 52 to be introduced into and remove from within the embrace of members 42b and 43b only when the unit is tipped at the angle C shown in Figures 14 to 16.

Figure 9 shows the unit in its working position on the decking 45 of the scaffolding structure 50 with the hooks 15 engaging horizontal scaffolding member 51, the legs l0 supporting the unit from decking 45 and the fastening device 41 embracing the vertical component 52 of the scaffolding structure to stabilise the unit against tipping about the horizontal member 51. In this position the scaffolding worker can access the platform 11 via steps 18 and gate 26 and on closing gate 26 is fully surrounded by the fall prevention barrier 14 as previously described. This allows the worker to safely work at a level above decking 45 to, for example, begin the assembly or disassembly of the higher level of the scaffolding structure.

If the scaffolding worker wishes to remove the unit from its working position he goes through the sequence of moves illustrated in Figures 10 to 16.

Firstly the worker presses the handles 35 of the upper rail locking mechanisms inwardly as indicated by arrows A and then begins to fold the unit by moving the legs 13 towards the rear frame 12 as indicated by the arrow C in Figure 10. The geometry of the connections between the legs and the rear fame causes the legs to rise slightly clear of the decking 45 to assist in the folding of the unit. This folding of the unit is completed, as shown in Figure 11, when the clips 1 3a snap over the rear frame 12. As will be appreciated, as the unit folds, the platform 11 and thus the U-shaped support members 16 are pivoted about bar 40 so that when the unit is fully folded the U-Shaped members 16 are no longer below horizontal member 51 as can be seen in Figures 8and 11.

The unit is then raised, as indicated by arrow 0 in Figure 12, so that the hooks 15 disengage horizontal member 51 and then rotated about vertical member 52 on fastening device 41 as shown by arrow E in Figure 13. The unit is then rotated about a horizontal axis, as shown by arrow F in Figure 14 to align the vertical member 52 with the gap G of the fastening device as shown in Figure 16. The unit is then moved away from the vertical component 52 as shown by the arrow H in Figure 15 to completely disengage the scaffolding structure.

To mount the unit in its working position the above described sequence is reversed.

In an alternative arrangement (not shown) the unit can be made more compact by arranging that the legs are shorter and do not contact the ground or decking 45. This will require the remainder of the unit to be designed to support the weight of any workman standing on the platform without reacting this weight through the legs.

Figure 27 shows the fastening device 41 used to secure a vertical tube 12 to a vertical component 52 of the scaffolding structure. The tube 12 has a downwardly facing hook 15 which can be hooked over a horizontal component (not shown) of the scaffolding structure and a further upwardly facing hook 65 which can be used to support a further horizontal component of the scaffolding structure.

Figure 28 shows the fastening device 41 used to secure an angled stabilising leg 62 to a vertical component 52 of the scaffolding structure. Using this arrangement, the stabilising leg 62 can be connected with a higher part of the component 52 by a worker standing on the ground and rotating the fastening member 41 about a horizontal axis as indicated by arrow F in Figure 28. If required, stabilising leg 62 can be made more stable by connecting a horizontal tubular member (not shown) between a bottom portion of leg 62 and vertical component 52.

As can be seen from the above, the safety unit of the present invention provides a unit which is safe to use, stable when in use, compact when folded and easily secured to and removed from the scaffolding structure without the need to use any tools or additional clamps etc. Although the present invention has been described in relation to use with a scaffolding structure it is suitable for use with other structures such as permanent walkways found on offshore oil rigs or in chemical manufacturing plants which are guarded by railings and which have, for example, light fittings fixed above the walkways which require maintenance (e.g. bulb changing) from time to time. When used on such walkways, one man using the safety unit of the present invention can access the light fittings on his own without the need for a second man to hold a step ladder.

It will also be understood that the fastening device 41 can be used to secure a wide range of items to a tubular member and is applicable to many uses outside the

scaffolding field.

Claims

CLAIMS1) A safety unit for use with a scaffolding structure or other structure, the unit comprising a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of legs extending downwardly below a front edge of the platform when the platform is in use at an elevated substantially horizontal position above the ground or a working deck of the structure, the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate for access to the platform, the rear frame, platform, legs and barrier being foldable into a substantially parallel folded configuration when the unit is not in use for easy movement of the unit, a pair of hooks carried by the rear frame to hook over a substantially horizontal rail of the structure to secure the unit to and support the unit from the structure when in use, and U-shaped support means supported from the rear edge of the platform which, when the platform is in its substantially horizontal working position, extend below the horizontal rail of the structure to prevent disengagement of the hooks from the horizontal rail.
2. A unit according to claim I in which the U-shaped support means comprises a plurality of U-shaped members carried by the rear edge of the platform so that as the platform is pivoted into its horizontal working position the members pivot into a position below the horizontal rail to prevent disengagement of the hooks from the horizontal rail.
3. A unit according to claim 2 in which the U-shaped members are formed from spring steel one end of which is carried by the rear edge of the platform.
4. A unit according to any one of claims I to 3 in which the legs and rear frame are interconnected by one or more folding rails which extend there between and form part of the fall prevention barrier, said one or more folding rails having first and second parts and a folding joint intermediate said parts which can be locked against folding when the unit is in use by a spring-loaded plunger carried by one part which engages a locking formation carried by the other part.
5. A unit according to claim 4 in which the spring-loaded plunger engages a hole in the otherpart.
6. A unit according to claim 4 or 5 in which the spring-loaded plunger is J-shaped with the shorter end of the J-shaped plunger engaging the formation and the other end of the J-shaped plunger carrying a handle which is depressed against a spring surrounding the plunger and which acts between the handle said one part.
7. A unit according to any one of claims 1 to 6 in which the barrier includes an upper rail at the upper ends of the rear frame and legs and an intermediate rail located intermediate the upper rail and the platform, the portions of the upper rail and intermediate rail extending between the legs and the rear frame having folding joints intermediate their ends to allow the unit to fold and the platform being connected with legs via a first pair of links each pivoted at one end on a respective leg and at the other end on an intermediate portion of the platform to allow the unit to fold to the substantially parallel folded configuration.
8. A unit according to claim 7 in which the positioning of the joints in the upper and intermediate rails and the location of the connection between the links and the intermediate portion of the platform allow the upper rail to fold downwardly and the intermediate rail and links to fold upwardly as the unit is folded.
9. A unit according to claim 8 in which connecting links extends between the axes of the folding joints of the intermediate rails and the axes of the connections of the first links with the platform.
10. A unit according to any one of claims 1 to 9 provided with a fastening device which engages an adjacent vertical component of the structure to prevent tipping of the unit about the horizontal rail engaged by the pair of hooks.
11. A unit according to claim 10 in which the fastening device comprises two circumferential extending formations which extend partially around the vertical component in opposite directions and are axially spaced relative to the vertical component to define therebetween a gap inclined at an angle relative to the axis of the vertical component through which the vertical component can pass in a direction perpendicular to the axis of the vertical component when the fastening device is twisted to said angle to align the gap and the vertical component.
12. A unit according to any one of claims I to 11 in which the pair of legs contact the ground or a working deck of the structure to support the front edge of the platform from the ground or working deck.
13. A unit according to any one of claims I to 11 in which the pair of legs do not contact the ground or a working deck of the structure.
14. A safety unit for use with a scaffolding structure or other structure, the unit comprising a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of hooks carried by the rear frame to hook over a generally horizontal rail of the structure to secure the unit to and support the unit from the structure when in use, a pair of legs extending downwardly below a front edge of the platform when the platform is in use at an elevated generally horizontal position above the ground or a working deck of the structure, the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate between the upper portions of the legs above the platform for access to the platform, the rear frame, platform, legs and barrier being foldable into a generally parallel folded configuration when the unit is not in use for easy movement of the unit, the upper part of the legs and rear frame being interconnected by one or more folding rails which extend therebetween and form part of the fall barrier, said one or more folding rails having first and second parts and a folding joint intermediate said parts which can be locked against folding when the unit is in use by a spring-loaded plunger carried by one part which engages a locking formation carried by the other part.
15. A safety unit for use with a scaffolding structure or other structure, the unit comprising a worker's platform, a rear frame on which a rear edge of the platform is pivotally mounted, a pair of hooks carried by the rear frame to hook over a generally horizontal rail of the structure to secure the unit to and support the unit from the structure when in use, a pair of legs which extend downwardly below a front edge of the platform when the platform is in use at an elevated generally horizontal position above the ground or a working deck of the structure, the legs also extending upwardly above the platform when the unit is in use to form part of a fall prevention barrier which includes the rear frame and which completely surrounds the platform when the unit is in use, the barrier including an openable gate between the upper portions of the legs above the platform for access to the platform, the rear frame, platform, legs and barrier being foldable into a generally parallel folded configuration when the unit is not in use for easy movement of the unit, the barrier including an upper rail at the upper ends of the rear frame and legs and an intermediate rail located intermediate the upper rail and the platform, the portions of the upper rail and intermediate rail extending between the legs and the rear frame having folding joints intermediate their ends to allow the unit to fold and the platform being connected with the legs via a pair of links each pivoted at one end on a respective leg and at the other end on an intermediate portion of the platform to allow the unit to fold to the generally parallel folded configuration.
16. A safety unit for use within a scaffolding structure or other structure comprising an elevated workers platform supported above a normal platform or floor level of the structure by a support frame which hooks over a horizontal rail of the structure, a fall prevention barrier which surrounds the elevated workers platform, and a fastening device which engages an adjacent vertical component of the structure to prevent tipping of the unit about the horizontal rail of the structure, the fastening device comprising two circumferential extending formations which extend partially around the vertical component in opposite directions and are axially spaced relative to the vertical component to define therebetween a gap inclined at an angle relative to the axis of the vertical component through which the vertical component can pass in a direction perpendicular to the axis of the vertical component when the fastening device is twisted to said angle to align the gap and the vertical component.
17. A fastening device for securing a component to a tubular member, the fastening device comprising two circumferential extending formations which extend partially around the tubular member in opposite directions and are axially spaced relative to the tubular member to define therebetween a gap inclined at an angle relative to the axis of the tubular member through which the tubular member can pass in a direction perpendicular to the axis of the tubular member when the fastening device is twisted to said angle to align the gap and the tubular member.