ES2368096T3 - GLASS ELEMENT WITH A CONDUCTING ELECTRICAL STRUCTURE. - Google Patents

Abstract

The invention relates to a glazing member (1) that comprises at least one prestressed glazing (2) having a surface that bears an electric conducting structure (4) connected to electric connection points (5) on the edge of the glazing for connecting the same to the outside, the glazing being connected to a frame-shaped spreading member, that surrounds the field of vision of the glazing member, using a glue bead having a high electric resistance (3A). According to the invention, the conducting structure (4) itself has the shape of a loop or a continuous conducting track, and is provided outside the field of vision of the glazing member (1) substantially or entirely within the surface area covered by the spreading member (3) and the glue bead having a high electric resistance (3A).

Description

Crystal element with a conductive electrical structure.

The invention relates to a glass element that includes a conductive electrical structure with the features of the preamble of claim 1.

In order to form an alarm crystal composed of at least two crystals joined together in an insulating glass by means of a frame-shaped spacer element, it is known, from EP-B1-0058348, to provide on at least one of the crystals a conductive electrical structure in the region of the surface framed by the distance element (field of vision) and prestress that glass. In the assembled state, a sleeping electrical circuit is carried by the electrical structure. It breaks when the glass breaks, which triggers an alarm.

The electrical connection lines of the conductive structure must be led outwards between the distance element and the glass, outside the intermediate space of the insulating glass. In the specific case at hand, they must remain electrically isolated. Likewise, the tightness of the intermediate space between the crystals of the insulating glass should not be compromised. In the aforementioned document, the segment of the conductive structure covered by the spacer element is electrically isolated with the help of a non-conductive cooked screen printing paste.

Document DE-C1-19960450 discloses, from the aforementioned solution, an isolation of the line segments located below the spacer element with the contest of a plastic layer, which can be, for example, a thin film , joined by complementarity of force or matter to the surface of the glass after prestressing. In a preferred embodiment, the thin insulating film determines at the same time a support film for joints manufactured from a flat conductor.

From DE-C1-10154558, such a crystal element is known, based on this state of the art. At this point, to insulate the conductive structure in relation to the glued spacer element, at least in the crossing region along a predetermined length, a tail cord of a material having a clearly increased electrical insulation effect is used regarding the matter of the rest of the tail cord. Also in this solution, the conductive structure is, however, arranged inside the field of vision, analogously to the solution of DE-C1-19960450 and, therefore, remains visible.

Document DE-A1-4011541 discloses a prestressed alarm glass with a conductive electrical coating. With the help of a separation line marked by a laser beam, a marginal band of the electrical heating lining is electrically separated from the main region of the lining and a "conductive structure" is also formed. in the sense of the aforementioned publications. The aforementioned partial region is used, with the contest of separate external contacts, as a sensor to detect a rupture of the prestressed glass in question. This can be incorporated in a composite glass or also in an insulating glass element, in the latter case admitting that the partial region of the sensor-based coating is located outside the part of the face framed by the distance element of the insulating glass , in order to avoid known isolation problems. Preferably, a layer system is used, which can withstand a strong thermal load and which can already be deposited on the surface of the glass before prestressing.

Document DE-A1-10358316 finally describes an insulating glazing alarm glass, whose spacer element is located at a certain distance from the outer edge of the prestressed alarm glass itself and thus leaves a free edge zone, in the that the conductive loop is provided to trigger an alarm in case of glass breakage. With this solution, the risk of a disturbance of the operation due to the bonded composite edge and, specifically, as a result of a possible short circuit of the conductive loop with the metal spacer or metal container element must be avoided. With this solution, there is, however, a certain risk of malfunction due to moisture penetrating from the outside, against which a sufficient tightness for the conductive loop cannot be reliably ensured.

Since, in the past, with such crystals, untimely alarms have occurred repeatedly, the requirements in terms of insulation quality (insulation values or insulation resistance) increase for those electrical joints, which are controlled by their resistance to breakage. dielectric with test voltages ranging up to 1000 V. Against this background, the glues used to date for the distance frame in the insulating glazing elements, namely butyl cords generally colored black with soot for optical reasons, they do not have sufficiently high insulation values and contribute little to the quality of the insulation. Precisely in the region of the junction of the joints and the spacer element, the tail cord is brought to a thickness of a few tenths of a millimeter in the pressing of the composite material, so that very high values of electrical insulation are needed at that site.

In the case of use, the insulation resistance can also have a strong influence of moisture or water. This concerns especially matters of secondary sealing located outside because of their relatively large surfaces.

It is true that the mass of the glue could be colored with other coloring substances, but a transformation of the mass production or a separate manufacture of smaller quantities with other coloring substances would lead to a high expense, which the manufacturers of glues reject and whose costs Totals are not accepted by customers.

Document CA920683A1 describes a glazing comprising a first sheet of tempered glass, a second sheet of glass and a spacer that extends between the two sheets of glass along its contour. The glazing also comprises an electrically conductive layer, connected to an alarm and fixed to an inner edge surface of the tempered glass sheet. A layer of glue is deposited between the spacer and the inner edge surface of the glass sheets.

The purpose of the invention is to provide a glass element that is still visually improved without violating the safety of operation.

This purpose is achieved, in accordance with the invention, by the features of claim 1. The features of the secondary claims have advantageous embodiments of this invention.

For the benefit of a coating as limited as possible between the spacer element or its tail and the conductive structure, on the one hand, to avoid useless contact possibilities and, on the other hand, to ensure as good as possible adhesion of the glue on the surface of the glass, to date, the essential crossings or connecting segments of the conductive structure have been made in a cross-over zone of limited expansion below the distance element.

Because, according to the invention, the conductive structure or the alarm loop itself is arranged outside the field of vision of the glass element, essentially or completely (leaving out the necessary external connections) in the area of the surface covered by The spacer element and by a tail cord of high electrical resistance - preferably using, in a manner known per se, a special material - renounces a precautionary measure generally applied to date with regard to insulation ratios between the conductive structure and the distance element and, at the same time, this conductive structure is completely concealed. By comparison with the solution of DE-A1-10358316, however, the protection of the conductive structure against moisture that causes corrosion and short circuits is preserved at a high level.

The conductive structure or the alarm loop itself can be re-deposited in a single operation by screen printing on coated or uncoated glass.

It is true that, in general, it is intended to provide the connection contacts of the two ends of the conductive structure close to each other, however, it is also possible to distance them from each other (as shown in documents DE-A1- 10358316 or DE-A1-4011541). Then the conductive structure can also be designed as a rectilinear conductive path as a whole (possibly by means of sinuous or wavy or zigzag shaped segments), which, as a whole, runs parallel to and below the respective segment of the spacer element throughout length - setting aside the outer connection regions or alloy welding points. The connection points are not part of the conductive structure in the strict sense.

To ensure a sufficient distance between the distance element and the conductive structure, even in case of excessive pressing of the tail bead, it is possible to deposit on the surface of the glass, in addition to the conductive structure, projections or pythons that rise above of the surface of the glass higher than the conductive structure itself.

A conductive structure produced by screen printing in a continuous industrial process rises from 10 to 50 µm above the surface of the substrate or glass.

In the interest of safety, the thickness of the glue layer should not be less than 200 μm. The height or the necessary prominence of the pythons mentioned for the distance element is derived without difficulty. These pythons can also be made, if necessary, by screen printing or also by deposition / gluing of other materials on the surface of the glass close to the conductive structure. They can also be carried out analogously to the solution already mentioned according to DE-C1-19960450, in the form of flat plastic pieces and also covering the conductive structure, partially or in some places. In the specific case at hand, it is naturally not necessary to settle the spacer element by completely crushing the tail material effectively on the pythons locally, but it can also remain in its region between the pythons and the spacer element.

To further increase the insulation safety, another insulating material can be inserted between the spacer element and the conductive structure, preferably between the latter and the glue material, until this does not compromise the safe tightness of the space between the crystals because from the tail.

Tests have shown that the conductive structure also breaks with the rupture of the prestressed glass,

regardless of whether it is, according to the invention, in an area of the surface of the glass, which in principle is supported by a layer of elastic glue and the distance element. However, unquestionably, however, several cracks in the longitudinal layout of the conductive structure are formed with the breakage of the crystal, since it is longer than the average size of the fragments formed with the breakage of the prestressed glass. Consequently, current can no longer circulate through the conductive structure, so that its function as a sensor (sleeping electric) for glass breakage is preserved. At the same time, the demand for an insulation resistance of at least 10 MO can be satisfied.

Other details and advantages of the object of the invention will be revealed by means of the drawings of an embodiment of the invention and by its subsequent detailed description.

In these drawings, which are simplified representations without particular scale,

Fig. 1 represents a first embodiment of a glass element according to the invention with a conductive structure;

Fig. 2 represents a second embodiment of the conductive structure;

Fig. 3 represents a third embodiment of the conductive structure;

Fig. 4 is a partial sectional view of the glass element along line IV-IV of Figure 1, in the region of a connection point for an outer joint of the conductive structure;

Fig. 5 is a partial sectional view of the glass element along the line V-V of Figure 2, seen in the direction of the overall longitudinal dimension of the conductive structure; Y

Fig. 6 is another partial sectional view of the glass element, seen transversely to the overall longitudinal dimension of the conductive structure.

According to Figure 1, a glass element 1 comprises a prestressed glass 2 as well as a distance element 3, which, in Figures 1 to 3, is only indicated by dashed lines in its parallel path to the outer edges. of the glass 2. The spacer element 3 links the glass 2, with the contest of tail cords, usually to another glass or plastic window panel, in an insulating glass (see Figures 4 and 5). This also frames the field of vision of the finished glass, which is normally used as a building window or integrated into it. The spacer element 3 itself is composed, in large lines, of a hollow profile filled with a drying agent. This profile can be made of metal (for example, aluminum) or plastic.

On the surface of the crystal 2 directed towards the spacer element 3, a conductive structure 4 has been applied by screen printing or otherwise fixed (for example, by inkjet printing, extrusion) durably in place on the surface. The essential part or all of that conductive structure is located inside the surface covered by the spacer element 3, therefore outside the field of view of the window pane. Two connection points 5 (alloy welding points) of the conductive structure are provided, at the two ends of the latter, outside the region of the surface or the field of vision framed by the spacer element 3. These points of connection 5 is still accessible after the fabrication of the composite insulating window material, that is, after the gluing of the spacer element 3. They are welded with external material (cables) 6.

Figure 2 shows a variant of the conductive structure, in which the two connection points 5 are located on either side of the ends of the part of the distance element that covers the conductive structure 4. This allows extended support of all the conductive structure and a great total length.

Figure 3 shows another variant of the conductive structure, in which the two connection points 5 are in an angle region of the crystal 2. The conductive structure describes at this point, in the region covered by the spacer element 3, a loop in which two segments of this conductor loop are parallel to each other, both in the region of the surface covered by the distance element.

In the three embodiments, the overall longitudinal extension or the longitudinal direction of the conductive structure 4 is parallel to the layout of the spacer element 3. Locally, this can be, as already mentioned and as represented at this point, in shape of zigzag or rectilinear, in the form of a loop, or also present any shape that moves away from the straight line (undulations, meanders). A general demand is only that it does not leave the region covered by the spacer element 3 or by its gluing, and that its length is greater than the size of the (relatively small) fragments produced with the rupture of the prestressed glass. It is also possible, in view of increased safety against moisture that penetrates from the outside, to settle the entire layout of the conductive structure 4 under the spacer element, with an off-center trend in the direction of the field of vision.

If the conductive structure should not be arranged under a segment of the distance element with a path

non-rectilinear, for example curved or angled, its overall longitudinal extension would naturally adapt accordingly.

Typically, a certain distance between the spacer element and its glue and the outer edge of the glass, or an overflow of the surface of the glass beyond the surface covered by the spacer element is provided. On the one hand, this allows the residual edge groove to be filled with another sealing agent (preferably polysulfide). On the other hand, in the region of the conductive structure 4, there is sufficient room for the electrical connection of the connection points 5 of the conductive structure 4 taken outside the space framed by the distance element, in a place hidden from view.

Often, this edge region as well as the contact regions of the glue cords with the glass are still hidden from view by means of an opaque flat impression (which for simplicity is not shown at this point), which is located below the joints, directly on the surface of the glass. This printing can also be done by screen printing and cooking. This can also serve as a basis for an adhesion agent that will eventually be applied ("primary") for gluing the distance element.

In the absence of the aforementioned opaque impression, the observer could recognize the views of Figures 1 to 3, particularly of the conductive structures 4, even looking at the outer side of the glass element.

Preferably, the entire conductive structure 4, in addition to the connection lines and connection points 5 (alloy welding points), is deposited by screen printing of a baking paste, ceramic, of a material for welding with input material with a large content of silver (more than 80% silver) in a thickness of approximately 0.01 to 0.03 or also up to 0.05 millimeters and in a width between 0.25 and 1 millimeter. This paste is cooked by heating at high temperature necessary for the thermal prestressing of the glass 2. The electrical conductivity is fully sufficient for the described application cases, even with such small cross sections.

Of course, other techniques other than screen printing can also be applied to produce the conductive structure on the glass surface, for example inkjet printing or extrusion.

Figure 4 shows a partial section, enlarged to make it clearer, through the edge of the glass element 1, observing in the overall longitudinal direction of the conductive structure 4. This is only visible from one section face. It is well seen at this point that the conductive structure 4 is deposited directly on the surface of the glass 2, so that it is also destroyed with certainty in case of breakage of this crystal and thus interrupt the sleeping electrical circuit applied. It is also seen that a tail layer / a tail cord 3A for joining the distance element 3 completely covers the conductive structure 4 which is under the distance element 3, so that the latter does not have any contact with the outside, towards the intermediate space between the crystals and towards the distance element 3.

Finally, for the implementation of the present invention, it is of interest that the conductive structure 4 is covered by the tail cord 3A. Unlike the representation, the latter can also be slightly wider than the spacer element 3 itself; this greater width can be adjusted, for example, by laterally displacing the glue material in the pressing of the spacer element.

It cannot be accepted that the link between the glass 2 and the tail bead 3A is compromised by the conductive structure. The latter is composed, in a known manner, of a vitreous material (glass frit with the addition of silver), such that between it and the glue material the same adhesion conditions prevail as between the surface of the glass and the matter of tail. By cooking, the conductive structure also adheres very strongly to the surface of the glass.

Only a short segment of the conductive structure 4 comes out, as a link with the connection point 5, of the coating with the spacer element 3 or with the tail cord 3A. As already mentioned, the edge groove between the spacer element 3 and the outer overhang of the glass 2 is filled with a mass of additional sealing 7. It also covers the connection point 5 with an outer joint welded with input material 6 and insulates its connection region outwards.

Figure 5 shows another partial section corresponding to the line V-V of Figure 2, therefore also observing in the overall longitudinal direction of the conductive structure 4 in the region covered by the spacer element 3 and the tail bead 3A.

The extension of the sealing mass 7 upwards and, beyond that, a second window plate 2 ’, with which the glass element 1 determines a multiple crystal, has been indicated schematically in Figures 4 and 5

or a complete insulating glass.

The layers or the cords of glue on the two faces should be deposited before the union of the two window plates, with the contest of the spacer element 3 in the form of a frame, with a thickness as uniform as possible. Those can be deposited, either directly on the glass surfaces along their region of

contact with the distance element, or (preferably) on the distance element itself.

In most cases, the tail cords 3A are made of butyl rubber, which adheres notably and durably to both glass surfaces and metal surfaces, and which can be deposited by extrusion in the form of a bead or interrupted molding on the surface of interest of a piece.

With the pressing of the crystals 2 and 2 ’with the spacer element 3 in a conventional manner, the tail cord 3A is strongly compressed. In the specific case at hand, the matter located under the spacer element 3 could also escape laterally to the outside and there may no longer be a sufficient layer thickness for insulation with a conventional glue. To minimize the risks, at least the entire region of the coating is glued between the spacer element 3 and the conductive structure 4 with a highly insulating glue in accordance with DE-C1-10154558.

When the conductive structure has an extended shape, such as that shown at this point (which does not, therefore, form a conductive loop in its own direction), short circuits "internal" can certainly not be accepted by nature. of the conductive structure, which could lead to the untimely firing of an alarm with an evaluation electronics whose sensitivity is adjusted accordingly. However, great importance is attached to quality insulation.

Regardless of this, of course, the conductive structure can also be made, in the present case, as shown in Figure 3, in the form of a conductive loop with connection points 5 immediately next to each other, without abandoning the construction principle according to the invention.

If you want to glue the spacer element 3 only in the region of the conductive structure 4 with the glue that has very high values of electrical insulation, obviously the latter must be compatible with the material of the tail cord "normal". Precisely in transitions, the tightness of the finished tail bead must be preserved against the penetration of gases and moisture in the composite glazing. This can be considered as the realization of transitions without joints between most of the tail cord and the segment (s) used, as needed, in the crossing region. Naturally, a heterogeneity persists in the transitions even after the crushing of the tail cord, which can be visible with careful examination, even if the two subjects have the same coloration. However, in no way can this reduce the tightness.

For example, in the simplest case, a butyl material without soot, either colorless or colored with other coloring substances (non-conductive) can be used for high quality insulation. In this way, but also with other comparable tails, a good homogeneity can be obtained in the transitions with the peripheral tail bead on either side of said region.

This expense, in total slightly increased in relation to the usual fabrications to date, is only necessary on the side of the distance element that is oriented towards the prestressed glass provided with the conductive structure. The distance element can be attached to the other glass in the usual confirmed manner, with a peripheral tail bead, which must not have particular electrical insulating properties.

A supplementary (secondary) sealing mass is then deposited, for example of Thiokol, polysulfide, silicone or polyurethane, externally around the distance element and the adhesive layers, in order to ensure a supplementary sealing of the intermediate space between the crystals and also to seal the connection faces located outside. The electrical insulation properties of this sealing mass are certainly analogous to those of the glue itself, although this supplementary sealing material retains a relatively large thickness everywhere, so that at this point the problem of failure cannot occur of electrical insulation of an extraordinarily small layer thickness.

Figure 6 finally shows another partial section considered transversely to the overall longitudinal extension of the conductive structure 4 (in an embodiment analogous to Figure 1). At this point two pythons 3S are seen arranged on either side of the conductive structure 4, which preferably are also fully embedded in the tail cord 3A. It should be remembered that the conductive structure rises a maximum of 50 m above the surface of the glass 2 and that, consequently, the 3S pythons only need a very short height of approximately 2 tenths of a millimeter. These can either be formed by screen printing themselves, or, where appropriate, be made up of small pieces of a non-conductive (plastic) material, which can be glued on the face of the glass.

Figure 6 shows that there can still be a thin layer of glue between the 3S pythons and the spacer element 3. Only in an extreme case, the two 3S pythons would support, in the manner of a bridge, the segment that covers the structure conductive, so that they avoid any contact between the conductive structure and that segment and also preserve between them a layer of insulating tail thick enough.

Unlike this representation, these pythons 3S (which also ensure the function of the spacer element), of course, can also be placed above the conductive structure 4, substantially like the insulating layer described in DE-C1-19960450 , which, contrary to that, would not require concealment over the entire length of the coating. This would be especially recommended in an embodiment of the conductive structure according to Figure 2, but would be equivalent, from a functional point of view, to the solution illustrated at this point in Figure 6.

Claims (14)

1. Glass element (1) comprising at least one prestressed glass (2) whose surface carries a conductive electrical structure (4), which is connected to electrical connection points (5) on the edge of the glass (2) with you look at its outward connection, in which

•

the glass (2) is provided as a component of a multiple window or insulating element formed by at least one other glass (2 ’) and a distance element in the form of a frame, which surrounds the field of vision of the glass element,

•

the spacer element (3) attached to the surface of the glass (2) carrying the conductive structure (4) by means of a tail cord (3A) covers at least some parts of the conductive structure (4), the own being arranged conductive structure (4) outside the field of vision of the glass element (1) essentially or completely in the region of the surface covered by the distance element (3) and the high electrical resistance tail cord (3A), characterized in that The tail is of high electrical resistance and because, between the distance element (3) and the surface of the glass (2), in the region of the conductive structure (4), pythons (3S) that limit the approach of the element are provided spacer (3) in the pressing of the glue layer (3A), the pythons (3S) being arranged next to the conductive structure (4).

2.

Glass element according to claim 1, characterized in that the conductive structure (4) runs as a whole parallel to the layout of the distance element (3).

3.

Glass element according to claim 1 or 2, characterized in that the conductive structure (4) is made in the form of a continuous conductive path as a whole with two connection points (5) arranged at its ends with a distance corresponding to the length of the conductive path or in the form of a loop with connection points located close to each other.

Four.

Crystal element according to any one of the preceding claims, characterized in that the conductive structure (4) has at least in segments a wavy, zigzag, winding or otherwise moving away from its overall longitudinal extent.

5.

Glass element according to any one of the preceding claims, characterized in that the total insulation between the conductive structure (4) and the distance element (3) has an electrical resistance of at least 10 MO.

6.

Glass element according to any one of the preceding claims, characterized in that it is provided, between the conductive structure (4) and the distance element (3), particularly between the conductive structure (4) and the tail bead (3A), at least another thin insulating layer of a non-conductive material of electricity, for example polyimide or polyethylene.

7.

Glass element according to any one of the preceding claims, characterized in that the segment of the high electrical resistance tail cord (3A) located in the coating region is extruded in the same place between the ends of a tail cord of another material, that connects to it.

8.

Crystal element according to any one of the preceding claims, characterized in that at least the segment of the tail cord (3A) located in the coating region is composed of butyl rubber without soot.

9.

Glass element according to any one of the preceding claims, characterized in that its conductive structure (4) is produced by screen printing, inkjet printing or extrusion of a corresponding paste, electrically conductive, on the surface of the glass.

10.

Glass element according to any one of the preceding claims, characterized in that the conductive structure (4) is cooked by a heat treatment, particularly on the occasion of the thermal prestressing of the glass (2).

eleven.

Glass element according to any one of the preceding claims, characterized in that the conductive structure (4) is provided with connection points (5) located outside the surface of the glass framed by the distance element (3).

12.

Glass element according to claim 11, characterized in that the connection points (5) are formed with the conductive structure (4) in a single operation.

13.

Glass element according to any one of the preceding claims, characterized in that another sealing mass (secondary) (7) covers the outwardly directed face of the distance element (3) peripherally around the glass element (1).

14.

Crystal element according to any one of the preceding claims, characterized in that the

glass (2) and the distance element (3) are connected to another window plate (2 ’) in a multi-window or insulating window.