WO1997028947A1

WO1997028947A1 - Method for extruding a frame-shaped profiled rim onto a glass pane, extrusion die therefor, and resulting product

Info

Publication number: WO1997028947A1
Application number: PCT/FR1997/000226
Authority: WO
Inventors: Helmut Krumm; Herbert Joeris; Ulrich MÖLLEKEN; Heinz Scholl
Original assignee: Saint-Gobain Vitrage
Priority date: 1996-02-07
Filing date: 1997-02-05
Publication date: 1997-08-14
Also published as: KR19980703615A; JPH11503381A; DE19604397C1; EP0819050A1; MX9707659A; PL322595A1; BR9702069A; CZ317297A3

Abstract

A method for extruding a frame-shaped profiled rim (4) of elastomeric material onto the edge of a glass pane (1) having one or more sharp corners (2). The profiled rim (4) is provided with a radial sealing lip (8) projecting beyond the edge of the pane (1). In the corner area (2), the profiled rim (4) is laid along an arc of a circle. The extrusion die (14) used has an elongate slot covered at one end by a slide (16). The slide (16) is preferably coupled to a guide roller (17) rolling along the edge surface of the pane (1). The lip (8) is thus continuously elongated in the corner region, then continuously shortened again back to its original length. The resulting product, particularly glazing for use in motor vehicles, comprises, at the corners, a frame of which the lip, like the rest of the rim, is continuous with the adjacent linear portions.

Description

PROCESS FOR THE EXTRUSION OF A PROFILED CORD

FRAME SHAPED ON GLAZING, EXTRUSION PATHWAY

FOR THE EXECUTION OF THE PROCESS AND PRODUCT OBTAINED

The present invention relates to a method for the extrusion on the marginal zone of a plate comprising at least one angle, in particular a glazing, of a profiled cord in the form of a frame, having a lip projecting from the plate, into an elastomer , using an extrusion die, the profiled bead being placed in an arc in the corner area. The invention also relates to an extrusion die for carrying out this process and to the product obtained.

It is known to extrude profiles in the form of frames in an elastomer, comprising a sealing lip projecting radially, directly on the marginal zone of a glazing. This can be done, for example, by moving the extrusion die using a robot along the edge of the glazing. Processes of this type are described, for example, in documents EP 0 421 833 A2, 0 61 1 672 A2, 0 444 998 B1 and 0 479 677 B1. The extrusion process can also be carried out by moving the glazing using a robot relative to a fixed mounted extrusion die. Processes operating in this way are described in documents EP 0 585 1 29 A1, 0 634 263 A1,

0 662 384 A1 and 0 707 657 A1.

The known methods for the extrusion of a profiled frame comprising a centering and sealing lip projecting beyond the edge of the glazing in which, in general, a robot guides the extrusion head to the periphery of the glazing or where a robot moves the glazing in front of a fixed extrusion head, can be executed without difficulty, as long as the glazing or such shaped objects of plates, which are provided with the profiled frame, have rounded corners or a radius of at least about 20 mm. If the radius of the rounded angle is less than about 20 mm, or if the plate has one or more sharp angles, the known machines must then, if the extrusion speed must still be economical, deposit in the corner areas the profiled bead in an arc, the axis of the profiled bead then describing an arc of a radius of about 20 mm. This has the consequence that the sealing lip can no longer protrude in the corner area of a constant length beyond the edges of the glazing. In the case of a right angle, for example, the sealing lip directly in the angle would no longer extend beyond the edges, but would follow an arc inside the angle. In such a case, the peripheral lip, the function of which is to bear on the bodywork all around the glazing, could not fulfill its function.

It is therefore necessary in the prior art to complete, in a subsequent process step, the extruded profile frame in the corner areas. According to the process described in document EP 0 524 060 A1, the frame is completed by a method similar to the injection molding process. In this case, the marginal area to be completed is inserted into an injection mold, and a suitable polymer is injected into the injection mold and hardens in the mold. This process has proven its worth, but is however linked to additional labor costs due to the additional process steps required.

It is also advantageous in general to be able to modify, in one or more places on the periphery of the glazing, the relative position of the bead of the peripheral frame and of the end of the projecting lip. This is particularly the case if the edge of the bay where the glazing is inserted has in certain places a modulation, widening or shrinking, which it may be interesting to follow only with the lip without the essential part of the cord completely follow the meander in question. So it is essentially the lip which, thanks to its variable width in the place concerned, will resolve the problem.

The object of the invention is to improve the process mentioned at the beginning of this specification so that the lip projecting beyond the edge of the glazing is extended or completed in specific areas of the frame, without an additional process step. is not necessary.

This object is achieved according to the invention by the fact that an extrusion die is used comprising an elongated slot and a slide closing the end of the slot and that the slide is moved on command in a radial direction during the extrusion of the arc of a circle in the corner of the plate. The process according to the invention is therefore based on the use of an extrusion die with a variable die cross section, by the controlled modification of which the width of sealing lip in the corner area is continuously modified as desired in the area concerned and, in the case of a sharp angle, in which the lip is lengthened before reaching the angle and is then shortened again continuously to the initial length. Thus, it is also possible, also in the area of right or even acute angles, to form the frame completely extruded during the extrusion operation in such a way that a post-molding of the sealing lip, especially in the areas of angle is no longer necessary. The method according to the invention can be carried out in principle in the case of extrusion using an extrusion die carried along a stationary plate as well as using a die extrusion arranged in a fixed manner, at the level of which the glazing is moved.

The controlled displacement of the slide for lengthening and shortening the slot can be achieved in different ways. The slide can thus, for example, be provided with an electric or pneumatic drive, which is controlled by the central microprocessor of the installation. Instead, in particular in the corners, the slider can also be coupled to a lateral guide roller, which rolls on the peripheral surface of the plate to be provided with the profiled frame and moves the slider in the desired way, in particular when angle bypass.

Other features and advantages of the invention will emerge from the dependent claims and from the following description of an example of preferred embodiment based on the accompanying drawings.

In the accompanying drawings:

^• Figure 1 shows a corner area of a glazing unit comprising an extruded frame according to the state of the art; ^• Figure 2 shows the corner area of a glazing according to Figure 1, but with an extruded frame according to the method of the invention;

^• Figure 3 is a side elevational view of an extrusion head driven by a robot comprising an extrusion die according to the invention during the extrusion operation, and • Figure 4 is a schematic view of the extrusion operation in the corner area of the glazing.

The invention will be illustrated and described below in the context of use for glazing, in particular automotive glazing. However, the process of the invention can, of course, also be used in the case of the extrusion of profiled frames on other objects, such as, for example, metal plates, doors, trunk lids, etc. as far as these objects also have the need to modify the width of the lip, in particular when they have one or more sharp angles and the profiled frame is provided with a profile segment projecting beyond the edge of the object .

The glazing 1 shown in the drawings has a sharp angle 2 in the corner area, in this case an angle with a value of 90 °. Certain automobile windows are sometimes configured so as to present such a sharp angle, while their outline for the rest describes curves having a greater or lesser radius. Such forms of glazing are often found in fixed rear side glazing. Glazing with two sharp angles is often used for automobile rear windows; in this case, the two lower corners are usually in the form of sharp angles, while the two upper corners are more or less strongly rounded. In other cases, glazing, all of whose corners are right angles, is used. The process according to the invention can be used in all these cases.

On the glazing 1 is first of all applied, in the marginal zone, a layer 3 in the form of a frame of an opaque material, as a rule a baking ink. This is generally baked in the surface of the glass during the heat treatment to which the glazing is subjected with a view to bending and / or tempering. The profiled frame 4 is then extruded onto this layer 3 on the glazing at the level of the marginal zone of the glazing 1.

The profiled frame 4 has a base segment 5 and a wing 7 extending perpendicular thereto. The sealing lip 8 projecting outwards beyond the edge of the glazing is connected to the wing 7. On the base segment

5 is applied, during the mounting of the glazing, the mass of adhesive with which the glazing is glued to the fixing edge of the window frame of the bodywork. This profile segment 5 can also, in principle, have another cross section; if necessary, this base segment 5 can also be completely removed and the adhesive mass is then directly deposited on the glazing, preferably on the opaque layer 3. To obtain in the corner area a regular cross section, the die extrusion in its relative movement to the periphery of the glazing must describe in the corner a circular path, along which the axis of the profiled bead describes a curve of radius R, of dimension at least about 20 mm. Inevitably, the outer side 10 of the lip will also thus describe an arc of a circle around the same center of a circle with the consequence that, from the start of the rotation of the extrusion die, the lip part 8 protruding beyond the edge of the glazing will shorten. In the extreme outer corner area 1 1, the lip 8 does not even extend at all to the edge of the glazing. The phenomena are the same if the edge of the bay has a meander whose edge of the glazing does not have the equivalent, then the lip deviates or approaches the body unduly.

In the case of carrying out the method according to the invention, on the other hand, a suitable shape of the lip 8 is obtained and, in the case of a wedge, as it appears in FIG. 2. Since, in the angle zone, the pivoting movement of the extrusion die and its movement along a circular path remain in principle unchanged, the shape and shape of the profile segments 5 and 7 are, in principle, the same as in the case shown in Figure 1. The length I of the sealing lip 8 projecting outwards increases however continuously, from the point where the circular and rotational movement of the extrusion die begins, until the extrusion die has traversed half of the arc of a circle. At this point, the lip 8 has the length L.

Then, the length of the lip 8 decreases continuously, until it has again reached its original length I at the end of the circular arc. In this way, the lip 8 now has in the corner area of the glazing the shape as shown in FIG. 2, that is to say that the part of the lip protruding beyond the edges of the glazing also extends into the corner area parallel to the edge of the glazing, and only the extreme outer corner of the lip is somewhat rounded.

Figure 3 is a side elevational view of an extrusion head for the manufacture of the extruded profile frame according to the invention. The extrusion head comprises, inter alia, the die body proper 14 comprising the calibrated die orifice 1 5, the slide 1 6 being able to move horizontally and, in the case shown, where the extrusion head is controlled mechanically, a guide roller 1 7 connected to the slide 1 6, which rolls on the peripheral surface 1 8 of the glazing 1. The slot 1 5 ′ of the die orifice 1 5, forming the sealing lip, has a length L, which is substantially greater than the length I of the sealing lip in the region of the longitudinal edges of the glazing. The slot 1 5 ′ is closed at its end by the slide 1 6 to the point that the free lip slot 1 5 ′, has in the region of the rectilinear longitudinal edges of the glazing, the desired length I. The slide 1 6 and the bearing 1 9 carrying the guide roller 1 7, which are fixedly connected to each other, are slidably mounted via a sliding bearing 20 on a horizontal guide rod 21. A pressing force is exerted by the helical spring 22 on the slide device connected to the guide roller 1 7, the guide roller 1 7 therefore being pressed against the peripheral surface 1 8 of the glazing 1. The attachment 23 carrying the guide rod 21 is rigidly connected to the extrusion head carrying the extrusion die. The extrusion die 14 is provided with two channels 26, 27 separated from each other, through which the polymer to be extruded is brought to the die orifice 1 5, 1 5 '. The volume flow rate of the polymer can be adjusted in the two channels 26, 27 independently of each other, as described in the document EP O 444 998 B1. Valves regulating the volume flow in the two channels

26, 27 can be controlled preferably according to the position of the slide 16, and so that the volume flow in the channel 27 is increased and the volume flow in the channel 26 decreases as the lip slot 1 5 ' is more open. The volume flow rates are therefore adapted to the different mass requirements of polymer inside the die orifice during the rotation of the extrusion head.

FIG. 4 shows in a plan view the sequence of movements of the die 14 and of the slide 1 6 during the extrusion of the profiled frame 4 in a corner area of the glazing 1. It is recognized that the guide roller 1 7 progressing on the peripheral surface 1 8 moves, during the pivoting movement of the die 1 4, outward in the direction of arrow F with the slide 1 6 coupled to the roller guide, the die slot 1 5 ′ forming the lip 8 being thereby progressively released continuously. As soon as the guide roller reaches the angle 2 of the glazing during the pivoting movement of the die 14 which continues, the direction of movement of the slide 1 6 reverses, whereby the die slot 1 5 'becomes shorter again continuously, until it has reached its final position at the end of the pivoting movement of the die 14.

Unlike the previous methods, in particular that described in document EP 0 524 060 B1, the method of the invention makes it possible to obtain a product, automobile glazing in particular, which comprises in the corners, a frame whose lip, as the rest of the cord constitutes a continuity with the neighboring linear parts. In the prior techniques on the other hand, the connection between the new part molded in the corner and the parts of the neighboring extruded profile was visible except in the case where a cosmetic correction was made.

Claims

1. Method for the extrusion on the marginal zone of a plate comprising at least one angle, in particular a glazing, of a profiled bead in the form of a frame, having a lip projecting from the plate, made of an elastomer, using an extrusion die, the profiled bead being deposited in an arc of a circle in the corner area, characterized in that an extrusion die is used, comprising an elongated slot and a slide closing the end of the slot and in that the slider is moved on command in the radial direction during the extrusion of the arc in the corner of the plate.

2. Method according to claim 1, characterized in that the movement control of the slide is performed by a microprocessor also controlling the relative movement of the extrusion die and the glazing.

3. Method according to claim 1, characterized in that the movement control of the slide is performed by a guide roller coupled to the slide, which advances on the peripheral surface of the plate and is pressed against its peripheral edge.

4. Plate, in particular automobile glazing, equipped by extrusion according to claim 1, of a profiled cord in the form of a frame having a lip projecting from the plate, the plate comprising at least one angle in which the cord is deposited in an arc of a circle. , characterized in that in the corner of the plate, the end of the lip moves away from the rest of the bead and in that in the corner, the lip like the rest of the bead constitutes a continuity with the neighboring linear parts .

5. Device for carrying out the method according to claim 1, comprising an extrusion head carrying an extrusion die, a fixing device either for the plate to be provided with the extruded profiled bead or for the extrusion head and a automatic manipulator moving the extrusion die and the glazing relative to each other according to a predetermined program, characterized in that the extrusion die (14) has an elongated slot (1 5 ') and a slide ( 1 6) closing the elongated slot, a slide whose sliding movement can be controlled for lengthening and shortening the lip slot in the corner area of the plate as a function of the angular pivoting movement between the glazing and the die extrusion.

6. Device according to claim 5, characterized in that the slide is provided with a drive, which is controlled by a central microprocessor of the device.

7. Device according to claim 5, characterized in that the slide (1 6) is connected to a guide roller (1 7) rolling on the peripheral surface (18) of the plate, which is slidably mounted on a rod guide (21) together with the slide (1 6) parallel to the outlet plane of the die orifice (1 5).

8. Device according to claim 7, characterized in that the contact of the guide roller (1 7) with the peripheral surface is ensured by an elastic pressure means such as a helical spring (22).