WO2011076166A1

WO2011076166A1 - Method and device for producing insulating glass

Info

Publication number: WO2011076166A1
Application number: PCT/DE2010/001424
Authority: WO
Inventors: Johan Pieter Hofmann; Francisco Lopez Lopez; Dieter Schäufler
Original assignee: Elino Industrie-Ofenbau Gmbh
Priority date: 2009-12-22
Filing date: 2010-12-07
Publication date: 2011-06-30
Also published as: EP2516783B1; EP2516783A1; DE102010045616A1

Abstract

The invention relates to a method and device for producing insulating glass. In the method, two glass panes are connected to each other by means of a glass frit applied to the first and/or second glass pane in the form of a border, wherein a frame-shaped spacer can be used. The interior of the insulating glass unit formed is evacuated by means of natural clearances between the glass panes in the area of the glass frit border, wherein said natural clearances can be formed by natural gaps and/or pores in the glass frit or the natural gap formed between the glass frit and the glass panes. Optionally, the remaining exhaust gases in the interior can be pumped out by means of a special venting opening in a subsequent second evacuation step. The device suitable for performing said method is a furnace system having a plurality of chambers arranged one behind the other.

Description

Method and device for producing insulating glass

The present invention relates to a method for producing insulating glass. The invention further relates to an apparatus for carrying out such a method.

Known insulating glass panes consist of two insulating glass panes connected via a frame, wherein the interior space between the two panes is filled with a gas mixture. In order to increase the thermal insulation value of such insulating glass panes, such discs are produced in recent times without gas filling. In this case, a negative pressure is generated in the interior between the two glass panes. In this case, a negative pressure of 10 ^"1 to 10 ^{" 7} mbar is sought.

For the production of such insulating glass panes or insulating glass units, it is known to arrange a slotted metal frame between the panes. Through the slots of the metal frame, the interior is evacuated between the panes, after which the metal frame with the glass sheets is glued over a suitable plastic adhesive. In another known method, the interior space is evacuated between the two glass panes, whereafter two metal strips arranged in the end areas of the panes are welded together in order to seal off the interior space. The welded together, protruding metal strips are then crimped.

In the method mentioned in the first place, there is the problem that the plastic adhesive used ages and embrittles, so that there is a risk that the evacuated gap between the glass sheets will air over time. In the second known method, in which corresponding metal strips are used for sealing, there is the problem that as a result of the use of different materials, different thermal expansion coefficients are present, which result in different expansions of the materials and can thus cause damage.

The present invention has for its object to provide a method and apparatus for the production of insulating glass, which or the production of particularly dense and aging-resistant insulating glass with a particularly high vacuum (vacuum) allows.

This object is achieved according to the invention by a method comprising the following steps: a. Providing a first glass sheet and a second glass sheet; b. Applying a glass frit in the form of a border on the first and / or second glass sheet; c. Placing the glass panes with the border between them to form an insulating glass unit;

Evacuation of the interior space between the glass panes via natural clearances located in the area of the border between the glass panes and heat treatment of the insulating glass unit to soften the glass frit and gluing the glass panes and e. Allow to cool after sealing the insulating glass unit tightly.

In the method according to the invention, a glass frit (solder glass) is used to connect the glass sheets as the bonding medium. This has the advantage that glass discs ben and connecting medium made of the same or a similar loan material and have the same or similar coefficients of thermal expansion, so that the risk of different sizes of material expansions or Materialkon traktionen is turned off. The glass frit is applied in the plastic state, preferably in the form of a strip-shaped border, wherein the border can be applied in a targeted manner, that the height thereof in particular natural way is different, preferably wave-shaped. For the implementation of the method according to the invention, however, the formation of the outline in waveform to obtain a natural gap between the border and glass is not necessarily required. It is essential that, even after the application of the glass frit, there are natural free spaces in the region of the surrounding area which make it possible to evacuate the interior space. These natural free spaces can also be formed, for example, by pores, gaps and other cavities within the glass frit. Such natural free spaces can be generated or promoted by an irregular application of the glass frit.

The glass frit is dried after application to an acceptable hardness. After stacking the glass panes provided with the border, natural clearances or a natural gap are thus present between the glass panes. In this state, d. H. Pre-stage, therefore, the assembled insulating glass unit is still open to the surrounding atmosphere. The glass panes can then be mechanically fixed to one another (with the border arranged therebetween from the glass frit), so that lateral displacements are no longer possible.

For example, appropriate clamping devices can be used for fixing. Another possibility is to achieve fixation via weight loading. Other measures are also possible.

In a next step, the interior space between the panes of glass is then positioned over the area around the border. natural evacuation, in particular over the natural gap formed with the applied glass frit, evacuated to produce a desired negative pressure (vacuum), for example between 1CT ¹ to 10 ^"7 mbar .. The execution of the evacuation of the natural free spaces, especially the formed natural gap, has the advantage that the interior can be pumped out much faster than is the case, for example, when evacuating through a special hole in the glass pane.Aluminatively evacuated or staggered to this takes place a heat treatment of the insulating glass unit to the applied glass frit The heat treatment is carried out until a tight connection between the glass panes is achieved, after which the insulating glass unit is allowed to cool gradually, so that the glass frit can solidify.

When carrying out the heat treatment for softening the glass frit, corresponding exhaust gases can form which, as long as the natural free spaces or the natural gap are still open, are pumped out via these free spaces or this gap. It is understood that such exhaust gases are undesirable in the interior of the unit, since a gas-free space as possible should be generated here. As a rule, such exhaust gases can be evacuated or pumped out via the natural free spaces in the border. However, if the glass frit has softened so much that the initial natural gap has disappeared, it may happen that the residual exhaust gases remaining in the interior are no longer removed via the gap. In spite of To allow such a distance, preferably carried out after the dense bonding of the insulating glass unit further evacuation of the interior space via at least one additional vent hole. About this vent hole therefore existing in the interior due to the melting of the glass frit exhaust gases are removed from this until the final stage of the desired negative pressure or vacuum is reached. After completing the further evacuation process, the intended vent hole is closed. Thereafter, the insulating glass unit is cooled.

In the method according to the invention, therefore, a two-stage evacuation process preferably takes place. The first evacuation step, i. H. the main part of the evacuation is carried out over the natural open spaces formed with the border. This is followed by a second evacuation step, preferably at a lower temperature, to remove the residual exhaust gases from the interior of the unit, which is passed through the venting hole provided.

The inventive use of a glass frit makes it possible to achieve a particularly tight connection of the glass panes (possibly with the interposition of a frame-shaped spacer). The use of a glass frit has the further advantage already mentioned that hereby the connection medium has almost the same coefficient of thermal expansion as the glass panes or the spacers used. Finally, a glass frit as a connecting medium has little aging problems. In order to prevent the disks from pulling against each other when evacuating the intermediate space between the glass panes, additional spacers are preferably provided in the interior at corresponding intervals distributed over the panes. These spacers are made of glass or similar transparent components so that they are poorly visible to the naked eye. They are glued to the glass panes, for example thermally or with UV-reactive plastics.

Preferably, in the method according to the invention, the closing of the vent hole is carried out at a temperature lower than the heat treatment step. This ensures that the glass frit used for bonding the glass panes emits no further exhaust gases at this stage, so as to ensure that the vent hole and thus the insulating glass unit is finally closed, without any exhaust fumes are still in the interior.

For carrying out the method, it is expedient to use a glass pane provided with an open vent hole or a corresponding frame-shaped spacer. This vent hole is open from the start and will not close until the end of the process. The closing takes place, as mentioned above, after the further evacuation of the interior. All process steps can therefore follow one another directly.

In another variant of the method according to the invention, to carry out the same one with a closed a vent hole provided glass plate or a corresponding frame-shaped spacer used, wherein the vent hole is opened before further evacuation. In this process variant can therefore between the

Main process of evacuation over the natural free spaces and the subsequent further evacuation via the vent hole quite a process interruption take place, since the insulating glass unit is already glued with the help of glass frit and the vent hole is closed. However, there are still exhaust fumes in the interior. The vent hole can then - be opened at a later date - and the remaining exhaust gases can be pumped, after which the vent hole is closed. In this variant of the method, therefore, the vent hole must be closed, opened and then finally closed again, so that more process steps are required than in the method variant described first, which is operated from the beginning with an open vent hole.

The vent hole is conveniently closed by melting and fusing a serving for sealing substance. The substance is melted by appropriate heat and melts it to the edges of the vent. The sealing substance used is preferably glass material or glass frit material, ie those materials which are used anyway for the insulating glass (preferably no foreign materials). Also suitable metals or plastics may be used. In a variant of the method, the substance used for sealing is fixed in the area of the vent hole during the execution of the method. For fixing purposes, for example, glass tubes or other glass elements may be used. The fixation prevents the substance from leaving the area of the vent opening.

Preferably, the occlusive substance is fused and fused by laser action, inductive or microwave energy. For example, a laser beam is aimed at the substance, which may be, for example, a glass bead, whereby the glass bead is melted and thus the vent opening is closed. In the substance, a magnetically conductive metal may be mixed, so that a melting can be carried out, for example, in an inductive manner. Also, a melting can be achieved by means of microwave energy. The two last-mentioned methods have the advantage that the energy required for melting does not have to be applied specifically to the substance, as is the case with a laser beam. Of course, other methods for closing the vents are possible, in particular the use of other heat sources.

Preferably, a glass sheet or spacer with a vent hole located in a corner area is made to be worn. The additional ventilation hole may also be provided in the border formed by the glass frit. This can be realized for example by means of a pipe.

It is understood that in general also several additional vent holes can be provided. From the manufacturing effort, however, their number should be as low as possible

The frame-shaped spacer is preferably a glass frame. However, it can also find a metal frame use.

In the method according to the invention therefore finds a glass frit as a connecting medium between the two glass ben and ben if necessary, the spacer (glass frame) use. The evacuation of the interior is preferably carried out in a two-step process, being evacuated in a first step on the natural clearances between glass frit and glass or glass frit and spacer. In a second step, the remaining exhaust gases, which are still present in the interior after bonding the discs together or with the spacer, evacuated via a specially provided vent hole (pump hole). Thereafter, the pump hole is closed.

Of course, in the method according to the invention more than two glass panes can be used, wherein two glass panes each between them have a spacer Tönnen. The above object is further achieved by an apparatus for producing insulating glass. The device is designed as a furnace system provided with a transport device for the insulating glass panes with a multiplicity of heating and cooling chambers arranged one behind the other and separated from one another, wherein at least some of the heating and cooling chambers are provided with negative pressure generating devices. At least one heating chamber may have a closing device for the vent hole. Between various heating and cooling chambers separating devices are provided, which ensure a separation of the maintained in the respective chambers atmospheres. With the aid of the transport device, the insulating glass units to be produced are conveyed through the individual chambers of the furnace installation, where they are heated, evacuated and / or cooled in the chambers. Such a furnace plant is constructed, for example, as follows:

It has a loading device with which the insulating glass units are successively introduced into a preheating chamber. This is followed by another preheat chamber. Via a vacuum gate, the units are introduced into a pre-vacuum / heating chamber, pass through this chamber and enter a further heating chamber, in which the actual bonding process takes place. From this heating chamber, the units in turn pass through a vacuum gate into a chamber in which a pre-high vacuum is generated. Next are two high-vacuum chambers, which are also separated by corresponding vacuum gates. Then follows a chamber, which is provided with a vent hole closing device and in which closed the vent hole becomes (at a slightly lowered temperature). Finally, a pre-cooling chamber and a subsequent cooling chamber follow. With a discharger the finished insulating glass units are removed from the furnace. Such a furnace system can be designed as a straight-ahead version, but also in angled, circular or U-shaped form.

The subsequent pumping of the residual gases at the cold Iso lierglaseinheit can also be done outside the furnace, in particular special pump stems.

The invention will be described below with reference to a Ausführungsbe game in connection with the drawing in detail erläu. Show it:

1 shows a partial vertical section through a Isoliergla unit before the heat treatment;

Figure 2 is a partial vertical section through the Isoliergl

Unit after heat treatment;

Figure 3 is a plan view of an insulating glass pane;

FIG. 4 shows partial vertical sections through three insulating glass units with possible alternatives for closing the venting hole (pumping hole);

Figure 5 is a schematic representation of a furnace system for carrying out the method for producing insulating glass units; and FIG. 6 shows a temperature / pressure / time diagram for the furnace installation of FIG. 5.

FIG. 1 shows a partial vertical section through an insulating glass unit before the heat treatment. One recognizes a first (upper) glass sheet 1 and a second (lower) glass plate 2, ^"between which a suitable spacer 3 is arranged in the form of a glass frame. For bonding the glass sheets 1, 2 with the spacer 3 is used, a suitable glass frit (solder glass ) which is applied in the form of a border to the underside of the first glass pane 1 and to the upper side of the second glass pane 2. The corresponding glass frit borders are designated 4 and 6. The glass frit is applied so that its application height varies, so that in each case After the individual parts have been placed on top of each other, a natural gap 5 is formed between the glass frit and the spacer 3, via which the interior of the insulating glass unit communicates with the surrounding atmosphere in order to prevent the parts of the unit from moving , these are about a suitable one

Clamping device 7 mechanically fixed together. A fixation can also be done for example via a suitable weight load.

The insulating glass unit of Figure 1 is conveyed through a suitable furnace, as described later. By the corresponding heat treatment, the glass frit border 4, 6 is melted, so that both glass panes 1, 2 are glued in a sealed manner with the spacer 3. fi Figure 2 shows the insulating glass unit after the heat treatment has been carried out.

FIG. 3 shows a plan view of the insulating glass unit of FIGS. 1 and 2. In the lower right corner in FIG. 3, the upper glass pane 1 is provided with a small vent hole (pumping hole) 8, which serves to evacuate residual exhaust gases from the interior of the insulating glass unit, after the main part of the exhaust gases has already been pumped off via the natural gap 5 shown in FIG. After evacuation of the remaining exhaust gases, the vent opening 8 is closed, wherein Figure 4 shows five alternatives for closing. In the first upper illustration, the closure takes place with the aid of a glass bead 9, which is melted by means of a laser beam, whereby the opening 8 is closed. In the second illustration, the closure via a plug 10 made of a refractory glass frit. The frit may contain possible metal admixtures, so that the vent hole can be closed in an inductive manner by melting the plug. In the third illustration, a glass stopper 11 is used, which is fixed by a glass tube 12. This glass tube 12 prevents the glass stopper from being removed from the area of the vent during treatment. The melting can be done here, for example, by applying microwave energy. In the fourth illustration, the upper glass pane is provided with a pumping stem 30 made of glass, which is sealed for sealing. In the fifth illustration, the pumping stem 30 is arranged on the spacer 3. Figure 5 shows schematically a longitudinal section through a ge suitable furnace for the production of insulating glass. At the left end of Figure 5 is a loading device 21, introduced with the insulating glass units in the state of Figure 1 successively in the furnace and there on a suitable transport device (not shown) are arranged. The furnace 20 has a plurality of chambers 24, 25, 26 and 27, which are partially separated from each other via suitable At mosphären separating means 23, which are each formed as a vacuum gate, to prevent mixing of the individual atmospheres. Introduced into the furnace insulating glass units pass first two preheating 24 and then pass through a vacuum gate in a pre-vacuum / heating chamber. This is followed by an adhesive / heating chamber, pre-high vacuum chamber, high vacuum chamber and high vacuum chamber, which are separated from each other by vacuum gates. In these chambers, the bonding of the unit and the main process for evacuating the interior takes place. The unit then passes into a chamber 26 which is provided with a closing device for the vent hole 8 Ent. In this chamber, a somewhat lower temperature than in the previous chambers is maintained in order to prevent further outgassing of the glass frit. After the closing of the vent hole in the chamber 26, the insulating glass units pass through a pre-cooling chamber and a cooling chamber 27 to an unloading device 22, with which they are guided out of the furnace 20.

FIG. 6 shows a temperature / pressure / time diagram of the furnace installation shown in FIG. With the solid line never the respective chamber temperature is shown. The dashed line shows the respective chamber pressure. After the insulating glass units have passed through the furnace, they have in their interior a negative pressure of up to 10 ^{~ 7} mbar.

Claims

claims

1. Method for producing insulating glass with the following steps: a. Providing a first glass sheet and a second glass sheet; b. Applying a glass frit in the form of a border on the first and / or second glass sheet; c. Placing the glass panes with the border between them to form an insulating glass unit; d. Evacuation of the interior space between the glass panes via natural clearances located between the glass panes in the area of the border and heat treatment of the insulating glass unit to soften the glass frit and

Gluing the glass panes; and e. Allow to cool after sealing the insulating glass unit tightly.

2. The method according to claim 1, characterized in that according to step c. superimposed glass sheets are mechanically fixed together.

A method according to claim 1 or 2, characterized in that the applied border is applied at different heights, so that there is a natural gap between the stacked glass sheets.

Method according to one of the preceding claims, characterized in that after the dense bonding of the insulating glass unit, the interior thereof further eva kuiert at least one additional vent hole, which is then closed.

Method according to one of the preceding claims, characterized in that spacers are provided between the glass sheets, which are glued to the glass sheets.

Method according to one of the preceding claims, characterized in that a frame-shaped spacer is arranged between the glass panes, on which the glass frit can be applied. Method according to one of claims 4-6, characterized in that the additional vent hole is provided in a glass pane, in the frame-shaped spacer and / or in the applied border (is).

Method according to one of claims 4-7, characterized in that the closing of the vent hole is carried out at a temperature lower than the heat treatment step.

A method according to any one of claims 4-8, characterized in that a glass sheet provided with an open vent hole or a frame-shaped spacer provided with an open vent hole is used to carry out the method.

A method according to any one of claims 4-8, characterized in that a closed-vented glass sheet or a frame-shaped spacer provided with a closed vent hole is used to perform the method, the vent hole being opened prior to further evacuation. 11. The method according to any one of claims 4-10, characterized in that the vent hole is closed by melting and fusing a serving for sealing substance, wherein serving as the sealing substance, in particular glass material or glass frit material is used. A method according to claim 11, characterized in that the serving for sealing substance is fixed during the implementation of the method in the region of the vent hole.

Method according to one of claims 11 or 12, characterized in that serving for sealing sub-substance by laser action, inductive manner or by microwave energy and is melted.

Method according to one of claims 4-13, characterized in that a glass pane or a rahmenför Miger spacer is used with a arranged in a corner region vent hole.

Device for carrying out the method according to one of the preceding claims, characterized in that it is arranged as a heating system and cooling chambers (24, 25, 26, 27 is formed), wherein at least some of the ^¬ heating and cooling chambers (25, 26) are provided with terdruckerzeugungseinrichtungen UN.

Apparatus according to claim 15, characterized in that at least one heating chamber (26) comprises a closing device for the vent hole (8), wherein the closing device in particular a laser wear impactor, an induction device or a Mikrowellenbeaufschlagungseinrichtung is.