WO1995011364A1

WO1995011364A1 - Process and device for assembling double-glazing units with frame-shaped spacers made of a plastic compound

Info

Publication number: WO1995011364A1
Application number: PCT/EP1994/003436
Authority: WO
Inventors: Rudolf Bernhard
Original assignee: Lenhardt Maschinenbau Gmbh
Priority date: 1993-10-20
Filing date: 1994-10-19
Publication date: 1995-04-27
Also published as: DE4335673C1

Abstract

In order to assemble double-glazing units with a frame-shaped spacer made of a plastic compound, at first the spacer is formed by continuously extruding the plastic mass as a viscous string on a support (17a) to which the mass adheres less well than to the glass panes (6, 26), then the spacer (7) is transferred from the support (17a) to one of the glass panes (26), both glass panes (6, 26) are made to coincide and are pressed together.

Description

Method and device for assembling insulating glass panes with frame-like spacers from a plastic mass

Description:

The invention is based on a method with the features specified in the preamble of claim 1 and on a device with the features specified in the preamble of claim 9.

For more than 15 years, insulating glass panes, which consist of glass panels, which are glued to one another at the edge with the interposition of a frame-shaped spacer, have been assembled in an almost vertical position in order to add a sag to the upper glass panel which is otherwise observed in a horizontal position during assembly avoid. Such a sag cannot be undone after the insulating glass pane has been assembled, if the interior of the insulating glass pane is hermetically sealed as a result. When plastic spacers are used, there is also the fact that they can flow under the weight of a glass sheet bearing on them, especially in the case of large-format and thick glass sheets, and when the plastic spacer is only immediately before the insulating glass pane is assembled by extrusion onto one of the glass sheets is applied, so that it is difficult in this way to produce spacers with a precisely predetermined thickness, ie insulating glass panes with a precisely predetermined air gap. In order to counter this disadvantage, it is known to embed balls in the plastic spacer, the diameter of which determines the distance between the glass sheets of the insulating glass pane (DE-C-41 04 108). However, this is an additional work step which is undesirable per se and makes production more expensive.

However, if, as usual, the plastic spacer is extruded onto an almost vertical glass sheet (EP-B-0 176 388), leaving a gap between the beginning and the end through which excess air can escape during assembly, then you have to struggle with the problem that the freshly extruded, still relatively soft plastic strand sags on the two horizontal edges or inclines downwards, and more so the larger the air gap in the insulating glass pane and thus the width of the spacer should be. This effect is particularly unpleasant because the thermal insulation effect of an insulating glass pane increases with an increasing air gap and the requirements for thermal insulation capacity are constantly increasing. As a countermeasure against the inclination of the extruded spacer, attempts have been made to let the nozzle with which the spacer is extruded follow a support roller which acts on the underside of the spacer in order to straighten it up. However, the duration of action of the support roller is necessarily too short to be sufficiently effective.

In order to avoid the described difficulty with the inclination of the plastic spacer, it is also known to embed a corrugated metal strip in the plastic spacer, which holds the spacer horizontally. However, such spacers cannot be extruded directly onto a glass sheet, rather a plastic strand with embedded metal strips must be prefabricated and then applied from a supply roll to the glass sheet with a special applicator, the change to other air gaps always being the same Changing the supply roll and threading the new strand into the applicator requires what is time consuming.

The present invention has for its object to show a way how to insulating glass panes with a frame-shaped, plastic spacer, which is only brief be before the actual assembly of a Isolierglasschei¬ is formed by extrusion, with exactly vorbestimm¬ tem distance (air gap) of the ^glass' panels voneinan¬ can assemble without sagging particularly wide spacer strands themselves.

This problem is solved by a method with the. Features specified in claim 1 and by a device with the features specified in claim 9. Advantageous developments of the invention are the subject of the dependent claims.

The invention leaves the path of extruding the plastic spacer directly onto one of the glass sheets of the insulating glass pane. The invention also leaves the way of prefabricating the plastic strand from which the spacer is formed as a strand and then processing it from the supply roll and continuously applying it along the edge to one of the glass sheets of the insulating glass pane. Rather, for the first time, the invention takes a third route in that the spacer frame is extruded directly onto a base, which is not one of the two glass plates which it is intended to keep at a distance in the insulating glass pane, but rather a base, on which the extruded mass adheres worse than on the glass sheets. Rather, the finished spacer is placed on one of the glass transferred plates. This can be done simply by pressing the spacer onto a glass sheet with the help of the base; because the spacer adheres better to the glass sheet than to the base, it stays on the glass sheet afterwards when the

Separate the glass panel and the base from each other.

Due to the fact that the spacer is no longer produced on the glass sheets by extrusion, but on a separate base, you no longer have to take the handling of the glass sheets into account when manufacturing the spacer, but also gain freedom and time Scope to stabilize the spacer in its desired shape before it is transferred to a glass sheet. It has been shown that the time required to adequately stabilize the spacer is only short, so that the extrusion of the spacer can take place shortly before the spacer is placed on its glass sheet, so that an expensive one It is not necessary to store or temporarily store the spacers.

A thermoplastic compound, in particular a polyisobutylene, is usually used for the spacer. In this case, the mass extruded onto the pad is preferred on the pad cooled, for example by blowing with cold air, but particularly preferably in that the base itself is cooled, for example in that the base is a plate with cooling channels through which a coolant flows. If the mass from which the spacer is extruded is, however, a crosslinking plastic, then this is preferably heated on the base to accelerate the crosslinking, in particular by the base itself being heated, for example by in electrical heating conductor inserted.

The method is preferably carried out in such a way that the base is kept horizontal while the mass is being applied and is brought into a vertical or almost vertical position for transferring the spacer onto a glass sheet of a pair of glass sheets. In this way, the advantages of a vertical insulating glass assembly line are combined with the advantages of a horizontal method of operation without having to accept the respective disadvantages. The glass sheets can be moved and handled in a manner known per se on a horizontal conveyor and leaning against a support device through an assembly line during the entire manufacturing process. The vertical is used only for the purpose of producing a plastic spacer by extrusion Working method deviated by extruding the spacer onto a horizontal or approximately horizontal surface. During the extrusion in a horizontal position, the internal cohesion of the initially still pasty plastic mass, which is usually a polyisobutylene heated to 70 ° C. to 80 ° C., is sufficient for even the largest air gaps or air spaces to occur To prevent spacer widths from tilting to the side, although it is relatively soft and flowable when hot extruded. You don't even need rollers trailing the extrusion nozzle to straighten the spacer, which is advantageous because the freshly extruded strand is very sticky. As a result, the freshly extruded strand cools down by giving off heat to the base and to the ambient air and solidifies progressively, which can be accelerated by additional cooling of the base and / or the strand. The spacer, solidified in the horizontal position and thus stabilized in its shape, can then easily be swung up with the base into a vertical or almost vertical position in order to press it onto a glass sheet without the spacer being able to complete the assembly of the insulating glass pane still sagging. The actual assembly takes place in the almost vertical position of the glass panels, in which an undesired glass panel sag is avoided and in which the air space of the insulating glass pane, that is the width of the spacer which is compressed after the glass sheets have been compressed, is not determined by the weight of a glass sheet resting thereon, but solely by the pressing process, which is usually carried out in a plate press with a calibrated plate spacing.

In this way, perfectly calibrated insulating glass is obtained with extruded, plastic spacers that run exactly straight, even with large spacer widths.

The period of time in which the spacer is extruded onto the base can be used to position the first glass sheet of a pair of glass sheets at that point, namely in an assembly and pressing device in which the actual assembly is to take place. For this reason, the first glass sheet is preferably conveyed into the assembly and pressing device in its almost vertical position and is offset and held therein parallel to itself, transversely to the conveying direction. The second glass sheet following the first glass sheet is stopped in the meantime in front of the assembly and pressing device in the swiveling area of the support, coated with the previously extruded spacer by swiveling up the support, then conveyed into the assembly and pressing device, where it is positioned congruently with the first glass sheet and assembled by closing the press with the first glass sheet. Once the pad has passed the extruded spacer on the second glass panel, it swings into its horizontal position ^'back and is immediately ready to extrude on her a spacer for the next Glastafel- few, and for at least for the assembly and pressing of the preceding insulating glass pane is available, because only when the pressing process has ended and the insulating glass pane has been conveyed out of the assembly and pressing device can the first glass sheet for the next insulating glass pane enter the assembly and pressing device and the following glass ¬ panel are positioned in front of the assembly and pressing device in order to receive the next spacer. Since the spacer is not extruded directly onto a glass sheet standing on the horizontal conveyor, which inhibits transport, the method according to the invention can even shorten the cycle time in the production of insulating glass, especially since the pivoting movement of the lower part can take place very quickly, since it can be constructed very easily, since it only has to carry a spacer, the weight of which - compared to the weight of a glass sheet - is low. A light pad can be moved very quickly due to its low inertia.

In the assembly and pressing device, which is preferably designed as a plate press, the iso- glass pane pressed onto a preselected air gap. The spacer widens due to the compression that occurs. Since the extent of the compression is known, the extent of the widening is also known. In a further development of the invention, the spacer is therefore extruded onto the base in such a way that it has a waist between its underside lying on the glass sheet and the surface facing away from it, which is dimensioned such that it disappears in the press due to the subsequent upsetting. Such a method of operation would not be possible when extruding the spacer onto an approximately vertically standing glass sheet, because the waist would further increase the sagging or tipping of the spacer strand at its horizontal sections. When extruding the spacer onto a vertically standing glass panel, would the opposite be advisable, namely a bulbous design of the spacer profile _? to stabilize the spacer profile, which would, however, lead to a very bulbous surface of the spacer that is visible in the insulating glass pane and therefore undesirable.

In the case of insulating glass panes which are assembled under normal ambient air pressure, the plastic spacer has so far been applied in such a way that a gap remains in the spacer between the beginning and the end, which means that when the iso- glass can escape the air, which is displaced by the considerable compression of the spacer. So far, this gap has only been closed after the insulating glass has been pressed, which requires an additional work step, and there remains a weak point for the penetration of water vapor. The ends of the spacer are particularly at risk from sagging until the insulating glass pane is assembled if they are located in the horizontal section of the spacer. In a development of the invention, the spacer is therefore preferably extruded onto the base without gaps, and this measure is combined with one or both glass sheets, in particular at a corner, being bent away from the spacer before they are assembled and pressed to form the insulating glass pane. As a result, the excess air when pressing the insulating glass pane can escape from the insulating glass pane despite the gap-free spacer, and only then is the insulating glass pane closed in its last corner by reversing the bend. A press suitable for this purpose is known from WO 89/11021 and from DE-U-9014304 for another purpose, namely for filling a foreign gas into an insulating glass pane.

For the construction of the device according to the invention, one expediently starts from a vertically working production line for insulating glass with plastic Spacers. Such a production line has a horizontal conveyor, on which the glass sheets are conveyed standing and leaning against an almost vertical support device through various successive stations. One of these stations is an assembly and pressing device which, opposite the support device on which the glass sheets enter the assembly and pressing device, has a holding device, in particular in the form of a plate over which openings are distributed, through the air is sucked in, so that with this plate a glass panel leaning against the support device can be sucked in and lifted off parallel to itself. According to the invention, there is a tilting table in front of the assembly and pressing device, which can be pivoted about an axis parallel to the conveying direction and the surface of which is designed in such a way that the plastic mass of the spacer adheres to it less than on the glass sheets. A movable nozzle is assigned to this tilting table, through which a spacer can be extruded on the tilting table. By pivoting the tilting table up, the spacer can be placed on a glass sheet which has been stopped in a predetermined position on the horizontal conveyor and is leaned against the approximately vertical support device, so that it adheres to the glass when the tilting table is pivoted back. The surface of the tilt For this purpose, the table consists of a plastic, in particular a silicone, on which the spacer does not adhere well, in any case worse than on the glass sheet. The plastic is preferably located as a thin layer on a metallic plate, which consists in particular of an aluminum material. This makes it possible for the hot extruded spacer to cool down and solidify quickly, particularly when the tilting table has a cooling device for its surface. If thermosetting compositions are also to be processed with the device, then the tilting table preferably also has a heating device for its surface in order to promote the crosslinking of the thermosetting composition.

The nozzle with which the spacer is extruded can be located at the end of a three-dimensionally movable, program-controlled robot arm; however, it is preferably located on a support which can be moved along a crossmember which in turn can be moved across the tilting table transversely to its longitudinal direction. The traverse expediently extends at right angles to the horizontal conveyor, because then, when the spacer is extruded, it can be moved out of the pivoting area of the tilting table in a particularly short way.

To achieve particularly short cycle times, the The tilting table can be divided transversely to the horizontal conveyor into two sections which can be moved together or independently of one another, on which two smaller spacers can be coated successively, in order then to be successively transferred to two glass panels positioned opposite them. Accordingly, the smaller insulating glass panes in the assembly and pressing device could also be assembled and pressed together. For large-format glass panels that are longer than one section of the tilting table, the two sections of the tilting table can be moved together in synchronism in order to apply an extruded spacer extending over both sections of the tilting table to a correspondingly large-sized glass panel.

According to another development of the invention, the layer of plastic that covers the tilting table could be a film that can be moved over the plate of the tilting table, in particular an endless film, from time to time to remove unused or, in the meantime, cleaned areas of the film to be able to study.

Instead of only heating or cooling the tilting table, one could use the tilting table and the section of the horizontal conveyor assigned to it, including the section above it arranged support device surrounded by an air-conditioned housing. This allows you to control the problems with condensing moisture that may otherwise occur on the spacer during cooling.

Exemplary embodiments of the invention are shown schematically in the accompanying drawings.

FIG. 1 is a plan view of a section of a vertical insulating glass production line,

FIG. 2 shows the view II-II according to FIG. 1 of that station in the insulating glass production line, in which a plastic spacer is extruded onto a tilting table, with a cut cross member,

FIG. 3 shows the station from FIG. 2, but with the tilting table swung up and cut

Traverse, and

FIG. 4 shows a top view of another insulating glass production line with two tilting tables in the station for extruding plastic spacers.

In the two exemplary embodiments, identical or corresponding parts are labeled with corresponding reference numbers. A horizontal conveyor 1 divided into several sections leads through the section of the insulating glass production line shown in FIG. 1, each formed from a horizontally running roller conveyor 2 on which the glass sheets are conveyed standing up and from a support device 3 which runs almost vertically and which the glass panels are leaning against during conveyance. The support device 3 is preferably an air cushion wall, but could also be formed by a field of driven or non-driven rollers.

The production line shows an intermediate transport path 4, which comes, for example, from a washing machine, a station 5 in which plastic spacers 7 are extruded, a further intermediate transport path 8, an assembly and pressing device 9, of which one is usually one another conveyor track section leads to a sealing station.

The direction of conveyance is indicated by the arrow 11,

The assembly and pressing device 9 has a fixed air cushion wall 12 as a supporting device for the glass panels, which run into the assembly and pressing device on the horizontal conveyor 1. The horizontal conveyor 1 passes through the assembly and pressing device 9. In this lies the fixed air cushion wall 12 opposite a pressing plate 13 running parallel thereto, the distance to the air cushion wall 12 can be changed by a press drive, by means of which the pressing plate 13 can be displaced parallel to itself. The press plate 13 has numerous air intake openings over its surface, through which air and with it glass sheets can be sucked in and held.

The station 5 has a tilting table 16 which can be moved on rails 14 and 15 which run at right angles to the conveying direction 11, the table top 17 of which is made of aluminum and has a thin silicon layer 17a on the surface. Channels 17b for a coolant run in the table top. On both sides next to the tilting table 16, two rails 18 and 19 run transversely to the conveying direction 11 and rest on two stands 20 and 21. A traverse 22 parallel to the conveying direction 11 can be moved transversely to the conveying direction 11 over the tilting table 16 tilted into the horizontal position (FIG. 2). Along the traverse 22, i.e. The carrier 23, which carries a nozzle 24 through which a plastic spacer 7 can be extruded, can be moved parallel to the conveying direction 11. The nozzle 24 is fed by an arrangement 25 comprising a pump and a reservoir.

The device works as follows: Two glass sheets, which are to be assembled to form an insulating glass pane, are conveyed successively by the horizontal conveyor 1. The first glass sheet runs up to the intermediate transport section 8 in front of the assembly and pressing device 9 and waits in front of it until the preceding assembly and pressing process therein has ended and the device 9 has been opened again, in order then to enter the assembly and Press device to break in. At the same time, on the tilting table 16, which is in its horizontal position, a frame-shaped, closed, plastic spacer 7 is formed by the nozzle 24, which can be moved parallel and perpendicular to the conveying direction 11. The first glass sheet is followed by the second glass sheet 26 up to the station 5, in which it is stopped in a predetermined position, preferably with its front edge near the outlet side of the station 5, exactly opposite the spacer 7. As soon as this has happened and a preselected cooling time of a few seconds, for example from 5 to 10 s, has elapsed, the tilting table 16 is moved on the rails 14 and 15 against the horizontal conveyor 1 and at the same time swiveled up, as a result of which the spacer 7 contacts the second glass sheet 26 is pressed lightly so that it adheres to it when the tilting table is immediately pivoted back into its horizontal starting position and by the horizontal conveyor 1 is driven away.

In the meantime, the first glass sheet has run into the assembly and pressing device 9, stopped there in a predetermined position, sucked in by the pressing plate 13 and removed from the horizontal conveyor 1 by moving the pressing plate 13 back, so that the horizontal conveyor in the area of the assembling and pressing device 9 is free again. Now the second glass sheet 26 covered with the spacer 7 is conveyed into the assembly and pressing device 9, stopped there congruent with the first glass sheet, and the pressure plate 13 is moved against the air cushion wall 12 in order to join the two glass sheets and compress the spacer 7 together to be glued and pressed to a predetermined thickness.

After the pressing process is complete, the assembly and pressing device 9 is opened and the insulating glass pane is removed.

In the case of smaller pane formats, two spacers 7 can be extruded next to one another in the station 5 and placed on two glass plates in order to subsequently join them together in the assembly and pressing device 9 with two glass plates previously positioned therein and held on the press plate 13. To be there To achieve a gain in cycle time, the station 5, possibly also the assembly and pressing device 9, can be divided into two successive sections 5a and 5b in the conveying direction 11, each of which has a tilting table 16a and 16b, which has a section ¬ section of the support wall 3 opposite, which is divided, but can also be undivided. The two tilting tables 16a and 16b can be moved independently. In a departure from the first exemplary embodiment, in FIG. 4 the carrier 23 with the nozzle 24 is also movably supported on a cantilever arm 42 which extends transversely to the conveying direction 11 and which is attached to a carriage 43 which in turn is mounted on two rails 44 and 45 runs in the vicinity of the arrangement 25 of the pump and reservoir. The cantilever arm 42 has its starting position and end position between the tilting tables 16a and 16b and can alternately operate both from there at short notice. As a result, short cycle times of the production line and at the same time sufficient hardening times for the spacers 7 are possible before they are swiveled up.

A corresponding design of the device for moving the nozzle 24 as in FIG. 4 could also be used in the first exemplary embodiment. The starting point for the nozzle is expediently chosen such that it lies in the region of a leg of the spacer 7 running transversely to the conveying direction 1, just before the corner to the leg to be extruded next, parallel to the conveying direction 1, so that the leg Conveying direction 11 parallel legs are produced as early as possible and thereby have longer time to solidify than the legs of the spacer 7 running transverse to the conveying direction 11.

Instead of using a nozzle, the plastic spacers could also be extruded through two nozzles to be used simultaneously, which have a common starting point and a common end point; this can reduce the cycle time in station 5.

Claims

Claims:

1. A method for assembling insulating glass panes by applying a frame-shaped spacer (7) made of a plastic mass to a second glass sheet (26) along its edges and joining the second glass sheet (26) with a first glass sheet (6), see above that the spacer (7) adheres to both glass sheets (6, 26), characterized in that the plastic mass initially continuously as a pasty strand on a base (17a) on which the mass adheres less than on the second glass sheet (26), applied and thereby the frame-shaped spacer (7) is formed,

and that the spacer (7) is then transferred from the underlay (17a) to the second glass sheet (26).

2. The method according to claim 1, characterized in that the mass is a thermoplastic and is cooled on the base (17a).

3. The method according to claim 2, characterized in that the base (17a) is cooled.

4. The method according to claim 1, characterized in that the mass is a crosslinking plastic and is heated on the base (17a) to accelerate the crosslinking.

5. The method according to claim 4, characterized in that the base (17a) is heated.

6. The method according to any one of the preceding claims, characterized in that the strand of the plastic mass is applied to the base (17a) in such a way that it has a waist between its underside lying on the base (17a) and the surface facing away from it Has.

7. The method according to any one of the preceding claims, characterized in that the base (17a) is kept horizontal or almost horizontal during the application of the mass and for transferring the spacer (7) onto the second glass sheet (26) in a vertical or almost vertical position is brought.

8. The method according to any one of the preceding claims, characterized in that the plastic spacer (7) is applied without gaps to the base (17a) and from there is transferred to the second glass sheet (26), and that before Assembling and pressing the insulating glass pane at least one of the glass sheets (6, 26) at the edge, preferably at a corner, from the Spacers (7) are bent away elastically, the insulating glass pane is assembled and pressed in the bent state and the bending is finally reversed.

9. Device for assembling insulating glass panes with plastic spacers between pairs of glass panels,

with a support device (12) for supporting a second glass sheet (26) in an almost vertical position,

with a holding device (13) for a first glass sheet (6) provided at a variable distance from the support device (12), the holding device (13) and the support device (12) being able to be pressed against one another in a position parallel to one another,

and with a horizontal conveyor (1) for the glass sheets (6, 26) leading through the area of the support device (12) and the holding device (13),

characterized in that a tilting table (16) pivotable about an axis parallel to the horizontal conveyor (1) is provided, on the surface (17a) of which the plastic mass adheres less than on the glass panels (26), and in that the tilting table (16) a nozzle (24), which is movable relative to the tilting table (16) and parallel to its surface (17a), is associated with the surface (17a) which is associated with the pasty mass is fed so that the nozzle (24) applies the mass as a strand to the tilting table (16) as a base.

10. The device according to claim 9, characterized in that the surface (17a) of the tilting table (16) is formed from a plastic, in particular from a silicone.

11. The device according to claim 10, characterized gekennzeich¬ net that the plastic is as a thin layer (17a) on a metallic plate (17).

12. The device according to claim 11, characterized in that the metallic plate (17) consists of an aluminum material.

13. Device according to one of claims 9 to 12, characterized in that the tilting table (16) has a cooling device (17b) for its surface (17a).

14. Device according to one of claims 9 to 12, characterized in that the tilting table (16) has a heating device for its surface.

15. The device according to one of claims 9 to 14, characterized in that the table top in the space between the support device (12) and holding device (13) is retractable.

16. Device according to one of claims 9 to 14, characterized in that the tilting table (16) with respect to the conveying direction (11) of the horizontal conveyor (1) is arranged in front of the holding device (13) and against one in front of the holding device ( 13) lying section of the support device (3) can be moved.

17. Device according to one of claims 9 to 16, characterized in that the nozzle (24) is attached to the end of a three-dimensionally movable robot arm.

18. Device according to one of claims 9 to 16, characterized in that the nozzle (24) can be moved along a crossmember (22) which on its side can be moved across the tilting table (16) transversely to its longitudinal direction.

19. The apparatus according to claim 18, characterized gekenn¬ characterized in that the cross member (22) extends parallel to the horizontal conveyor (1).

20. Device according to one of claims 9 to 17, characterized in that the nozzle (24) can be moved along a cantilever arm (42) which extends at right angles to the horizontal conveyor (1) and is attached to a carriage (43) which is movable on rails (44, 45) which run parallel to the horizontal conveyor (1) on the side of the tilting table (16) facing away from it.

21. Device according to one of claims 9 to 20, characterized in that the tilting table (16) transversely to the horizontal conveyor (1) is divided into two sections (16a, 16b) which can be moved together or independently of one another.

22. The apparatus of claim 20 and 21, characterized ge indicates that the cantilever arm (42)

Starting position between the two tilting tables (16a, 16b).

23. The device according to claim 11, characterized gekenn¬ characterized in that the layer (17a) made of plastic is a movable over the plate (17b) film.

24. Device according to one of claims 9 to 21, characterized in that it is surrounded by an air-conditioned housing.