DE10344444B4 - Process for the partial forming of glass plates, glass or glass ceramic plate with partially formed partial areas and use of this plate - Google Patents

Abstract

method for partially forming a glass plate in at least one predetermined Partial area by gravity lowering in the at least partially reheated Glass plate, being in the glass plate before partial forming in the predetermined sub-area according to its nominal contour a material taper is attached, characterized in that the attachment of the material taper in the glass plate in its shaping from the molten state he follows.

Description

The The invention relates to a method of partial forming a glass plate in at least a predetermined portion by Gravity lowering in the at least partially reheated glass plate, being in the glass plate before the partial forming in the given Subregion mounted according to its nominal contour a material taper becomes.

The The invention further relates to a glass or glass ceramic plate with partially reshaped parts according to the preamble of Claim 9.

Finally, refers The invention relates to a use of this glass or glass ceramic plate.

Glass- or glass ceramic plates with partially formed partial areas win getting stronger in the market in importance, especially in glass ceramic products for domestic Range, typically on cooktops of cooktops or at Cover discs for Living room fireplaces. But other applications are also possible, e.g. Glass baking cups.

Cooking surfaces off Glass ceramics or special glass have been on the market for many years proven. Especially become glass ceramic cooking surfaces used for the heating of electric cooking places and those with gas burners, both with in the cooking surface used atmospheric Gas burners as well as with radiant burners under the cooking surface. In recently, Time is also more and more inductively heated cooking appliances offered.

Next the use of this glass ceramic cooking surface for indirect food preparation, i. for heating food in a cookware, there is also the Possibility, Glass-ceramic cooktops for direct food preparation, e.g. by crickets, to use.

It is usual here a plane, usually rectangular cut cooking surface than base for to use the hob design.

For different Fields of application or functional areas of the hob is however, desirable the cooking surface to have reshaped in partial areas. This transformation can serve Frame sections or even controllers or touch-control areas separate from the active cooking area. For gas appliances, it is also desirable Subareas - in particular in the back of the cooking surface - to buckle to primary air for the To suck in gas burners or hot, Exhaust with gas burners from the space below the cooking surface or remove from the furnace area.

Of further it is desirable with open gas burners around the opening edge around a bent, i. to have a raised area, the an intrusion of overcooking or cleaning fluid prevented in the hob. They are also oval or round-sided breakthroughs for ventilation of the device interior or mounting a fume hood raised edge portions of these breakthroughs desirable. Also, the all-round raising of the cooking surface or the formation of tableau areas is functional and aesthetic Improvement of the device desirable.

since Some years are also cooking surfaces Special glass or glass ceramic on the market, with partially reshaped Partial areas are equipped and thus the desirable additional function very good fulfillment. These cooking surfaces are in the production, however, only at considerable cost to manufacture. Or at a reasonable cost only with serious technical limitations.

In a known method ( EP 0 834 044 B1 ), the hot, plastic glass ribbon drawn directly from the melting tank is continuously placed on rotating molds, and partially formed by vacuum drawing or compression molding in the intended areas according to the desired contour, to then be divided into individual plates.

adversely In this process, once the high cost of the special mold tools and on the other hand the high number of pieces, which has to be produced to maintain the continuous melting process, which an expensive and inflexible storage with it pulls.

Further Methods are described which start from a flat glass plate, which in a subsequent separate production step, in particular with short-wave IR radiation is heated up again and then over Known molding process using appropriate molds via vacuum or pressing in the desired Shaping is brought.

in both methods described above, the partially deformed glass plate the final product be, or it forms a so-called green glass plate, which then by known thermal treatment stages ceramized to a glass ceramic plate becomes.

Furthermore, it is through the EP 0 879 797 A1 known, glass plates for cooking surfaces on one side, or holes in cooking surfaces circumferentially by underlaying bars or support rings to transform in the ceramization solely by gravity. This method on the basis of gravity lowering, which in itself works very well and is also inexpensive to implement, has the disadvantage that only very small degrees of deformation can be achieved without additional forced forming. These low degrees of deformation rarely fulfill the desired functions.

Similar Procedures are used in the manufacture of transformations for chimney windows applied.

cover plates for living room fireplaces, so-called Kaminsichtscheiben, are today according to the prior art preferably of a transparent glass ceramic with sufficient heat resistance produced. The cover plates are available as flat, curved or folded embodiment. Furthermore, disc versions become known, in the middle range round or oval from the Arched out level are.

folded or bulbous bulging Fireplace panes made of glass ceramic are based on a plan Molding material (green glass) in a separate additional Work process heated up again, in particular to soften the bending areas, then a deformation these areas by gravity lowering on appropriately shaped To ensure documentation. Subsequently, this deformed disc ceramifies. In the case of the spherical molded lenses is a heating of the entire disc with following Forced deformation over For example. Vacuum required to achieve the ge desired degree of deformation. After this process step is also a ceramization in one appropriate form required. This additional step of forced forming is cost and time-consuming.

By the generic DE 1 246 939 B a method for partially forming a glass plate in at least one predetermined sub-area by gravity lowering in the at least partially reheated glass plate has become known, wherein in the glass plate before the partial forming in the predetermined portion corresponding to its desired contour, a material taper is applied.

in the known case, the material taper by an example V-shaped groove formed by any known glass cutting or grinding process is generated, for example by means of a grinding wheel with V-shaped Profile.

A corresponding state of the art also shows the DE 25 03 467 C2 ,

By this rejuvenation in the reshaped portions of the glass plate can then deform during gravity a targeted to partial areas concentrated forming process realized because of the rejuvenation reduced in the corresponding sections of the moment of resistance and at the same bending moment, due to the same gravitational force continues to act on this area, the specific bending force per unit area gets bigger, whereby the deformation concentrates on these tapered areas. By the rejuvenation is it therefore possible to combine the advantages of the two known shaping methods, i.e. the high degree of deformation in the complex molding process with additional Forced forming tools with the easy to perform Shaping process by Gravity lowering with bases of simple bars or rings under the reheated Glass plate.

The Generation of material rejuvenation By grinding, however, is very complex, not only in time, but also with regard to the procedure and the necessary equipment. Each must single glass plate after its shaping in an additional Step be subjected to this grinding process.

Of the Invention is based on the object, the initially described method for partially forming a glass plate in at least one predetermined Partial area by gravity lowering in the at least partially reheated Glass plate, being in the glass plate before partial forming in the predetermined sub-area according to its nominal contour a material taper is attached so as to lead that only a little effort for the attachment of the material rejuvenation necessary is.

The solution This object is achieved according to the invention in that the Apply the material rejuvenation in the glass plate in its shaping from the molten state he follows.

in the method according to the invention the attachment of the material taper occurs simultaneously with the Shaping the glass plate in one step with the same Shaping tool, which in a simple way without lengthening the cycle time, the attachment of the material taper is made possible.

This advantage is given in particular in a method in which the shaping of the glass plate and the shaping of the Materialverjün Supply by rolling a glass ribbon takes place. By a simple shaping in the rollers, material rejuvenation can then be realized in a simple way.

Around To be able to perform the deformation by gravity lowering, the glass must at least in the rejuvenated Subsections subsequently at least be reheated to its softening temperature.

This can be realized for example by a method in which the reheating a short-wave IR radiation takes place.

The Production of glass ceramic plates with shaped partial areas from those with rejuvenations provided glass plates is advantageously carried out by a method in the reheating and Gravity lowering in the course of the ceramization of the glass plate too a glass ceramic plate takes place.

The for the Ceramifying necessary thermal treatment can then be done simultaneously to reheat the areas to be reshaped, creating energy and a Manufacturing step can be saved.

The material tapers can be formed differently. In the majority of cases comes a method of use in which the material rejuvenation groove-like or is formed groove-like. Such a material rejuvenation is typically the vast majority Requirements in the deformation just.

It Also, a method may be used in which the material rejuvenation with over their Width is steadily increasing in different depths. Such a material rejuvenation Fulfills typically the best form the Umformanforderung when Hochwölben of Bohrrändern or breakthroughs.

is a big area Preferably, a method is used, in which the material rejuvenation flat is formed, and in particular thereby over the entire surface of the reshaping Part of the glass surface extends.

The The invention further relates to a glass ceramic plate with a partial Forming by gravity lowering in at least one section, which is characterized in that the glass or glass ceramic plate in the field of forming a in the shaping of the glass plate in the molten one State has attached material taper.

A Such glass / glass ceramic plate is preferably used as a cooking surface for hobs or as a chimney visor. But also a use as a glass baking dish is possible.

Based of illustrated in the drawings embodiments of transformed cooktops and chimney windows, the invention will be described in detail.

It demonstrate:

1 in four parts of the figure AD, the production steps of a glass ceramic plate for a cooking surface with a bent-up rear portion (figure part D), starting from a green glass plate with a material taper in the reshaping area (Figure Part A) and deformation by gravity reduction targeted in the tapered region during the ceramization (Figure B and parts C),

2 in two figure parts A, B corresponding to the manufacturing stages of a glass ceramic plate 1 , but with forward sloping bending edge,

3 in three figure parts AD, the manufacturing stages of a glass ceramic plate for cooking surfaces or chimney vision with two mutually downwardly extending bending edges (Figure B) or with two oppositely bent edges (Figure C part), starting from a green glass plate with two tapers (Figure A),

4 in three figure parts A, B, C, the manufacturing steps of a glass ceramic plate for a cooking surface with a partial bulge in the rear region of the cooking surface,

5 in four figure parts AD manufacturing steps for an alternative production of a cooking surface with a partial bulge in the rear accordingly 4C .

6 in four parts of the figure AD, the production steps of a glass-ceramic cooking surface for gas hobs with boreholes, which are bulged at the edge, for receiving the gas burners,

7 in four parts of the figure AD, the production steps of a glass-ceramic plate with a central oval, high-arched aperture and smaller, highly curved holes with two variants of the formation of the bulges,

8th in two parts of the figure A, B the production steps of a glass-ceramic plate with a taper applied on the cooking surface side,

9 in two figure parts A, B, the manufacturing stages of a glass ceramic plate with on all four Be lowered edge areas,

10 in two figure parts A, B, the manufacturing stages of a glass ceramic plate with a two-stage plateau, and

11 in two figure parts A, B, the manufacturing steps of a glass-ceramic plate with a tableau-like elevation in the corner,

12 in two figure parts A, B, the manufacturing stages of a glass ceramic plate for a fireplace visor with angled on both sides to the fireplace areas, starting from a green glass plate with the living area facing tapers in the deformed area,

13 in two parts of the figure A, B, the manufacturing stages of a fireplace visor with a central spherical shape, and

14 in two parts of the figure A, B, an alternative manufacturing stages of fireplace fireplace after 13B , starting from a green glass pane with a flat taper in the area to be formed.

By the invention makes it possible, in particular, to provide glass ceramic plates for cooking surfaces, formed in partial areas of the cooking level up or down and can be inexpensively manufactured with high flexibility by: the starting material, the prefabricated green glass plate, in the to be deformed Areas rejuvenated is. These targeted incorporated material dilutions support the Shaping process by simple gravity lowering during the thermal ceramization process.

The 1 shows an example of a deformation in a cooking surface, in which the rear area to be bent up.

In the figure part A is a prefabricated green glass plate 1 with indicated cooking zones 2 shown. In this green glass plate 1 is in the back area 1b parallel to the rear edge 1a running, a material rejuvenation 3 introduced, preferably in the course of rolling the green glass plate. The residual thickness of the glass plate in the tapered region is, for example, in the range of 2-4 mm with a total plate thickness in the range of 4-6 mm.

In the course of the ceramization of the green glass plate 1 This is, as shown in the figure part B, on a support bar 4 with the taper down. When ceramizing the glass plate 1 reheated above the glass softening point, causing the glass plate 1 specifically in the rejuvenated area 3 while remaining a "residual rejuvenation 3 ' lowered only by gravity, with a high degree of deformation. This condition is shown in FIG.

The transformed, ceramized end product 1' with upturned rear area 1'b is shown in the figure part D.

In 2 are in two parts of the figure A, B, the manufacturing stages of a glass ceramic plate 1' corresponding 1 shown, however, in the front area 1'd a bending edge sloping forward 1'c having.

Starting from a green glass plate 1 with a material rejuvenation 3 in the front area 1d with final edge 1c (Part A) is by gravity lowering during the ceramizing analogous to the figure parts 1B and 1C a glass ceramic plate 1' , with sloping bending edge 1'c . 1'd produced (Figure Part B).

In 3 in three parts of the figure AC are the production steps of a glass-ceramic plate 1' represented according to the 1 and 2 both a rear area 1'b as well as a front, sloping area 1'd having.

Starting from a green glass plate 1 with two corresponding material tapers 3 in the front and rear area (figure part A). Is by gravity counter during the Keramisierens analog parts of the figure 1B . 1C either a glass ceramic plate 1' with both rear and front sloping bending edge 1'a . 1'b respectively. 1'c . 1'd (Figure part B) or a glass ceramic plate 1' with rear bent area 1'a . 1'b and front sloping bending edge, 1'c . 1'd produced (figure part C).

The 4 shows in three parts of the figure AC the production steps of a glass ceramic plate 1' with a partial bulge 1'E in the rear of the cooking surface (Figure C part). The associated green glass plate 1 has, as the figure part B in conjunction with the cross-sectional view of the figure part A, a curvy taper 3 in the bulging area. The curvy, partial bulge 1'E can be formed by a corresponding pad of support wedges in the gravity lowering during the ceramization. The bulge 1'E can be used advantageously for ventilation of gas cooking appliances.

The 5 shows in four parts of the figure AD the manufacturing stages one 4 alternative manufacturing method for producing a cooking surface with partial bulge in the rear area. Starting product is a double green glass plate, the two cooking surfaces 1 equivalent. It has in the area of the later separation (impact area) of the two chef make an oval rejuvenation 3 (Figure part A). This double green glass plate is during the ceramizing process by resting on a dome-like pad in the oval tapered area 3 correspondingly dome-like in this area ( 1e ' ) (Figure parts B, C). Subsequently, the double plate is separated in the joint area and there are two cooking surfaces 1' with half partial bulges 1'E ,

6 shows in four parts of the figure AC manufacturing stages of a glass ceramic surface for gas hobs with holes that have a raised overflow edge.

The figure part A with the associated cross-sectional view in part B shows a green glass plate 1 with holes 2 whose lower edges rejuvenate 3 exhibit. By lining up adapted support rings under the drill edges they bulge during the ceramization with a small radius, ie with a high degree of deformation on. The figure part C with the cross-sectional view of Part D shows schematically the gas cooking surface 1' in the deformed state. The holes 2 serve to accommodate the atmospheric gas burner, with the bulging edge 2 ' provides overflow protection against the ingress of overflowing food or cleaning liquids in the interior of the gas hob.

The 7 shows in four parts of the figure AD the manufacturing stages of a glass ceramic plate 1' with an oval breakthrough 4 and smaller holes 5 , for example, for receiving switching knobs. The figure part A shows the corresponding green glass plate 1 with rejuvenations 3 for the breakthrough 4 and the smaller holes 5 , By underlaying appropriately designed support rings during the ceramization, the edges of the opening and the holes are raised by gravity. The figure part B shows the finished cooking surface 1' with the established bore areas 4 ' . 5 ' ,

For the formation of bulges in 7 Different variants are possible (which also apply to the other embodiments), two of which are shown in the figure parts C and D.

In the variant in part C, the rejuvenation 3 formed by the plate thickness to the edge of the bore 5 or breakthrough 4 steadily decreasing. The high vaulted edge 4 ' respectively. 5 ' then has a decreasing wall thickness. For reasons of strength, however, it may be advantageous to leave the direct edge region of the drill edge or breakthrough in the initial thickness. In this case, as shown in the figure part D, in the directly adjacent region of the green glass plate, the taper 3 be formed so as to realize the same edge strength nevertheless a shaping process by gravity.

The 8th shows in two parts of the figure A, B, the manufacturing stages of a glass ceramic plate 1' with rear bent edge 1'a . 1'b corresponding 1 , but with on the top of the green glass plate 1 (Part A) shaped rejuvenation 3 ,

For aesthetic or functional reasons, it can be useful, the rejuvenation 3 on the top of the cooking surface. Be it to additionally create a defined transition or just for aesthetic reasons. Also in this case, the transformation according to gravity lowering is just as possible. The figure part B shows the converted by gravity finished cooking surface 1' ,

The 9 shows in two parts of the figure A, B, the manufacturing stages of a glass ceramic cooking surface 1' with peripherally lowered edge areas 1'f , Starting material is the green glass plate 1 to 9A with the corresponding cross-sectional views, the corner areas cut out 1g has and thus four lowerable edge areas 1f defined, to which a circumferential rejuvenation 3 assigned. During the ceramization lies the green glass plate 1 on a rectangular plateau, so that the tapered protruding edges 1f can sink during the ceramization and so a cooking surface 1' with peripherally lowered edge areas 1'f can train.

These ceramic cooking surface is in the figure part B with the associated cross-sectional views shown.

The 10 shows in two parts of the figure A, B, the manufacturing stages of a glass-ceramic cooking surface with a stepped plateau. According to the figure part A has the associated output green glass plate 1 two at a narrow distance parallel to each other formed tapers 3 on, so that here during the ceramization two bending areas arise, resulting in a corresponding design of the base plate during the ceramizing and gravity lowering a plateau 6 according to figure part B can train. It is also conceivable to introduce further tapering areas, according to the desired shape of the cooking surface.

The 11 shows in two parts of the figure A, B, the manufacturing stages of a glass ceramic cooking surface 1' with a tableau-like elevation 7 in the corner of the cooking surface (Figure Part B). by a corresponding straight-line or contoured rejuvenation 3 the exit green glass panel 1 can be realized (figure part A).

The in the 1 - 11 deformed glass ceramic plates shown have been described in terms of their application as cooking surfaces.

As already stated at the outset, deformed glass-ceramic plates are also used as fireplace viewing windows. For example, the glass ceramic plate is after 3B suitable for use as fireplace visor. In installation position are the two, then vertically extending areas 1'b and 1'd Angled sideways towards the chimney.

The 12 shows in two parts of the figure A, B fireplace view 8th' corresponding 3B , but with the difference that the tapered area 3 facing the living area. This embodiment may be advantageous for design reasons.

The 13 shows in two parts of the figure A, B with associated cross-sectional views of a glass ceramic chimney panel 9 ' with a spherical shape 10 in the middle area. This is done in the original green glass plate 9 (Figure part A) is a circumferential annular area 3 tapered trained. Within this range, the chimney panel lies on a domhaft formed base during ceramization. During the ceramization, this domed bulge can then be transmitted to the chimney pane by means of gravity sinking.

The 14 shows in two parts of the figure A, B with associated cross-sectional views of an alternative production of the spherically deformed chimney panel after 13B , In the alternative production is from a green glass plate 9 assumed, in which the entire spherical area 3 is formed tapered, resulting in the domhafte training 10 the center area even easier to realize.

The thus deformed lens shows the figure B.

In addition to other designs, the chimney panel can also according to the representation in 9 , ie be formed with bent on all four sides areas.

Claims (11)

Method for partially reshaping a glass plate in at least one predetermined subregion by gravity lowering in the at least partially reheated glass plate, wherein in the glass plate before the partial forming in the predetermined portion corresponding to its nominal contour a material taper is attached, characterized in that the attachment of the material taper in the glass plate is made in the shaping of the molten state. The method of claim 1, wherein the shaping the glass plate and the shaping of the material rejuvenation by Roll a glass band later is cut into glass plates takes place. The method of claim 1 or 2, wherein the reheating to execution the gravity is lowered by a short-wave IR radiation. The method of claim 1 or 2, wherein the reheating and Gravity lowering in the course of the ceramization of the glass plate too a glass ceramic plate takes place. Method according to one of claims 1 to 4, wherein the material taper groove-like or is formed groove-like. Method according to one of claims 1 to 4, wherein the material taper with over their Width is steadily increasing in different depths. Method according to one of claims 1 to 4, wherein the material taper is formed flat. The method of claim 7, wherein the material taper over the the whole area the area to be formed is formed extending. Glass or glass ceramic plate with a partial deformation by gravity lowering in at least one subregion, characterized in that the glass or glass ceramic plate ( 1 . 1'; 8th . 8th'; 9 . 9 ' ) in the region of the forming a material in the form of the glass plate in the molten state attached material taper ( 3 ' ) having. Use of the glass or glass ceramic plate according to Claim 9, as a cooking surface for hobs or Fireplace panels. Use of the glass or glass ceramic plate according to Claim 9 as a glass baking tray.