DE20304692U1 - Glasses, in particular watch glasses, with inserted stones, in particular precious stones, semi-precious stones and / or synthetic stones - Google Patents

Description

POSTAL ADDRESS: DR. BRICH NBUGGBAUBR ^{b0RO; 80331} MONCHEM

or. &egr;. NEUGEBAUER Patent Attorney Zweibrockenstrasse

PO BOX 2Hi 101 BUHOPBAN PATENT ATTORNBV D-80058 MÖNCHEN ZUOEU8SEN BBIM EUROPEAN PATENT OFFICE

March 24, 2003

Michael Bonke 94469 Deggendorf

1G-4643

Glasses, especially watch glasses, with set stones/

in particular precious stones, semi-precious stones and/or

synthetic stones

Description

The present invention relates to glasses, in particular watch glasses, with inserted stones, preferably in the form of gemstones, in particular precious stones, semi-precious stones and/or synthetic stones.

The object of the present invention is to create glasses, in particular watch glasses, which have an attractively designed integrated dial or an attractively designed integrated time scale and are used, for example, for installation in a wristwatch or pocket watch.

This object is achieved according to the invention by a glass, in particular in the form of a watch glass for installation in a wristwatch or pocket watch with an integrated dial or an integrated time scale, wherein the dial or the time scale comprises one, four or twelve or more stones, preferably in the form of diamonds, in particular

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BANK DETAILS: AND (069) 29 2561 *** Tel.: +49 21 77 77 90 · Tel.: +49 21 77 77 90 · Tel.: +49 21 77 77 90 · Tel.: +49 21 77 77 90 · Tel.: +49 21 77 77 90 TELEFAX <0 89) 29 25 G2 BAVAHfAPATENT MOMCHEN SS19-603 (BLZ 700100 60) ACCOUNT 565 500 (BLZ 700 202 70)

special diamonds and/or semi-precious stones and/or synthetic stones and preferably in different sizes, stone types and/or colours.

According to the invention, the stones can be set directly into the glass, preferably with the interposition of a solder glass section.

Alternatively, according to the invention, the stones can be set in the glass by means of gold frames, which preferably have recesses and/or constrictions and/or projections or widenings on their outer surface adjacent to the glass in order to improve the hold of the frames in the glass.

According to the invention, it can be advantageous to use gold frames in the form of a funnel which is designed in such a way and in which a stone, in particular a diamond, is set in such a way that it is essentially only in contact with the funnel in the region of its girdle and there is an air gap between the lower part of the diamond and the funnel, wherein the funnel can have a foot part extending into the glass plate for its anchoring with a constricted upper section and a widened lower section.

According to the invention, the stones can alternatively be fixed in the glass by means of an adhesive, whereby instead of glass or in combination with glass, plexiglass, plastic plates and/or crystal plates can be used.

A vacuum furnace can be used to produce the glasses, in which a glass is connected to the stone or diamond and the furnace is flooded with nitrogen. The vacuum furnace is used as a work station to set the stone or diamond in the glass. The vacuum furnace is first evacuated and then flooded with nitrogen before heating. The vacuum furnace is preferably evacuated again after the first evacuation and flooding and flooded again with nitrogen. Preferably the entire vacuum furnace, including the vacuum pump, is also flooded with nitrogen during the heating process so that the vacuum pump does not suck in fresh air but nitrogen and a double nitrogen cycle is achieved with total removal of the oxygen in the air so that the stone or diamond remains undamaged during the heating process.

A section of solder glass can be inserted into a glass plate at the points where a diamond is to be set. This section is provided with a stepped hole, preferably not through, into which a diamond is inserted. The diamond is then heated to a temperature of between approximately and 750 degrees Celsius, preferably in a vacuum furnace with a double nitrogen circuit.

Basically, there are two different methods for setting stones in glass:

Firstly, the setting of the stone with a gold border, whereby instead of gold, another suitable material can be used. This means that the stone is set in a material such as gold, and this material is

then placed into the glass together with the stone. A second method consists of setting the stone without any surrounding material, directly into the glass.

The following difficulties arise when setting stones in glass:

Glass has different expansion coefficients depending on its composition. For example, float glass has an expansion coefficient of around 83 &khgr; 10-7, drawn glass around 93 &khgr; 10-7, borosilicate glass 34 &khgr; 10-7, and quartz glass has even lower expansion coefficients.

Diamond has a coefficient of expansion of approximately 8 x 10-7 at normal temperature. The hotter the diamond, the higher its coefficient of expansion becomes. At 1000 degrees Celsius, the coefficient of expansion is approximately 40 x 10-7.

Not only is the coefficient of expansion of diamond different from that of glass, but the change in the coefficient of expansion at different temperatures is also not analogous to that of glass.

In order to not only glue the stone into the glass, but to be able to set it properly, the glass must be heated to a temperature at which it is at least soft. This temperature is around 750 degrees Celsius. With quartz glass, the temperature is much higher, up to 1300 degrees Celsius.

If the stone is now inserted into the glass at high temperature, then the glass and diamond (or any other stone) will contract differently when cooling.

This creates tension where the two materials touch. This normally causes the glass to crack.

Another problem is that the diamond (pure carbon) graphitizes or even burns at higher temperatures on the surface. The same or similar damage also occurs with other gemstones.

A third problem is that the effect of the diamond or gemstone is based on the fact that the light is directed back upwards by reflection (preferably total reflection) on the underside of the stone and thus falls back into the viewer's eye. The sparkle of the stone is based on these reflections of light within the diamond (gemstone).

The reflection (particularly the total reflection) occurs due to the different optical densities of the gemstone and air. The refractive index of the stone (the highest of all for diamonds = 2.54) determines the angular size of the total reflection angle (65° for diamonds).

The greater the difference in the optical density of the two optical media, the greater the angle of total reflection, the better the light output of the reflected light and thus the better the effect of the gemstone (sparkle, fire, dispersion of light, etc.). In places where the diamond or gemstone directly touches the glass, there is a completely different difference in optical density than between diamond and air. The difference

The difference is much smaller. The light is therefore not reflected but is directed into the glass. This causes the stone to lose its fire and brilliance. For reasons of optical effect, contact between glass and diamond must be avoided as much as possible.

The problem of burning the gemstone can be avoided by using a vacuum furnace in which the glass is bonded to the diamond and which is flooded with nitrogen. It is important that no residual air remains in the furnace and mixes with the nitrogen, because even a very small amount of atmospheric oxygen leads to changes in the surface of the diamond during the melting process of the glass. According to the invention, a vacuum furnace is therefore used as a workstation for setting the stone in the glass. Before heating the furnace, the furnace is first evacuated and then flooded with nitrogen.

However, this never creates a complete vacuum. If a residual pressure of one thousandth of a bar remains during evacuation, then the 0.1 percent original air content that is then mixed with the nitrogen is enough to still damage the stone. With normal vacuum pumps, you can remove up to about 1 percent of residual air, but hardly more.

So after the first evacuation and flooding, the nitrogen-air mixture is evacuated again and the furnace is flooded with nitrogen again. Theoretically, there should then be a residual proportion of air of 1 percent, i.e. one ten thousandth of a percent.

But this is only theoretical, because if a vacuum pump is able to maintain a vacuum of 1 percent, then this means that it sucks out as much air as re-enters the vacuum through leaks (often through the pump itself). It therefore maintains equilibrium at around 1 percent pressure (or air). However, the air that re-enters changes the air-nitrogen mixture to the detriment of the nitrogen. So if the furnace chamber is evacuated several times and flooded with nitrogen again in order to maintain a residual proportion of air of a fraction of 1 percent, then this low oxygen proportion does not remain the same while the vacuum pump is running, but slowly shifts back to the one percent.

That is why the entire vacuum furnace, including the vacuum pump, is surrounded with nitrogen during the heating process, or all potentially leaky spots in the vacuum body are also flooded with nitrogen. In this case, the vacuum pump does not suck in fresh air, but nitrogen.

Only with this double nitrogen cycle can one achieve such a total removal of atmospheric oxygen that the diamond (or gemstone) survives the heating process undamaged.

In the setting of diamonds and other stones according to the invention, as described in more detail in particular in connection with Figs. 3a to 11b, at least the heating is therefore preferably carried out in a vacuum furnace with a double nitrogen circuit.

When you buy nitrogen, there are different purities of nitrogen. The normal purity used for technical purposes is not sufficient for the purpose of the invention; you have to use specially pure nitrogen.

With a diamond we have three zones that have different significance for the guidance of light: the upper part, the girdle and the lower part.

The upper part has the task of letting the light into the stone. The light is let in through the panel relatively undiffracted and is diffracted by the upper part facets, which lie around the panel, so that it enters at an ideal angle.

The top part also has the task of letting the reflected light out of the stone again. The light is bent by the panel or the top facets in such a way that it ultimately falls back to where it originally came from. This gives the stone the greatest effect for the viewer.

The lower part of the stone has the task of reflecting the light that has entered through the upper part in such a way that it exits through the upper part again with as little light loss as possible and, what's more, exits at the correct angle of reflection.

·

The girdle (the connection between the upper and lower parts) usually only has technical significance and no optical significance. The girdle is a band around the stone (like a kind of belt) which is perpendicular to the table. If the upper and lower parts met without a girdle, a razor-sharp edge with an acute angle would be created. This would lead to breakages and the stone would always be damaged. For this reason, a girdle of around 1 to 3 percent of the total height of the stone is created around the stone with transition surfaces perpendicular to the table. Light that hits the girdle from the inside is normally lost for the diamond's play of light. It escapes to the outside, or is reflected in such a way that it does not exit through the upper part at the correct angle. If the diamond meets the glass at the girdle, this has no significance for the optical effect of the diamond.

According to the invention, a diamond is preferably set in the glass in such a way that it sits in the glass only with the girdle or the immediately adjacent areas of the upper and lower parts, in order to preserve the optical qualities of the stone. In addition, care should be taken to ensure that the stone is set in such a way that no liquids, skin cream or other contaminants penetrate into the "air area" around the lower part of the stone. Otherwise, the stone will also lose its full optical effect. The stone should therefore be set in such a way that inaccessible areas of the "air area" surrounding the lower part are sealed watertight.

There are several ways to set diamonds (or other gemstones) in glass, even though both materials have different coefficients of expansion. One possibility is to use a material that is either elastic or flexible in its expansion, so that it bridges the different coefficients. One such material is, for example, fine gold, which adapts to different coefficients of expansion when it is placed between glass and diamond.

Gold has a coefficient of expansion of 140 x 10-7, which is greater than that of glass: but because of its softness, this does not matter. You can melt gold together with glass without the glass cracking.

There are two possible types of gold to use as a setting for a diamond. Depending on your design requirements, you can use yellow gold, fine gold, or white gold.

For yellow gold, pure gold is the best material. It bonds most easily with glass. For white gold, an alloy of 85 parts by weight of gold and 15 parts by weight of palladium is most suitable.

If you want to set the diamond directly into the glass without a setting edge for design reasons, you can use "solder glass" as a buffer material. This is a glass that can bridge the expansion coefficient between normal glass and all kinds of materials (e.g. ceramic).

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Another method of preventing stress cracks in the glass is to simply separate the diamond from the glass. A separating agent can be used to prevent the diamond and glass from growing together during the melting process. However, the separating agent usually changes the optical qualities of the diamond, or is visible even if it is not transparent. However, it can be removed again after the melting process. This means that the diamond sits somewhat loosely in the setting. Depending on the design of the object, this does not have to be a problem. However, the diamond can also be fixed again after the glass has been melted, e.g. with a fine silicone adhesive that runs along the girdle and connects the stone to the glass at this point. This is also a good way of preventing liquids or creams from penetrating the "air zone" of the diamond setting.

The invention is explained in more detail below using schematic drawings of exemplary embodiments. It shows:

Fig. 1a is a schematic plan view of a first embodiment of a watch glass according to the invention;

Fig. 1b is a schematic section along the line b-b through the watch glass according to Fig. la;

Fig. 2a is a schematic plan view of a second embodiment of a

watch glass;

Fig. 2b is a schematically drawn section along the line b-b of Fig. 2a;

Fig. 3a is a schematic section through a glass plate with an inserted solder glass section having a stepped bore into which a diamond is inserted, on an enlarged scale, before heating;

Fig. 3b a section analogous to Fig. 3a through the glass plate and the diamond after heating to a temperature between about 400 and 750 degrees Celsius, adapted to the melting temperature of the solder glass, which, depending on its composition, is between 400 and 700 degrees Celsius;

Fig. 4a is a section similar to Fig. 3a through a glass plate with a stepped hole into which a diamond with a gold frame is inserted;

Fig. 4b a section analogous to Fig. 4a through the glass plate and the diamond after heating to about 750 degrees Celsius;

Fig. 5a is a section similar to Fig. 4a through a glass plate with a continuous stepped hole into which a diamond with a gold frame is inserted, the stepped hole being covered at the top with an additional cover glass plate;

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Fig. 5b a section analogous to Fig. 5a through the glass plate and the diamond after heating to about 750 degrees Celsius;

Fig. 6a is a section similar to Fig. 5a through a glass plate with a non-continuous stepped bore into which a diamond with a gold frame is inserted, the upper opening of the stepped bore being covered with a cover glass plate;

Fig. 6b a section analogous to Fig. 6a through the glass plates and the diamond after heating to about 750 degrees Celsius;

Fig. 7a is a section similar to Fig. 6a through a glass plate with a continuous stepped bore into which a diamond with a gold frame is inserted upside down, i.e. with its upper part facing downwards, whereby the upper opening of the stepped bore, which faces the lower part of the diamond, is covered with a cover glass plate;

Fig. 7b a section analogous to Fig. 7a after heating to about 750 degrees Celsius;

Fig. 7c is a section corresponding to the section in Fig. 7b after grinding off the part of the glass plate which protrudes downwards over the upper part or table of the diamond in Fig. 7b and the subsequent turning of the glass plate;

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Fig. 8a, 8b and 8c each show a section similar to Fig. 7a, 7b and 7c respectively of a modified embodiment in which the diamond does not have a gold frame but is provided with a separating agent in the region of its girdle;

Fig. 9a is a section similar to Fig. 4a through a glass plate with a non-continuous stepped bore into which a diamond is inserted, but which does not have a gold frame, a separating agent being provided between the diamond and the wall of the stepped bore;

Fig. 9b a section analogous to Fig. 9a after heating to about 750 degrees Celsius;

Fig. 10a is a section through a glass plate similar to Fig. 9a, but with the stepped bore covered at its upper opening with a cover glass plate which is designed as a collecting lens in the region of the stepped bore;

Fig. 10b shows a section analogous to Fig. 10a after heating to about 750 degrees Celsius;

Fig. 11a is a section through a glass plate similar to Fig. 4a with a non-continuous cylinder bore that widens upwards to form a funnel into which a funnel-shaped gold frame with a diamond is inserted; and

·

Fig. lib a section analogous to Fig. 11a after heating to about 750 degrees Celsius.

Fig. 1a shows a top view of a first embodiment of a glass according to the invention, which is designed as a watch glass 10 with an integrated dial or an integrated time scale, which has four stones 18 in the form of diamonds that are set directly in the watch glass 10. Instead of the four diamonds 18, other diamonds and/or semi-precious stones and/or synthetic stones of uniform size, color and type of stone or of different sizes, colors and types of stone can be used. One, four or twelve or even more stones are used for a dial or a time scale. As can be seen from Fig. 1b, the stones 18 are set directly in the watch glass 10. It can also be seen from Fig. 1b that the watch glass 10 has an edge 12 and in the area of the lower part of the stones 18 there is a recess 15b as an air area between the glass and the diamond.

Fig. 2a shows a top view of a second embodiment of the watch glass according to the invention, which is designed similarly to Fig. 1a, wherein the stones 28 each have a stone setting in the form of a gold frame 27 and are incorporated with this stone setting into the watch glass 20. As can be seen from Fig. 2b, the watch glass 20 has a recess 25b below the stones 28 and is provided with an edge 22.

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Fig. 3a and 3b show a possibility according to the invention for directly setting a diamond 18 in a glass plate 10 with an inserted solder glass section 11 which has a stepped bore 14a, 15a with an annular shoulder 16, the diamond 18 being introduced into the stepped bore 14a, 15a from above. The arrangement of glass plate 10, 11 and diamond 18 are heated to a temperature between about 400 and 750 degrees Celsius, adapted to the melting temperature of the solder glass, which, depending on its composition, is between 400 and 700 degrees Celsius. After this heating, a uniform glass plate 10, 11 is obtained, i.e. the solder glass section 11 is no longer recognizable and the diamond 18 is firmly melted into the glass with its girdle 19.

Fig. 4a and 4b show a method for setting a diamond 28 by means of a gold frame 27 in a stepped bore 24a, 25a of a glass plate 20, wherein the stepped bore is designed such that the diamond 28 with its gold frame 27 comes to rest against the ring shoulder 26. After heating to about 750 degrees Celsius, a stable, firm mount of the gold frame and the diamond 28 set by means of the gold frame in the glass plate 20 is obtained, wherein the diamond 28 remains separated from the glass, as can be seen from Fig. 4b.

Fig. 5a shows a section through a glass plate 30b with a continuous stepped bore 34a, 35a into which a diamond 38 with a gold frame 37 is inserted, the stepped bore being provided at the top with an additional cover glass.

plate 31. After heating to about 750 degrees Celsius, the glass plates 30a and 31 are fused to form a glass plate 30b, as can be seen from Fig. 5b.

Fig. 6a shows a section similar to Fig. 5a through a glass plate 30c with a non-continuous stepped bore 34a, 35c into which a diamond 38 with a gold frame 37 is inserted, the upper opening of the stepped bore being covered with a cover glass plate 31. After heating to about 750 degrees Celsius, the glass plates 31 and 30c are fused to form a glass plate 30d, as can be seen from Fig. 6b, and the diamond 38 is fused in a closed cavity 34b, 35d.

Fig. 7a shows a section similar to Fig. 6a through a glass plate 30e with a continuous stepped bore 34e, 35e into which a diamond 38 with gold frame 37 is turned upside down, i.e. with its upper part facing downwards, whereby the upper opening of the stepped bore 34e, 35e, which faces the lower part of the diamond 38, is covered with a cover glass plate 31. As can be seen from Fig. 7b, after heating to about 750 degrees Celsius, a uniform glass plate 30f is obtained. Then the part of the glass plate 30f which protrudes downwards over the line 33 in Fig. 7b is ground down so that the surface of the glass plate is flush with the surface, i.e. the table of the diamond 38, and after turning, the glass plate 30g shown in Fig. 7c is obtained.

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Fig. 8a, 8b and 8c each show a section similar to Fig. 7a, 7b and 7c of a modified process in which the diamond 38 does not have a gold frame, but is provided in the area of its girdle 39 with a separating agent 40, which is preferably applied as a paste, which can consist, for example, of a mixture of finely ground graphite powder and spirit or fine-grained kaolin and water.

After the paste has dried, it is heated to about 750 degrees Celsius and, as shown in Fig. 8b, a uniform glass plate 3Of is obtained, which is ground down to line 33. The separating agent is then removed by washing. However, even after the separating agent has been removed, the diamond is held in the cavity 35f, albeit loosely, since the diameter of the bore 34e was chosen to be somewhat smaller than the outer diameter of the diamond 38, as can be seen from Fig. 8a.

According to the invention, after the removal of the separating agent, the diamond can be fixed again by an adhesive 41, preferably a silicone adhesive, which runs along the girdle, whereby the ventilation area 35f is simultaneously protected against the penetration of liquids and creams or the like.

Fig.9a shows a section through a somewhat thicker glass plate 30h with a deep but not continuous stepped bore 34h, 35h, into which a diamond coated in the lower and middle area with a separating paste 40 is inserted, preferably with a precise fit from above.

After the paste has dried, it is heated to about 750 degrees Celsius, whereby the glass has a tendency to enclose the diamond 38. After cooling and removal of the release agent, the diamond 38 sits loosely in the cavity 35i, which represents an air area between the diamond and the glass, and can be fixed by means of an adhesive 41.

Fig. 10a shows a section through a glass plate 43 with a continuous stepped bore, the lower part 47 of which has a smaller diameter and the upper part 48 of which has a larger diameter than the diamond 38, the glass being coated with a separating paste 40 in the area of the ring shoulder 49 and the diamond 38 then being introduced into the bore 48 from above. The bore 48 is then covered by a glass plate 44, into which a collecting lens is integrated in the area of the bore 48 above the diamond 38 as a convex bulge 45, which enhances the optical effect of the diamond.

When heated to about 750 degrees Celsius, the glass plates 43 and 44 are bonded together to form a glass plate 43g, as shown in Fig. 10b, preferably by fusing, which takes place in a vacuum oven, preferably with a double nitrogen circuit, in order to avoid air or gas bubbles. After the separating agent has been removed, the diamond 38 can be fixed in the cavity 48g, 47g by means of an adhesive 41. Fig. 11a shows a section through a glass plate 30j with a non-continuous two-part bore, the lower part 55 of which is designed as a cylinder bore with a smaller diameter and the upper part 56 of which

funnel-shaped to a larger diameter
and a funnel-shaped gold frame 50, in which
a diamond 38 is set in such a way that it is essentially only in contact with the funnel 51 of the gold frame 50 in the area of its girdle 39 and between the lower part
of the diamond 38 and the funnel 51, an air gap 60 is present, whereby the gold frame 50 is a
Cylinder bore 55 of the glass plate 3Oj has a foot part 52, 53 extending into it with a constricted at 52
upper section and a widened lower section
53. When heated to about 750 degrees Celsius, the glass of the glass plate 30k comes into intimate contact with
the gold frame 50 and in particular its foot part 52, 53,
so that a secure anchoring of the gold frame 50 is achieved.

The present invention relates to all individually
or in combination with the features disclosed in the foregoing description, the accompanying drawings and/or the following claims.

Claims (8)

1. Glass, in particular watch glass, characterized by stones, in particular precious stones, semi-precious stones and/or synthetic stones ( 18 , 28 , 38 ), inserted into the glass ( 10 , 20 ) and arranged in the form of a pattern, in particular a pattern designed as a time scale or dial. 2. Glass according to claim 1, characterized in that it is designed as a watch glass ( 10 , 20 ) for installation in a wristwatch or pocket watch with an integrated dial or an integrated time scale, which has one, four or twelve or more stones ( 18 ; 28 ; 38 ), preferably in the form of diamonds, in particular brilliants and/or semi-precious stones and/or synthetic stones and preferably in different sizes, stone types and/or colors. 3. Glass according to claim 1 or 2, characterized in that the stones ( 18 ) are set directly in the glass ( 10 ), preferably with the interposition of a solder glass section ( 11 ). 4. Glass according to claim 1 or 2, characterized in that the stones ( 28 , 38 ) are set in the glass ( 20 , 30a , 30c , 30e , 30j ) by means of a gold frame ( 27 , 37 , 50 ) which preferably has recesses and/or constrictions ( 52 ) and/or projections or widenings ( 53 ) on its outer surface adjacent to the glass. 5. Glass according to claim 4, characterized in that the gold frame ( 50 ) has a funnel ( 51 ) which is designed in such a way and in which a stone, in particular a diamond ( 38 ) is set in such a way that it is in contact with the funnel ( 51 ) essentially only in the region of its girdle ( 39 ) and an air gap ( 60 ) is present between its lower part and the funnel ( 51 ), wherein the gold frame ( 50 ) preferably has a foot part ( 52 , 53 ) extending into the glass plate ( 30 j or 30 k) with a constricted upper section ( 52 ) and a widened lower section ( 53 ). 6. Glass according to one or more of claims 1 to 5, characterized in that the stones or diamonds ( 28 , 38 ) are arranged in stepped bores ( 47 , 48 ) in the glass ( 43 ) and are covered with a glass plate ( 44 ), preferably with converging lenses ( 45 ) integrated therein, wherein the converging lenses ( 45 ) in the glass plate ( 44 ) are each arranged in the region of a stepped bore ( 47 , 48 ) and each above a stone or diamond ( 28 , 38 ). 7. Glass according to claim 1 or 2, characterized in that the stones ( 38 ) are fixed in the glass ( 30 g, 30 i, 43 g) by means of an adhesive ( 41 ). 8. Glass according to one or more of claims 1 to 7, characterized in that it is made of plexiglass, plastic plates and/or crystal plates or of a combination of one or more of these materials with glass.