WO2005093168A1

WO2005093168A1 - Fall-prevention device intended to prevent the unhindered fall of people into a corrugated well shaft.

Info

Publication number: WO2005093168A1
Application number: PCT/DK2005/000209
Authority: WO
Inventors: Jens Skov
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-03-26
Filing date: 2005-03-26
Publication date: 2005-10-06
Anticipated expiration: 2006-09-27
Also published as: DK200400486A

Abstract

The invention concerns a type of barrier secured horizontally to the inside of a corrugated well pipe and mainly at the top. The safety device is a circular construction that makes use of the internal profile in a corrugated well pipe and is assembled and curved within a given radius. The safety device consists of four movable arms at symmetrical angles mounted on and in extension of 2 perpendiculars to each other and crossed bars - substructure and superstructure. The substructure is installed first followed by the superstructure. Each arm has a rounded flange mounted on its end and on the same level. The curved and rounded flanges fit naturally into the corrugated design of the well shaft, so that the flanges on the four arms can rest on the edge of the corrugated well pipe. The safety device is then supplemented by installations such as warning flags/signs and floats.

Description

Fall-prevention device intended to prevent the unhindered fall of people into a corrugated well shaft.

The invention concerns a safety device in a well shaft. The safety device is intended to prevent accidental falls from becoming serious. The invention concerns a type of barrier secured horizontally to the inside of a corrugated pipe and mainly at the top. It will quickly arrest the fall of people, animals or objects and prevent them from falling to the bottom of the well. The device is simple to install and just as easy to remove. Current fall-prevention devices for open well shafts are often more or less interim barriers around the shaft. Barriers can often be poorly guarded, which means that there is a risk that children and animals could fall into open shafts. The invention is a circular construction that fits inside the well shaft. It is very simple to install and just as easy to remove - and does not necessarily require the use of tools. It features a specially-designed circular construction of mainly stainless steel that makes use of the internal profile of a corrugated pipe. The fall-prevention device consists of profiles of a rigid material assembled and curved in a given radius. In greater detail the fall-prevention device consists of four arms at symmetrical angles mounted on and in extension of 2 perpendicular to each other and crossed bars - substructure and superstructure. The cross piece assembly consists of aligned recesses opposite each other in the centre of the sub- and superstructure, such that when assembled, the upper sides of both are level with each other.

Each arm has a rounded flange mounted on its end and on the same level. Together the four extended arms with the rounded flange form an apparent circular unit. On the examples shown in the drawings each of the rounded flanges occupies approx. 1/8 of a circle's circumference.

Other dimensions will be covered by the device using the same principle. The curve fits naturally into the corrugated design of the well, so that the flanges on the four arms can rest on the edges of the corrugated pipe.

Seen from the inside the interior of a corrugated pipe wi ll appear as if it is composed of a repeated series of horizontal pipe-shaped coils and in between each of these will appear to be a series of hollows.

It is these hollows and the projections of the same that are used as the resting point for the extremities of the fall -prevention device - the rounded flange. The flanges themselves are principally made of plastic, so that the fall-prevention device rests on a protective material.

The arms are movable such that they can be retracted towards the centre of the fall-prevention device and extended outwards again.

This has the particular advantage that when the arms are retracted the fall-prevention device appears very compact making it easy to position the fall-prevention device anywhere desired in the well shaft. The arms are also self-locking using a technical contrivance when in their extended position, whereby the fall-prevention device is locked in place in the well shaft. The drawings show an example of how the arms can be technically moved.

Previous description is given of how the four arms of the fall -prevention device consist of 2 perpendicular to each other and crossed bars. This assembly entails a simplification of actual installation, in that one of the 2 bars (substructure) is installed first, followed by placing the second bar (superstructure) securely onto the cross piece. This procedure makes handling more controlled and manageable. Each of the arms in the example is fastened on the outside of a short flat horizontal bar extending from the centre and that has two side surfaces created by the edges being bent into a vertical plane. Two elongated slots one after the other and with a small gap between them have been drilled on both sides of the two side surfaces and opposite each other. In principle the arms have almost identical physical dimensions with the bars extending from the middle of the fall-prevention device mentioned above - the difference is that the arms are longer and a little wider. Due to the slight extra width the arms can be positioned on the outside of the bars extending from the centre of the cross piece, and be secured to the same through the aforementioned slots using screws and nuts. Finally, a support arm is screwed on to the narrow end of each of the four flanges. These support arms are bent and angled such that at the opposite end they are secured using the same screws as the arms are secured with. Importantly the arms and flanges can now be secured in the desired position by the aforementioned screws being inserted through the elongated drilled holes - through both arms and the bars extending from the centre and the support arms. It is however important to note that movement can be restricted if the aforementioned screws are screwed too tightly. Inside the arm and at the top of the same is a suitably long lock plate of mainly hardened steel and that is secured at one end (furthest from the centre) mainly by two rivets. A significant part of the lock plate therefore has no fastening allowing it to be manipulated and can thus be lifted over a relatively short stud. When the lock plate is resting on the stud the arms can be moved backwards and forwards.

When the lock plate is behind the stud the arms are locked in their extended position and this is a position suitable for securing inside the well shaft.

The lock position is thus adapted to ensure the arms in this position will be optimally pressed into the selected hollow on the inside of the well shaft. The lock plate is pushed from its lock position over the stud and a sharp object used to press through a hole in the arm positioned over the outside of the lock plate. A small tool could be hung on a short length of chain for this purpose in the vicinity of the hole. The arm and thus the lock plate can now be pushed inwards towards the centre, reducing the diameter of the fall-prevention device. A movement towards the centre forces the arm closer to the bar radiating from the centre - the structure.

It can be practical to lock the fall-prevention device in its extended position, so that any attempts at vandalism, tomfoolery or theft will be discouraged.

A locking device is arranged in the cross piece that prevents the arms from being pushed inwards when the fall-prevention device is in its extended position and locked, by placing blocking devices in the end of the sub- and superstructures that face towards the centre.

The blocking devices consist of 4 rigid and robust pins that can be pushed up through 4 purpose-drilled holes in the arms of the sub- and superstructure positioned on the edge of the extended and movable arm parts. The 4 pins are all anchored on a form of body that is solid and mainly made of steel. In the middle of this is a shaft that is pressed upwards at the same time as the pins, but unlike the pins extends over the edge of the centre of the cross piece through a hole in the same. At this position there is a hole drilled through the shaft immediately over the upper edge of the substructure for the purpose of passing a padlock through to lock the substructure in its extended position and there is a corresponding hole drilled through the part of the shaft that projects above the superstructure to lock the position of the superstructure, but also the entire fall-prevention device. The part of the shaft that projects above the superstructure can be used for other measures. A warning sign can be fitted to it at the end of the shaft, such that the upper part of the sign will project sufficiently above the well surface level, such that the sign or a flag will be visible in a wide area around the well.

This kills two birds with one stone - a fall-prevention advice and a visible warning arrangement. Finally it will also be possible to fit a float with cord attached to the projecting part of the shaft. The function of this will be justified in the event of water rising above the level of the fall-prevention device, such that it is no longer visible. The float will attract attention to the fact that there is a fall-prevention device and the cord will indicate distance from the water surface to the fall- prevention device.

If the water level is below the fall-prevention level the float will rest in the special holder provided for the purpose.

Finally, the float can be fitted along with and concurrent with the warning sign and in the event of the water level being below the level of the fall-prevention device, the float will be able to rest in its own container,, placed in the vicinity of the centre.

Locking of float and warning sign is performed by placing the same padlock previously mentioned thro ugh the holes in the pipes the float and sign respectively have that extend over the shaft and that are positioned to align with the original holes in the shaft intended for locking.

Some typical well shafts the fall-prevention device can be used in are inspection shafts, access shafts, culverts, road manholes and sluice wells. The fall-prevention device can be adapted to a suitable size depending on the diameter of the corrugated pipe in which the fall-prevention device is to be placed. GB 2283049 is a fall-prevention device with the same technical features as the present invention, but Is a 3 armed circular fall-prevention device with expanding ring or arms. However GB 2283049 is a fall-prevention device intended

. for concrete pipes with smooth or flat internal sϊ des. Furthermore this fall-prevention device is intended to be mounted more or less permanently in a concrete pipe. The fall-prevention device is significantly more complicated to install and remove. It will be unusable in a plastic corrugated pipe, as the risk of physical damage to the plastic will be very high. A corrugated pipe differs from a flat and hard inner wall of a concrete pipe in that the design of its inner surface offers a series of shelves, on which the outer parts of the fall- prevention device are designed to rest upon. This aspect has the advantage that the fall-prevention device can be lifted a little and rotated in the desired direction - e.g. when pressure-washing the lowest part of the well. The hose may have to be passed down into the adjoining subterranean pipe and if the fall-prevention device can be easily moved, it will give optimum conditions for manipulating and positioning the hose. One of the two bars the fall-prevention device consists of - the superstructure - can also be removed from the well, providing ample space for pressure washing if required. The substructure could be suitably locked in its extended position in the way described above, by passing the padlock through the purpose-drilled lowest hole* in the shaft. For final securing in place the 2 bars are put together again, whereupon the arms can be extended into the locked position. The techniques used to extend the arms are significantly different from GB 2283049. In the present invention the arms are simply extended into a locking position whilst in GB 2283049 the two arms have to be screwed to the concrete pipe inner wall to secure them. This is difficult to manage especially down in a concrete pipe. Figures 15 to 18 in WO 95/21304 describe a fall- prevention device configured for corrugated pipes. A circular (iron?) construction that fits into the inside of the well shaft is secured at a suitable point mainly at the top of the shaft, and functions as a fall-prevention device. The construction consists of two halves that are fastened together in the middle when placed in the shaft. Locking the two halves together is achieved using a specially designed U-shaped object that joins the two halves together with the help of a hammer. This construction is significantly more usable than that initially described, but installation requires tools and installation is intended to be permanent. This can make the idea of the invention inappropriate if removal of the fall -prevention device is intended. This process may prove to be very inconvenient and there is a risk of damaging the actual fall-prevention device during the same process. The present invention will be able to resist the impact of the fall of a grown adult. Key to figures

Figure 1 Fall-prevention device seen from above

Figure 2 Fall-prevention device - bottom in detail

Figure 3 Substructure with lock device. The unlocked and arm parts positioned retraceted towards the centre of the fall-prevention device

Figure 4 Substructure with lock device. Locked and arm parts extended out to extended position

Figure 5 Corrugated well shaft with fall-prevention device

Numbering

1. substructure and 2. superstructure 3. cross piece - centre 4. movable arm parts 5. flanges 6. support arms 7. slots 8. screws/shafts in slots 9. lock plate

10. rivets for lock plate

11. stud 12. hole for lock release

13. corrugated well shaft with fall-prevention device 4. pipe-shaped coils, seen from inside a corrugated pipe

15. hollows - seen from the inside of a corrugated pipe

16. fall-prevention device in corrugated pipe

17. padlock 18. stop screw for lock shaft

19. shaft for padlock

20. plate for stop screw

21. pins

22. body for pins 23. lock ring

24. recess for padlock

25. split pin for shaft

26. container for float

27. cord for float 28. float

29. shaft for sign/flag

30. flag pole

31. sign/flag

32. screw for flag/sign

Figure 1 shows the fall-prevention device in perspective and from above. The materials can mainly be stainless steel, whilst the flanges (5) will usually be made of plastic. The figure clearly illustrates the principals of the fall- prevention device's functionality. The movable arm parts (4) are shown in extended position in the figure. In greater detail the fall-prevention device consists of four arms at symmetrical angles mounted on and in extension of 2 perpendicular to each other and crossed bars - substructure (1) upon which the superstructure (2) is placed. The cross piece assembly consists of aligned slots opposite each other in the centre of the sub- and superstructure, such that when assembled, the upper sides of both are level with each other.

In terms of their construction and technically the flanges (5) are screwed to the other parts of the frame of the fall- preventive device using the support arms (6). These increase stability significantly. Please refer to more details given later in this section.

Figures 2, 3 and 4 provide a technical illustration of how the arms can be moved in and out. The screws (8) pass through the elongated drilled slots (7) the length of which is a vital indicator for the movement tolerance of the arms (3).

It is however important to note that movement can be restricted if the aforementioned screws (8) are screwed too tightly. Inside the arms (3) and at the top of the same is a suitably long lock plate (9) and that is secured at one end

(furthest from the centre) mainly by two rivets (10). A significant part of the plate therefore has no fastening allowing it to be manipulated and can thus be lifted over a relatively short stud (11). When the plate is resting on the stud (11) the arms (3) can be moved backwards and forwards.

When the lock plate (9) is behind the stud (11) the arm (3) is locked in its outer position and thus in a position suitable for securing inside the well shaft. The lock position is thus adapted to ensure the arms (3) in this position will be optimally pressed into the selected hollow on the inside of the well shaft.

The lock plate (9) is pushed from its lock position over the stud (11) by pressing a sharp object through a hole in the arm positioned over the outside of the lock plate (9).

A small tool could be hung on a short length of chain for this purpose in the vicinity of the hole (12).

The arm (3) and thus the lock plate (9) can now be pushed inwards towards the centre, reducing the diameter of the fall-prevention device. Moving the arms

(3) towards the centre forces them over either the substructure (1) or superstructure (2).

This can be seen by the position of the lock plate (9) in fig. 3 pressed up over the stud (11) and in fig. 4 behind the stud (11).

The same in fig. 3 and 4 illustrates a blocking device in the cross piece and that consists of 4 rigid and robust pins

(21) that can be inserted into the 4 purpose-drilled holes in the arms of the sub- and super structure positioned on the edge of the extended and movable arm parts. The 4 pins (21) are all anchored on a form of body (22) that is solid and mainly made of steel.

In the middle of this is a shaft (19) that is pressed upwards at the same time as the pins (21), but unlike the pins (21) extends over the edge of the centre of the cross piece through a hole in the same. At this position there is a hole drilled through the shaft (19) immediately over the upper edge of the substructure for the purpose of passing a padlock through to lock the substructure (1) in its extended position and there is a corresponding hole drilled through the part of the shaft that projects above the superstructure to lock the position of the superstructure (2), but also the entire fall-prevention device. Figure 5 illustrates that a warning sign/flag (31) can be fitted to the end of the shaft (19), such that the upper part of the sign/flag (31) will project sufficiently above the well surface level, such that the sign/flag (31) will be visible in a wide area around the well. A float can also be attached to the end of the upper part of the shaft (19). The float (28) is fitted with a suitably long cord (27) and which is fastened to a pipe, and that is compatible with the diameter of the shaft, such that the pipe can be used as an anchoring element down in the shaft pipe. If the water surface is below the level of the fall-prevention device the float will rest in its own container (26), mounted on the end of the shaft (19). Finally, the float (28) can be fitted along with and concurrent with the warning sign/flag (31) and in the event of the water level being below the level of the fall- prevention device, the float will be able to rest in its own container, placed in the vicinity of the centre. Locking of float (28) and warning sign/flag (31) is performed by placing the same padlock as mentioned in claim 3 through the holes in the pipes of the float (28) and sign/flag (31) respectively that extend over the shaft (19) and that are positioned to align with the original holes in the shaft (19) intended for locking. Figure 5 shows a cross-section of a corrugated well shaft (13) with fall-prevention device (16). Seen from inside the interior of a corrugated pipe will appear as if it is composed of a repeated series of horizontal pipe-shaped coils (14) and in between each of these will appear to be a series of hollows (15). It is these hollows (15) and the projections of the same that are used as the resting point for the extremities of the fall-prevention device (16) - the rounded flange (5).

Claims

Claim 1 :

Fall-prevention device intended to prevent the unhindered fall of people and large objects into a corrugated well shaft C h a r a c t e r i s e d by a circular construction of mainly stainless steel that makes use of the internal profile in a corrugated pipe (13) and is assembled and curved within a given radius The fall-prevention device consists of four movable arms (3) at symmetrical angles mounted on and in extension of

2 perpendicular to each other and crossed bars - substructure (1) upon which the superstructure (2) is placed. The cross piece assembly consists of aligned recesses in the centre of the sub- and superstructure, such that when assembled, the upper sides of both are level with each other and each arm (3) has a rounded flange (5) mounted on its end and on the same level. Together the four arms (3) with the rounded flanges (5) form an apparent circular unit. On the examples shown in the drawings each of the rounded flanges occupies approx. 1/8 of a circle's circumference. Other dimensions will be covered by the device using the same principle. The curved and rounded flanges (5) fijt naturally into the corrugated design of the well shaft, so that the flanges (5) on the four arms can rest on the edge of the corrugated pipe. In more detail it is these hollows (15) and the projections of the inside of the well shaft that are used as the resting point for the extremities of the fall- prevention device - the rounded flange (5). The flanges themselves (5) are attached to a frame on the arms (3) and are mainly made of plastic. Claim 2:

Fall-prevention device in pursuance of claim 1 C h a r a c t e r i s e d by the arms (3) are movable such that they can be pushed out from the centre of the fall-prevention device to a locked extended position and back in from there. Each of the arms (3) is affixed to the structural parts in the cross piece - i.e. substructure (1) and superstructure (2), and on each of these the longitudinal sides are bent to form side surfaces. Two elongated slots (7) one after the other and with a small gap between them have been drilled on both sides and opposite each other of the two side surfaces. The arms (3) are longer and a little wider but also with side surfaces, adapted to dimensions that can be assembled with and extend the respective structures (1 and 2). The arms (3) are secured to the structures by similar slots to those mentioned above and that are adapted to these in design (7). All slots are aligned opposite each other whereby screws with nuts (8) can be inserted. The support arms (6) are bent and angled such that at the opposite end they are secured using the same screws and bolts (8) as mentioned above. The length of the slots (7) will determine tolerance but are adjusted to the diameter of the shaft in which the fall-prevention device is installed. Inside the arms (3) and at the top of the same is a suitably long lock plate (9) mainly of iron and that is secured at one (furthest from the centre) mainly by two rivets (10). A significant part of the plate therefore has no fastening allowing it to be manipulated and can thus be lifted over a relatively short stud (11). When the plate is resting on the stud (11) the arms (3) can be moved backwards and forwards. When the lock plate (9) is behind the stud (11) the arm (3) is locked in its outer position and thus in a position suitable for securing inside the well shaft. The lock position is thus adapted to ensure the arms (3) in this position will be optimally pressed into the selected hollow on the inside of the well shaft. The lock plate (9) is pushed from its lock position over the stud (11) by pressing a sharp object through a hole in the arm positioned over the outside of the lock plate (9). A small tool could be hung on a short length of chain for this purpose in the vicinity of the hole (12).

Claim 3:

Fall-prevention device in pursuance of one or more of the claims above

C h a r a c t e r i s e d by a blocking device in the cross piece and that consists of 4 rigid and robust pins (21) that can be inserted into the 4 purpose-drilled holes in the arms of the sub- and superstructure positioned on the edge of the extended and movable arm parts. The 4 pins (21) are all anchored on a form of body (22) that is solid and mainly made of steel. In the middle of this is a shaft (19) that is pressed upwards at the same time as the pins (21), but unlike the pins (21) extends over the edge of the centre of the cross piece through a hole in the same. At this position there is a hole drilled through the shaft (19) immediately over the upper edge of the substructure for the purpose of passing a padlock through to lock the substructure (1) in its extended position and there is a corresponding hole drilled through the part of the shaft that projects above the superstructure to lock the position of the superstructure (2), but also the entire fall-prevention device.

Claim 4:

Fall-prevention device in pursuance of claim 3

C h a r a c t e r i s e d by the mounting of a warning sign/flag (31) that can be fitted to the end of the shaft (19), such that the upper part of the sign/flag (31) will project sufficiently above the well surface level, such that the sign/flag (31) will be visible in a wide area around the well.

Claim 5:

Fall-prevention device in pursuance of claim 3 and/or 4

C h a r a c t e r i s e d by the attachment of a float to the end of the upper part of the shaft (19). The float (28) is fitted with a suitably long cord (27) and which is fastened to a pipe, and that is compatible with the diameter of the shaft, such that the pipe can be used as an anchoring element down in the shaft pipe. If the water surface is below the level of the fall-prevention device the float will rest in its own container (26), mounted on the end of the shaft (19). Finally, the float (28) can be fitted along with and concurrent with the warning sign/flag (31) and in the event of the water level being below the level of the fall- prevention device, the float will be able to rest in its own container, placed in the vicinity of the centre. Claim 6:

Fall-prevention device in pursuance of claim 3 and/or 4

Characterised by locking of the float (28) and warning sign/flag (31) is performed by passing the same padlock mentioned in claim 3 through the holes in the pi pes the float (28) and sign/flag (31) respectively have that extend over the shaft (19), and that are positioned to align with the original holes in the shaft (19) intended for locking.