LIGHT TRANSMITTING THREE-DIMENSIONAL OBJECT AND METHOD FOR MANUFACTURING THE SAME

The invention relates to a light transmitting three-dimensional object and to a method for manufacturing a light transmitting three-dimensional object.

On the one hand, the light transmitting three-dimensional objects of the invention belong to the objects being denoted in the art by the term "glass-concrete" and known for decades. These are e.g. such industrial glass-concrete panels or even objects of applied art that comprise glass elements embedded in concrete optionally reinforced by steel. At the same time, the materials constituting glass-concrete, i.e. the glass, the concrete and the steel, can be substituted by other materials of similar properties; thus the glass can be substituted by another transparent material and the concrete can be substituted by any other material being substantially non-transparent that is shapable, pourable initially but solidifies after pouring in progress of time or as a result of some treatment. The same way, the steel reinforcing can be replaced by another material of suitable mechanical strength. That is, instead of glass e.g. Plexiglas or other transparent plastic material, optical light guide fibres, instead of conventional concrete e.g. artificial stone, resin bonded artificial stone or non-transparent plastic material, instead of the steel reinforcing e.g. carbon fibre reinforcing or steel fibre reinforcing (fibre concrete) can be used so that the properties and the manufacturing method of the light transmitting three-dimensional object substantially remains the same as that of glass-concrete. The present invention embraces the usage of the above mentioned and other similar materials as well as the combinations thereof.

On the one hand, the three-dimensional object embodying the present invention can be used as a building block for constructing larger light transmitting objects (e.g. walls) or, on the other hand, it can be used in itself e.g. as a shelf, a table-board or a tombstone, just to mention a few of the potential applications.

The conventional manufacturing method of glass-concrete and glass-concrete that can be produced thereby are disclosed in Die Welt der Glasfenster — Zwolf Jahrhunderte abend- landischer Glasmalerei (Herder Verlag, Freiburg, 1977) of George SEDDON et al. The

method comprises the steps of arranging glass elements and steel reinforcing providing the bearing capacity of the finished structure in the bottom of a casting tray and pouring concrete (or synthetic resin) into the gaps between the glass elements. The glass elements are cut or cracked away from stained or uncoloured glass panels of a thickness between 2 and 5 centimetres, typically. Expediently, the glass elements are temporarily fastened to the bottom of the casting tray by means of adhesive bonding in order to prevent the poured in concrete from entraining the glass elements. After the setting of the concrete the glass-concrete can be removed from the mould, which glass-concrete is thin, "two- dimensional" and resembles leaded stained glass panels, due to the given thickness of the glass. This technology is incapable of the production of "spatial" glass-concrete objects, i.e. objects having substantial height because the tall glass elements having small contact surfaces as compared with their height could only be fastened to the bottom of the casting tray rather cumbersomely for the time the concrete is being poured. Accordingly, this method does not facilitate efficient mass production.

Glass-concrete objects substantially as described above are disclosed in Hungarian utility model No. 2 365 U of the present applicant.

Another known group of glass-concrete or glass-ferroconcrete objects is composed of walls, floors or ceilings constructed from glass-bricks joined by means of concrete reinforced by steel; these usually range in thickness from 8 to 15 centimetres (see e.g. Gustl SCHIEB: Das Fachbuch des Glashandwerkes L, p. 268 to 278, Osterreichischer Gewerbeverlag, Wien, 1958).

Disclosed in GB patent No. 1 561 142 is a decorative ceiling, wall or floor panel and a ceiling, wall or floor constructed from these panels, wherein one or more light-conducting rod is penetrated through the panels posteriorly. Coloured lamps spotlighting the light- conducting rods are arranged behind the ceiling, wall or floor constructed from the panels. Manufacturing of the panels comprises the step of drilling through the otherwise finished ceiling, etc. panels and inserting the light-conducting rods.

International patent publication pamphlet No. WO 03/097954 discloses a moulded rectangular building block, wherein light transmitting fibres extending between two opposite lateral surfaces of the block are embedded in the material thereof. The manufacturing of the building block comprises the steps of pouring cast material into an elongated mould, arranging a plurality of parallel light transmitting fibres on the cast material, pressing the fibres into the cast material by means of vibration and/or mechanical pressure. These steps are repeated and finally the solidified body is partitioned into building blocks. Carrying out the method described above results in a building block in which the light transmitting fibres are evenly and at the same time randomly distributed and similarly, the two ends of the fibres are evenly and randomly distributed over the two lateral surfaces; this method is incapable of manufacturing a three-dimensional object, wherein the embedded light transmitting elements constitute a pattern or wherein the transparent elements giving life to a lighting effect are not only present on the two opposing surfaces of the object. Furthermore, by increasing the fibre- to-concrete ratio, the mechanical strength of the building block will become deteriorated, which constitutes another drawback.

In all of the light transmitting three-dimensional objects above the integrity of the three- dimensional object is ensured by the non-transparent material (e.g. concrete), i.e. the non- transparent material holds together the transparent elements, which provision imposes a rather strict constraint on the design options of the light transmitting three-dimensional objects.

An object of the present invention is to provide a method for manufacturing a light transmitting three-dimensional object, capable of the production of not only the well- known "two-dimensional" objects that can be transilluminated from two sides or the objects comprising only homogenously and randomly distributed glass fibres ending up on only two lateral surfaces thereof, but which method facilitates the manufacturing of light transmitting three-dimensional objects of virtually arbitrary design regarding both the spatial configuration thereof and the appearance and arrangement of the transparent elements on the surfaces of the objects. Another object of the invention is to allow the transillumination of the three-dimensional object in more than one direction as desired.

Another object of the invention is to allow the ratio of the transparent part to the non- transparent part in the three-dimensional object to be increased, i.e. to increase the degree of light permeability thereof without the deterioration of the load-bearing capacity of the three-dimensional object. Another object of the invention is to provide a method that facilitates efficient mass production. Another object of the present invention is to provide the light transmitting three-dimensional object itself being in accordance with the above objects.

These objects can be attained by means of providing a light transmitting three-dimensional object and a method for manufacturing a light transmitting three-dimensional object defined in the independent claims. Some preferred embodiments of the three-dimensional object and the method are disclosed in the independent claims.

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which

figure 1 is a perspective view of a skeleton consisting of transparent elements as inserts, that can be embedded into a light transmitting three-dimensional object according to a first embodiment of the invention;

figure 2 is a perspective view of the light transmitting three-dimensional object of the invention, incorporating the skeleton shown in figure 1;

figure 3 is a side elevation view of a skeleton consisting of transparent elements and connecting elements as inserts, that can be embedded into a light transmitting three-dimensional object according to a second embodiment of the invention;

figure 4 is a top plan view of the skeleton shown in figure 3;

figure 5 is a perspective view of the light transmitting three-dimensional object of the invention, incorporating the skeleton shown in figures 3 and 4;

figure 6 is a side elevation view of a skeleton consisting of transparent elements, connecting elements and anchoring elements as inserts, that can be embedded into a light transmitting three-dimensional object according to a third embodiment of the invention;

figure 7 is a top plan view of the skeleton shown in figure 6;

figure 8 is a perspective view of the light transmitting three-dimensional object of the invention, incorporating the skeleton shown in figures 6 and 7;

figure 9 is a side elevation view of an anchoring element connected to transparent element;

figure 10 is a cross sectional view of a skeleton consisting of transparent elements and connecting elements as inserts, that can be embedded into a light transmitting three-dimensional object according to a fourth embodiment of the invention;

figure 11 is a perspective view of the light transmitting three-dimensional object of the invention, incorporating the skeleton shown in figure 10;

figure 12 is a cross sectional view illustrating another possible example of the engagement of transparent elements and connecting elements;

figure 13 is a perspective view of a fifth embodiment of the light transmitting three- dimensional objects of the invention;

figure 14 is a top plan view of a skeleton consisting of transparent elements as inserts, that can be embedded into a light transmitting three-dimensional object according to a sixth embodiment of the invention;

figure 15 is a perspective view of the skeleton shown in figure 14; and

figure 16 is a perspective view of the light transmitting three-dimensional object of the invention, incorporating the skeleton shown in figures 14 and 15.

The three-dimensional object and the method of the invention will be described now by referring firstly to figures 1 and 2 showing a first embodiment of the light transmitting three-dimensional object 2. Some transparent elements 1 are provided, that are desired to be embedded in the substantially non-transparent solid material 3 of the finished light transmitting three-dimensional object 2 as inserts. In this case twenty-one glass rods having square cross section are provided. Among these, the length of nine glass rods is equal to the height of the desired light transmitting three-dimensional object 2, while that of six glass rods is equal to the width thereof and the length of six glass rods is equal to the width thereof. In accordance with the present invention, these transparent elements 1 are fastened together so that they will be able to form a skeleton 5 for the light transmitting three-dimensional object 2. Particularly, an orthogonal lattice structure is formed from the glass rods as shown in the figure. In this embodiment the glass rods can be fastened together by means of a transparent adhesive material, e.g. a silicone-based adhesive material providing flexible bond. An example for silicone-based adhesives is Mapesil. Thus, an arrangement of the inserts, i.e. the transparent elements 1 is formed in accordance with their position as required in the finished light transmitting three- dimensional object 2. Therefore, the skeleton 5 comprising the inserts has become completed and it can be placed into a mould of a shape corresponding to the desired light transmitting three-dimensional object 2; in this case the mould is block shaped and it can be e.g. an openable mould made of steel.

First of all, the inner surface of the mould is preferably covered with separating agent, and in a preferred embodiment of the method of the invention the substantially non- transparent material 3, e.g. freshly mixed concrete is poured into. In a preferred embodiment, the composition of concrete is one part binder — in this case cement — , two parts aggregate — finely-granular gravel — and water. Then the assembled skeleton 5 is sunk into the concrete, which infiltrates the gaps between the glass rods and, lastly, it fills all available space. After its insertion, the skeleton 5 is positioned in the mould in such a way that the transparent elements 1 will get to their required locations. In the present

highly preferred example, when inserting the skeleton 5 into the mould, the ends of the glass rods contact the inner surface of the mould and the skeleton 5 actually positions itself and become stuck in the mould. Additionally, the poured quantity of the concrete is so determined that the level of the concrete will be flush with the upper ends of the glass rods. As a result, the ends of the glass rods will be present on the faces of the finished light transmitting three-dimensional object 2.

In another embodiment of the method, the skeleton 5 is placed into the mould firstly and the material 3, i.e. the concrete is poured thereinto afterwards. It is also possible, of course, that only a part of the material 3 is poured in, then the skeleton 5 is inserted and the pouring of the material 3 is continued afterwards.

It is not inevitable to put all of the inserts intended to be arranged in the light transmitting three-dimensional object 2 into the mould as a part of the skeleton 5 but other inserts, e.g. other transparent elements (not shown) independent of the skeleton 5 may also be inserted prior to, during or after pouring. It is also possible to place more than one independent skeleton 5 into the same mould.

The poured material 3, i.e. the concrete can be compacted e.g. by means of vibration or compressing as required, it is allowed to set and cured by watering. When using other material 3 than concrete, the step/s needed for its solidification is/are performed as required. The light transmitting three-dimensional object 2 that has been hardened is removed from the mould then. The finished light transmitting three-dimensional object 2 is shown in figure 2.

In some embodiments the further processing of the body removed from the mould may be necessary to remove the material 3 unnecessarily covering the transparent elements 1 from the surface of the light transmitting three-dimensional object 2 on the one hand or e.g. to part a large object produced by a single pouring into several light transmitting three-dimensional objects 2 on the other hand, i.e. to finish the light transmitting three- dimensional object 2. Thus, directly after pouring or after the steps described above the transparent elements 1 are present on the surface of the light transmitting three-

dimensional object 2 — or, in other words, the surface of the light transmitting three- dimensional object 2 is partly formed by a part of the surface of the transparent elements 1 — in order to complete their task, i.e. to transmit light through the light transmitting three-dimensional object 2. The so obtained light transmitting three-dimensional object 2 may be subjected to further processing, surface treatment (e.g. grinding, sandblasting, polishing, roughening, drilling, etc.) in order to perform some kind of decorative purpose.

In the finished light transmitting three-dimensional object 2, due to the presence of the skeleton 5 it does not devolve on the non-transparent material 3, i.e. the concrete to hold together the inserts and to ensure the integrity of the whole light transmitting three- dimensional object 2; this task is completed by the skeleton 5. Thus, light transmitting three-dimensional objects 2 having suitable strength for the bearing loads that may occur in building industry can be produced even without further reinforcing, however, it is also possible to embed steel reinforcing elements as further inserts in the material 3 either as a part of the skeleton 5 or being independent therefrom.

Lastly, it is to be noted that due to the skeleton 5 composed of transparent elements 1 being fastened to each other by means of transparent adhesive, the light can get from any faces of the light transmitting three-dimensional object 2 to any other faces thereof.

Adhesive bonding of the inserts to each other may be substituted in a variety of ways. In the present embodiment, e.g. the transparent elements 1 that has been put together to form the skeleton 5 but has not been glued together can be placed into a kiln where they can be fastened together by melting the surfaces thereof in a temperature of 600 to 800 ⁰ C, depending on their thickness (bonding by heat). Similar result can be obtained by casting the skeleton 5 — comprising the transparent elements 1 — in its required shape. In these cases, when cooling the skeleton 5, provisions have to be made for the suitable stress relieving to prevent its failure due to the stresses applied during the setting of the material 3. In case of a skeleton 5 obtained by gluing together glass rods, no further stress relieving is required.

Referring now to figures 3 to 5, in a second embodiment of the invention a first group of the insert being embedded in the substantially non-transparent material 3 of the light transmitting three-dimensional object 2 is composed of four transparent elements 1, i.e. glass rectangles cut from sheet glass and having equal size. Another group of the inserts is composed of connecting elements 4, i.e. twelve glass squares being cut from the same sheet glass. E.g. when a light transmitting three-dimensional object 2 of the same size as the well-known standard brick (250 mm X 120 mm X 65 mm) is intended to be made, the size of the glass rectangles can be 120 mm X 250 mm with a thickness of 9 mm while the size of the glass squares is 30 mm X 30 mm.

In accordance with the present invention, the transparent elements 1 — lying in parallel planes — are fastened to each other, in this case, by means of the connecting elements 4 as shown in the figure, forming the skeleton 5 of the light transmitting three-dimensional object 2. I.e., fastening to each other is achieved by bonding four connecting elements 4 between each two adjacent glass panels forming the transparent elements 1. Bonding may be realized again by a transparent adhesive providing flexible bonding, e.g. a silicone- based adhesive. Thus, the skeleton 5 comprising the transparent elements 1 and the connecting elements 4 is ready to be used to produce the light transmitting three- dimensional object 2 in a similar manner as described in connection with the first embodiment. When inserting the skeleton 5 into the mould, it is positioned such a way that the edges of the transparent elements 1 as well as the outer surfaces of the external transparent elements 1 come into contact with the inner surface of the mould. The finished light transmitting three-dimensional object 2 is shown in figure 5.

The skeleton 5 used in this embodiment and having layered structure has also divided the substantially non-transparent solid material 3 into layers and the adjacent layers of the skeleton 5 hold the material 3 in between. As the inserts forming the skeleton 5 are fastened together, the skeleton 5 maintains the integrity of the light transmitting three- dimensional object 2. Although the skeleton 5 of this structure itself is loadable, the concrete having been set between the inserts forming the skeleton 5 strengthens, rigidifies it. The glass elements and the concrete between the glass layers together forms a rigid and load bearing structural element that can be used e.g. for building a wall. Additionally,

another advantage of dividing the concrete into thin layers is that the shrinkage accompanying the hardening of concrete is proportionally smaller.

It should be noted that the inserts are actually arranged also in layers in the first embodiment, more particularly, the vertical glass rods hold together the glass rods extending in two perpendicular directions in horizontal layers 31, 32. One can appreciate that in both embodiments the inserts of the skeleton 5 (i.a. the transparent elements 1) are interlaced with the substantially non-transparent material 3. From other point of view, the skeleton 5 embedded in the material 3 constitutes a spatial lattice structure just as in the previous embodiment.

In the simplest variant of the light transmitting three-dimensional objects 2 according to the second embodiment, a simple layer of the material 3 is situated between two transparent elements 1 being fastened together by means of connecting elements 4.

A third embodiment of the light transmitting three-dimensional object 2 of the invention is shown in figures 6 to 8, being similar to the second embodiment, however, in this case the external layer of the light transmitting three-dimensional object 2 is not constituted by the skeleton 5 but the substantially non-transparent material 3. To this end, further inserts, Le. anchoring elements 7 are fastened to the skeleton 5 in two further layers at the top and the bottom. Said anchoring elements 7 prevents the material 3 from coming off the surfaces of the two external transparent elements 1. The anchoring elements 7 are also joined to the transparent elements 1 by means of connecting elements 4 in this case.

An anchoring element 7 is shown separately in figure 9. The anchoring elements 7 ensure the engagement of the transparent element 1 and the material 3 since the concrete flows between the anchoring elements 7 and the transparent element 1 and, consequently, after its setting it cannot come off the surface of the transparent element 1. In general, the anchoring element 7 should have a further surface part 11 facing the transparent element 1 in addition to the surface 10 ensuring its attachment to the transparent element 1 as this will ensure that it can accept those forces that would detach the material 3 from the

transparent element 1. Evidently, the anchoring elements 7 may be attached to any other inserts, not only to the transparent elements 1.

One can note that the ratio of the surface of the connecting elements 4 situated between the transparent elements 1 to the surface of the transparent elements 1 can vary in a wide range. By using larger connecting elements 4 than the small glass squares shown in the figures, these can increase the light transmitting capacity of the finished light transmitting three-dimensional object 2 on the one hand and can ensure increased mechanical strength for the skeleton 5 and, consequently, for the light transmitting three-dimensional object 2 on the other hand. Glass elements bonded together over large surfaces can ensure excellent mechanical properties for a light transmitting three-dimensional object 2 even without steel reinforcement, hence, it can be used as a lintel.

Mention can be made that the connecting elements 4 can even improve the heat insulation capability of the finished light transmitting three-dimensional object 2, provided that they are hollow, because in this manner a structure similar to cored bricks can be obtained.

In the third embodiment, the connecting elements 4 are situated inside of the light transmitting three-dimensional object 2 in their entirety and are not visible. Therefore, their particular shape, location and material do not affect directly the appearance of the light transmitting three-dimensional object 2. Accordingly, in other embodiments they can be made of e.g. rubber, a plastic material, porcelain, metal, etc. However, the connecting elements 4 indirectly do have an effect on the appearance of the finished light transmitting three-dimensional object 2 as they modify its overall light transmission depending on their transparent or non-transparent material and, furthermore, by increasing the size of transparent connecting elements 4, the light transmitting capacity of the finished light transmitting three-dimensional object 2 can be increased. An interesting effect can be achieved by making the connecting elements 4 embedded in the light transmitting three- dimensional object 2 from e.g. coloured glass, Plexiglas, etc. since they colour the light passing through the light transmitting three-dimensional object 2. In order to achieve the desired effect, the choice of the adhesive materials is also relevant; these can be transparent, coloured or non-transparent. The suitable adhesives include different resins

and ultraviolet-cured adhesives providing rigid bond. One example of the suitable resins is VIAPAL VUP 48 08 B/62, which is a resin being colourless by itself but which can be coloured arbitrarily by means of colorants.

Differently shaped connecting elements 4 can also cause interesting effects similar to that were described above; e.g. the light can be guided into different directions among the transparent elements 1 inside of the light transmitting three-dimensional object 2 by means of connecting elements 4 made from glass prisms of parallelepiped shape.

Lastly, it is to be noted that in the simplest variation of the light transmitting three- dimensional object 2 according to the third embodiment, the skeleton 5 consists of a single transparent element 1 and anchoring elements 7 being attached thereto by means of connecting elements 4.

In another variation of this embodiment (not shown), the connecting elements 4 located between the transparent elements 1, i.e. the glass rectangles has tapered shape and, accordingly, the transparent elements 1 form a fan-shaped pattern on the surface of the of the light transmitting three-dimensional object 2. As a general rule, the shape, the material, the colour and the location of both the connecting elements 4 and the transparent elements 1 can be exceptionally varied, provided that the transparent elements 1 are presented on the surface of the finished light transmitting three- dimensional object 2 in order to ensure its light transmission and that a skeleton 5 maintaining the integrity of the finished light transmitting three-dimensional object 2 is constructed by means of fastening together the inserts embedded in the material 3.

A cross section of a further skeleton 5 that can be used in another embodiment of the invention is shown in figure 10. The transparent elements 1 are rectangular sheet glass plates again, however the connecting elements 4 are glass rods penetrating openings formed in the sheet glass plates. They can also be fastened to each other by adhesive bonding or melting together. In this case, the method for manufacturing the light transmitting three-dimensional object 2 may comprise the step of positioning the skeleton 5 in the mould such that, in addition to the edges of the glass plates, the ends of the

connecting elements 4, i.e. that of the glass rods come into contact with the inside surface of the mould. As a result, it facilitates the positioning of the skeleton 5 on the one hand and the connecting elements 4 being present on the surface of the finished light transmitting three-dimensional object 2 affect the appearance thereof since the light may be transmitted therethrough in one more direction on the other hand. The finished light transmitting three-dimensional object 2 is shown in figure 11.

Obviously, connecting elements 4 of any profile may penetrate the openings formed in the transparent elements 1 and these should not be present on the surface of the light transmitting three-dimensional object 2 necessarily; furthermore, the material of the connecting elements 4 may also be varied in this case, e.g. transparent, coloured as well as non-transparent materials may be used.

Another possible variant of fastening together transparent elements 1 — sheet glass plates, again — by means of the connecting elements 4 is shown in figure 12. In this case, the connecting elements 4 are rings made of one of the materials described above, encircling openings formed in the glass plates. Thus, a channel 6 is formed, extending through the connecting elements 4 and the transparent elements 1, that can be filled with the material

3 when the pouring takes place or even a linking element facilitating the assembly of several superimposed light transmitting three-dimensional objects 2 (not shown) can penetrate this channel 6. Similarly, it can also be envisaged that a further transparent element — a glass rod, a glass bar, etc. — (not shown) is placed in the channel 6.

In this case, the rings can be fastened to the glass plates not only by means of adhesive bonding or melting together but these can also be joined by means of a mechanical fastener, e.g. a bolt with nut (not shown) extending in the channel 6. Another variant of this embodiment is obtained when the connecting elements 4 are constituted by nuts (not shown) arranged on a screw spindle (not shown) penetrating the openings formed on the transparent elements 1. The different joining methods can be varied even within a single light transmitting three-dimensional object 2.

When, in a fifth embodiment of the light transmitting three-dimensional object 2, being similar to the previous ones, the parallel glass rectangles are not arranged parallel to the faces of the light transmitting three-dimensional object 2 but they are arranged at an angle thereto, a wall built from such objects 2 will give life to an interesting light baffling effect. A possible variant of these light transmitting three-dimensional objects 2 is shown in figure 13.

Finally, a sixth embodiment of light transmitting three-dimensional object 2 of the invention is shown in figures 14 to 16. In this embodiment, the skeleton 5 consists of only two transparent elements 1, i.e. rectangular glass frames. These are adhered together to form an arrangement shown in figures 14 and 15 while the finished light transmitting three-dimensional object 2 is shown in figure 16.

An advantage of the method in accordance with the present invention, being compared to the prior art ones, is that it provides substantial freedom concerning the arrangement of the transparent elements 1 within the material 3 and, additionally, it facilitates the efficient mass production of the light transmitting three-dimensional objects 2 because the transparent elements 1 — being fastened to each other — can easily be positioned in the mould. The design of the light transmitting three-dimensional object 2 can be highly diverse and, moreover, by means of the connecting elements 4 linking the transparent elements 1 to each other and being embedded in the material 3 interesting secondary effects can be obtained and the light can be transmitted from any faces or surface parts of the light transmitting three-dimensional object 2 to any other ones through the skeleton 5 consisting of the inserts, as desired. Additionally, while in the known glass-concrete objects substantially "the concrete holds together the glass", in the three-dimensional object 2 of the invention, the transparent elements 1 take at least an equal part in maintaining the integrity of the light transmitting three-dimensional object 2. With such an inner structure, the light transmitting three-dimensional object 2 has not only self- supporting properties but also load-bearing capabilities besides the great light transmitting capacity. Additionally, glass-concrete structures having large-sized surfaces can also be manufactured without using steel reinforcement.

Although the invention has been disclosed by way of describing some particular embodiments thereof, it is not limited to those embodiments, instead, someone skilled in the art is able to effect many modifications and bring about a lot of variants without departing from the scope of the protection defined by the appended claims.