Apparatus for braking glass panes scored at only one side.

The invention relates to a device for breaking unilaterally scored glass plates, with a trained, for example, as a table surface for the scored glass sheet with a pair of upwardly against the glass sheet acting abutment, which are mutually aligned substantially parallel, and a bottom between the abutments against the glass sheet can be applied lifting strip or roller.

Such devices, which are also called Brechtian are provided in connection with glass cutting tables, to break the glass cutting tables side scored glass panels along the scribe lines to the desired formats. The crushing process to the tables crushing takes place thereby that a bar or a roller is lifted from the supporting surface from the bottom, while abut from above against the glass sheet arranged two on either side of the bar or roller abutment. During the crushing operation, arises between the top surface of the glass sheet and this pressing-down abutment a relative movement, so that the surface of the glass sheets and, in particular scratched existing coatings can be destroyed there at most. the risk of scratching of glass or of damaging of coatings on the glass sheets is increased by the fact that the crushing process very fine glass splinters, which, when they enter between the abutment and the glass panels, perform during the crushing operation to scratches in the glass sheet.

A device with the features of the introductory part of the independent claim 1 is known from DE-A-34 28 863 ad.

The FR-A-2070212 and the corresponding US-A-3,693,852 show a device for dividing scored glass plates, in which only one abutment is provided. In the apparatus known from FR-A-2070212 a lifting strip or roller is provided, which is raised at break from a retracted position in the table. In the apparatus according to FR-A-2,070,212, the abutment is a single, hollow beam, which has on its side facing the glass sheet, two rows of outlet openings for gas. The arrangements under this hollow bar roller is constantly higher than the rollers of the provided on both sides of the roller bearing surfaces. The known device is suitable for breaking a continuously moving glass ribbon (float glass) along transversely to the longitudinal direction (= direction of motion) of the glass ribbon extending score lines. The from the FR-A 2,070,212 known device operates so that the roll over the moving glass sheet is bent by the escaping gas, so that it splits along the scribe lines previously generated in him.

The invention is based on the object to provide a device of the aforementioned type, with the particular one side provided with a coating glass panels with no risk of damaging the glass sheets and in particular the coating may be broken.

This is inventively achieved in that the abutments are constructed as known hollow in itself, at its the glass sheet facing the bottom outlet openings for a gaseous medium to have, and are connected to at least one source for the pressurized gaseous medium, in particular air, that the support surface or the glass sheet facing the lower side of the abutment is formed obliquely, wherein the the lifting strip or roller adjacent lower edges of the abutment are arranged higher than the other lower edges thereof.

The Brechtian invention, the abutments are not at the top of the glass sheet which is to break, but to push this down by a formed between them and the glass sheet cushion. In this manner, destructive relative movements between the abutments and the glass sheets are excluded on the surface of glass sheets and there possibly provided coatings.

Another advantage of the device according to the invention is that the abutment, in contrast to present on the glass sheet abutments need not be adjusted exactly to the thickness of the glass sheet to breaking. This is because the hold-down force under the abutments according to the invention exerted on the glass sheet on the air cushion with thicker glass sheets (smaller distance) is greater and with thinner glass sheets (larger spacing) is smaller. Thus, the need for breaking glass sheets thinner smaller hold-down force is applied without moving the abutment in vertical direction automatically. This hold-down force increases with thicker glass sheets without adjusting the abutment, so that then the greater holding force is produced as it is needed for breaking thicker glass sheets. So can be broken, for example, glass plates with a thickness between 2 and 10 mm without vertical adjustment of the abutment.

Characterized in that in the invention the the support surface or the glass sheet facing the lower side of the abutment is formed obliquely, wherein the the lifting strip or roller adjacent lower edges of the abutment are arranged higher than the other lower edges thereof, it is avoided that even with almost arranged above the glass sheet abutments, the glass sheets during the crushing operation under the action of the lifting strip or roller applied to the facing lower edges of the abutment.

The openings in the abutments can be round nozzles. it is preferred however that the outlet openings are formed for the gaseous medium as a slot nozzle or as a continuous slot nozzle. It can be next to each other more, be provided in the longitudinal direction of the abutments extending rows of slot dies or multiple juxtaposed, through slot nozzles. In this way, a particularly strong air cushion between the abutments and the glass sheet is formed.

Further details and features of the invention will become apparent from the following description of embodiments, with reference to the accompanying drawings. It shows<ul><li>Fig. 1 in cross-section an apparatus for breaking-sided scored glass plates and</li><li>Fig. 2 is a arranged in connection with a glass cutting table, not shown, breaking table with a location for static and a dynamic point to the breaking of glass sheets.</li></ul>

A device only shown in its essential parts for breaking scored glass side panels has a supporting surface 1, which is designed for example as a table. On the support surface 1, a glass sheet 2 which is a coating, for example a vapor-deposited metal layer 3 carries on its upper side, conveyed forward in the direction of arrow 4th The glass sheet 2 is moved long in the direction of arrow 4, to an opening provided at its top scoring is arranged exactly over a 5 arranged in a slot 6 of the supporting surface 1 lifting strip 7th The lifting bar 7 is raised in the direction of the double arrow 8 and lowered.

Above the supporting surface 1 7 abutments on both sides of the lifting strip provided 9 and 10, the distance in the direction of the double arrows 11 from each other is variable, wherein the abutments 9 and 10 remain from each other, oriented symmetrically to the lifting bar 7 also with a change of their distance.

For any possible adaptation to different thicknesses of the glass sheets 2 and possibly also to assist the breaking operation, the abutment 9 and 10 relative to the support surface 1 raised and lowered in the direction of the double arrow 12th

As shown in Fig. 1, the abutments 9 and 10 are hollow and have on their, the glass sheet 2 facing surface (wall 13) a plurality of air outlet openings 14.

The air outlet openings 14 are formed in the embodiment shown as a rotary nozzle with three rows are provided of circular nozzles 14, which extend in the longitudinal direction of the abutments 9 and 10 respectively.

To the ends of the abutments 9 and 10 are lines for supplying gas under pressure, in particular connected air, wherein the supplied compressed air then flows out through the nozzles 14 of the abutments 9 and 10, so that the glass panel 2 is pressed against the support surface 1 , When lifting the lifting bar 7 (optionally in combination with a lowering of the abutments 9 and 10), the glass sheet 2 along the score line 5 is broken without the abutments 9 and 10 physically with the glass sheet 2 and the thereon coating 3 in touch reach.

As shown in FIG. 1, the wall 13 of the abutment 9 and 10 is designed such that it extends obliquely to the supporting surface 1, wherein the the abutment 10 adjacent edge 15 of the support surface 1 at a greater distance than the other edge 16 of the abutment 9 and 10. in addition the underside of the wall 13 is formed convexly in the longitudinal direction of the abutments 9 and 10. FIG.

The abutments 9 and 10 for example, have a width of 10 cm and up to 3 m long, depending on the size of the glass cutting table.

In FIG. 2, a breaking table 20 is shown in which a breaking point 21 for static breaking and a breaking point 22 is provided for dynamic breaking of glass sheets 2 with scorings fifth The crushing point 21 to the static breaking, as shown in Fig. 1, carried out. The resulting by breaking along the scorings 5 glass strips which still have scorings 23 will be lowered to the supporting surface 1 conveyor belts 24 in the direction of arrow 25 and subsequently through Tr 26 promoted ansportbänder in the direction of arrow 27 to the dynamic crushing place 22nd The dynamic breaking point 22 corresponds with the exception that in place of the breaking bar 7 a liftable crushing roller 28 is provided which is rotationally driven in the direction of arrows 29, the static breaking point having the structure shown in FIG. 1. In the dynamic breaking point 22, the glass strips, which come from the static breaking point 21 can be broken in a continuous process along the scorings 23rd

In principle, it should be noted that a static refraction which are provided with scorings five glass sheets 2 in the first place for thicker slices and smaller distances between the scorings 5 ​​from each other is suited, whereas a dynamic refractive primarily for cross-breaking (see. Figs. 2 and the associated description) is suitable, and preferably thinner glass sheets or panes of glass, the greater distances of the scorings from one another to be broken in the dynamic breaking process. The crushing roller 28 serves not only to the glass sheets to break in cooperation with the abutments 9 and 10 to bend, but also for the transport of glass plates 2 through the dynamic breaking station 22nd

At the abutment side facing the abutment 9 of the refractive body 22 additional nozzles 30 can be arranged (Fig. 3), from which gas, in particular air, flows downwards. This measure prevents the front edge of the glass sheet too far apart from the support surface 1 and may abut on the abutment. 9 The nozzles are preferably arranged higher than the nozzles 14 of the abutment. 9

It should also be pointed out that the breaking table shown in FIG. 2 need not necessarily be formed angled, it can also be straight.