EP3973362B1 - Timepiece with decorative crystal - Google Patents

Description

The invention relates to a watch glass with a decorative element and to a watch with such a watch glass.

Watch crystals with decorative elements are well known. In particular, the current state of the art offers a wide variety of solutions for arranging decorative elements on the watch crystal. For example, a common method is to attach decorative elements to the watch crystal using a setting.

EP 3 541 225 A1 The disclosure reveals a watch glass comprising a base glass with at least one recess, a cover glass, at least one gemstone which is at least partially arranged in the recess, and a connecting intermediate layer by which the cover glass and the base glass are connected to each other. A portion of the upper part of the gemstone is in direct contact with the intermediate layer.

The present invention is based on the objective of creating a watch glass with a decorative element, wherein the decorative element is securely attached to the watch glass and appears to float.

This problem is solved by a watch crystal with the combination of features of the independent claim. The watch crystal comprises a first crystal, a second crystal, and a decorative element, in particular a gemstone. The first crystal and the second crystal are connected to each other via a bonding interlayer. The first crystal has a through-hole, and the decorative element has a base area. The base area is arranged without a setting in the through-hole of the first crystal and is in direct contact with the bonding interlayer. In other words, the watch crystal does not have a setting by which the decorative element or its base area is held in the hole of the first crystal.

The freestanding arrangement of the decorative element gives the watch glass a special appearance, as the decorative element comes to the forefront in terms of visual appeal and preferably even seems to float in or on the watch glass.

Especially when the first glass is not covered by another glass, the decorative element is directly visible, not through another glass, due to the continuous design of the recess in the first glass. Thus, the decorative element, particularly a gemstone, appears realistic, as some of the light falling on the first glass is reflected. The light hits the decorative element directly and is not attenuated by a glass covering the decorative element.

By using a first and second glass layer connected by a bonding interlayer, a stable watch crystal is created. In particular, the watch crystal is thus designed to be break-resistant as a single unit, since any microcracks that could potentially arise from the formation of the cutouts terminate at the bonding interlayer and are therefore not transmitted to the second glass. This is especially advantageous when the first glass has two or more, for example, twelve, continuous cutouts with corresponding decorative elements. The more cutouts a glass has, the smaller the distance between them, and the more likely it is that microcracks at adjacent cutouts will propagate towards each other and connect due to mechanical stress on the glass, ultimately leading to breakage. With this particular connection, however, the mechanical stress on the first glass when the decorative elements are struck is reduced, as the impact energy is distributed to the second glass via the bonding interlayer and absorbed by it. This prevents adjacent microcracks from connecting, which could otherwise cause the glass to break through.

Furthermore, the bonding intermediate layer can compensate for potential surface deviations of the glasses, resulting in a very stable bond between the glasses.

In particular, due to the absence of a mounting, the base area of the decorative element is in direct contact only with the connecting intermediate layer or only with the connecting intermediate layer and air.

In the context of the present invention, the term "setting" is understood to mean, in particular, a metal setting, for example, a gold setting.

Advantageously, the first glass is arranged on top of the second glass.

The first glass and the second glass are preferably each designed as a glass pane. The first glass and the second glass are preferably bonded together over their entire surface via the connecting intermediate layer.

According to one embodiment, the second glass preferably has no recess that is continuous and, in particular, aligned with the recess of the first glass. It is especially preferred that the second glass is continuous, i.e., that the second glass has no recess. In the latter case, only the first glass has one or more recesses. Several continuous cutouts are provided. This ensures the water resistance of the watch crystal and therefore also of the watch itself.

According to an alternative embodiment, the second glass preferably has a recess, which is particularly continuous. The continuous recess of the first glass (first recess) and the recess of the second glass (second recess) form a watch glass recess.

In particular, the first glass is made of sapphire glass.

The bonding intermediate layer is arranged in particular between the first glass and the second glass, especially between opposite surfaces of the glasses.

Within the scope of the invention, the surface of the first glass facing the second glass can also be referred to as the underside of the first glass. Similarly, within the scope of the invention, the surface of the second glass facing the first glass can also be referred to as the top side of the second glass.

Within the scope of the present invention, the first glass is in particular the glass on which the light first hits when the watch glass is arranged in a watch.

The first glass and the second glass are bonded together by the connecting intermediate layer.

Preferably, the bonding intermediate layer can be formed from an organic or inorganic bonding or adhesive compound or adhesive layer, or from an elastic film (also: composite film, in particular adhesive film). In particular, the bonding intermediate layer can be formed from casting resin. The casting resin can be, for example, a two-component epoxy resin or a UV-curing one-component adhesive.

Preferably, the thickness of the bonding interlayer at the location of the decorative element in the thickness direction of the glass is between 5% and 12%, in particular between 7% and 10%, of the thickness of the watch glass (i.e., the thickness of the arrangement consisting of the first glass, the second glass and the bonding interlayer).

Preferably, the thickness of the bonding intermediate layer at the location of the decorative element in the thickness direction of the glass is between 12% and 22%, in particular between 14% and 20%, of the thickness of the first glass and/or the thickness of the second glass.

Preferably, the bonding intermediate layer has the same thickness at every point between the first glass and the second glass and/or at every point between the first glass and a lateral surface of the decorative element.

The connecting intermediate layer is advantageously transparent.

Furthermore, the bonding interlayer preferably has a refractive index that is equal to or substantially equal to the refractive index of the first glass and/or the second glass. "Substantially equal" in the context of the invention means, in particular, that the refractive indices of the bonding interlayer and the first glass and/or the second glass differ from each other by a maximum of 20%. It is advantageous if the refractive index of the first glass is greater than the refractive index of the bonding interlayer. In particular, the refractive index of the bonding interlayer is 1.4 to 1.6, and more specifically 1.48.

For example, the connecting intermediate layer can be made of an EVA (ethylene-vinyl acetate copolymer) laminating film.

The decorative element is preferably a gemstone, in particular a precious or semi-precious stone, especially a diamond. The gemstone can be natural or synthetic.

Within the scope of the invention, a gemstone is understood to be a polished stone, particularly one with optical properties such as transparency. The gemstone may, in particular, be faceted.

1. 1. Seltenheit
2. 2. Mohshärte (Edelsteinhärte) größer gleich 5, bevorzugt größer gleich 6, besonders bevorzugt größer gleich 7
3. 3. Transparenz
4. 4. Brechungsindex größer gleich 1,56, bevorzugt größer gleich 1,7

Furthermore, within the scope of the invention, a gemstone is understood in particular as a gemstone which meets the following four criteria:

1. 1. Rarity
2. 2. Mohs hardness (gemstone hardness) greater than or equal to 5, preferably greater than or equal to 6, particularly preferably greater than or equal to 7
3. 3. Transparency
4. 4. Refractive index greater than or equal to 1.56, preferably greater than or equal to 1.7

Diamonds, rubies, sapphires, and emeralds are particularly important gemstones. Specifically, diamonds have a Mohs hardness of 10 and sapphires a Mohs hardness of 9. Furthermore, diamonds have a refractive index of 2.4.

The decorative element is particularly preferably a gemstone or precious stone with a Mohs hardness of at least 8, preferably at least 9, and/or a refractive index of at least 1.7.

In the present invention, a glass component is not considered a gemstone (semi-precious stone, precious stone, or other gemstone) due to its chemical composition and structure, even if the glass component consists of a material (starting material) that, in its raw state, is classified as a gemstone (semi-precious stone, precious stone, or other gemstone). The glass component may, for example, be quartz glass, which is not considered a gemstone, even though quartz (starting material) is a gemstone.

According to an alternative advantageous embodiment of the watch glass, the decorative element can be a metal inlay, for example a gold inlay.

If the watch glass has a number of decorative elements, any combination of semi-precious stones, precious stones, other gemstones and metal inlays is possible.

Preferably, the base region has an end face. The end face of the base region is preferably at least partially, and in particular completely, in direct contact with the connecting intermediate layer.

In particular, only the front face of the base area can be in direct contact with the connecting intermediate layer.

The end face of the base area is, in particular, the side of the decorative element that faces the second glass and is specifically perpendicular to one of the thickness directions of the glass. The thickness direction of the glass is a direction perpendicular to the glass.

Alternatively or additionally to the end face, a circumferential surface of the base region can preferably be in direct contact with the connecting intermediate layer, at least partially, and in particular completely. Partial contact of the circumferential surface with the connecting intermediate layer, within the scope of the invention, means in particular that the circumferential surface of the base region does not contact the connecting intermediate layer over its entire length and/or not completely around, i.e., not over 360 degrees. Conversely, complete contact between the circumferential surface of the base region and the connecting intermediate layer means that the circumferential surface of the base region is in contact with the connecting intermediate layer over its entire length and over 360 degrees.

It should further be noted that, within the scope of the invention, the connecting intermediate layer is in particular both a connecting material located between the opposing surfaces of the first glass and the second glass, and Connecting material which may be located between the perimeter surface of the base area of the decorative element and the first glass.

Within the scope of the invention, the base region or the end face of the base region can be described as "embedded in the connecting intermediate layer" if both the end face and at least a part of the circumferential surface of the base region are in direct contact with the connecting intermediate layer.

According to one embodiment, the base area of the decorative element is advantageously arranged completely in the recess of the first glass.

In particular, the base area of the decorative element is only located in the recess of the first glass.

Preferably, the base area, in particular the end face, of the decorative element is flush with a surface (underside) of the first glass facing the second glass. Alternatively, the base area of the decorative element can terminate in the recess of the first glass. In the latter case, this means, in particular, that an end area, especially the end face, of the base area is spaced from a surface of the first glass facing the second glass in the thickness direction of the glass. Since the base area does not project into the second glass, it can remain partially or completely invisible from the side. This is possible because, due to the arrangement of the decorative element already described, at least some of the light striking the first glass and refracting at its surface misses the base area and passes under the end area, in particular the end face, of the base area through the second glass. Thus, a watch case can also be compact, or more space can be available for the movement, hands and dial inside the case, since the decorative element does not extend beyond the second glass.

Preferably, the base of the decorative element is shaped like a pin. In particular, the base is cylindrical.

Preferably, the base area of the decorative element has a recess, particularly a circumferential one, especially in a circumferential surface of the base area. Within the scope of the invention, the circumferential surface of the base area can also be referred to as the lateral surface.

In particular, the indentation is completely circumferential, i.e., over 360 degrees.

Preferably, the recess has a depth in a direction perpendicular to the thickness direction of the glass of at least 0.1 mm, preferably at least 0.2 mm, and particularly preferably at least 0.3 mm. In particular, the recess has a constant depth.

The depression is particularly preferably shaped in a ring shape.

The decorative element has an additional area that extends beyond the first glass. The visual impression of the watch glass can therefore be influenced by this additional area of the decorative element.

The decorative element is advantageously formed in one piece.

In particular, the additional area can project beyond the first glass in the thickness direction of the glass and/or in a direction perpendicular to the thickness direction, especially in any direction perpendicular to the thickness direction. In other words, the additional area is advantageously arranged above the first glass or a top surface of the first glass. The phrase "in any direction perpendicular to the thickness direction" means, in particular, that the additional area projects completely around, i.e., over 360 degrees, beyond the recess of the first glass.

Thus, the base area can be visually concealed by the additional area, creating the impression that the decorative element consists solely of the additional area. At the same time, however, the base area ensures a secure connection between the decorative element and the first pane of glass.

In particular, compared to a decorative element that is attached to and bonded to a glass surface solely via its underside, the decorative element according to the present invention and its described arrangement is advantageous because, in the event of a potential impact to the additional area, the decorative element is fixed in the recess of the first glass surface by its base area, and the impact energy is distributed to the second glass surface via the bonding intermediate layer. In contrast, the connection of a decorative element that is only bonded to the top surface of the glass surface can relatively easily detach due to mechanical stress on the decorative element and/or over time.

Preferably, the additional area is arranged on the first glass or on a top surface of the first glass. This means that a bottom surface of the additional area, facing the first glass, lies on the top surface of the first glass.

Preferably, there is no material bond between the underside of the additional area and a top surface of the first glass. However, it is also possible that the opposing surfaces of the additional area and the first glass are materially bonded to each other.

Preferably, the cross-sectional area of the additional area of the decorative element is larger than the cross-sectional area of the recess on the plane of the top surface of the first glass. In particular, a portion of the additional area, and especially the entire additional area, has a cross-sectional area that is larger than the cross-sectional area of the recess of the first glass on the plane of the top surface of the first glass. The cross-sectional area of the additional area and/or the recess of the first glass is/are, in particular, perpendicular to the thickness direction of the glass.

A ratio of the length of the base area of the decorative element in the thickness direction of the glass to the length of an overhang of the additional area in a direction perpendicular to the thickness direction, in particular to any direction perpendicular to the thickness direction, is chosen such that light reflectable from the base area is totally reflectable at an inner surface of the first glass and/or at least a part of the light entering the first glass does not reach the base area.

In other words, this ratio can preferably be chosen such that at least a portion of the light, in particular all the light that passes through the first glass and strikes the base of the decorative element, is reflected at an angle greater than the angle of total internal reflection of the first glass. Thus, this light is totally reflected at the inner surface of the top of the first glass and cannot escape from the first glass. In other words, due to total internal reflection, this light is reflected back into the first glass. Since this light cannot reach the viewer's eye, the base of the element optically disappears.

Alternatively or additionally, this ratio can preferably be chosen such that a portion of the light passing through the first glass does not reach the base area. Due to the refraction of the light passing through the first glass, the ratio is chosen such that the light is refracted in such a way that it no longer reaches the base area. Thus, the base area is not visible.

In particular, this ratio can be chosen such that all light entering the first glass does not reach the base area.

A particularly preferred ratio is that of the length of the base area of the decorative element in the thickness direction of the glass to the length of any overhang of the additional area in a direction perpendicular to the thickness direction, with a maximum of "2 to 1". With such a ratio, the base area is not visible and the stability of the decorative element is also ensured.

Preferably, the first glass has a higher refractive index than the second glass.

Preferably, the first glass has a refractive index greater than or equal to 1.6, and in particular greater than or equal to 1.7. This allows at least some of the light, especially all light striking the first glass obliquely, to be refracted at its surface in such a way that this light does not reach the base of the decorative element. Thus, the refractive index of the first glass can also contribute to making the base barely visible, or ideally not visible at all, to an observer.

According to a preferred embodiment of the invention, the recess in the first glass has the same cross-section along its entire length. This simplifies the manufacturing of the recess in the first glass. For example, the recess in the first glass can be cylindrical. The term "cross-section" refers to both a cross-sectional area and a cross-sectional shape. These design options can preferably also be used for the recess in the second glass. The length of each recess is the dimension of the recess in the thickness direction of the glass.

According to an alternative preferred embodiment of the invention, the recess in the first glass comprises a first recess area with a first cross-sectional area and a second recess area with a second cross-sectional area. The second recess area is located closer to the second glass than the first recess area. In particular, the second cross-sectional area is larger than the first cross-sectional area. Furthermore, a space in the second recess area between the first glass and the base area of the decorative element is advantageously filled with bonding material of the connecting intermediate layer. This enables a particularly strong bond between the base area of the decorative element and the first glass. Preferably, the first recess area and the second recess area have identical cross-sectional shapes. For example, the first and second recess areas can each have a circular cross-section.

Preferably, the recess of the base area of the decorative element is arranged opposite the second recess area and connected to the second recess area via the connecting intermediate layer. Here, a space of the second
The recessed area between the first glass and the base of the decorative element, including the indentation, is advantageously filled with bonding material from the connecting intermediate layer. Due to the provision of the second recessed area with the second cross-sectional surface and the indentation of the decorative element, a sufficient quantity of bonding material is available to secure the base of the decorative element within the watch glass.

In particular, the clear distance between the base area of the decorative element and the recess of the first glass shall be between 0.1 mm (inclusive) and 0.6 mm (inclusive), and in particular between 0.2 mm (inclusive) and 0.5 mm (inclusive).

As already described, the second glass can also preferably have a recess which, together with the through recess of the first glass, forms the watch glass recess. The recess of the second glass is preferably through-hole.

It is advantageous if the base area of the decorative element is arranged at least partially, and in particular completely, within the watch glass recess. This means that it is advantageous if a base area is positioned at least partially, and in particular completely, in both the first and the second recess.

Preferably, a space in the watch glass recess, defined by the first glass, the second glass and the base area, is filled with bonding material of the connecting intermediate layer, so that the decorative element is connected to the first glass and the second glass via the bonding material.

It follows that the bonding intermediate layer advantageously comprises both the bonding material located between opposing surfaces of the glasses and the bonding material located in the space of the watch glass recess between the first glass, the second glass, and the base of the decorative element. In other words, the bonding material between the opposing surfaces of the glasses and the bonding material in the space already described are advantageously to be understood as a single/continuous bonding intermediate layer that serves to bond both the first glass to the second glass and the decorative element to the glasses.

Furthermore, the formulation that the space of the watch glass recess between the first glass and the second glass is filled with bonding material of the connecting intermediate layer advantageously means that the space is completely filled.

Such an arrangement is particularly advantageous because, in the event of a potential impact on the additional area of the decorative element, the decorative element is fixed by its base area, which is at least partially located in the watch glass recess, whereby the impact energy is distributed to both glasses via the connecting intermediate layer.

Preferably, the maximum thickness of the bonding interlayer between the first glass and the second glass in the thickness direction of the glasses is smaller than the maximum thickness of the bonding material of the bonding interlayer in the space between the first glass, the second glass and the decorative element in the thickness direction of the glasses.

Preferably, the maximum thickness of the bonding interlayer between the first glass and the second glass in the thickness direction of the glasses is smaller than the maximum thickness of the bonding material of the bonding interlayer in the space between the first glass, the second glass and the decorative element in a direction perpendicular to the thickness direction of the glasses.

Preferably, the connecting material in the space between the first glass, the second glass and the decorative element has a maximum thickness in the thickness direction of the glasses and/or in a direction perpendicular to the thickness direction of the glasses of at least 2 mm, preferably at least 3 mm, more preferably at least 4 mm, and particularly preferably at least 5 mm.

In particular, an area of the decorative element may directly contact the first glass and/or the second glass.

Preferably, the decorative element has a base area and an additional area.

The base area preferably comprises a first sub-area and a second sub-area. The space of the watch glass recess between the first glass, the second glass, the first sub-area, and the second sub-area is advantageously filled with bonding material of the connecting intermediate layer.

Preferably, the first sub-region of the base area can be inclined to an axis perpendicular to the glass. Similarly, the second sub-region of the base area can preferably be inclined to an axis perpendicular to the glass.

"Inclined" with reference to the first sub-area and the second sub-area advantageously means that the first sub-area and the second sub-area do not extend parallel to an axis perpendicular to the glasses.

The axis perpendicular to the glass is in particular parallel to the thickness direction of the glass.

The first sub-area and/or the second sub-area are particularly preferred to be conically shaped.

The first sub-area and the second sub-area advantageously define a space which, when the decorative element is installed in the watch glass, partially or completely corresponds to the space of the watch glass recess between the first glass, the second glass, and the decorative element. This means that, when the decorative element is in place in the watch glass recess, this space is filled with the bonding material of the connecting intermediate layer.

Preferably, the second sub-section has a greater inclination than the first sub-section. In other words, the second sub-section is preferably inclined more steeply to the axis perpendicular to the glass than the first sub-section.

Preferably, the angle between the first sub-region and the second sub-region is less than 90 degrees, preferably between 10 degrees and 50 degrees, and particularly preferably between 20 degrees and 40 degrees.

Advantageously, the bonding material of the connecting intermediate layer in the space between the first glass, the second glass, and the base area of the decorative element has a triangular cross-section in a section perpendicular to the glass panes. The plane of the section is defined in particular by the thickness direction of the glass panes and the direction perpendicular to the thickness direction.

In particular, the first sub-section of the base area faces away from the interior of the watch case when the decorative element is positioned in the recess of the watch crystal. The second sub-section, however, faces towards the interior of the case.

Preferably, the second sub-area projects beyond the underside of the second glass, in particular by a maximum of 20%, preferably by a maximum of 10%, and most preferably by a maximum of 5% of the thickness of the watch glass. The thickness of the watch glass corresponds in particular to the sum of the thicknesses of the first glass, the second glass, and the bonding intermediate layer in the area between the first glass and the second glass.

According to an alternative embodiment of the invention, the second sub-area does not protrude beyond the underside of the second glass.

In particular, the second sub-section can end in the watch crystal recess, specifically in the recess of the second crystal. Alternatively, an end section of the second sub-section can be flush with the underside of the second crystal. The term "end section" here refers to... in particular the part of the second sub-area which has the greatest distance in the thickness direction of the glasses from the top of the first glass.

Thus, according to one embodiment, the base area can be arranged completely in the watch glass recess, or according to another embodiment, it can be arranged partially in the watch glass recess and partially extend beyond the underside of the second glass.

Preferably, the first recess has a first recess area and a second recess area. Advantageously, the first and second recess areas of the first recess have different shapes.

Accordingly, the second recess can preferably have a first recess area and a second recess area. The first and second recess areas of the second recess advantageously have different shapes.

Advantageously, the first recess area of the first recess has a first cross-sectional area, and the second recess area of the first recess has a second cross-sectional area. In particular, the first cross-sectional area is larger than the second cross-sectional area. Furthermore, the first recess area of the first recess preferably faces away from the second glass, while the second recess area faces towards the second glass.

Accordingly, the first recess area of the second recess can advantageously have a first cross-sectional area, and the second recess area of the second recess can have a second cross-sectional area. In particular, the first cross-sectional area is larger than the second cross-sectional area. Furthermore, the first recess area of the second recess preferably faces the first glass, while the second recess area faces away from the first glass.

Preferably, the first recess area of the first recess can be conical. Preferably, the second recess area of the first recess can be cylindrical.

Accordingly, the first recess area of the second recess can preferably be conical. Preferably, the second recess area of the second recess can be cylindrical.

However, it is also possible that the first exclusion area of the first exclusion and/or the second exclusion area of the first exclusion and/or the first The recess area of the second recess and/or the second recess area of the second recess are cylindrical, with the same or different diameters.

Preferably, the first sub-region of the base region can contact the first glass, in particular the first recess region and/or the second recess region of the first recess. Similarly, the second sub-region of the base region can preferably contact the second glass, in particular the first recess region and/or the second recess region of the second recess.

Preferably, the first sub-area can be bonded to the first glass and/or the second glass via their contact surfaces, in particular by gluing.

In particular, such a material-bonded connection may be provided between the first sub-area and the first recess area of the first recess and/or between the second sub-area and the second recess area of the second recess.

In particular, the decorative element can only be bonded, especially glued, to the first glass at its point of contact. Specifically, such a connection can only be provided between the first sub-area and the first, especially conical, recess area of the first recess.

The described bonding method, in particular adhesive bonding, between the decorative element and the first glass at their contact surfaces has the advantage that contact between the bonding layer and the ambient air is avoided in the finished watch crystal, thus preventing humidity from reaching the bonding layer. This ensures the adhesive properties of the bonding layer in the finished watch crystal, even if the bonding layer is made of a hygroscopic material. Furthermore, this prevents material from the initial bonding layer from escaping the watch crystal recess during the bonding process. In addition, the described bonding method offers the advantage that the decorative element remains stationary in the watch crystal recess during the bonding process. This allows for precise positioning of the decorative element within the finished watch crystal. Moreover, it ensures a particularly strong bond between the decorative element and the watch crystal.

Advantageously, a material, in particular an adhesive material, is used as the material for the previously described material-bonded connection, which can withstand temperatures between 110 degrees Celsius. and remains resistant to temperatures up to 150 degrees Celsius, especially between 130 degrees Celsius and 145 degrees Celsius, is water-resistant and does not react with the material of the initial intermediate layer.

For example, a two-component epoxy resin or a waterproof UV adhesive can be used.

According to an alternative embodiment of the invention, instead of an adhesive bond at the contact point between the first glass and the decorative element, in particular between the first glass or the first recess area of the first recess and the first sub-area of the base area, a sealing element may preferably be provided.

Accordingly, according to an alternative embodiment of the invention, instead of an adhesive bond at the contact point between the second glass and the decorative element, in particular between the second glass or the first recess area of the first recess and the second recess area, a sealing element may preferably be provided.

It should be noted that, with regard to the disclosure of the present invention, the features of the watch glass described above, in particular of the first glass, the second glass, the connecting intermediate layer and the decorative element, can be combined with each other as desired, as long as they do not exclude each other.

Furthermore, the present invention relates to a watch comprising a watch crystal as previously described. The watch, in particular, has a case on which the watch crystal is arranged. Preferably, the watch crystal is mounted in the case and bonded to it. The watch crystal is arranged on the case such that the first crystal faces away from any interior of the case. In other words, in the watch, the first crystal is the outer crystal.

The watch is preferably a wristwatch.

• Bereitstellen des ersten Glases und des zweiten Glases,
• Ausbilden der Ausnehmung im ersten Glas,
• Bereitstellen des dekorativen Elements, insbesondere des Schmucksteins,
• Anordnen des dekorativen Elements in der Ausnehmung, und
• Verbinden des ersten Glases mit dem zweiten Glas über die verbindende Zwischenschicht; insbesondere nach dem Anordnen des dekorativen Elements in der Ausnehmung.

A method is proposed for manufacturing the watch glass described above, which includes the following steps:

• Providing the first glass and the second glass,
• Forming the recess in the first glass,
• Providing the decorative element, in particular the gemstone,
• Arranging the decorative element in the recess, and
• Joining the first glass to the second glass via the connecting intermediate layer; especially after arranging the decorative element in the recess.

To provide a decorative element designed as a gemstone, a raw stone can be polished so that the base area and/or the additional area are shaped.

The recess can preferably be formed into the first glass by laser drilling or mechanical drilling.

After the recess has been formed, the top and/or bottom of the first glass is preferably ground. This removes any potential chips that may have occurred during the recess formation process.

The joining of the first glass to the second glass via the joining intermediate layer preferably comprises heating the arrangement of the first glass, the second glass and an intermediate initial layer at a temperature between 110 degrees Celsius and 150 degrees Celsius, in particular between 130 degrees Celsius and 145 degrees Celsius.

The initial intermediate layer can preferably be an organic or inorganic bonding or adhesive compound or adhesion layer, or an elastic film (also: composite film, in particular an adhesive film). In particular, the initial intermediate layer can be made of casting resin. The casting resin can be, for example, a two-component epoxy resin or a UV-curing one-component adhesive.

Furthermore, the joining of the first glass to the second glass can preferably be carried out under vacuum to remove air from the space between the glasses, and under pressure, in particular 1 bar, on the arrangement of the glasses to achieve a strong bond between the glasses.

This creates an airtight seal between the first and second panes of glass, as well as between the first pane and the base of the decorative element. Due to the absence of voids or air bubbles between the decorative element and the bonding layer, a vacuum effect occurs, pressing the decorative element into the recess by the air pressure. If the decorative element is subjected to mechanical stress, causing it to wobble within the recess, the vacuum draws the base of the decorative element into place. Thus, the base is held not only by the bonding layer but also by the vacuum effect described above.

The initial intermediate layer can be a liquid adhesive compound, which then hardens to bond the glasses together and the decorative element to the first glass.

To provide the finished watch glass, it is advantageous to remove material from the initial intermediate layer which may have potentially flowed out of the space between the glasses after the bonding process between the first glass and the second glass.

The present invention, due to its ease of implementation and universal applicability, enables a wide variety of designs. For example, faceted gemstones, gemstones in all cuts such as cabochons, metal indices, relief numerals, pictorial representations such as the twelve signs of the zodiac, pearls, etc., can be easily attached to the watch crystal. The purist design, in which only the top surface of the base area or only the additional area of the decorative element is visible, and no other material besides the watch crystal, allows for a purity of style and effect in both the decorative element and the watch crystal. For example, a watch with a white mother-of-pearl dial and twelve small, white, applied half-pearls retains its mother-of-pearl effect undisturbed. Furthermore, the present invention ensures a waterproof watch crystal and a secure attachment of the decorative element to the watch crystal.

Fig. 1

eine schematische Draufsicht einer erfindungsgemäßen Uhr, welche ein Uhrglas gemäß einem ersten Ausführungsbeispiel der vorliegenden Erfindung aufweist,

Fig. 2

eine schematische perspektivische Ansicht des Uhrglases aus Fig. 1,

Fig. 3

eine schematische Schnittansicht des Uhrglases gemäß dem in Fig. 1 gekennzeichneten Schnitt A-A,

Fig. 4

eine schematische Schnittansicht eines Teils des Uhrglases gemäß Schnitt A-A,

Fig. 5

eine weitere schematische Schnittansicht eines Teils des Uhrglases gemäß Schnitt A-A,

Fig. 6

eine schematische Schnittansicht eines Teils eines Uhrglases nach einem zweiten Ausführungsbeispiel der vorliegenden Erfindung,

Fig. 7

eine schematische Schnittansicht eines Teils eines Uhrglases nach einem dritten Ausführungsbeispiel der vorliegenden Erfindung,

Fig. 8

eine schematische Schnittansicht eines Teils eines Uhrglases nach einem vierten Ausführungsbeispiel der vorliegenden Erfindung, und

Fig. 9

eine schematische Schnittansicht eines Teils eines Uhrglases nach einem fünften Ausführungsbeispiel der vorliegenden Erfindung.

Further details, advantages, and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the drawing, wherein identical or functionally equivalent elements are provided with the same reference numerals. The drawing shows:

Fig. 1

a schematic top view of a watch according to the invention, which has a watch glass according to a first embodiment of the present invention,

Fig. 2

a schematic perspective view of the watch glass made of Fig. 1 ,

Fig. 3

a schematic sectional view of the watch glass according to the one in Fig. 1 marked section AA,

Fig. 4

a schematic sectional view of part of the watch glass according to section AA,

Fig. 5

another schematic sectional view of part of the watch glass according to section AA,

Fig. 6

a schematic sectional view of a part of a watch glass according to a second embodiment of the present invention,

Fig. 7

a schematic sectional view of a part of a watch glass according to a third embodiment of the present invention,

Fig. 8

a schematic sectional view of a part of a watch glass according to a fourth embodiment of the present invention, and

Fig. 9

a schematic sectional view of a part of a watch glass according to a fifth embodiment of the present invention.

The following refers to the Figures 1 to 5 A watch 100 with a watch glass 10 according to a first embodiment of the present invention is described in detail.

As from Figure 1 As can be seen, the watch 100 has a case 11 in which the watch glass 10 is arranged. In particular, the watch glass 10 is bonded to the case 11 around its circumference. The case 11 and the watch glass 10 are circular, but can have any other shape, such as a rectangle, a polygon, etc.

According to Figures 1 and 2 The watch crystal 10 features twelve decorative elements 3 arranged circumferentially at equal intervals. However, the position and number of these decorative elements 3 can be freely chosen depending on the watch design. For example, the watch crystal 10 can be fitted with only one, two, or four decorative elements 3. The watch 100 also includes a dial 12, which may be made of gold, three hands 13 for displaying the hours, minutes, and seconds, and two lugs for attaching the case 11 to a strap 14.

In this exemplary embodiment, the decorative elements are 3 gemstones with a cabochon cut. However, gemstones with other cuts and other types of decorative elements, such as metal inlays, can also be used as the decorative elements 3 of the present invention.

Figure 3 shows a sectional view of the watch glass 10 according to section AA in Figure 1 .

It follows that the watch glass 10 comprises a first glass 1 and a second glass 2, which are preferably designed as flat glass discs. However, it is also possible to design the glasses 1 and 2 as curved with the same curvature at their contact surfaces.

The first glass 1 and the second glass 2 lie on top of each other and are bonded together over their entire surface by a connecting intermediate layer 5. This bond, created by the intermediate layer 5, results in an airtight and watertight connection between the glass 1 and 2.

The first glass 1 faces away from an interior space 15 of the housing 11, and the second glass 2 faces the interior space 15 of the housing 12. Thus, the first glass 1 is the glass that the light first strikes. Within the scope of the invention, the first glass 1 can also be referred to as the upper glass or outer glass, and the second glass as the lower glass or inner glass.

Advantageously, the first glass 1 is made of sapphire glass, which has high scratch resistance. The second glass 2 is made of mineral glass. However, other materials, such as other types of glass or plastic, are also possible for both the first glass 1 and the second glass 2.

Each decorative element 3 has a continuous recess 4 formed in the first glass 1. All recesses 4 of the first glass 1, as well as all decorative elements 3, are advantageously identical. Therefore, the following description refers only to one decorative element 3 and its associated recess 4 in the first glass 1.

Unlike the first glass 1, the second glass 2 is formed completely. That is, the second glass 2 has no recess.

The decorative element 3, which is formed in one piece, has a base area 31 and an additional area 32. The base area 31 is arranged without a mounting in the continuous recess 4 of the first glass 1 and is in direct contact with the connecting intermediate layer 5. "Without a mounting" means that no mounting is provided in the watch glass 10 or in the recess 4 of the first glass 1 to receive and hold the decorative element. Rather, the decorative element 3 is held in the recess 4 by the contact between the base area 31 and the connecting intermediate layer 5.

In particular, an end face 33 of the base region 31 is completely in direct contact with the connecting intermediate layer 5. The end face 33 of the base region 31 is the side of the decorative element 3 that faces the second glass 2 and is perpendicular to a thickness direction 500 of the glasses 1, 2.

The Figures 3 to 5 It can be seen that, in addition to the end face 33, a circumferential surface 34 of the base area 31 is also partially in direct contact with the connecting intermediate layer 5. In other words, the end face 33 of the base area 31 of the decorative element 3 is embedded in the connecting intermediate layer 5.

This means that the connecting intermediate layer 5 is both a connecting material located between opposing surfaces 19, 29 of the first glass 1 and the second. The glass 2 is located, as well as the connecting material which is located between the circumferential surface 34 of the base area 31 of the decorative element 3 and the first glass 1 or the recess 4 of the first glass 1.

The front face 33 and the part of the circumferential surface 34 of the decorative element 3 which is in direct contact with the connecting intermediate layer 5 are also referred to as holding areas within the scope of the invention, since the decorative element 3 is held in the watch glass 10 by their contact with the connecting intermediate layer 5.

Advantageously, the connecting intermediate layer 5 is formed from a transparent laminating film (composite film).

As from Figure 3 As can be seen, the bonding interlayer 5 has a first thickness 501 at every point between the opposing surfaces 19, 29 of the glass panes 1, 2, in particular at the end face 33 of the decorative element 3, corresponding to the values defined in the general part of the description. At the circumferential surface 34 of the base region 31 of the decorative element 3, the bonding interlayer 5 has a second thickness 502, which is less than the first thickness 501. In particular, the second thickness 502 of the bonding interlayer 5 between the circumferential surface 34 of the base region 31 of the decorative element 3 and the recess 4 of the first glass pane 1, or the first glass pane 1 perpendicular to the thickness direction 500 of the glass panes 1, 2, is preferably between 0.1 mm (inclusive) and 0.6 mm (inclusive), in particular between 0.2 mm (inclusive) and 0.5 mm (inclusive).

The recess 4 has the same cross-sectional shape and area along its entire length. In particular, the recess 4 is cylindrical. Due to its continuous design, the length of the recess 4 corresponds to the thickness 504 of the first glass 1. Accordingly, the base region 31 of the decorative element 3 is cylindrical. Thus, the connecting intermediate layer 5 is hollow-cylindrical on the portion of the circumferential surface 34 of the base region 31 that is in direct contact with the intermediate layer 5.

The complete base area 31 of the decorative element 3 is arranged only in the recess 4 of the first glass 1.

In particular, the base area 31 of the decorative element 3 is flush with the surface 19 (also: underside) of the first glass 1 facing the second glass 2. Alternatively, the base area 31 of the decorative element 3 can end in the recess 4, i.e., have a length that is less than the depth of the recess 4.

The additional area 32 of the decorative element 3 projects beyond the first glass 1 in the thickness direction 500 of the glass 1, 2 and in every direction 505 perpendicular to the thickness direction 500. In other words, the additional area 32 projects completely around, i.e., over 360 degrees, beyond the recess 4. Thus, the additional area 32 is located above the first glass 1. In particular, the additional area 32 lies on top of the first glass 1. Preferably, there is no material bond between the additional area 32 and the first glass 1.

Preferably, the cross-sectional area of the additional area 32 of the decorative element 3 at the recess 4, i.e. the area of the underside 36 of the additional area 32, is larger than the cross-sectional area of the recess 4 on the plane of the top side 18 of the first glass 1.

As already described, in this embodiment the decorative element 3 is a gemstone with a cabochon cut. Here, the additional area 32 corresponds to that area of the gemstone which is cut in the cabochon shape.

In particular, the decorative element 3 is designed such that the ratio of the length 300 of the base region 31 of the decorative element 3 in the thickness direction 500 of the glass 1, 2 to the length 301 of a projection of the additional region 32 in any direction 505 perpendicular to the thickness direction 500 is at most "two to one". Specifically, the projection is the portion of the additional region 32 that extends beyond the base region 31. Advantageously, the length 301 of the projection is measured at the location of the recess 4, i.e., on the plane of the underside 36 of the additional region 32. For the decorative element 3, the length 301 of the projection is at its maximum at this location.

Because of this ratio, the base area 31 is not very long, which means that, firstly, the base area 31 is obscured by the additional area 32. Secondly, this ratio causes the base area 31 to visually disappear and thus no longer be perceived by an observer. This is demonstrated by... Figures 4 and 5 explained in more detail.

In Figure 4 A light ray 601 is shown striking the first glass 1 at an oblique angle. Due to the different optical densities of air and the first glass 1, the light ray 601 is refracted at the top surface 18 of the first glass 1. In particular, due to the higher optical density of the first glass 1 compared to air, it is refracted towards the normal 600. Since the base region 31 is not very long, the refracted light ray 601 does not reach the base region 31, but passes through the connecting intermediate layer 5 and the second glass 2. This is also due to the fact that the first glass 1 is made of sapphire glass, which has a relatively high optical density. has a refractive index (of approximately 1.77), which leads to a relatively strong refraction of the light ray 601 towards the normal 600.

However, depending on the angle at which the light rays strike the first glass 1, it is possible that some of the light rays will reach the base area 31 of the decorative element 3 and be reflected outwards from it. Figure 5 A light ray 602, reflected outwards from the base region 31, is shown. Due to the described configuration of the additional region 32 in relation to the base region 31, the reflected light ray 602 is reflected at an angle 603 that is larger than the total reflection angle 604 of the first glass 1. Thus, the light ray 602 is totally reflected at the inner surface of the top 18 of the first glass 1 and passes through the connecting intermediate layer 5 and the second glass 2. This results in light that strikes the base region 31 and is reflected from it not reaching the viewer's eye.

Thus, the base area 31 remains invisible and at the same time ensures a stable arrangement of the decorative element, especially its additional area 32.

To manufacture the watch crystal 10, the first crystal 1 and the second crystal 2 are first prepared. In particular, the through-holes 4 in the first crystal 1 are formed. This can be done using a laser process or a mechanical drilling process.

After forming the recesses 4, the top 18 and bottom 19 of the first glass 1 are ground down to remove any potential breakouts in the first glass 1 caused by forming the recesses 4.

To join the glasses 1,2, an initial intermediate layer, in particular a laminating film, is placed on the second glass 2.

The decorative elements 3 are placed into the corresponding recesses 4 of the first glass 1 and the first glass 1 is placed on top of the second glass 2.

Subsequently, air is removed from the space between the first glass 1 and the second glass 2. This is achieved by creating a vacuum encompassing the entire assembly consisting of the first glass 1, the second glass 2, the intermediate initial layer, and the decorative elements 3. The vacuum is preferably maintained throughout the entire bonding process (also known as lamination). The assembly, comprising the first glass 1, the second glass 2, the intermediate initial layer, and the decorative elements 3, is heated at a temperature between 110°C and 150°C, particularly between 130°C and 150°C. The initial interlayer is heated to between 145 and 145 degrees Celsius, so that it becomes doughy or liquid. A pressure of 1 bar is then applied to the assembly, so that finally the first glass 1 is joined to the second glass 2. This allows the material of the initial interlayer to easily enter part of the space in the recess 4 between the first glass 1 and the base 31. Capillary action, which occurs due to the nearly identical diameters of the cylindrical recess 4 and the cylindrical base 31, also contributes to filling this space with the material of the initial interlayer.

In an extended lamination process, in addition to the normal air pressure of 1 bar, which presses down on the previously described arrangement, an additional pressure of up to 8 bar can preferably be built up.

After the described bonding process, which takes place primarily in an autoclave, the initial intermediate layer transforms into the bonding intermediate layer 5. This layer joins the first glass 1 to the second glass 2 in the finished watch glass 10 and ensures the stable arrangement of the decorative element 3 on the watch glass 10. Specifically, a partial, hollow cylindrical encapsulation of the base area 31 of the decorative element 3 is formed from the bonding material of the intermediate layer 5.

By encasing the base area 31 of the decorative element 3, the adhesive surface on which the decorative element 3 is held on the watch glass 10 increases many times over, and thus also the security of a long-lasting arrangement of the decorative element 3 on the watch glass 10.

The proportion of the circumferential area 34 of the base area 31 in the finished watch glass 10 that is in direct contact with the connecting intermediate layer 5 can be controlled in particular by the initial intermediate layer, especially its thickness.

The present invention enables the attachment of decorative elements 3 to a watch glass 10, in particular decorative elements 3 each having a base region 31 arranged in a recess 4 of the first glass 1 and an additional region 32 projecting beyond the recess 4 of the first glass 1, without the use of a setting. Thus, the appearance of the proposed watch glass 10 is determined solely or fundamentally by the decorative elements 3, while also ensuring the break resistance of the watch glass 10 and the stability of the connection between the decorative elements 3 and the first glass 1.

In Figure 6 A sectional view of a watch glass 10 according to a second embodiment of the present invention is shown.

The watch glass 10 according to the second embodiment differs fundamentally from that according to the first embodiment in that, in the watch glass 10 of the second embodiment, the entire circumferential surface 34 of the base region 31 of the decorative element 3 is in direct contact with the bonding intermediate layer 5. Thus, the watch glass 10 has a hollow cylindrical shell (also: hollow cylindrical region) made of bonding material around the entire base region 31 of the decorative element 3. The hollow cylindrical shell is part of the bonding intermediate layer 5.

The phrase "complete circumferential area" means that the base area 31 is in contact with the connecting intermediate layer 5 over its entire length and over 360 degrees.

Because of this, and because the additional area 32 is located on the top side 18 of the first glass 1, the bottom side 36 of the additional area 32 partially contacts the connecting intermediate layer 5.

Here, the front face 33 and the entire circumferential surface 34 of the base area 31 of the decorative element 3 serve as holding areas by which the decorative element 3 is attached to the watch glass 10.

Figure 7 shows a sectional view of a watch glass 10 according to a third embodiment of the present invention.

The difference between the watch glass 10 according to the third embodiment and the watch glass 10 of the second embodiment is that the base area 31 of the decorative element 3 of the third embodiment has a fully circumferential recess 35 in its circumferential surface 34.

The annular recess 35 is in direct contact with the connecting intermediate layer 5. This means that the recess 35 is filled with the bonding material of the connecting intermediate layer 5. Thus, the base area 31 of the decorative element 3 is anchored in the recess 4 by means of the connecting intermediate layer 5. In other words, the bonding material in the recess 35 acts as an undercut for the connecting intermediate layer 5, further preventing the decorative element 3 from being removed from the recess 4.

The connecting intermediate layer 5 has a first thickness 501 between the first glass 1 and the second glass 2 and a second thickness 502 between the first glass 1 and the base region 31 over its entire length up to the point of the depression 35, where the connecting intermediate layer 5 has a third thickness 503. The third thickness 503 is greater than the second thickness 502. The values given in the general part of the description for the thickness of the bonding intermediate layer 5 between the first glass 1 and the base area 31 also apply in particular to the first thickness 501 and/or the second thickness 502 and/or the third thickness 503.

The recess 35 creates an even more stable connection between the decorative element 3 and the first glass 1.

In Figure 8 A section of a watch glass 10 according to a fourth embodiment is shown.

The watch glass 10 according to the fourth embodiment has a stepped recess 4.

In particular, the recess 4 comprises a first recess area 41 with a first cross-sectional area 410 and a second recess area 42 with a second cross-sectional area 420.

The second recess area 42 is located closer to the second glass 2 than the first recess area 41, with the second cross-sectional area 420 being larger than the first cross-sectional area 410.

Regarding the cross-sectional shapes of the recess areas 41 and 42, the first recess area 41 and the second recess area 42 have identical cross-sectional shapes. In particular, both recess areas 41 and 42 are cylindrical.

As with the watch glass 10 of the third embodiment, the base area 31 of the decorative element 3 also has a fully circumferential recess 35 in its circumferential surface 34 in the watch glass 10 according to the fourth embodiment.

The recess 35 is positioned opposite the second recess area 42 and connected to the second recess area 42 via the connecting intermediate layer 5. The space between the second recess area 42 and the base area 31 of the decorative element 3, including the recess 35, is filled with bonding material from the connecting intermediate layer 5.

Thus, a particularly strong connection of the base area 31 of the decorative element 3 to the first glass 1 is created. Since the recess 35 is formed at the lower end, i.e., at the end of the base area 31 of the decorative element 3 facing the second glass, and the second recess area 42 with its second cross-sectional area 420 being larger than that of the first recess area 41, is located closer to the second glass. 2, the base area 31 can also withstand a torque caused by the auxiliary area 32 striking the base area.

In this embodiment, the first recess area 41 is not in contact with the connecting intermediate layer 5. In other words, there is no connecting material of the connecting intermediate layer 5 in the space between the first recess area 41 and the circumferential surface 34 of the base area 31. However, an embodiment in which connecting material of the connecting intermediate layer 5 is provided in the space between the first recess area 41 and the circumferential surface 34 of the base area 31 is also possible.

Figure 9 shows a sectional view of a watch glass 10 according to a fifth embodiment of the present invention, which is incorporated into the watch 100 of Figure 1 can be used.

As can be seen from Figure 9 The result is that the watch glass 10 also comprises a first glass 1 and a second glass 2, which are connected to each other via a connecting intermediate layer 5.

The first glass 1 has a continuous recess 4, and the second glass 2 also has a continuous recess 6. The continuous recess 4 of the first glass 1 and the continuous recess 6 of the second glass 2 together form a watch glass recess 7. The recess 4 of the first glass 1 can also be referred to as the first recess 4, and the recess 6 of the second glass 2 can also be referred to as the second recess 6.

Furthermore, the watch glass 10 includes a decorative element 3 designed as a gemstone, which has a base area 31 and an additional area 32.

The base area 31 is arranged without a frame in the watch glass recess 7. In other words, the base area 31 is arranged without a frame in both the first recess 4 and the second recess 6.

Furthermore, in this embodiment, the base area 31 also projects beyond a lower surface 28 of the second glass 2. However, it is also possible that the base area 31 is completely enclosed within the watch glass recess 7.

The additional area 32 extends beyond the top surface 18 of the first glass 1. In other words, the additional area 32 is the area of the decorative element 3 that is located above the top surface 18 of the first glass 1.

In particular, the additional area 32 extends in the thickness direction 500 of the glasses 1, 2 and in the direction perpendicular to the thickness direction 505, especially in every direction perpendicular to the thickness direction 505.

In this embodiment, the additional area 32 of the decorative element 3 comprises a plate 37, upper facets 38, and parts of lower facets 39 of the gemstone. Here, the plate 37, the upper facets 38, and the parts of the lower facets 39 of the decorative element 3 are in direct contact with air. Thus, light can directly strike the decorative element 3.

However, other shapes for the decorative element 3 or other cuts for the gemstone are also conceivable. Thus, the additional area 32 of the decorative element 3 can, instead of the table 37 and the top facets 38, have a cabochon-cut area or be designed as such. In particular, the additional area 32 can be the area of the gemstone that is cut in the cabochon shape.

Furthermore, the decorative element 3 is designed such that the base area 31, in contrast to the additional area 32, faces the interior 15 of the case 11 and the dial 12 of the watch 100. Conversely, the additional area 32, in contrast to the base area 31, faces away from the interior 15 and the dial 12.

The base area 31 has in particular a first sub-area 311 and a second sub-area 312.

The first sub-area 311 and the second sub-area 312 are each inclined to an axis 102 perpendicular to the glass panes 1 and 2. The axis 102 perpendicular to the glass panes 1 and 2 is parallel to the thickness direction 500 of the glass panes 1 and 2.

The second sub-area 312 has a greater inclination than the first sub-area 311. In other words, the second sub-area 312 is inclined more strongly to the axis 102 perpendicular to the glasses 1, 2 than the first sub-area 311.

In particular, an angle 513 between the first sub-area 311 and the second sub-area 312 is less than 90 degrees, preferably between 10 degrees and 50 degrees, particularly preferably between 20 degrees and 40 degrees.

In particular, the first sub-area 311 and the second sub-area 312 are conical in shape. However, other shapes for the first sub-area 311 and/or the second sub-area 312 are also possible.

The base area 31, in particular its circumferential surface 34, is partially in direct contact with the connecting intermediate layer 5.

In this case, a space 70 of the watch glass recess 7, which is defined by the first glass 1, the second glass 2 and the base area 3, in particular its first sub-area 311 and its second sub-area 312, is completely filled with connecting material 50 of the connecting intermediate layer 5, so that the decorative element 3 is connected to the first glass 1 and the second glass 2 via the connecting material 50.

The connecting intermediate layer 5 advantageously comprises both the connecting material 51, which is located between the opposing surfaces 19, 29 of the glasses 1, 2, and the connecting material 50, which is located in the space 70 of the watch glass recess 7 between the first glass 1, the second glass 2, the first sub-area 311 and the second sub-area 312. In other words, the connecting material 50 in space 70, together with the connecting material 51 between the opposing surfaces 19, 29 of the glasses 1, 2, forms the connecting intermediate layer 5. The connecting intermediate layer 5 is continuous between space 70 and the space between the opposing surfaces 19, 29.

Thus, the connecting intermediate layer 5 serves to connect the first glass 1 with the second glass 2 and the decorative element 3 with both glasses 1, 2.

The first sub-area 311 and the second sub-area 32 define a space 310 which, when the decorative element 3 is mounted in the watch glass 10, is filled with the bonding material 50 of the connecting intermediate layer 5. The space 310 can also be referred to as the recess of the decorative element 3. In particular, when the decorative element 3 is mounted in the watch glass 10, the space 310 corresponds to the space 70 of the watch glass recess 7.

Out of Figure 9 It is further evident that a maximum thickness 507 of the connecting intermediate layer 5 between the first glass 1 and the second glass 2 in the thickness direction 500 of the glasses 1, 2 is smaller than a maximum thickness 506 of the connecting material 50 of the connecting intermediate layer 5 in the space 70 between the first glass 1, the second glass 2, the first sub-area 311 and the second sub-area 312 in the thickness direction 500 of the glasses 1, 2.

Furthermore, the maximum thickness 507 of the bonding intermediate layer 5 between the first glass 1 and the second glass 2 in the thickness direction 500 of the glasses 1, 2 is smaller than a maximum thickness 508 of the bonding material 50 of the bonding intermediate layer 5 in the space 70 between the first glass 1, the second glass 2, the first sub-area 311 and the second sub-area 312 in a direction 505 perpendicular to the thickness direction 500 of the glasses 1, 2.

For example, the maximum thickness of 507 can be up to 0.4 mm, preferably up to 0.5 mm. The maximum thickness of 508 can, for example, be 2 mm.

Furthermore, the connecting material 50 of the connecting intermediate layer 5 in space 70 has a triangular cross-section on a section plane perpendicular to the top surface 18 of the watch glass 10. The section plane is defined by the thickness direction 500 of the glasses 1, 2 and a direction 505 perpendicular to the thickness direction 500.

In this embodiment, the second sub-area 312 of the decorative element 3 projects beyond the underside 28 of the second glass 2, in particular by a maximum of 20%, preferably by a maximum of 10%, and most preferably by a maximum of 5%, of a thickness 512 of the watch glass 10. The thickness 512 of the watch glass 10 corresponds to the sum of a thickness 510 of the first glass 1, a thickness 511 of the second glass 2, and a thickness 509 of the connecting intermediate layer 5 in the area between the first glass 1 and the second glass 2, with all thicknesses 509, 510, and 511 being measured at the same location.

However, it is also possible that the second sub-area 312 of the base area 31 ends in the watch glass recess 7, in particular in the second recess 6. Alternatively, an end area of the second sub-area 312 can be flush with the underside 28 of the second glass 2.

How Figure 9 As can be further seen, the first recess 4 has a first recess area 41 and a second recess area 42. The first recess area 41 has a larger cross-sectional area than the second recess area 42. In particular, the first recess area 41 is conical, while the second recess area 42 is cylindrical.

Accordingly, according to Figure 9 The second recess 6 comprises a first recess area 61 and a second recess area 62. The first recess area 61 has a larger cross-sectional area than the second recess area 62. In particular, the first recess area 61 is conical, while the second recess area 62 is cylindrical.

However, other shapes for the first recess 4 and/or the second recess 6, in particular for recess areas 41, 42, 61, 62, are also possible.

The first (conical) recess area 41 of the first recess 4 is arranged on the top side 18 of the first glass 1, wherein the first (conical) recess area 61 of the The second recess 6 is located on the upper surface 29 of the second glass 2. Similarly, the second (cylindrical) recess area 42 is located on the lower surface 19 of the first glass 1, with the second (cylindrical) recess area 62 being located on the lower surface 29 of the second glass 2.

In particular, the first recess area 41 of the first recess 4 extends over the upper half of the depth of the first recess 1, while the second recess area 42 of the first recess 4 extends over the lower half of the depth of the first recess 4. The same applies to the first recess area 61 and the second recess area 62 of the second recess 6.

To form the conical recess areas 41, 61, the first recess 4 and the second recess 6 on the upper surfaces 18, 28 of the glasses 1, 2 are completely chamfered in the circumferential direction, i.e. over 360 degrees.

As from Figure 9 Furthermore, it can be seen that the first sub-area 311 of the base area 31 abuts the first recess area 41 of the first recess 4 and has a conical shape at the contact point like the first recess area 41. In particular, the first sub-area 311 can be bonded to the first recess area 41 of the first recess 4.

Furthermore, the second sub-area 312 of the base area 31 contacts the second recess area 62 of the second recess 6 and has a cylindrical shape at the contact point, like the second recess area 62. In particular, the second sub-area 312 and the second recess area 62 of the second recess 6 are not bonded together.

Thus, the space 70 of the watch glass recess 7 is defined in particular by the first recess area 41 of the first recess 4, the first sub-area 311, the second sub-area 312 and the second recess area 62 of the second recess 6.

As already described, the decorative element 3 projects beyond the top surface 18 of the watch glass 10 and is partially located in the watch glass recess 4. In particular, the decorative element 3 has a dimension 302 parallel to the thickness direction 500 of the glasses 1, 2, which is greater than 100% of the thickness 512 of the watch glass 10.

However, the decorative element 3 can have a dimension 302 parallel to the thickness direction 500 of the glasses 1, 2, which is smaller than the thickness 512 of the watch glass 10. In this case, the The decorative element 3 should be arranged in such a way that it still extends beyond the top 18 of the watch glass 10.

Furthermore, the decorative element 3 has a maximum cross-sectional area 303 in the direction 505 perpendicular to the thickness direction 500. The maximum cross-sectional area 303 can be at least 1/20, preferably at least 1/16, and particularly preferably at least 1/10, of the area of the top surface 18 of the first glass 1. Advantageously, the cross-section of the decorative element 3 with the maximum cross-sectional area 303 is located above the first glass 1, i.e., in the additional area 32 of the decorative element 3. Thus, the decorative element 3 can appear to float.

To provide the decorative element 3, designed as a gemstone, a rough gemstone is cut such that the base area 31, the first sub-area 311, the second sub-area 312, and the additional area 32 are formed within the decorative element 3. Due to the described shape of the decorative element 3 and its bezel-less arrangement in the watch glass recess 7, the decorative element 3 appears to be suspended. Furthermore, the connecting material 50 in space 70 of the watch glass recess 7 forms an undercut in the connecting intermediate layer 5, which, in addition to the connecting properties of the connecting material 50, ensures that the decorative element 3 cannot be removed from the watch glass recess 7.

In addition to the foregoing written description of the invention, explicit reference is hereby made to the graphic representation of the invention in the following for its supplementary disclosure. Figs. 1 to 9 Reference made to.

Reference symbol list

1

first glass

2

second glass

3

decorative element

4

Exclusion

5

Intermediate shift

6

Exclusion

7

watch glass recess

10

watch glass

11

Housing

12

dial

13

pointer

14

Connection for a wristband

15

interior

18

Top

19

Area

28

bottom

29

Area

31

Basic area

32

Additional area

33

Front

34

Perimeter area

35

in-depth

36

bottom

37

board

38

upper facet

41

first exclusion area

42

second exclusion area

50

Connecting material

51

Connecting material

61

first exclusion area

62

second exclusion area

70

Space

100

Clock

102

Axle 300 length

301

length

302

measure

303

cross-sectional area

310

space

311

first sub-area

312

second sub-area

410

first cross-sectional area

420

second cross-sectional area

500

Thickness direction

501

first thickness

502

second thickness

503

third thickness

504

thickness

505

Direction perpendicular to the thickness direction

506

thickness

507

thickness

508

thickness

509

thickness

510

thickness

511

thickness

512

thickness

513

angle

600

Lot

601

beam of light

602

beam of light

603

angle

604

angle of total reflection

Claims (14)

1. A watch glass (10) comprising:

   • a first glass (1),

   • a second glass (2), and

   • a decorative element (3), in particular a gemstone,

   • wherein the first glass (1) and the second glass (2) are connected to one another via a connecting intermediate layer (5),

   • wherein the first glass (1) has a continuous recess (4),

   • wherein the decorative element (3) has a base region (31) which is arranged without a mount in the recess (4) and is in direct contact with the connecting intermediate layer (5),

   • wherein the decorative element (3) has an additional region (32) which extends beyond the first glass (1), and

   • wherein a ratio of a length (300) of the base region (31) of the decorative element (3) in the thickness direction (500) of the glasses (1, 2) to a length (301) of an overhang of the additional region (32) in a direction (505) perpendicular to the thickness direction (500) is selected such that light which can be reflected by the base region (31) can be totally reflected at an inner surface of an upper side (18) of the first glass (1), and/or such that at least some of the light which enters the first glass (1) does not reach the base region (31).
2. The watch glass according to claim 1, wherein an end side of the base region (31) and/or a circumferential surface (34) of the base region (31) of the decorative element (3) are at least partially, in particular completely, in direct contact with the connecting intermediate layer (5).
3. The watch glass according to claim 1 or 2, wherein the base region (31) of the decorative element (3) is arranged completely in the recess (4) of the first glass (1).
4. The watch glass according to any one of the preceding claims, wherein the base region (31) is formed in a pin-shaped manner.
5. The watch glass according to any one of the preceding claims, wherein the base region (31) is arranged flush with a surface (19) of the first glass (1) facing the second glass (2) or wherein the base region (31) ends in the recess (4) of the first glass (1).
6. The watch glass according to any one of the preceding claims, wherein the base region (31) of the decorative element (3) has an, in particular circumferential, depression (35), in particular in the circumferential surface (34) of the base region (31).
7. The watch glass according to any one of the preceding claims, wherein the additional region (32) is arranged on the first glass (1).
8. The watch glass according to any one of the preceding claims, wherein the ratio of the length (300) of the base region (31) of the decorative element (3) in the thickness direction (500) of the glasses (1, 2) to the length (301) of the overhang of the additional region (32) in the direction (505) perpendicular to the thickness direction (500) is at most "2:1".
9. The watch glass according to any one of the preceding claims, wherein the recess (4) of the first glass (1) has the same cross-section over its entire length.
10. The watch glass according to any one of claims 1 to 8, wherein the recess (4) of the first glass (1) has a first recess region (41) with a first cross-sectional area (410) and a second recess region (42) with a second cross-sectional area (420), wherein the second cross-sectional area (420) is larger than the first cross-sectional area (410) and the second recess region (42) is arranged closer to the second glass (2) than the first recess region (41).
11. The watch glass according to claim 10, wherein the depression (35) of the base region (31) of the decorative element (3) is arranged opposite the second recess region (42) and is connected to the second recess region (42) via the connecting intermediate layer (5).
12. The watch glass according to any one of claims 1, 2, 4, 6 to 9, wherein the second glass (2) has a recess (6) which, together with the continuous recess (4) of the first glass (1), forms a watch glass recess (7), wherein the decorative element (3) is arranged in the watch glass recess (7) and a space (70) of the watch glass recess (7), which is defined by the first glass (1), the second glass (2) and the decorative element (3), is filled with connecting material (50) of the connecting intermediate layer (5), so that the decorative element (3) is connected to the first glass (1) and the second glass (2) via the connecting material (50).
13. The watch glass according to claim 12, wherein the base region (31) has a first sub-region (311) and a second sub-region (312), wherein the space (70) of the watch glass recess (7) is defined by the first glass (1), the second glass (2), the first sub-region (311) and the second sub-region (312), wherein in particular the first sub-region (311) and/or the second sub-region (312) is/are inclined with respect to an axis (102) perpendicular to the glasses (1), (2).
14. A watch (100) comprising a watch glass (10) according to any one of the preceding claims.