EP4682328A1

EP4682328A1 - Dissipation device for safety systems

Info

Publication number: EP4682328A1
Application number: EP25188744.4A
Authority: EP
Inventors: Stefano Duci; Giuseppe Lupi; Andrea Mazzoleni; Andrea SAVIO
Original assignee: Fin Group Srl
Current assignee: Fin Group Srl
Priority date: 2024-07-19
Filing date: 2025-07-10
Publication date: 2026-01-21

Abstract

The dissipation device (1) for safety systems comprises a main body (2) hookable to a supporting structure of a safety system, the main body (2) having a pair of lateral walls (3); a central wall (4) interposed between the lateral walls (3); a compartment (5) delimited by the walls (3, 4); a pair of weakening lines (6) obtained on the central wall (4) so as to define a tear portion (7); and a connection element (8) connected to the tear portion (7) and adapted to connect to a load.

Description

The present invention refers to a dissipation device for safety systems designed in particular to protect operators from the dangers of falling from a height. The dissipation device can be integrated in a lifeline, preferably horizontal, to reduce the force transmitted on the terminal elements in the event of an operator fall.
A lifeline is usually provided with a cable, generally made of high-strength steel or synthetic material, which serves as a continuous anchoring point for an operator. The ends of the cable are fixed to solid anchoring points. Between the cable and the anchoring point is placed a dissipation device which absorbs the energy generated by the operator's fall, reducing the impact on the operator and on the anchorings.
Various types of dissipation devices are known that differ mainly in relation to the principle used: spring dissipators exploit the deformation of the spring; wedge dissipators exploit the movement of a wedge through a resistant material; sheet metal dissipators absorb energy by flattening a bent metal sheet or fracturing sectors of the metal sheet.
The known dissipation devices are subject to ongoing improvement to enhance the performance thereof: an ideal dissipation device should provide the best possible dissipation, balancing the need to arrest the operator's fall in the smallest space possible and the need not to excessively stress the anchoring points.
The known devices are designed by means of complex analyses according to requirements and specific forces, and they are therefore difficult to adapt to different situations.
The object of the present invention is to provide a dissipation device able to optimize and improve the energy dissipation.
A further object is to provide a dissipation device which is easy and simple to produce.
A further object is to provide a dissipation device which has a reduced production cost.
A further object is to provide a dissipation device with reduced overall dimensions.
Said objects are achieved by a dissipation device for safety systems comprising a main body adapted to be hooked to a supporting structure of a safety system, the main body having a pair of lateral walls opposite each other and extending in a longitudinal direction; a central wall interposed between the lateral walls and extending in said longitudinal direction; a cavity delimited by the walls; a pair of weakening lines obtained on the central wall and extending in the longitudinal direction so as to define between them a tear portion; and a connection element connected to the tear portion and facing the cavity, the connection element being adapted to connect to a load.
Said objects are further achieved by a safety system comprising at least a supporting structure, a support element adapted to support and/or receive a load, and a dissipation device, the dissipation device being interposed between the supporting structure and the support element.
Further characteristics of the invention are described in the dependent claims.
This solution has several advantages with respect to the solutions of the known art.
Due to the characteristics of the dissipation device, the force used for dissipation tends to be substantially constant. In a dissipator, in fact, there are usually two parameters to be evaluated: the energy absorbed per unit of space and the force discharged onto the supporting structure. The Applicant has found that the use of a constant force for the dissipation allows these two parameters to be optimized.
Furthermore, due to the ease with which said dissipation device can be made, it is easy to adjust its characteristics to adapt to different operating needs, without requiring excessively complex production processes.
The device can be quickly installed by a user since it can be easily pre-assembled prior to installation. The user therefore only has to fix it to the supporting structure.
The characteristics and advantages of the present invention will be evident from the following detailed description of a practical embodiment thereof, illustrated by way of non-limiting example in the attached drawings, in which:

figure 1 shows a perspective view from above of a dissipation device in accordance with the present invention;
figure 2 shows a view from below of the dissipation device of figure 1;
figures 3 and 4 show two different embodiments of the fixing elements of the reinforcement plate.

Referring to the attached figures, the number 1 indicates a dissipation device for safety systems.
The dissipation device 1 allows dissipation of the forces generated by a load in emergency situations such as, for example, an operator or a stored product falling from a height.
The safety system, in which the device 1 can be integrated, comprises a supporting structure, which can be secured to or rested on a structural element (for example a roof or the ground), and a support element such as, for example, a cable or a rope, adapted to support and/or receive a load.
As can be seen from figure 1, the dissipation device 1 comprises a main body 2 adapted to be hooked to the supporting structure of the safety system.
The main body 2 has an elongated shape that extends in a longitudinal direction L. In other words, the main body 2 extends mainly along its longitudinal direction L. Said longitudinal direction L is substantially rectilinear, allowing substantially constant and easily determinable dissipation of the forces, as will be seen below.
The main body 2 is made of at least one material chosen from stainless steel, carbon steel or aluminium. In the preferred version, the main body 2 is made of stainless steel.
In cross section, the main body 2 has a substantially C-shaped conformation.
Therefore, the main body 2 has a pair of lateral walls 3 opposite each other. Said lateral walls 3 extend in the longitudinal direction L.
The lateral walls 3 are specular to each other with respect to the centre line of the main body 2. Preferably, the lateral walls 3 are substantially parallel to each other.
Each lateral wall 3 has a shaped terminal edge 3a, shown in figure 2, which gives it a variable height.
The main body 2 comprises a central wall 4 interposed between the lateral walls 3 and extending in the longitudinal direction L. The central wall 4 extends in a substantially rectilinear manner. In particular it extends between two of its ends: an initial end 4a and a final end 4b.
The central wall 4 has a substantially flat shape.
The central wall 4 is arranged perpendicular to the lateral walls 3, giving the main body 2 a substantially C-shaped profile in cross section.
As will be understood from the following part of the description, said conformation of the main body 2 gives greater rigidity to the structure of the device 1 so that, during dissipation of the force, the main body 2 remains in a parallel position with respect to the force exerted by the load (for example remaining parallel to a connection cable described further on).
The main body 2 is obtained from a metal sheet, which is machined, for example by laser cut, and bent to obtain the final shape. Said process allows the device to be made in a simple inexpensive manner, in terms of both production and assembly, while maintaining a high operating efficiency.
The main body 2 is a single body. The lateral walls 3 are therefore continuous with the central wall 4 and are substantially perpendicular to the latter.
The walls 3, 4 delimit a compartment 5 which acts as a guideway in the longitudinal direction L for a support element configured to hook and support a load. Said support element is therefore housed in the compartment 5. The compartment 5 can also house and protect other operating elements of the device 1.
Due to the presence of the lateral walls that laterally delimit the compartment 5, the hooking to the load is offset with respect to the central wall 4, on which a tear plane is provided (described in detail further on in the description). Due to this expedient, during the tear, the torn portion is squashed on the cable, without "rearing up", thus permitting uniform dissipation throughout the length of the tear.
Advantageously, the main body 2 has a pair of weakening lines 6 obtained on the central wall 4 which extend in the longitudinal direction L so as to define between them a tear portion 7. The weakening lines 6 weaken the edges of the tear portion 7, which can thus be gradually torn from the central wall 4.
The extension of the weakening lines 6 defines the tear direction of the tear portion 7. The beginning and the end of the weakening lines 6 define, respectively, the initial terminal end 7a and the final terminal end 7b between which the tear portion 7 extends, which are obtained respectively in the vicinity of the initial end 4a and the final end 4b of the central wall 4. Preferably, the final terminal end 7b is obtained spaced from the final end 4b of the central wall 4, so that it can remain connected to the main body 2.
In one version, the weakening lines 6 are obtained by removal of material from the central wall 4 to reduce the thickness thereof.
In one version, the weakening lines 6 are obtained via a series of holes in the central wall, aligned and spaced from one another.
As already mentioned, the main body 2 comprises a connection element 8 connected to the tear portion 7, preferably at the initial terminal end 7a, and faces towards the compartment 5. In particular, the connection element 8 is integral with the tear portion 7.
The connection element 8 is an appendage of the central wall 4 which is bent towards the inside of the compartment 5, preferably perpendicular to the central wall 4. The connection element 8 is arranged housed in the compartment 5.
The connection element 8 is adapted to be connected to a load having force to be dissipated, for example by the interposition of a support element such as, for example, a cable or a beam.
The connection element 8 is intended to be stressed by the force to be dissipated, with at least one component directed parallel to the longitudinal direction L, with orientation going from the initial end 4a to the final end 4b. When a force is exerted on the connection element 8, the tear portion 7 is torn, dissipating said force.
This expedient allows the production of a dissipator in which the force that counters the load force is substantially constant along the extension of the tear portion 7.
The dimensions of the main body 2 can vary according to the energy to be dissipated, for example by adjusting the ratio between the thickness of the central wall 4 and the depth of the weakening lines 6, and/or by varying the length and/or width of the tear portion 7.
Due to the way in which the main body 2 is made, the device 1 can be easily produced with different dimensions and/or characteristics as required.
In one embodiment, not illustrated in the figures, the dissipation device 1 is intended to dissipate the force generated by a falling load which is received by a rigid support element following a fall such as, for example, a movable vertical beam.
The connection element 8 of the dissipation device 1, in said version, is rigidly fixed to the support element.
In the embodiment illustrated in the figures, the dissipation device 1 is intended to be integrated within a safety system of the lifeline type, and is therefore configured to dissipate forces of a load connected by means of a cable.
In said embodiment, the dissipation device 1 comprises a carriage 9 constrained to the connection element 8 and configured to receive and block a cable. The use of said carriage 9 also in other embodiments for fixing to other types of loads to be dissipated is not excluded. The carriage 9 is housed in the compartment 5 to slide in the longitudinal direction L. In particular, the lateral walls 3 contain and guide the carriage 9 along the compartment 5.
The carriage 9 is made by means of a plate 10 having a shape complementary to the compartment 5, housable in the latter.
The carriage 9 comprises a reception portion 11 adapted to receive and block the cable. The reception portion 11 has a through hole for the passage of the cable.
The reception portion 11 comprises a blocking means 12 of the cable such as, for example, a quick link or an eye bolt. The blocking means 12 is positioned in the hole. The blocking means 12 is of the self-blocking type, namely it allows the cable to be inserted in a direction, opposite to that of the force to be dissipated, and blocks the movement of the cable when it moves in the direction of the force to be dissipated.
The blocking means 12 preferably has a funnel-shaped body, where the larger diameter portion faces the connection element 8.
The carriage 9 comprises a connection portion 13 connected to the connection element 8. The connection portion 13 is arranged opposite the reception portion 11. The connection portion 13 comprises a hole for receiving fixing means for fixing to the connection element 8.
The dissipation device 1 comprises tensioning means 14 operatively connected to the carriage and configured to vary the tension of the cable (tensioning) when the latter is received and blocked by the carriage 9. Said tensioning is carried out by varying the distance between the carriage 9 and the connection element 8.
Said means allow the cable tension to be varied simply and rapidly.
The tensioning means 14 are interposed between the connection element 8 and the carriage 9 to connect them.
The tensioning means 14 comprise a movement element 15 connected to the carriage 9, and configured to move the carriage 9 nearer to/away from the connection element 8.
The movement element 15 comprises a pin 16 helically coupled with the connection element 8 and the carriage 9 by means of respective threads. By rotating the pin 16 in one direction or the other, the carriage 9 can be moved nearer to/away from the connection element 8. Preferably, the threads are such that, when the pin 16 is rotated, the carriage 9 moves in the longitudinal direction L in a direction contrary to the direction of movement of the pin 16. In practice, when the pin 16 is rotated in an approach direction, it slides in the longitudinal direction L in the direction of the force to be dissipated, and the carriage 9 slides on it in the opposite direction to move near to the connection element 8. The movement of both will therefore be opposite when it is rotated in the opposite distancing direction.
The connection between the pin 16 and the connection element 8 is strengthened by the presence of a reinforcement plate 17 positioned in contact with the connection element 8.
The reinforcement plate 17 also has a through hole centred with the hole of the connection element 8, thus allowing the passage of the pin 16 towards the carriage 9.
The reinforcement plate 17 is connected to the main body 2 by means of a fixing element 18. In particular, the fixing element 18 is adapted to maintain the reinforcement plate 17 in abutment and in contact with the connection element 8. The fixing element 18 preferably comprises a pair of tabs 18 which are obtained on either the reinforcement plate 18 or the main body 2 and connect to the other between the reinforcement plate 18 and the main body 2. The reinforcement plate 17 and the pair of tabs 18 provide further resistance to the force to be dissipated.
Figure 3 illustrates a first embodiment in which the pair of tabs 18 are obtained on the main body 2 and are bent towards the reinforcement plate 17 to abut against the latter.
Figure 4 illustrates an embodiment in which the pair of tabs 18 are obtained on the reinforcement plate 17. They protrude towards the main body 2. In the main body 2, respective slots are obtained in which the tabs 18 are inserted.
The reinforcement plate 17 also acts as a fall indicator: on the main body 2, preferably at one of the lateral walls 3 or both, a window 26 is obtained which allows a user to see the positioning of the reinforcement plate 17; the positioning of the window 26 and the reinforcement plate 17 is such that when the device 1 is not operating to dissipate a force, the reinforcement plate 17 is fully visible from the window 17; when, on the other hand, the device 1 has been activated, the reinforcement plate 17 disappears at least partly, or completely, from view, indicating that the device has been used.
The tensioning means 14 also comprise a spring 19, or more generally an elastically deformable element, interposed between the connection element 8 and the pin 16. The spring 19 is configured to elastically deform, preferably in compression, when the carriage 9 is moved in the longitudinal direction L in the direction of the force to be dissipated. The spring 19 is positioned so that it compresses when the pin 16 is rotated in the approach direction and decompresses when it is rotated in the distancing direction.
The spring 19 at the same time facilitates adjustment of the cable tension and provides an additional dissipation force.
The spring 19 winds around a portion of the pin 16 and is positioned on the other side of the connection element 8 with respect to the carriage 9.
The spring 19 is arranged in abutment against the connection element 8, and is constrained to the pin 16 by a bolt. The bolt allows the use of a screwdriver to rotate the pin 16, facilitating the tensioning operations.
The lateral walls 3 comprise respective extensions, beyond the initial end 4a of the central wall 4. Said extensions enclose and contain part of the tensioning means. In this case, the extensions enclose in particular the spring 19 and the portion of the pin 16 around which it winds.
The dissipation device 1 comprises measuring means 20, arranged partly on the main body 2, adapted to measure the cable tension.
The measuring means 20 comprise a graduated scale obtained on the main body 2 and extending beside a part of the movement element 15. The graduated scale is preferably obtained on the extension of one of the lateral walls 3.
The graduated scale is obtained by means of a laser incision in the longitudinal direction L. On the pin 16, an indicator is fixed, preferably a plate, which slides with the pin adjacent to the graduated scale to indicate the tension variation. Measuring means are thus provided via a simple effective solution.
However, the graduated scale can also be obtained on the pin 16 and the indicator can be positioned on the main body 3.
The dissipation device 1 comprises hooking means 22 connected to the main body 2 and configured to hook to the supporting structure of a safety system.
The hooking means 22 comprise a base structure 23 which is fixed to the main body 2 and is adapted to be constrained to a supporting structure by fastening means like screws or similar. The base structure 23 is fixed to the lateral walls 3 of the main body 2, preferably at the extensions described above, so as to keep them in position.
Appropriately, the dissipation device 1 comprises an anti-tamper assembly 24 which is adapted to be mounted on the tensioning means 14. Said anti-tamper assembly 24 is mounted after installation of the dissipation device 1 and tensioning of the cable. The anti-tamper assembly 24 comprises one or more elements configured so that they can be mounted only once. To be removed, said elements have to be broken. Preferably, said elements are an anti-tamper band mountable by means of an anti-rotation plate associable with the pin 16.
The present invention also concerns a safety system, not illustrated in the figures, which comprises a supporting structure, a support element adapted to support and/or receive a load, and the dissipation device 1 described above. The dissipation device 1 is interposed between the supporting structure and the support element. The dissipation device 1 is fixed so that its longitudinal direction L is arranged in the direction of the force that will be generated by the load.
In the preferred version, the safety system is of the lifeline type, namely the supporting structure comprises at least one structural anchoring, while the support element comprises a cable connectable to the structural anchoring and adapted to hook to an operator by means of a harness. The dissipation device 1 is hooked to the structural anchoring, while the connection element 8 is fixed to the cable.
Preferably, the safety system is a horizontal lifeline, namely it comprises at least a pair of anchorings and the cable extends horizontally between the pair of anchorings. The dissipation device is preferably associated only with one of the anchorings. The presence of one dissipation device for each anchoring is not excluded.
The operation of the invention is evident to a person skilled in the art from what has been described and in particular is the following. The following description refers to the case of a safety system of the lifeline type. When an operator secured to the lifeline falls, the safety cable exerts a force on the connection element in the longitudinal direction L. Initially, said force compresses the spring 19, and then causes breakage of the tear portion 7 at the weakening lines 6. The breakage is substantially continuous until the extension of the weakening lines 6 finishes or the force applied terminates.
The system thus conceived is subject to numerous modifications and variations, all falling within the scope of the inventive concept; furthermore, all the details can be replaced by technically equivalent elements.

Claims

Dissipation device (1) for safety systems, comprising a main body (2) adapted to be hooked to a supporting structure of a safety system, said main body (2) having:
- a pair of lateral walls (3) opposite each other which extend in a longitudinal direction (L);

- a central wall (4) interposed between said lateral walls (3) and which extends in said longitudinal direction (L);

- a compartment (5) delimited by said walls (3, 4);

- a pair of weakening lines (6) obtained on said central wall (4) which extend in said longitudinal direction (L) so as to define between them a tear portion (7); and

- a connection element (8) connected to said tear portion (7) and facing said compartment (5), said connection element (8) being adapted to connect to a load.
The dissipation device (1) according to claim 1, characterized in that said central wall (4) extends in a substantially rectilinear manner.
The dissipation device (1) according to one of the preceding claims, characterised in that said weakening lines extend substantially parallel to said longitudinal direction (L).
The dissipation device (1) according to one of the preceding claims, characterised in that it comprises a carriage (9) constrained to said connection element (8) and configured to receive and block a cable of a safety system; said carriage (9) being housed in said compartment (5) to slide in said longitudinal direction (L).
The dissipation device (1) according to claim 4, characterised in that it comprises tensioning means (14) operatively connected to said carriage (9) and configured to vary the tension of said cable when the latter is received and blocked by said carriage (9).
The dissipation device (1) according to claim 4 or 5, characterised in that said tensioning means (14) comprise a movement element (15) connected to said carriage (9); said movement element (15) being configured to move said carriage (9) closer to/away from said connection element (8).
The dissipation device (1) according to the preceding claim, characterised in that said movement element (15) comprises a pin (16) helically coupled to said connection element (8) and to said carriage (9) by means of respective threads; said threads being such that when said pin (16) is rotated, said carriage (9) moves in said longitudinal direction (L) in a direction contrary to the direction of movement of said pin (16).
The dissipation device (1) according to claim 6 or 7, characterised in that said tensioning means (14) comprise an elastically deformable element interposed between said connection element (8) and said movement element (15); said elastically deformable element being configured to elastically deform when said carriage (9) is moved in the longitudinal direction (L) in the direction of the force to be dissipated.
A safety system comprising at least a supporting structure, a support element adapted to support and/or receive a load, and a dissipation device (1) according to one or more of the preceding claims, said dissipation device (1) being interposed between said supporting structure and said support element.
The safety system according to claim 9, wherein said supporting structure comprises at least a structural anchoring, and wherein said support element comprises a cable connectable to said structural anchoring and adapted to hook to an operator by means of a harness; said dissipation device being hooked to said structural anchoring and said connection element (8) being connected to said cable.