Device for protection against ice.

The present invention relates to a device to increase the security against major falling pieces of ice or hard-frozen snow or a combination thereof from elevated constructions, such as, e.g., bridge cables, walls, roofs, bridges and gutters or other objects such as, e.g., vehicles and parts thereof .

The background of the problem is that if surfaces, which in winter have been cooled down to temperatures around 0 ⁰ C and therebelow, are exposed to wet snow, supercooled and/or cool rain that in addition frequently is combined with strong winds from different directions, or cool oozing water, they becomes covered with a frozen-on layer of ice and/or hard snow. When it later becomes warmer, with an air temperature around 0 ⁰ C or thereabove or when the sun shines, the hard-frozen snow and/or ice melts and may leave hold of the surface it from the beginning was frozen fast to. The reason for this may, among other things, be that the surface emits, conducts or reflects heat so that the hard snow or ice comes loose from the surface and falls down as major or minor pieces and/or sheets, since nothing longer keeps them in place. In doing so, they may cause very serious accidents and injuries/damages, if they hit people, animals or objects. Solutions used today frequently consist of different kinds of heating to prevent freezing-on or by melting frozen-on surfaces and thereby keep the surfaces free from ice or snow covers. Differ- ent types of paints or coatings on the surfaces are also used to prevent covering of ice or snow. Devices that vibrate and stretch, respectively, e.g., wires being covered with ice are also used as well as baskets on the topside of the construe-

tions in question to prevent falling of major pieces of ice. However, the known constructions are expensive and not as efficient as desirable in order to fully solve said serious unde- sired problem with falling ice, hard-frozen snow or a combination thereof.

Therefore, the main object of the present invention is primarily to solve said problem readily, economically, safely and efficiently.

Said object is attained by means of a device according to the present invention, which substantially is characterized in that the construction in question is provided with an insulating surface on which ice, etc., is intended to form a cover and that said insulating surface has elements extending at an angle from the construction, which elements increase the area for ice to form a cover on, but which, as seen facing the surface of the construction in question, divide the same into smaller surface portions, thereby decreasing the risk of major falling portions of formed ice, etc.

Said object is also attained by means of a device according to the present invention, which substantially is characterized in that an external protection in the form of a net, grid or a similar penetratable surface is installed on the surface in question from which major portions of ice, etc., are intended to be prevented from falling, that said protection is arranged to be kept at a distance from said construction by means of elements extending at an angle from the construction, which elements form an insulation, and that said protection is arranged to retain major portions of formed ice, etc., but allow the passage of meltwater when the ice, etc., melts.

The invention is described below in the form of a number of preferred embodiment examples, reference being made to the accompanying drawings in which

Fig. 1 shows a cross section view of a bridge wire having a surrounding ice-fall protection,

Fig. 2 shows said protection schematically,

Fig. 3 shows a side view of said protection, Fig. 4 shows a protection having barbs,

Figs. 5-6 show a gutter ice protection,

Figs. 7-10 show different examples of spacer members having an appurtenant grid-shaped cover protection, wherein Fig. 7 shows an example of installing additional insu- lation between a construction and an external device, and

Figs. 11-12 show a cross section view and a perspective view, respectively, of an ice-fall protection surrounded by a wire.

According to the present invention, a device 1 to increase the security against major falling pieces of ice from elevated constructions 2, such as, e.g., bridge cables 2 ¹ , walls, roofs, bridges, and gutters 102 or other objects such as, e.g., vehicles and parts thereof, e.g., vehicle covers, trailers, cabins, etc., is arranged and intended to cover and surround the surface A of the construction 2 in question or the object desired to be protected against covering and falling of frozen fast ice and/or snow, with an external applicable insulating surface 3 of a thermally insulating suitable material arranged between the construction 2 and said surface A and/or device 1. The function of said insulating surface 3, which consists of an insulating material 3 ¹ , is substantially to delay the formation of an ice cover on the surface A at temperatures around 0 ⁰ C but instead at a lower temperature. When the temperature then falls a bit below 0 °C, now an ice cover is obtained that freezes fast to the covering insulating surface 3, such as ice would have done at a higher temperature directly on the construction 2 previously having it not been covered or surrounded by an insulating surface. Ice should also

be understood as hard-packed, hard-frozen snow or a combination of ice and snow.

It is also possible to cover the surfaces with, e.g., foil in order to alter the adhesion of the ice or for the deicing, e.g., metal foil, Teflon, paint, etc., and it is also made possible to allow heating of said surface in a known way.

Said insulating surface 3 may have elements 4 extending at an angle from the construction 2, which elements are intended to increase the area for the ice to get caught on and form a cover, but which, as seen facing the surface of the construction in question, divide the same into smaller surface portions, similar to ice-cube freezing trays, thereby decreasing the risk of major falling portions of formed ice. Said icecube freezing trays form cells 5. According to a preferred embodiment, the walls of said cells 5 may lean so that the opening 6 decreases in dimension as seen to the bottom 7 thereof. Then, the ice is retained efficiently. Said elements 4 may also have a plurality of angled barbs 8, which project from the elements 4. Said elements 4 and barbs 8 increase the area along which ice is capable of freezing fast to. When said ice melts, the barbs 8 contribute further to increase the capacity of retaining this ice at said elements 4 without falling down.

Examples of suitable thermally insulating materials are polyurethane foam, cellular plastic, glass fibre, mineral wool, natural fibre insulation, or some form of non- rigid plastic .

The elements 4 are, for instance, arranged to extend perpendicularly from the insulating surface 3, but they may also adopt other angles, e.g., within the interval of 60- 120°.

According to an embodiment of the present invention, outside and/or around the elements 4, there is preferably one or more nets 9 or a similar fine-meshed grid, which

covers the portions 11 of said construction 2 turned at least in the downward direction 10, and which is kept at a distance from the construction 2 by means of elements 4. Said elements 4 may, e.g., be in the form of cell walls 5. If it also is desir- 5 able to separate the elements 4 and the net 9, spacers in the form of, e.g., pins may be attached. Said spacers, having or not having barbs 8, have, in addition to the capability of keeping said parts spaced-apart from each other by means of the height thereof, also the capability of contributing to increase

LO the area that ice freezes fast to and, in that connection, also secure the ice, not at least thanks to the barbs 8.

The height of the elements 4, having or not having spacers, from the external insulation 3 of the construction should be at least 1/3 of the thickness of the expected

L5 ice cover. Then, the distances between the insulation 3 and the net 9 also become 1/3 of the expected covering of ice. When or if the space between the insulation 3 and the net 9 becomes entirely filled up with ice somewhere, the covering of ice may proceed to grow through the net 9 and further outside the net

20 9. In this connection, the net 9 forms a reinforcement for the ice that, in addition to being frozen fast to the insulation 3 and to the elements 4 and/or cells 5 frozen fast in ice and having or not having barbs 8, also has frozen fast in the net 9. The dimensioning and material of the net 9, as well as the

15 distance and mutual position between the threads included in the net 9, are adapted so that the net 9 is sufficiently strong to retain all ice that is expected to be formed between the construction 2 and the net 9 as well as outside the net 9 without being deformed, even if ice has left hold of the cells 5 or

10 elements 4 of the insulation, as well as not letting through any ice without it having melted into water or water vapour. When it becomes milder weather with temperatures around 0 ⁰ C or thereabove after a weather that has caused an ice cover on the

construction, ice begins to melt off from outside and inward, first toward the net 9, provided that the covering of the ice extends outside the net, and then further inward toward the insulation 3. By the fact that the insulation 3 is arranged on the outside of the intended surface intended to be protected, ice will leave hold of the insulation 3 later than ice would have done if it had been frozen fast directly against the construction 2 and if the same has emitted, conducted or reflected heat. Furthermore, there is ice frozen fast in cells 5 and/or elements 4 or is held by barbs 8 projecting from cells 5 and/or elements 4. If or when ice comes loose from the insulation 3, cells 5 and/or elements 4 or the barbs 8 possibly projecting therefrom, there is still ice armoured in the net 9 or is surrounded by the net 9, and therefore cannot fall down but is melted into water and water vapour between the insulation 3 and the net 9.

The surface that should be protected against covering of ice is surrounded by and is coated by a surface of thermally insulating material on which ice can form a cover. On the insulation 3, there are cells attached of the honeycomb type or another shape, e.g., angles, triangles, quadrangles, quintangles, longitudinal and/or transverse partition walls, etc., which project from the insulation 3 and in such a way increase the area that ice can freeze fast to. The above mentioned cells 5 may be smooth or provided with barbs, which, when ice or hard- frozen snow or a combination thereof melts, help to retain ice against the surface of the insulation 3 and/or against the surfaces of the walls of the cells without coming off and falling down. On the outside of and/or around said cells 5, a net 9 may be installed, and then said cells 5 keep the net 9 separated from the insulation 3 by the distance that the height of the cells gives.

Between the insulation 3 and the net 9, loose elements of varying shape may be installed, for instance angles, triangles, quadrangles, quintangles, etc., longitudinal and/or transverse partition walls, cylinders, cones, pyramids, cubes, etc., in order to keep the insulation 3 and the net 9 spaced-apart at the distance desired.

On the insulation 3, elements of the above shape and geometry may be attached and/or embedded that keep the insulation 3 and the net 9 spaced-apart at a desired dis- tance .

On the net 9, elements of the above shape and geometry may be attached and/or embedded that keep the insulation 3 and the net 9 spaced-apart at the desired distance.

The net 9 may surround or cover the insulation 3, or alternatively, in certain cases, the net 9 including the elements thereof may be used stand alone in order to directly surround or cover the construction 2.

The components the insulation 3, the net 9 and the elements 4 may also constitute a homogeneous unit espe- cially formed to surround or cover the construction 2, and/or be composed of a number of homogeneous units, which when interconnected surround or cover the construction 2.

It may also be shaped as a soft homogeneous unit, which directly may be formed against or around the con- struction 2 in question and cover the same.

The cells 5 and elements 4 have the purpose of increasing the area that ice can freeze fast to as well as to keep the insulation 3 and the net 9 spaced-apart at the distance previously determined, which should be approx. 1/3 of the thickness of the expected ice cover.

When some part of the space between the net 9 and the insulation 3 become entirely filled up with ice, the covering of ice can proceed to grow through the net 9 and fur-

ther outside the net 9. Then, the net 9 forms a roothold and a reinforcement for ice that, in addition to being frozen fast in the insulation 3 and/or cells 5 and/or elements 4, now also is frozen fast in the net 9 and armoured by the net 9.

5 The dimensioning and material of the net 9 are calculated in such a way that the net 9 holds for the load of the expected quantity of ice between the insulation 3 and the net 9 as well as the cover outside the net 9 without breaking or being deformed, even if ice entirely would leave hold of the

.0 insulation 3, the cells 5, the elements 4, or the barbs 8.

The distances between the tubes/threads/strings/strips included in the net 9 as well as the mutual position between them should be formed so that they form a pattern of a grid and/or net, through which wet snow,

.5 snow, supercooled rain, rain, meltwater, cold water easily can reach the surface of the insulation 3 and/or the cells 5 and/or the elements 4. In the area between the insulation 3 and the net 9, the ice forms a cover that may fill this space but also grow through the net 9 and outside the net 9, the net 9 armour-

!0 ing and retaining ice even if it has left hold of the insulation 3 and/or the cells 5 and/ or the elements 4. Said net or fine-meshed grid may be arranged to be formed of a plurality of smaller sections, which are assembled into a continuous larger net or grid.

!5 When ice melts, the net 9 is formed so that only very small fractions of ice should be allowed to pass through the net 9 without first melting into water or water vapour .

By the fact that the insulation 3 is of a i0 partly insulating nature or coated with an insulating layer between the construction 2 and the insulation 3, ice melts from outside and inward, first toward the net 9, provided that the coating of ice extends outside the net, and then toward the

insulation 3 and does not leave hold of the insulation 3 as easily as it could have done from the construction 2 having the construction 2 emitted, conducted or reflected heat from below against ice. Therefore, ice does not come loose as easily from 5 the insulation 3 and fall down. Furthermore, this is prevented by the surrounding or covering net 9 and/or barbs 8 of the elements 4.

In addition to be frozen fast on the insulation 3, ice is frozen fast on elements 4 and/or is secured by barbs

LO 8 projecting from elements 4, which barbs secure ice and stop the same from falling and may be surrounded by the net 9 as an additional safeguard.

In the drawings in Figs. 11 and 12, examples are shown of the application of a device 1 at a suspended

L5 bridge cable 2 having a surrounding net basket 9 and elements 4 in the form of longitudinal ridges and/or triangles distributed along the surface extension of said cable 2a in the longitudinal and/or transverse direction. Said spacers may also be cone- shaped and have a plurality of barbs 8 along the sides thereof.

20 Ice and/or hard-frozen snow are retained efficiently using said embodiment examples and work according to the principle of the invention given above, where the ice, etc., is retained in the formed cells 5. In that connection, the insulation may consist of, e.g., air in said elements 4, i.e., air pockets embedded in

15 the elements, or the elements may be manufactured from a suitable insulating material.

When, e.g., installing the net 9 having attached cells and/or elements around a gutter, see Fig. 5, parts of the net 9 may be without cells and/or elements and

ϊ0 reach above the gutter further up under the roof covering and be fixed there. In addition to preventing leaves and foreign objects from ending up in the gutter, then it also constitutes an additional safeguard against the construction 2, the insula-

tion 3 and the net 9 together with the ice cover would come loose by their own weight from the attachments thereof, or that the attachments would come loose from the attaching points and fall down. A device 1 to prevent falling of major portions of ice and the like from elevated constructions 2, such as has been mentioned above, comprises a protection 9 lying on the outside of the surface of said construction 2, which protection is installed by the attachment with, e.g., screws, glue, attaching devices, or by allowing to surround the construction 2 in question. Said protection is formed of a net 9, grid or any similar penetratable surface, and that said protection 9 is arranged to be kept at a distance from said construction 2 by means of elements 4 that also form insulation against the con- struction 2. Said protection 9 is arranged to retain major portions of formed ice but allow the passage of meltwater when the ice melts at higher temperatures.

In Fig 5, it is shown that spacers 104 and net 109 are arranged externally of the underside 150 of a gutter, the net 109 being arranged to be attached to the roof 151 of the house and extending along the top portion 152 of the gutter, and preferably being formed into an upstanding pointedly formed snow protection, and being attached to the batten 153 of the roof under the tiles 154 of the roof. In Fig 6, a variant is shown, not in accordance with the invention, having depending net 209 attached to the gutter 202 and arranged to form reinforcement for ice being formed at the gutter 202.

Finally in Fig 1, it is shown how two-part insulating parts, fitting the circumferential shape of the construction in question, e.g., bridge wires, and having a surrounding net 9, are arranged connectable and, by means of screws or other attaching means 12, are arranged for the forma-

tion of a surrounding insulating cage, and an insulating covering layer 3 of insulating material is arranged to form the core of the protection.

According to the invention, a construction 2 is provided with elements 4 that extend at an angle from the construction. Preferably, a layer of a thermally insulating material is arranged between the elements and the construction. Preferably, the elements, entirely or partly, consist of an insulating material. Preferably, there are different elements interconnected on the surface of the construction 2 and diving the same into smaller surface portions. Preferably, an external protection 9 in the form of one or more nets, grids or similar penetratable surfaces is installed at a distance from the construction. All features mentioned in the application may be combined freely.

The nature and the function of the invention should have been clear from what has been mentioned above and shown in the drawings, and the invention is naturally not limited to the embodiments described above and shown in the accom- panying drawings. Modifications are feasible, particularly as for the nature of the different parts, or by using an equivalent technique, without departing from the protection area of the invention, such as it is defined in the claims.