EP2473884B1 - Decorative element for a wristwatch - Google Patents

Description

The present invention relates to a trim element for a wristwatch having at least one electronic function. More specifically, the present invention relates to a dressing element for a wristwatch having at least one electronic function totally autonomous with respect to the movement of the watch.

The present invention relates particularly but not exclusively to mechanical movement wristwatches. The users' attachment to purely mechanical watches is well known. Nevertheless, the mechanical watch wearers deprive themselves of the advantages that the electronic functions can bring them.

The document DE102004 014 788 describes a dial comprising a photovoltaic cell. A light source powered by said cell via a battery is positioned behind the dial. The document FR2538573 discloses a bezel comprising photovoltaic cells mounted in series photovoltaic series mounted.

The present invention aims to overcome this problem by providing a wristwatch with at least one electronic function whose operation is completely independent from that of the movement of the watch.

For this purpose, the present invention relates to a dial for a wristwatch, characterized in that at least one light source and a photovoltaic cell for supplying the light source with electrical energy are housed in the thickness of the dial so as to to form an autonomous electronic module totally independent of the movement of the wristwatch.

According to yet another characteristic of the invention, in the case where the power source comprises at least one photovoltaic cell, the photovoltaic cell supplies the electronic device via a rechargeable battery which stores the energy produced by the photovoltaic cell and restores it. when the electronic device is activated.

Thanks to these features, the present invention provides a wristwatch comprising one or more electronic devices whose operation is completely independent from that of the watch. This is particularly advantageous in the case of a mechanical wristwatch. Indeed, the watch retains the emotional aspect that gives it its purely mechanical operation while being joined one or more electronic devices that enrich the range of functions it can offer to its wearer. Of course, the present invention may equally well apply to an electromechanical or purely electronic watch provided that the electronic device or devices integrated in the trim element are independent of the movement of the watch.

According to an alternative embodiment, the invention also relates to a wristwatch bezel, characterized in that the bezel defines an interior volume in which are housed one or more photovoltaic cells mounted in series and at least one rechargeable battery as well as the least an electronic device.

• la figure 1 est une vue schématique en coupe d'une boîte de montre comprenant un cadran qui forme avec une cellule photovoltaïque, une batterie rechargeable et une source lumineuse un module électronique selon l'invention totalement indépendant du mouvement de la montre ;
• la figure 2 est une vue analogue à celle de la figure 1, une fonction de boussole électronique étant logée dans le cadran en plus de la fonction d'éclairage ;
• la figure 3 est une vue schématique en coupe d'une boîte de montre comprenant un cadran maintenu par un rehaut dans lequel sont intégrées une cellule photovoltaïque et une source lumineuse ;
• la figure 4 est une vue analogue à celle de la figure 3, la source lumineuse étant intégrée dans le cadran, au voisinage du pied du rehaut ;
• la figure 5 est une vue schématique en coupe d'une boîte de montre selon l'invention comprenant un cadran formé par une cellule solaire structurée sur un circuit imprimé et dans lequel est intégrée une source de lumière ;
• les figures 6A et 6B sont des vues respectivement en coupe et de dessus d'une lunette dans laquelle sont intégrés une cellule photovoltaïque, des super-condensateurs et une cellule d'affichage à cristal liquide pour former un module électronique complet et totalement autonome du mouvement de la montre ;
• les figures 7, 8 et 9 sont des vues schématiques en perspective illustrant trois moyens de commande différents d'un module électronique selon l'invention, et
• la figure 10 est une vue en plan d'une autre forme de réalisation d'un cadran de montre selon l'invention.

Other characteristics and advantages of the present invention will emerge more clearly from the following detailed description of various embodiments of a cladding element according to the invention, these examples being given purely by way of illustration and not limiting only in connection with one another. with the attached drawing in which:

• the figure 1 is a schematic sectional view of a watch case comprising a dial which forms with a photovoltaic cell, a rechargeable battery and a light source an electronic module according to the invention totally independent of the movement of the watch;
• the figure 2 is a view similar to that of the figure 1 an electronic compass function being housed in the dial in addition to the lighting function;
• the figure 3 is a schematic sectional view of a watch case comprising a dial held by a flange in which are integrated a photovoltaic cell and a light source;
• the figure 4 is a view similar to that of the figure 3 , the light source being integrated into the dial, in the vicinity of the foot of the flange;
• the figure 5 is a schematic sectional view of a watch case according to the invention comprising a dial formed by a solar cell structured on a printed circuit and in which is integrated a light source;
• the Figures 6A and 6B are views respectively in section and from above of a telescope in which are integrated a photovoltaic cell, super-capacitors and a liquid crystal display cell to form a complete and completely autonomous electronic module of the movement of the watch;
• the Figures 7, 8 and 9 are schematic perspective views illustrating three different control means of an electronic module according to the invention, and
• the figure 10 is a plan view of another embodiment of a watch face according to the invention.

The present invention proceeds from the general inventive idea of integrating into a wristwatch dial a light source as well as its power supply and control means. The integration of the light source must be done in such a way that the light source is completely autonomous with respect to the movement of the watch. It is thus possible to associate with a purely mechanical watch one or more electronic functions that expand the range of functions offered by the watch without harming the emotional nature of a mechanical watch. If the dial of the wristwatch is mounted removably, it is also possible to vary the functions offered by the watch. Of course, it is also possible to mount the dial according to the invention on an electromechanical watch, or even purely electronic. The only condition to be respected is that the dial forms an electronic module completely autonomous with respect to the movement of the watch. Different types of electronic devices such as one or more sources of ultraviolet radiation, a compass, an accelerometer or the like can be envisaged.

The figure 1 is a schematic sectional view of a watch case according to the invention. In what follows, the elements identical to those described in connection with a previous figure will be designated by the same reference numerals. Designated as a whole by the general numerical reference 1, the watch case according to the invention comprises a basic mechanical movement 2 above which is disposed a dial 4 covered by a lens 6. The movement 2 conventionally causes a switch 8 comprising an hour hand 10, a minute hand 12 and a seconds hand 14. For this purpose, the dial 4 has in its center a through hole 16 for the passage of the hour cannon 17.

According to the invention, at least one photovoltaic cell 18, for example made of monocrystalline silicon, is housed in the thickness of the dial 4. The electrical energy supplied by the photovoltaic cell 18 through the conversion of the incident natural light serves to supply one or more light sources 20 also housed in the thickness of the dial 4. There may be for example as many light sources 20 as there are index hours on the dial 4. These light sources 20 may For example, they are ultraviolet sources of the light-emitting diode type. The ultraviolet light produced by these diodes is reflected by the ice 6 and illuminates the hour hands 10, minutes 12 and seconds 14 which, for this purpose, will advantageously be covered with a layer of fluorescent or phosphorescent pigments. To improve the fluorescence or phosphorescence effect, the face of the ice 6 turned towards the dial 4 may be covered with one or several thin layers 22 reflecting the ultraviolet light and letting pass the largest amount of visible light spectrum.

The ultraviolet light produced by the light sources 20 is reflected by the lens 6 and is returned to the needles 10, 12, 14 to illuminate these needles. By fluorescence and phosphorescence effect, the pigments deposited on the surface of the needles produce a visible light that diffuses through the ice 6 of the watch.

The light source (s) 20 are fed directly or, preferably, via a rechargeable battery 24 by the photovoltaic cell 18. The rechargeable battery 24 may be formed by a button-cell, a film accumulator, super-capacitors or other . The rechargeable battery 24 is mounted on the rear face of the dial 4. It accumulates the electrical energy produced by the photovoltaic cell 18 and restores it to the light sources 20 on the user's command as explained in detail below. According to a variant not shown, the photovoltaic cell 18 can be replaced by a non-rechargeable battery.

As will be understood from the foregoing, the dial 4 forms, with its associated components, namely the photovoltaic cell 18, the rechargeable battery 24 and the light sources 20, a complete electronic module ensuring the illumination of the index hours and needles 10, 12 and 14 and which is completely autonomous with respect to the basic mechanical movement 2 of the watch according to the invention. The watch according to the invention therefore retains its purely mechanical aspect which confers its emotional character while being added an electronic function that offers its user a possibility of additional use. Of course, and according to a decisive advantage of the invention, the addition to the watch of an electronic function does not require any modification or adaptation of any kind of mechanical movement. At most it is necessary to slightly increase the height of the switch hours 10, minutes 12 and 14 seconds to account for the extra thickness of the dial 4 of the order of 1.0 to 1.5 millimeters.

The figure 2 is a view similar to that of the figure 1 on which we see that an additional electronic function for example of the compass type has been added. For this purpose, the photovoltaic cell 18 has been pierced with a hole to allow passage to a barrel 26 of a needle 28. This needle 28 is driven via its barrel 26 by a micromotor 30 mounted on the rear face of the dial 4 This micromotor 30 may be a microsystem better known by its Anglo-Saxon Micro Electronic Mechanical System or MEMS. It can also be a Lavet ultra flat motor, a piezoelectric motor or other. Other examples of additional electronic function can be envisaged such as an altimeter, a temperature sensor and more generally a sensor of a physical quantity.

The figure 3 is a schematic representation of another embodiment of the invention. According to this embodiment, the photovoltaic cell 18 is arranged annularly on the outer periphery of the dial 4 and is hidden from the viewpoint of the user by a semi-transparent flange 32 disposed obliquely, for example at 45 ° to to the normal to the dial 4. More specifically, the flange 4 lets the ambient light through its front face 32a turned on the side of the user so that the photoelectric effect can take place, but masks the photovoltaic cell 18 that the flare 32 covers by its rear face 32b. The light source or sources 20 are integrated in the inclined plane 34 of the flange 32.

The figure 4 is a schematic representation of an alternative embodiment of the embodiment of the invention illustrated in FIG. figure 3 . According to this variant, the photovoltaic cell 18 is arranged annularly along the outer periphery of the dial 4 and is hidden from the viewpoint of the user by a flange 32 of right cross section in the shape of a right triangle whose inclined plane 34 covers the photovoltaic cell 18. The inclined plane 34 of the flange 32 is disposed obliquely, for example at 45 ° relative to the normal to the dial 4. The flange 32 is semi-transparent: it lets the ambient light pass so that the photovoltaic effect can occur, but mask by diffusion the photovoltaic cell 18 so that it is invisible to the user. The light source or sources 20 which emit ultraviolet radiation are housed in the thickness of the dial 4, arranged near the base 36 of the flange 32. The ultraviolet light emitted by the light sources 20 is reflected by the ice 6 and is reflected back to the 10, minute 12 and second 14 hour hands. Excited by ultraviolet radiation, the phosphor and fluorine pigments emit light radiation in the wavelength range of the visible light passing through the ice cream 6.

The figure 5 is a schematic representation of yet another embodiment of the invention. According to this embodiment, the dial of the watch is constituted by the photovoltaic cell 18 itself which is structured on a printed circuit 38 which can be made of a ceramic or epoxy material for reasons of strength and rigidity. The wall sconces and other decorative motifs 40 are transferred to the visible surface of the photovoltaic cell 18 either by means of self-adhesive elements or by screen printing. The photovoltaic cell 18 is pierced with a through hole 42 for the passage of the barrel 17 of the hour hand 10. The photovoltaic cell 18 also has one or more cavities 44 in number corresponding to the number of light sources 20. The sources 20 are housed in these cavities 44. The dial formed by the photovoltaic cell 18 is held in place by an ordinary flange 46 which does not need to be semi-transparent. The flange 46 has a rectangle-shaped cross section and its inclined plane 48 forms with the normal to the surface of the photovoltaic cell 18 an angle of 45 °.

So far, the invention has been described in connection with a watch dial which forms with a photovoltaic cell, a rechargeable battery, one or more light sources and, if appropriate, a related function such as an electronic compass, an autonomous electronic module completely independent of the movement of the watch. Such a dial can equip any type of watch and, in particular, a mechanical watch, without any need to change the movement of the watch, so that the mechanical watch retains its intact emotional character while providing additional functions to his user. It goes without saying, however, that the dial according to the invention is not the only covering element to which the present invention can be applied and that other covering elements such as a telescope can also be transformed into a module. independent electronics according to the teachings of the present invention.

The Figures 6A and 6B are views respectively in section and from above of a bezel according to the invention generally designated by the general numerical reference 50. Of generally circular shape, the bezel 50 defines an interior volume in which are housed at least one photovoltaic cell 18 and a plurality of rechargeable batteries 52. More specifically, the photovoltaic cells 18 are preferably but not limited to three in number. Connected in series, the three photovoltaic cells 18 are mounted on a substrate 54 which is supported on an inner shoulder 56 of the telescope 50. The photovoltaic cells 18 are mounted close to the upper face 58 of the telescope 50, below this upper face 58. The upper face 58 of the telescope 50 is transparent or semi-transparent at least in the region where the three photovoltaic cells 18 are arranged.

Also included in the inner volume of the telescope 50 are two rings of rechargeable batteries 52 mounted on either side of a printed circuit 60. The rechargeable batteries 52 may for example be super-capacitors 52 which are components of the type mounted on the surface, better known under the name Anglo-Saxon Surface Mounted Device or SMD. The super-capacitors 52 of a ring are connected in parallel and the two rings of super-capacitors 52 are mounted in parallel. These two rings of super-capacitors 52 serve to store the electrical energy produced by the photovoltaic cells 18 and to restore it at the request of the user to power the electronic device or devices housed in the bezel 50. Of course, other types of rechargeable batteries such as shaped or film accumulators, superimposed or not, can be envisaged.

In the example shown in the drawing, the electronic device is a digital display device 59 such as a liquid crystal cell or a bistable cell which can, for example, be used to time an activity. The telescope 50 can be mounted fixed or rotating. It can also be removably mounted so as to be replaced by a bezel enclosing another electronic function.

In its simplified embodiment variant, the covering element according to the present invention comprises only a source of energy and an electronic device powered by this energy source. One can imagine that an electronic device such as a compass operates continuously being powered by one or more photovoltaic cells.

Nevertheless, according to the preferred embodiment of the invention, the electronic device or devices housed in a dial or bezel according to the invention are activated at the request of the user. For this purpose, it is necessary to provide control means for the electronic function. These control means can take different forms, three of which are shown in the drawing.

According to a first embodiment variant illustrated in figure 7 , the control means comprise a magnet 62 housed in the rotating bezel 50 and a reed contact 64 housed in the flange 46 of the dial 4. By rotating the rotating bezel 50, the magnet 62 is passed over the reed contact 64. The reed contact 64 detects the magnet 62 and generates a signal that is used to control the electronic device.

According to a second embodiment variant illustrated in FIG. figure 8 an electrode 66 forming a touch control key is structured in the flange 46.

According to a third variant embodiment, a switch 68 of the SMD type is mounted under the dial of the watch and is actuated by the user from outside the watch case by means of a push button 70 which passes through the middle part (not shown) of the watch case.

According to a variant not illustrated, the control means may be of the automatic type such as an accelerometer which, when it detects an acceleration caused by a movement of the arm of the user, will control the engagement of the electronic function.

It goes without saying that the present invention is not limited to the embodiments which have just been described and that various simple modifications and variants can be envisaged by those skilled in the art without departing from the scope of the present invention as defined. by the appended claims. Thus, it is conceivable to integrate one or more electronic functions in other trim elements than the dial or the bezel, such as, for example, the bracelet or a bracelet link or even the bottom of the watch.

The figure 10 is a perspective view of another embodiment of a watch face according to the invention. According to this embodiment, the hour indices of the dial 72 are formed by solar cells 74 arranged flush with the surface of the dial 72 and which supply light emitting diodes 76 arranged in the extension of said solar cells. These light-emitting diodes 76 are intended to illuminate by reflection on the ice 6 the hours, minutes and seconds hands.

Claims (15)

1. Dial for a wristwatch, characterized in that at least one light source (20) and one photovoltaic cell (18) for powering the light source (20) with electric energy are housed within the thickness of the dial (4; 72), so as to form an autonomous electronic module which is completely independent of the wristwatch movement.
2. Wristwatch dial according to claim 1, characterized in that the photovoltaic cell (18) powers the light source (20) via a rechargeable battery (24; 52).
3. Wristwatch dial according to claim 2, characterized in that the rechargeable battery (24) is mounted underneath the dial (4).
4. Wristwatch dial according to any of claims 1 to 3, characterized in that a hole is made in the photovoltaic cell (18) for the passage of a pipe (26) of a hand (18), which is driven, via the pipe (26), by a micromotor (30) mounted on the back surface of the dial (4).
5. Wristwatch dial according to any of claims 1 to 4, characterized in that the light source (20) is a source emitting an ultraviolet light which is reflected by a crystal (6) covering the dial (4) and which lights the hands (10, 12, 14), which move above the dial (4), the hands (10, 12, 14) being coated with a layer of fluorescent or phosphorescent pigments.
6. Wristwatch dial according to claim 5, characterized in that the surface of the crystal (6) which faces the dial (4) is coated with one or more layers (22), which reflect the ultraviolet light and allow the visible spectrum to pass through.
7. Wristwatch dial according to any of claims 1 to 6, characterized in that the hour symbols on the dial (72) are formed by solar cells (74), which are arranged flush with the surface of the dial (72) and which power light emitting diodes (76) arranged in the extension of the solar cells (74).
8. Wristwatch dial according to any of claims 1 to 6, characterized in that the photovoltaic cell (18) is arranged in an annular fashion along the external periphery of the dial (4) and is concealed from the user's view by a semi-transparent flange (32).
9. Wristwatch dial according to claim 8, characterized in that the flange (32) has a cross-section in the form of a right angled triangle and in that the light source (20) is arranged in proximity to a base (36) of the flange (32).
10. Wristwatch dial according to any of claims 1 to 6, characterized in that the photovoltaic cell (18) forms the watch dial, the light source (20) being housed in a cavity (44) arranged in the photovoltaic cell (18), the appliques and decorative designs (40) being added to the visible surface of the photovoltaic cell (18) by means of self-adhesive elements or by silk screen printing.
11. Bezel for a wristwatch, characterized in that the bezel (50) defines an internal volume, which houses one or more series connected photovoltaic cells (18) and at least one rechargeable battery (52) and at least one electronic device (59).
12. Wristwatch bezel according to claim 11, characterized in that there are three series connected photovoltaic cells (18), and in that the rechargeable battery is formed by two rings of supercapacitors (52), the supercapacitors of one ring being mounted in parallel and the two rings being mounted in parallel on both sides of a printed circuit (60).
13. Dial or bezel for a wristwatch according to any of claims 1 to 12, characterized in that at least one control element for the electronic device is integrated in said dial or said bezel.
14. Dial or bezel for a wristwatch according to claim 13, characterized in that the control element is formed either by a magnet (62) and a reed contact (64), or by an electrode forming a touch sensitive button, or by a surface mounted device switch controlled by a push-button (70), or by an automatic element.
15. Dial or bezel for a wristwatch according to claim 14, including a flange (46), characterized in that the magnet (62) is housed in the bezel (50) and in that the reed contact (64) is housed in the flange (46), or in that the electrode (66) is structured on the surface of the flange (46).

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