CH715017B1 - Watch comprising an element provided with an illuminable index. - Google Patents

Abstract

The invention relates to a watch (1) comprising a watch case provided with a middle part, the middle part carrying an element (4) provided with at least one index and defining an internal cavity (8). According to the invention, the watch (1) further comprises at least one pair of electrodes (10a, 10b) and at least one light source device (12) connected to the pair of electrodes (10a, 10b) and arranged opposite the index, the electrodes (10a, 10b) of the pair of electrodes being fixed in the internal cavity (8), the element (4) being permeable to water so that, when the watch ( 1) is immersed in seawater (15), seawater (15) can enter the inner cavity (8), so that the pair of electrodes (10a, 10b) and the seawater (15) form an electrochemical cell, to power said light source device (12).

Description

TECHNICAL FIELD OF THE INVENTION

The invention relates to a watch comprising a watch case provided with a middle part, the middle part carrying an element provided with at least one lightable index.

[0002] The watch is configured to be able to be immersed in sea water, such as for example a diver's watch.

STATE OF THE ART

[0003] In the field of watches comprising a watch case provided with a middle part, it is known to provide on the middle part an element provided with at least one luminous index. In the case of a diver's watch, the element is for example a rotating bezel, and the index makes it possible, for example, to indicate a reference position for the measurement, by the diver, of his immersion time at sea. To do this, the diver turns the bezel so as to align the index with the minute hand. This position then becomes the reference for measuring the elapsed time. One of the main efficiency criteria of a diver's watch must be the readability of the time and the index during the immersion phase.

[0004] In order to meet this constraint, a known solution consists in covering the index of the bezel, as well as the hands of the watch, with a phosphorescent material. This makes the index and hands visible in low light conditions, typically a few meters underwater. Such a diver's watch is for example described in the patent application FR 1 572 837 A. However, a disadvantage of this solution is that it requires the phosphorescent elements to be charged beforehand in sunlight or from a source of artificial light, so that the latter can then emit, for a period limited to a few hours and in decreasing fashion (type of phosphorus, quantity, duration and intensity of the charge before diving), light in a dark environment, for example under the 'water.

[0005] Wristwatches comprising a dial provided with several luminous indexes are also known, allowing information located on the dial to be read in the dark as well as in broad daylight.

[0006] Such a wristwatch is for example described in patent application WO 2016146350 A1. The wristwatch includes a watch case, a rotating bezel mounted on the watch case and a dial with several luminous hour markers. The luminous indexes are illuminated through the dial by a light source arranged under the dial and powered by a source of electrical energy such as a battery or a rechargeable accumulator. A component for activating the light source is housed in the rotating bezel and cooperates with a detection component housed in the watch case. Thus, the user can control the switching on of the light source by pivoting the rotating bezel and bringing it into a predetermined position in which the presence of the activation component is detected by the detection component which, in response , controls the switching on of the light source; the bezel acts there as a switch. However, when the source of electrical energy is exhausted, it is necessary to replace the latter or to manually recharge it, which is restrictive for the user.

SUMMARY OF THE INVENTION

[0007] The object of the invention is therefore to provide a watch making it possible to illuminate the index finger in low light conditions, in particular under water, while being easy to use, and requiring neither prior charging of phosphorescent elements or manual replacement or recharging of a source of electrical energy.

[0008] To this end, the invention relates to a watch which comprises the characteristics mentioned in independent claim 1.

[0009] Particular shapes of the watch are defined in dependent claims 2 to 20.

An advantage of such a watch according to the invention resides in the use of a pair of electrodes fixed in an internal cavity of the element and of a light source device connected to the pair of electrodes and arranged next to the index finger. The element is water permeable so that when the watch is submerged in seawater, seawater can enter the interior cavity. The pair of electrodes and the sea water thus form an electrochemical cell. In this way, when the watch is submerged, sea water enters the volume between the electrodes, allowing the battery thus formed to start operating and to power the light source device. This offers a particularly simple solution for illuminating the index finger in low light conditions underwater, without the need for manual replacement or recharging of an electrical power source. In addition, the index lights up and remains lit as soon as the watch is submerged, without the user having to press any particular buttons or controls.

[0011] According to a preferred embodiment of the invention, the element is an annular bezel rotatably mounted around the middle part, the bezel defining an interior cavity opening out on the outside of the watch case. The pair of electrodes and the light source device are preferably integral with the annular bezel, so as to be able to rotate around the middle part at the same time as the bezel.

[0012] Advantageously, the watch further comprises a mechanical element for separating the two electrodes of the pair of electrodes. This prevents any physical contact between the electrodes.

[0013] Advantageously, the watch comprises several pairs of electrodes of opposite polarity, the pairs of electrodes being interconnected in series. This makes it possible, for example when the light source device comprises at least one light-emitting diode, to more easily reach the threshold voltage of the latter in order to be able to turn it on.

[0014] According to a particular technical characteristic of the invention, the light source device comprises at least one light-emitting diode.

[0015] Advantageously, the light-emitting diode is coated in a protective resin able to electrically insulate the light-emitting diode from the water. This makes it possible to protect and electrically isolate the light-emitting diode with respect to water.

[0016]Also advantageously, the light-emitting diode is arranged in the internal cavity of the element, under the index. This particular configuration makes it possible to effectively illuminate the index when the watch is immersed in seawater.

[0017] According to a particular technical characteristic of the invention, the index is formed of an opening made in the element, said opening being provided with a window capable of letting light through. Preferably, the window is made of sapphire.

[0018] Advantageously, at least one of the free surfaces of the sapphire is frosted. This makes it possible to better diffuse the light emitted by the light source device and to increase the viewing angle of the illuminated index.

According to a particular embodiment of the invention, the electrodes of the pair of electrodes are chosen so that the pair of electrodes and the sea water form a Leclanché type electrochemical cell. This particular embodiment has the advantage of obtaining improved electrical power for the electrochemical cell.

According to another particular embodiment of the invention, the electrodes of the pair of electrodes are chosen so that the pair of electrodes and the sea water form an electrochemical cell of the metal/air type. This particular embodiment has the advantage of obtaining a high energy density for the electrochemical cell.

[0021] Advantageously, an anode of the pair of electrodes consists of a metallic material chosen from the group consisting of aluminium, zinc and magnesium. Such materials have the advantage of being very energetic. Thus, if the cell dries out quickly and thus becomes inactive between two successive immersions, the corrosion of the anode will not have time to significantly affect the galvanic performance of the cell.

[0022] Advantageously, an inner wall of the inner cavity is coated with a layer of a water-soluble salt. This offers the advantage that the watch can also be used in a freshwater environment. Indeed the salt, combined with the fresh water in which it is dissolved, then forms an electrochemical cell with the pair of electrodes.

[0023] Advantageously, the watch further comprises an external actuator and an additional light source device arranged in the watch case opposite a dial of the watch, the external actuator and the additional light source device being connected to the pair of electrodes. This makes it possible, by making contact on the electrodes via the actuation of the external actuator, to also power the additional light source device, and thus to illuminate, in addition to the index, the dial and the hands of the show.

BRIEF DESCRIPTION OF FIGURES

The aims, advantages and characteristics of the watch according to the invention will appear better in the following description on the basis of at least one non-limiting embodiment illustrated by the drawings in which: Figure 1 is a top view of a watch according to a preferred embodiment of the invention, the watch comprising an annular bezel provided with an index; FIG. 2 is a schematic view of the inside of the watch of FIG. 1, the watch comprising a light-emitting diode and two cells in series each comprising a pair of electrodes; Figure 3 is a schematic representation of the watch of Figure 2; FIG. 4 is a cross-sectional view, taken along a section plane IV-IV, of the watch of FIG. 2 according to a first variant embodiment, in an off state of the light-emitting diode; Figure 5 is a view similar to that of Figure 4, in an on state of the light emitting diode; and FIG. 6 is a cross-sectional view, taken along a section plane VI-VI, of the watch of FIG. 2 according to a second variant embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a watch 1 provided with a watch case 2. The watch case 2 comprises a middle part, such a middle part not being shown in the figures for reasons of clarity. The middle carries an element 4. The element 4 is provided with at least one index 6 and defines an interior cavity 8, such an interior cavity 8 being visible in Figures 2 and 4 to 6.

In the preferred embodiment illustrated in Figures 1 to 6, the element 4 is an annular rotating bezel rotatably mounted around the caseband. In the illustrative example of Figure 1, the watch 1 is a diver's watch and the rotating bezel 4 has a single index 6. The index 6 is an illuminable index and makes it possible to constitute a reference position for example for measurement, by the diver, of his immersion time in the water. However, the present invention is in no way limited to a diver's watch comprising an annular rotating bezel, but applies more generally to any watch comprising a middle part carrying an element provided with at least one index and defining an internal cavity or any watch component having a cavity associated with such an index.

[0027] The index 6 is for example formed by an opening formed in the element 4. The opening is preferably closed by a closing element or window able to let the light pass. Preferably, the window is made of sapphire. Preferably again, at least one of the free surfaces of the window, in this case the sapphire, is frosted.

As shown in Figures 2 and 3, the watch 1 further comprises at least one pair of electrodes 10a, 10b and at least one light source device 12 connected to the pair of electrodes 10a, 10b. In the illustrative example of FIGS. 2 and 3, watch 1 comprises two pairs of electrodes 10a, 10b and a single light source device 12. Preferably, watch 1 also comprises a mechanical element 14 for separating the two electrodes 10a, 10b of each pair of electrodes. Such a mechanical element 14 is visible in Figures 4 to 6.

[0029] Preferably again, the watch 1 can also comprise, according to a variant, an external actuator and an additional light source device; such elements not being visible in the figures for reasons of clarity. The external actuator is for example formed of a push button. The additional light source device is for example arranged in the watch case 2 opposite a dial of the watch. The external actuator and the additional light source device are connected to the pair of electrodes 10a, 10b.

[0030] The element 4 is arranged on the watch case so that water can enter the interior cavity 8 and is therefore permeable to water. To do this, the interior cavity 8 opens out through at least one orifice, for example, as illustrated in FIGS. 4 to 6, the element 4 is arranged on the caseband of the watchcase 2 so as to define an opening towards the outside, which opening is in fluid communication with the interior cavity 8. In the illustrative example of FIG. 1 where the element 4 is an annular rotating bezel, the rotating bezel 4 is for example clipped onto the middle part by covering this last, and by defining, for example with the middle part, a substantially circular opening, in fluid communication with the inner cavity 8. The opening is in this case located between the inner outer periphery of the bezel 4 and the outer rim of the middle part .

Alternatively, the inner cavity 8 is connected to the outside of the bezel by an orifice 8a made in a wall of the bezel and through which a liquid can easily enter. Preferably the inner cavity 8 is connected to the outside by at least two orifices which allow circulation of liquid in said cavity.

The electrodes 10a, 10b are fixed in the inner cavity 8. In this way, and since the element 4 is permeable to water, sea water can enter the inner cavity 8 when the watch 1 is immersed in sea water, and thus come into contact with the electrodes 10a, 10b. The pair(s) of electrodes 10a, 10b and the sea water then form an electrochemical cell intended to electrically supply the light source device 12, as will be described in more detail below. Rich in salt and ions, seawater acts as an electrolyte which activates an oxidation-reduction reaction at the electrodes. The electrodes 10a, 10b are held mechanically in the interior cavity 8 so as to never come into contact with each other or with the surface of the rotating bezel 4.

In the illustrative example of Figures 2 and 3 in which the watch 1 comprises two pairs of electrodes 10a, 10b, each pair of electrodes comprises an electrode 10a of positive polarity, also called cathode; and an electrode 10b of negative polarity, also called an anode. Each pair of electrodes 10a, 10b forms a current-generating cell 18, the two cells 18 being connected together in series, as illustrated in FIG. 2 as well as in the equivalent circuit of FIG. 3. More precisely, the anode 10b of a first pair of electrodes is connected to cathode 10a of a second pair of electrodes. The cathode 10a of the first pair of electrodes and the anode 10b of the second pair of electrodes are connected to respective terminals of the light source device 12. As visible in FIG. 2, the electrodes 10a, 10b are cut in the shape of the rotating bezel 4. In a variant not shown, the number of pairs of electrodes 10a, 10b connected together in series can be chosen to be greater than or equal to three.

According to a first variant embodiment illustrated in Figures 4 and 5, the two electrodes 10a, 10b of each pair of electrodes each have a planar geometry and extend parallel to each other, facing each other. opposite each other in the interior cavity 8. According to this first variant embodiment, the mechanical element 14 for separating the two electrodes 10a, 10b is for example formed of a fabric membrane. The fabric membrane is for example arranged between the two electrodes 10a, 10b of each pair of electrodes. When watch 1 is immersed in seawater 15, the volume between electrodes 10a, 10b fills with seawater 15. The electrochemical cell formed by electrodes 10a, 10b and seawater 15 then in function via an oxidation-reduction reaction occurring between the electrodes 10a, 10b and the sea water 15. The light source device 12 then changes from an off state, represented in FIG. on state, shown in Figure 5.

According to a second alternative embodiment illustrated in FIG. 6, the two electrodes 10a, 10b of each pair of electrodes each have a cylindrical geometry. The two electrodes 10a, 10b of each pair of electrodes are arranged concentrically in the interior cavity 8. For example, the cathode 10a of each pair of electrodes, formed of a metal sheet, surrounds the anode 10b of this same pair of electrodes. In a variant not shown, the anode 10b of each pair of electrodes can surround the cathode 10a of this same pair of electrodes. According to this second variant embodiment, the mechanical element 14 for separating the two electrodes 10a, 10b is for example formed of a membrane permeable to ions. The ion-permeable membrane is for example arranged between the two electrodes 10a, 10b of each pair of electrodes, and thus ensures the spacing between the two electrodes 10a, 10b. The operation of watch 1 according to this second variant embodiment is analogous to that of watch 1 according to the first variant embodiment, seawater filling the volume between the two concentric electrodes 10a, 10b.

[0036] Preferably, an inner wall of the inner cavity 8 is coated with a layer of a water-soluble salt, such a layer of salt not being shown in the figures for reasons of clarity. This also makes it possible to use the watch according to the invention in a fresh water environment.

The light source device 12 is arranged opposite the index 6, thus allowing the illumination of the index 6. Preferably, as shown in Figures 2, and 4 to 6, the source device light 12 is integral with the rotating bezel 4. More preferably, the light source device 12 comprises at least one light emitting diode 16. In the illustrative example of Figures 2 to 6, the light source device 12 comprises a single light-emitting diode 16. The light source device 12 may further comprise a resistor connected in series with the light-emitting diode 16. Such a resistor, not shown in the figures, is intended to limit the current flowing within the light-emitting diode 16 and thereby protect the latter. This makes it possible to guarantee a constant current in the circuit of the light-emitting diode 16.

The light-emitting diode 16 is preferably coated in a protective resin capable of electrically insulating the light-emitting diode 16 from the water. Such a protective resin is not shown in the figures for reasons of clarity. The light-emitting diode 16 is for example arranged in the interior cavity 8 of the element 4, under the index 6 so as to be able to illuminate the latter. The threshold voltage of the light-emitting diode is for example between 2.6 V and 3 V.

Several particular embodiments will now be described for the electrodes 10a, 10b.

According to a first particular embodiment, one of the electrodes of the pair of electrodes 10a, 10b is a zinc electrode, and the other electrode of the pair of electrodes 10a, 10b is a copper electrode. According to this particular embodiment, seawater is reduced to produce hydrogen. The oxidation-reduction reaction which occurs between the electrodes 10a, 10b and the sea water generates an ionic current in the volume of water penetrated into the cavity 8 of the bezel 4, as well as a transport of electric charges corresponding to the current required to supply the light source device 12. The battery thus formed according to this first particular embodiment typically has an open circuit voltage of the order of 0.5 V.

According to a second particular embodiment, the electrodes 10a, 10b of the pair of electrodes are chosen so that the pair of electrodes 10a, 10b and the seawater form a Leclanché type electrochemical cell. . According to this particular exemplary embodiment, seawater only plays the role of electrolyte. The cathode 10a of the pair of electrodes comprises for example a manganese oxide deposited on a metal sheet. The battery thus formed according to this second particular embodiment typically has an open-circuit voltage of the order of 1.5 V; and produces a current for example of the order of 10 mA/g of manganese oxide.

According to a third particular embodiment, the electrodes 10a, 10b of the pair of electrodes are chosen so that the pair of electrodes 10a, 10b and the seawater form a metal-type electrochemical cell. /air. According to this particular embodiment, the oxygen dissolved in the sea water is reduced. The anode 10b of the pair of electrodes is for example made of a metallic material. The metallic material is preferably aluminum. As a variant, the metallic material can also be zinc, or even magnesium. The cell thus formed according to this third particular embodiment typically has an open circuit voltage of the order of 1.5 V. In this third particular embodiment, it is necessary to ensure good convection of the water in the sea within the watch to renew the oxygen consumed, which can be done by optimizing the number and shape of the openings in contact with the outside of the bezel.

The previous description of the watch according to the invention was made with reference to an element provided with a single index and defining a single internal cavity; and with reference to a single light source device. However, those skilled in the art will understand that the invention applies in the same way to watches comprising a plurality of indexes, interior cavities, pairs of electrodes and light source devices each associated respectively with a index.

[0044] It will also be noted that the light source device according to the invention is energetically autonomous so that it can equip both a watch comprising a mechanical movement and a watch comprising an electronic or hybrid movement.

[0045] Finally, the use of an LED as the preferred light source for signaling the diving index advantageously makes it possible to choose the color of the latter, because the color range of LEDs covers a wide palette unlike phosphorescent materials. which are always orange, green or light blue. A person who usually dives in blue water will benefit from choosing a yellow LED in order to have maximum contrast. Similarly, a person who usually dives in greenish water can advantageously choose a red LED.

Claims (22)

1. Watch (1) comprising a watch case (2) provided with a middle part, the middle part carrying an element (4) provided with at least one index (6) and defining an internal cavity (8); characterized in that the watch (1) further comprises at least one pair of electrodes (10a, 10b) and at least one light source device (12) connected to the pair of electrodes (10a, 10b) and arranged facing the index (6), the electrodes (10a, 10b) of the pair of electrodes being fixed in the internal cavity (8), the element (4) being permeable to water so that, when the watch (1) is immersed in seawater (15), seawater (15) can enter the inner cavity (8), so that the pair of electrodes (10a, 10b ) and sea water (15) form an electrochemical cell, to power said light source device (12). 2. Watch (1) according to claim 1, characterized in that the element (4) is an annular bezel rotatably mounted around the middle part, the bezel (4) defining the inner cavity (8) opening to the outside of the watch case (2). 3. Watch (1) according to claim 2, characterized in that the two electrodes (10a, 10b) of the pair of electrodes each have a planar geometry and extend parallel to one another, facing each other. opposite in the inner cavity (8) of the bezel (4). 4. Watch (1) according to claim 2, characterized in that the two electrodes (10a, 10b) of the pair of electrodes each have a cylindrical geometry and are arranged concentrically in the inner cavity (8) of the bezel (4), a first electrode (10a) formed of a metal foil surrounding a second electrode (10b). 5. Watch (1) according to any one of the preceding claims, characterized in that it further comprises a mechanical element (14) for separation and/or electrical insulation of the two electrodes (10a, 10b) of the pair of electrodes. 6. Watch (1) according to claim 5 when it depends on claim 3, characterized in that the mechanical separation element (14) is formed of a fabric or polymer membrane. 7. Watch (1) according to claim 5 when dependent on claim 4, characterized in that the mechanical separation element (14) is formed of a membrane permeable to ions. 8. Watch (1) according to any one of the preceding claims, characterized in that it comprises several pairs of electrodes (10a, 10b) of opposite polarities, the pairs of electrodes (10a, 10b) being interconnected serial. 9. Watch (1) according to any one of the preceding claims, characterized in that the light source device (12) comprises at least one light-emitting diode (16). 10. Watch (1) according to claim 9, characterized in that the light-emitting diode (16) is coated in a protective resin capable of electrically insulating the light-emitting diode (16) from the water. 11. Watch (1) according to claim 9 or 10, characterized in that the light-emitting diode (16) is arranged in the internal cavity (8) of the element (4), under the index (6). 12. Watch (1) according to any one of the preceding claims, characterized in that the index (6) is formed by an opening made in the element (4), said opening being provided with a window capable of let the light through. 13. Watch (1) according to claim 12, characterized in that the window is made of sapphire. 14. Watch (1) according to claim 13, characterized in that at least one of the free surfaces of the sapphire crystal is frosted. 15. Watch (1) according to any one of the preceding claims, characterized in that a first electrode of the pair of electrodes is a zinc electrode, and a second electrode of the pair of electrodes is a copper electrode . 16. Watch (1) according to any one of claims 1 to 14, characterized in that the electrodes (10a, 10b) of the pair of electrodes are chosen so that the pair of electrodes (10a, 10b ) and seawater (15) form a Leclanché type electrochemical cell. 17. Watch (1) according to claim 16, characterized in that a cathode (10a) of the pair of electrodes comprises a manganese oxide deposited on a metal foil. 18. Watch (1) according to any one of claims 1 to 14, characterized in that the electrodes (10a, 10b) of the pair of electrodes are chosen so that the pair of electrodes (10a, 10b ) and sea water (15) form a metal/air type electrochemical cell. 19. Watch (1) according to claim 18, characterized in that an anode (10b) of the pair of electrodes consists of a metallic material chosen from the group consisting of aluminium, zinc and magnesium. . 20. Watch (1) according to any one of the preceding claims, characterized in that it comprises a plurality of indexes, internal cavities, pairs of electrodes and light source devices each associated respectively with an index . 21. Watch (1) according to any one of the preceding claims, characterized in that an interior wall of the interior cavity (8) is coated with a layer of a water-soluble salt. 22. Watch (1) according to any one of the preceding claims, characterized in that the watch (1) further comprises an external actuator and an additional light source device arranged in the watch case facing a dial of the watch, the external actuator and the additional light source device being electrically connected to the pair of electrodes.