EP2832937B1

EP2832937B1 - Anti-fall safety equipment, in particular for realizing floors in residential housing

Info

Publication number: EP2832937B1
Application number: EP14178659.0A
Authority: EP
Inventors: Paolo Vaccarini
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-08-02
Filing date: 2014-07-25
Publication date: 2016-03-16
Anticipated expiration: 2034-07-25
Also published as: ITAN20130145A1; EP2832937A1

Description

The present invention for industrial patent relates to an anti-fall safety equipment, in particular for realizing floors in residential housing.
More precisely, the present invention relates to a preventive and protective equipment against falls from a height, which allows for realizing horizontal structures, such as beams and floors for residential housing, having a minimum distance between the work surface and the underneath level lower than 3 m and higher than the maximum height of 2 m required by the safety regulations of building yards.
According to the safety standards of building yards, all workers working at a height higher than 2 m must be equipped with a safety system to prevent the impact with the ground in case of fall.
More precisely, in the case of a worker falling off a scaffolding or a floor, the safety system must stop the free fall and hold the worker in such manner to avoid personal injuries.
According to one of these anti-fall safety systems:

a network of horizontal ropes is realized above the beams;
a sling is worn by the worker;
the end of a safety cable is attached to the sling and the other end of the safety cable is slidingly attached to one of the horizontal ropes of the network.

In order to obtain such a network of ropes, a set of uprights is fixed on top of the pillars, being provided with an upper eyelet into which at least one horizontal rope is inserted.
After wearing the sling, the operator can attach one end of the safety cable to the sling and the other end of the safety cable to a rope of the network of horizontal ropes, for example with a snap-hook.
In view of the above, the worker is attached to the network of horizontal ropes with the safety cable. At the same time he can move between the pillars because the upper end of the safety cable can slide with respect to the horizontal rope where it is attached.
The drawback of such a system consists in the limited length of the safety cable.
Obviously, the length of the safety cable determines the free movement and the maximum travel of the worker in case of a free fall.
In fact, a very long safety cable would provide a wide freedom of movement to the workers, but would not guarantee a safety stop in case of an accidental free fall.
Therefore the design of the safety system must take into account these two conflicting requirements. ITAN20110174 A1 discloses a safety equipment according to the preamble of claim 1.
For a better understanding of the invention, the description of the prior art continues with reference to Figs. 1 and 2, which diagrammatically show what happens in case of an accidental fall of a worker.
As mentioned above, the parameter that must be guaranteed according to the legislation is the safety height (QS), which is the height at which the free fall of the worker is stopped, with respect to the underneath surface, in case of a free fall.
Fig. 1 shows a lower level (PI) and an upper level (PS) supported by three aligned pillars (1) extending between said lower level (PI) and said upper level (PS). Fig. 1 also shows three uprights (2), each of them being fixed on top of each pillar (1) and being provided with a top eyelet (12) wherein a horizontal rope (3) is inserted.
On said horizontal rope (3) the upper end (4a) of a safety cable (4) is slidingly fixed, the lower end of which (4b) is fixed to a sling (5) worn by the operator (6) standing on the upper level (PS).
In order to facilitate the insertion of all the horizontal ropes (3) into the eyelets (12), as well as the fixing/unfixing of the upper end (4a) of the safety cable (4) to each of said horizontal ropes (3), the height (h2) of the uprights (2) must exceed the height of the operator (6) slightly; more precisely, said height must be such to allow the operator (6) to carry out these operations while standing on the upper level (PS) without using a ladder or the like.
Fig. 2 shows what happens when the operator (6) accidentally falls from the upper level (PS).
The body of the operator (6) stops at a safety height (QS) that depends on the height (h1) of the pillars (1), on the height (h2) of the uprights (2), on the length (h4) of the safety cable (4), on the arrow (F) caused by the downward bending of the horizontal rope (3) where the safety cable (4) is fixed, and on the height (h5) of the operator (6).
The height (h5) is the distance between the fixing point of the safety cable (4) to the sling (5) and the feet of the operator (6).
Using the same rope (3), the arrow (F) depends on the length of the horizontal rope (3) given that the latter is only fixed at its ends.
In other words, the longer is the horizontal rope (3) the higher is the arrow (F).
More precisely: $QS = h 1 + h 2 - h 4 - F - h 5$
Such an anti-fall safety equipment is not suitable to work in structures with a height (h1) of the pillars (1) between two levels (PI and PS) lower than 3 m.
In such a case, the design of the safety equipment should alternatively provide for:

a very short safety cable (4), which considerably limits the movements of the operator (6);
a height (h2) of the uprights (2) much higher than the height of the operator (6), which makes it extremely difficult for the operator to insert the horizontal ropes (3) inside the eyelets (12), as well as to fix/unfix the upper end (4a) of the safety cable (4) to each of the horizontal ropes (3).

Both the aforementioned solutions make the anti-fall safety system inappropriate in similar conditions.
The purpose of the present invention is to devise a new anti-fall safety equipment that, while maintaining the aforementioned structural configuration, can be advantageously used also when floors are spaced by a distance lower than 3 m. Such purpose is achieved with a safety equipment according to claim 1.
The present invention is based on the provision of one or more tightening and tensioning devices on top of each upright (2), which are adapted to fix and advantageously tighten a section of the horizontal rope.
More precisely, according to a first embodiment of the invention, each of said devices allows for inserting the horizontal rope through an eyelet and tightening it.
Considering that the longer is the horizontal rope (3), the higher is the arrow (F) and given that each rope (3) is tightened to each upright (2), the rope (3) can be divided into several sections (3a) comprised between an adjacent pair of uprights (2).
In view of the above, only a section (3a) of the rope (3), and precisely the section where the safety cable (4) is fixed, is stressed in case of fall of the operator (6).
According to another embodiment of the present invention, said tightening devices also allow for tensioning the rope (3).
By tensioning each section (3a) of rope (3), the length of the arrow (F) can be considerably reduced, thus partially reducing the natural elasticity of the rope (3).
For explanatory reasons, the description of the equipment according to present invention continues with reference to the attached drawings, which only have illustrative, not limiting value, wherein:

Fig. 3 is an axonometric view of a pillar on top of which a bush for the upright (2) is fixed;
Fig. 4 is an axonometric view of a,set of pillars, like the ones of Fig. 3, connected by means of a network of horizontal ropes inserted into the eyelets obtained on top of the uprights (2);
Figs. 5 and 6 are two axonometric views that show the insertion of one of the uprights (2) into a bush (8) adapted to be drowned into the pillar (1);
Figs. 7 and 8 are two axonometric views that show one of the uprights (2) respectively uncoupled and coupled with a tightening and tensioning device (7) of the invention; Fig. 8 shows the cooperation of the striker (9) with the teeth (7c) of the tightening and tensioning device (7);
Fig. 9 is an axonometric view that shows, in uncoupled position, one of the uprights (2) with two identical tightening and tensioning devices (7) positioned one on top of the other; Fig. 9 shows the cooperation of the striker (9) with the teeth (7c) of the tightening and tensioning device (7);
Figs. 10A and 10B are views of the tightening and tensioning device (7) with the striker (9);
Fig. 11 is an axonometric view that shows two uprights (2), according to a preferred embodiment of the invention, of which one is in assembled condition and the other one is in exploded condition;
Figs. 12 and 13 are views of a tightening and tensioning device (7) provided with an innovative bush (T), in uncoupled and coupled condition, respectively;
Figs. 14 and 15 are axonometric views of the bush of Figs. 12 and 13, respectively a top view and a bottom view;
Fig. 16 is a view of the bush (8) provided with a plug (81) and partially drowned inside the pillar (1); said bush (8) being cut along a vertical plane passing through the axis of the bush (8);
Fig. 17 is a view of the bush (8) of Fig. 16, with the plug (81) extracted from the bush (8).

With reference to the attached figures, the equipment of the invention comprises a set of uprights (2) with lower end section (2b) fixed on top (1 a) of a pillar (1) and with upper end section (2a) provided with tightening and tensioning means (7) of at least one horizontal rope (3) that connects two adjacent uprights (2).
According to the embodiment of the invention shown in Figs. 3, 4, 5 and 6, the equipment comprises a set of bushes (8) adapted to be fixed on top of the pillar (1), substantially in axis, in such manner that one of the two ends of the bush (8), specifically the upper end (8a), is faced upwards.
As shown in Fig. 3, the bush (8) can be partially drowned inside the pillar (1) as long as the mouth (8b) defined by the upper end (8a) can be accessed from above.
After positioning all the bushes (8), it is necessary to insert the lower ends (2b) of each upright (2) into the bush (8).
Figs. 7 and 8 show one of the tightening and tensioning devices (7) of the horizontal ropes (3), as well as the tensioning means (7c,9) that cooperate when said tightening and tensioning device (7) is coupled with the upright (2).
More precisely, although it has a quadrangular section, each upright (2) has an upper end (2a) with an upper circular mouth (2c) adapted to house the lower end section (7a) of the tightening device (7).
According to a preferred embodiment of the invention, which is also shown in Fig. 9, said tightening and tensioning device (7) consists in a circular sleeve (7) provided with a lower end (7a) having the external diameter identical to the internal diameter of the upper end (2a) of the upright (2).
Moreover, the device (7) is provided with an upper end (7b) having the internal diameter identical to the internal diameter of the upper end (2a) of the upright (2).
As shown in Fig. 9, in view of the above, each device (7) can be fixed with each upright (2), and it can also be fixed in such manner that multiple tightening and tensioning devices (7) are overlapped in the same upright (2), thus allowing the user to personalize the network of horizontal ropes (3).
The upper end section (2a) of the upright (2) and the lower end section (7a) of the sleeve (7) are provided with means (7c, 9) adapted to lock the rotation of the sleeve (7) with respect to the upright (2).
Said means (7c, 9) consist in a toothed profile (7c) obtained on the external surface of the lower end section (7a) of the sleeve (7), and in a striker (9) arranged in correspondence of the upper end section (2a) of the upright (2) and provided with a tip adapted to be engaged inside a tooth of said toothed profile (7c) as soon as the sleeve (7) is completely inserted into the upright (2).
The sleeve (7) is provided with an external annular tooth (7d) that acts as stop and defines the lower end section (7a) with smaller external diameter with respect to the upper end section (7b) with larger diameter.
The sleeve (7) is also provided with a pair of diametrally opposite longitudinal notches (7e) ending in upper position; said longitudinal notches (7e) are adapted to house one of the horizontal ropes (3) that are inserted inside the notches (7e) from above.
After inserting the horizontal ropes (3) into a pair of notches (7e), the tightening and tensioning of the horizontal ropes (3) provides for rotating the sleeve (7) with respect to the upright (2) wherein it is inserted, or with respect to the sleeve (7) underneath, in case of multiple sleeves (7) disposed one on top of the other and supported by the same upright (2), as shown in Fig. 9.
During rotation the striker (9) is retracted and overrides the teeth until rotation is completed; in such a configuration, the striker (9) is inserted and pushed inside the tooth opposed to it.
It must be noted that such a striker (9) is not provided with a spring and is pushed by its weight in normal operating position.
After positioning and tensioning all the horizontal ropes (3), a network of horizontal ropes (3) is realized, and each rope (3) is provided with a set of sections (3a) comprised between two adjacent uprights (2).
The equipment of the invention also comprises a sling (5) adapted to be worn by the operator (6) and a safety cable (4) with lower end (4b) fixed to said sling (5), whereas the upper end (4a) is slidingly and selectively fixed to one of the sections (3a) of the horizontal ropes (3) of the network.
Figs. 10A and 10B show the tightening and tensioning device (7) with the striker (9); specifically the striker (9) has a T-shaped enlarged head adapted to be actuated by an ordinary hammer.
More precisely, the striker (9) ends with a transversal wing (91) that can be grabbed with the forked end of a hammer, such as the ones that are normally used to remove nails.
A hammer can be used to unlock the striker (9), exactly like when removing a nail.
So the striker (9) can be actuated easily, considering that, in operational position, it requires a great amount of energy in order to be disengaged from the tooth of the toothed profile (7c).
Alternatively, the striker (9) can be hit from down up in order to be disengaged from the toothed profile (7c).
The striker and its housing are shaped in such manner that, when the striker is engaged with the toothed profile (7c), the device (7) can be extracted backwards only if the striker (9) is lifted.
Fig. 11 shows the upright (2) according to a second embodiment, wherein a stiffening rod (20) is inserted into the upright (2).
The provision of the stiffening rod (20) increases the rigidity of the upright (2) in any radial direction of stress, unlike tie-rods that would make the upright (2) rigid almost exclusively in a direction opposite to the one in which they are fixed to the upright (2).
By inserting the stiffening rod (20) either internally or externally to the upright (2), the rigidity of the upright (2) depends on the thickness of the upright (2) and additionally on the thickness of the stiffening rod (20); alternatively, in order to obtain such a rigidity, the thickness of the upright (2) can be increased, although this results in a higher weight of the upright during the installation of the equipment (in contrast with the safety regulations for building yards).
Fig. 11 shows an upright (2) and a stiffening rod (20) with square section.
Referring to Figs. 12 to 15, the equipment of the invention comprises a bush (T) adapted to close the sleeve (7).
The peculiarity of the bush (T) consists in a top wall (T1), which is centrally provided with a hole (T2) with square section wherein the square pin of a dynamometric wrench (not shown in the attached figures) is inserted.
The top wall (T1) of the bush (T) is also provided with a side (T1 a) faced towards the sleeve (7), from which two teeth (T3) protrude in diametrally opposite position, which are adapted to be inserted in the pair of notches (7e); by rotating the bush (T) with a dynamometric wrench, rotation is transmitted to the sleeve (7) by means of the pair of teeth (T3) inserted into the pair of notches (7e) in order to precisely tension the rope (3) inserted in the pair of notches.
The provision of such a bush (T) makes it possible to use a dynamometric wrench to tension the ropes (3) of the equipment of the invention using the same force, with utmost precision, in order to guarantee the perfect operation of the equipment.
In order to stiffen the teeth (T3) the bush of the invention is provided with a side edge (T4) to which said teeth (T3) are joined; said edge (T4) surrounds and embraces the top section of the sleeve (7) when the bush (T) is inserted onto the sleeve (7) in operating position.
Moreover, it must be said that the side edge (T4) allows the bush to remain inserted on the tightening and tensioning device (7) without having to be constantly maintained in the correct operating position by the operator.
The side edge (T4) is provided with a notch (T5) perpendicular with respect to the top wall (T1), which houses the striker (9), as shown in Fig. 13.
Finally, it must be noted that the equipment of the invention preferably comprises a Y-shaped safety cable so that the operator can fix the lower end of the Y-shaped cable to the sling, and the other two upper ends of the Y-shaped cable to two adjacent sections (3a) of the rope (3) in order to guarantee the safety of the operator, who is always attached with at least one of the two end sections of the safety cable.
More precisely, when moving along a rope (3) and passing beyond an upright (2), the operator can unfix the first end section of the Y-shaped cable, fix it to a section of rope (3) downstream the upright (2) and remain attached to the section of rope (3) upstream the upright (2) with the second end section of the Y-shaped cable.
After fixing the first end section of the Y-shaped cable to the rope (3), the operator can unfix the second section of the Y-shaped cable and fix it along the rope (3) downstream the upright (2) to continue his route.
As shown in Figs. 16 and 17, the bush (8) has a quadrangular section and the equipment of the invention comprises a plug (81) with basically T-shaped configuration, which comprises a vertical portion (81 a) adapted to be exactly inserted into the bush (8) and an enlarged head (81 b) adapted to remain outside the bush (8) and rest on the mouth (8b) of the bush (8).
More precisely, the plug (81) comprises:

a quadrangular vertical portion (81 a) adapted to be completely and exactly inserted into the bush (8) passing through the mouth (8b) of the bush (8) and acting as lower plug for the bush (8);
an enlarged head (81 b) with a lower stop surface (81 c) engaged on the mouth (8b) of the bush (8);
two wings (81 d) protruding downwards from said enlarged head (81 b) and adapted to be arranged in side-by-side position close to the upper end of the bush (8) when the plug (81) is completely inserted inside the bush (8).

It must be noted that the height of the wings (81 d) is identical to the height of the upper end (8a) of the bush (8), which protrudes from the top (1 a) of the pillar (1) when the bush (8) is drowned inside the pillar (1).
The plug (81) is used to correctly operate the bush (8), which must be partially drowned inside the pillar (1).
More precisely, the plug (81) is inserted inside the bush (8) and, as soon as the pillar is cast, the bush and the plug are simultaneously inserted inside the pillar from above, until the wings (81 d) of the plug (81) are engaged on the free surface of the concrete casting.
When concrete solidifies, the plug (81) can be extracted from the bush (8), which remains firmly drowned inside the pillar (1), with the upper end (8a) protruding from the top (1 a) of the pillar (1).
Otherwise said, the use of the plug (81) gives the following advantages:

it prevents the liquid concrete from going back up inside the bush (8) and occupying the space where the lower end (2b) of the upright (2) is to be inserted;
the wings (81 d) protruding downwards from the enlarged head (81 b) are used as reference points for the insertion of the bush (8) inside the concrete casting when the concrete is still in liquid state. In fact, by simultaneously inserting the bush (8) and the plug (81) in the pillar (1), until the wings (81 d) of the plug (81) are engaged on the free surface of the concrete casting, it is guaranteed that the upper end (8a) of the bush (8) protrudes from the top (1a) of the pillar (1) for a height (h) identical to the height (h) of the two wings (81 d);
a level can be positioned onto the enlarged head (81 b) of the plug (81) in order to place the bush (8) in perfectly vertical position;
when the plug is extracted from the bush and additional concrete is cast to embed the bush, the concrete can penetrate inside the bush, fill it and join the concrete of the bottom wall that defines the cavity of the bush, thus restoring the continuity of the concrete.

In conclusion, the use of the equipment of the invention provides for the following operations:

inserting a bush on top of the pillars upon casting in order to obtain a structural anchoring point;
removing the plug from the bush;
inserting an iron pole with suitable dimensions in the bush, with or without internal or external reinforcement, adapted to guarantee resistance and provided on top with a locking system;
inserting a sleeve on top of the pole, said sleeve having in lower position a set of teeth in contrast with the locking system provided in the head of the pole and having in upper position a pair of notches to insert the rope (3); said sleeve being configured in such manner to be inserted into the head of each pole, as well as in a sleeve already positioned on the pole, in such manner to form a column;
inserting the rope (3) in the pair of notches;
rotating the sleeve manually so that the rope (3) makes at least half a revolution around the sleeve and completing the rotation with a suitably calibrated dynamometric wrench provided with a suitable bush; said operation allows for tightening and simultaneously tensioning the rope (3) in order to reduce its elasticity;
repeating the same operations for each pillar, also crossing all the lines on the same pillar, using the sleeves as needed, in order to obtain a network, as shown in Fig. 4.

In case of large surfaces, the operation can be partially carried out to obtain the network on a portion of the surface and can be repeated to obtain the network on the remaining portions.

Claims

Safety equipment for structures comprising at least one lower level (PI) and one upper level (PS) supported by a series of pillars (1) extending between said lower level (PI) and upper level (PS); equipment comprising:
- a series of uprights (2) with lower end section (2b) adapted to be fixed on top of a pillar (1) and with upper end section (2a);

- at least one horizontal rope (3) supported by one of said uprights (2) on its upper end section (2a);

- a sling (5) worn by the operator (6);

- a safety cable (4) with lower end (4b) fixed to said sling, and upper end (4a) slidingly fixed to said at least one horizontal rope (3); equipment comprising at least one tightening device (7) arranged on top of at least one of said uprights (2) to tighten a portion of the horizontal rope (3) supported by the upright (2) whereon the tightening device (7) is arranged; it being provided that said tightening device (7) is a tightening and tensioning device (7) of the horizontal rope (3) supported by it; said tightening and tensioning device (7) consisting in a sleeve inserted into the upright (2); equipment wherein:
- said tightening and tensioning device (7) consists in a sleeve (7) with circular section, provided with lower end (7a);

- said upright (2) has an upper end section (2a) provided with upper circular mouth (2c) adapted to house the lower end section (7a) of the tightening and tensioning device (7);

- said sleeve (7) comprises a pair of longitudinal notches (7e) adapted to house one of the horizontal ropes (3);

- locking means (7c, 9) are provided both on the lower end section (7a) of the sleeve (7) and on the upper end section (2a) of the upright (2); said means (7c, 9) mutually cooperating as soon as the sleeve (7) is completely inserted into the upright (2);

- equipment characterized in that it comprises a bush (T) adapted to be inserted, from up downwards, on said sleeve (7) and provided with:
- a top wall (T1) with side (T1 a) facing towards the sleeve (7) when the bush (T) is inserted onto the sleeve (7);

- a hole (T2) with square section obtained in central position with respect to said top wall (T1); said hole (T2) being adapted to house a square pin of a dynamometric wrench;

- at least one tooth (T3) protruding in lower position from said side (T1 a) and inserted into a notch (7e) of the pair of notches (7e) when the bush (T) is inserted onto the sleeve (7).
The equipment of claim 1, wherein said bush (T) has a side edge (T4) to which said at least one tooth (T3) is joined; said side edge (T4) surrounds and embraces the top section of the sleeve (7), when the bush (T) is inserted onto the sleeve (7).
The equipment of claim 1 or 2, wherein said bush (T) comprises two teeth (T3) in diametrically opposite position.
The equipment of claim 2 and 3, wherein said side edge (T4) of the bush (T) is provided with a notch (T5) perpendicular with respect to the top wall (T1), which houses the striker (9) when the bush (T) is inserted onto the sleeve (7).
The equipment of any one of the preceding claims, characterized in that said means (7c, 9) consist in a toothed profile (7c) obtained on the external surface of the lower end section (7a) of the sleeve (7), and a striker (9) arranged in correspondence of the upper end section (2a) of the upright (2) and provided with tip adapted to be engaged inside one tooth of said toothed profile (7c) as soon as the sleeve (7) is completely inserted into the upright (2).
The equipment of claim 5, wherein said sleeve (7) is provided with upper end (7b) for coupling with the lower end (7a) of an identical sleeve (7); it being provided that the sleeve (7) comprises means (7c, 9) obtained on the external surface of the lower end section (7a) of the sleeve (7), and in correspondence of the upper end section (7b) of the sleeve (7), which cooperate as soon as the sleeve (7) is completely inserted inside another identical sleeve (7).
The equipment of claim 6, wherein said means (7c, 9) consist in a toothed profile (7c) obtained on the external surface of the lower end section (7a) of the sleeve (7), and a striker (9) arranged in correspondence of the upper end section (2a) of the sleeve (7) and provided with tip adapted to be engaged inside one tooth of said toothed profile (7c) as soon as the sleeve (7) is completely inserted into another identical sleeve (7).
The equipment of any one of the preceding claims, comprising at least one bush (8) adapted to be fixed on top of the pillar (1) and provided with upper end (8a) defining a mouth (8b) wherein the lower end (2b) of an upright (2) is inserted.
The equipment of claim 8, comprising at least one substantially T-shaped plug (81) with vertical portion (81 a) adapted to be exactly inserted into the bush (8) and enlarged head (81 b) adapted to remain outside the bush (8) and rest on the mouth (8b) of the bush (8); said plug (81) comprising:
- a vertical portion (81 a) adapted to be completely and exactly inserted into the bush (8) passing through the mouth (8b) of the bush (8);

- an enlarged head (81 b) with lower stop surface (81 c) engaged at least partially above the mouth (8b) of the bush (8);

- two wings (81 d) protruding downwards from said enlarged head (81 b) and adapted to be arranged in side-by-side position close to the upper end (8a) of the bush (8) when the plug (81) is completely inserted inside the bush (8); the height (h) of said wings (81d) being identical to the height (h) of the upper end (8a) of the bush (8), which protrudes from the top (1 a) of the pillar (1) when the bush (8) is drowned inside the pillar (1).
The equipment of any one of the preceding claims, wherein said uprights (2) have a quadrangular section; said equipment comprising a stiffening rod (20) inserted externally onto an upright (2).