CH701301A2 - Timepiece i.e. electronic wristwatch, has light source housed in interior volume of watch case and producing light that passes through transparent or translucent portion such as middle, of corresponding casing element - Google Patents

Abstract

The timepiece has casing elements constituted of a back cover (2), a middle (1), an opaque dial (3), watchstrap strands, and a bezel (26), where one of the elements is made of transparent/translucent material. The cover, the middle and the bezel define interior volume (4) of a watch case (6) to house a clock movement (M). A light source (10) i.e. LED, is housed in the interior volume, and produces light that passes through a transparent/translucent portion such as middle, of the corresponding casing element. A decorative sheet is arranged above a light guide i.e. optical fiber, of the strands. The transparent or translucent material is chosen from a group comprising plastic material, ceramic material, sapphire and fused silica. The light guide is overmolded in a layer made of silicone or polyurethane. The decorative sheet is made of polymethyl methacrylate.

Description

The present invention relates to a timepiece with special aesthetic effects. More specifically, the present invention relates to a timepiece with original play of light.

[0002] The creation of timepieces such as wristwatches having an improved aesthetic appearance is a constant concern for watchmakers and especially for those responsible for designing the various trim elements. It would be too long to list here all the solutions that have been envisaged to impart to a timepiece as neat and aesthetic as possible. By way of example only, there can be mentioned the guilloche technique of the dials, the shape and / or the color of the dial or needle appliques or even the addition of precious or semi-precious stones.

The present invention is part of the quest to provide customers with watches whose appearance is both aesthetic and surprising.

For this purpose, the present invention relates to a timepiece comprising, in addition to an ice, at least the following trim elements: a bottom, a caseband, a dial, a bezel and two strands of bracelet at least one of these covering elements being at least partially transparent or translucent, the bottom, the caseband and the bezel defining an interior volume in which a watch movement is housed, the timepiece being characterized in it comprises at least one light source housed in the interior volume and producing a light which passes through the transparent or translucent part of the covering element concerned.

With these features, the present invention provides a timepiece whose aesthetic appearance can be varied virtually to infinity. The light source being housed in the interior volume of the watch case, it may for example be envisaged that the caseband is partially or totally transparent, so that the light produced by the light source diffuses through said middle part. Similarly, it may be envisaged to illuminate the appliques at the level of the dial of the watch. For this purpose, the dial can be provided completely opaque and let the light escape only at the appliques. It is also possible to cover a transparent dial with an opaque mask, which also only lets out the light at the appliques.

Different modes of escape of the light can be provided. According to a simplified variant embodiment of the invention, the light produced by the light source directly illuminates the transparent or translucent areas of the trim element (s) through which it is desired for the light to come out. This embodiment is applicable when no obstacle is interposed between the light source and the dressing element to be illuminated.

According to a second variant embodiment, the light source is a light-emitting diode or LED which emits ultraviolet, violet, blue, white or infrared light and the covering element is made of a plastic material loaded with fluorescent and / or phosphorescent particles. In this way, the fluorescent and / or phosphorescent particles absorb the emitted radiation and re-emit a homogeneous visible light. Depending on the type of particles selected, fluorescent and / or phosphorescent, the light effect ceases immediately after extinction of the light source or on the contrary continues with the effect of remanence.

According to a third embodiment, the light produced by the light source is injected into a light guide which then brings the light at the transparent or translucent or areas of the dressing elements considered. According to one variant, the light guide is an optical fiber that makes it possible to circumvent any obstacles that may arise between the light source and the transparent or translucent zone of the considered covering element through which the light will escape. the interior volume of the watch case. The optical fiber may be an optical fiber that diffuses the injected light along its entire length.

Preferably, the light source is a light emitting diode or LED mounted on a support circuit board type print or PCB together with its electronic control circuit. The light source is powered for example by an interchangeable or rechargeable battery or by a solar cell.

Where the light must not pass, the dressing element concerned may be opaque in the mass or be coated with a layer of opaque paint.

Other features and advantages of the present invention will emerge more clearly from the following detailed description of various embodiments of the invention, these examples being given for purely illustrative and non-limiting purposes only in connection with the accompanying drawings. on which: <tb> - fig. 1 <sep> is a sectional view of a watch case equipped with a light source according to the invention; <tb> - fig. 2 <sep> is a partial sectional view of a middle watch according to the invention in the region of a push button; <tb> - fig. 3A <sep> is a top view of a watch caseband along the inner side of which is fixed a diffusing optical fiber in which is injected light; <tb> - fig. 3B <sep> illustrates a bundle of optical fibers in which is practiced a V-notch opposite the light source for an optimization of the efficiency at the injection of light into the optical fibers; <tb> - fig. 3C <sep> illustrates a bundle of optical fibers cut at a location of its perimeter to be able to insert a light source into the space left vacant; <tb> - figs. 3D to 3F <sep> illustrate a bundle of optical fibers provided with a plurality of optical extractors which are respectively in the form of V-grooves, microlenses or small printed surfaces, the density of these optical extractors being as much as they are far from the source of light; <tb> - fig. 4 <sep> is a top view of a wristwatch comprising a dial through which the light passes; <tb> - fig. 5A <sep> is a top view of a wristwatch comprising two strands of bracelet in which the light diffuses; <tb> - fig. 5B <sep> is a view similar to that of FIG. 5A, the transparent parts placed at the places where the strands of the bracelet are attached to the middle part having a conical shape; <tb> - fig. 5C <sep> is a view similar to that of FIG. 5A, the transparent parts placed at the places where the strands of the bracelet are attached to the middle part being constituted by two straight sections of a bar of optical fibers; <tb> - fig. 6 <sep> is a sectional view of a digital display watch case, and <tb> - fig. 7 <sep> is a longitudinal sectional view of a bracelet strand comprising a light guide in which the light diffuses.

The present invention proceeds from the general inventive idea of housing at least one light source in the interior volume of a watch case, the light produced by the light source can escape to the outside of the watch case by at least one watch element of the watch intended to be at least partially transparent or at least translucent. This provides a timepiece with original aesthetic effects having an extremely attractive appearance in the dark or dark.

Figure 1 is a sectional view of a middle part 1 defining with a bottom 2 and a dial 3 an interior volume 4 of a watch case 6. For the purposes of this description, it will be imagined that the watch is an electronic watch and that its movement M is arranged in the bottom of the watch case 6. In this way, it is possible to have above the movement M a support plate 8 of the printed circuit board or PCB type on which are mounted a light source 10 for example of the LED type or LED and its electronic control circuit 12. The light source 10 is fed for example by a rechargeable battery 14 or interchangeable and conventionally arranged under the watch movement M on the bottom side 2 of the watch case 6. It will be understood that the watch according to the invention can be electronic, electromechanical or even purely mechanical. In the latter case, it will be sufficient to provide a housing for receiving a battery which will be intended to supply only the light source 10 and its electronic control circuit 12. Thus, the present invention can be applied to any type of wristwatch, the the only constraint to be respected is that there is no obstacle to the propagation of light between the light source and the trim element through which said light must go out.

According to one embodiment of the invention illustrated in FIG. 2, a crown of light is created around a control member of the watch such as a push-button 16. If the middle part 1 is metallic, there is practiced in the latter a through-hole 18 in which a cylinder 20 is engaged. transparent or at least translucent that will serve as a light guide for the light that escapes from the watch case 6. It will be understood that to obtain the desired effect, namely to form a crown of light around the head of the button -poussoir 16, it is necessary that the outer diameter of the transparent or translucent cylinder 20 is greater than the outside diameter of the head of the push button 16.

In addition to its light guide function, the cylinder 20 can also serve as a mechanical guide for the pushbutton 16. Of course, it is also possible to introduce into the cylinder 20 an insert that will serve as a mechanical guide to the button. 16. If the case 1 is made of a transparent or translucent material such as a plastic material, a ceramic material, sapphire or fused silica, it may be colored in the mass except in a region surrounding the button. pusher 16 where the material remains transparent or translucent. It is also possible, to simplify the injection method of the plastic case 1, to tint the latter in the mass in all its volume, then to machine a through hole in which is engaged a transparent or translucent cylinder as explained above in connection with a metal middle. Yet another solution is to make the caseband 1 by injection of a transparent plastic material, then to coat the inner face of this case with a layer of light-absorbing material except in the region surrounding the push-button 16. To vary the effects in particular in the vicinity of the push button 16, it is also possible to overmould a transparent or translucent plastic material on the dressing element considered made of an opaque material.

Any type of light source such as incandescent lamp, light emitting diode, organic electroluminescent diode or other can be used. In a particular embodiment of the invention, a light-emitting diode emitting ultraviolet, violet, blue, white or infrared light is used in combination with a middle part made of plastic material loaded with fluorescent and / or phosphorescent particles. In this way, the fluorescent and / or phosphorescent particles absorb the radiation emitted by the diode and reemit a homogeneous visible light. Depending on the type of particles selected, fluorescent and / or phosphorescent, the light effect ceases immediately after extinction of the light source or on the contrary continues with the effect of remanence.

The covering element or elements of the watch that let all or part of the light produced by the light source can be illuminated directly by this light source. These elements of dressing can nevertheless be also illuminated indirectly by the light source. By way of example, FIG. 3 shows a middle part 1 made of plastic material along the inner side of which has been fixed a light guide 22 which makes it possible to bring the light from the point where it is injected into the guide 22 to the level of the transparent or translucent zone or zones of the considered covering element or elements by which the light will escape from the interior volume 4 of the watch case 6. According to a variant, the light guide 22 is an optical fiber or a bundle of such optical fibers which makes it possible to circumvent any obstacles that may arise between the light source 10 and the transparent or translucent zone of the considered covering element through which the light will escape from the interior volume 4 of the watch case 6. As illustrated in FIG. 3, the optical fiber may be an optical fiber that diffuses the injected light over its entire length. The light guide may also be a transparent plastic ring and section for example round or circular.

According to a first variant embodiment (FIG 3B), a notch 54 in V facing the light source 10 is practiced in the light guide 22 .The angle formed by the two arms 54a and 54b of the notch 54 is adjusted according to the light emission cone of the light source 10 to ensure optimum efficiency in the injection of light into the light guide 22 such as a bundle of optical fibers.

According to a second embodiment variant illustrated in FIG. 3C, the light guide 22 is cut at a location 56 of its perimeter and the light source 10 is inserted into the space left vacant between the facing ends 22a, 22b of the light guide 22. Preferably, for the optical coupling between the light source 10 and the light guide 22, the gap is filled between the light source 10 and the end 22a of the light guide 22 which serves as the input face of the latter by means of an element optical coupling 57 formed of an optical gel such as a silicone. It is thus possible to guarantee optimum efficiency when light is injected into the light guide 22.

The rays of light propagating inside the light guide 22 at angles less than the limit reflection angle are reflected totally in the light guide 22. To extract the light from the light guide 22, this light guide 22 is provided with a plurality of optical extractors 58. Depending on the circumstances (see Fig. 3D-3F), these optical extractors 58 may be in the form of V-shaped grooves 60 machined in the surface. the light guide 22 or even microlenses 62 distributed on the surface of the light guide 22. The optical extractors 58 can also be formed by small printed surfaces 64 carried on the surface of the light guide 22. The optical extractors 58 can still be formed by pigment particles embedded in the light guide 22. These particles act as so many scattering centers and light extraction. Advantageously, the optical extractors (grooves 60, microlenses 62, pigment particles or the like) can be manufactured simultaneously with the light guide 22 by injection of a material, for example a plastic material. It will be noted that in order to optimally homogenize the density of the light that escapes from the light guide 22 all along the perimeter of the latter, it is possible to vary the density of the optical extractors 58 (grooves 60, microlenses 62 , pigment particles or other), this density being even greater than the extractors are remote from the point of injection of light in the light guide 22.

So far, the present invention has been described in connection with the middle part as the sole element of dressing. It should be understood that the invention is not limited to this single embodiment and that it applies similarly to the other elements of dressing of the watch that are the bottom, the dial, the bezel, the flare , the strands of the bracelet and others. Thus, as shown in FIG. 4, one can for example illuminate the appliques 24 at the bezel 26 and the dial 3. To this end, the bezel 26 and the dial 3 can be provided totally opaque and let out light at the level of the appliques 24. It is also conceivable to make the bezel 26 and the dial 3 of a material, for example plastic, transparent or translucent and then to cover them with a mask in an opaque color which, too, only lets out the light when 24. Inversely, the dial 3 may be transparent or translucent and the opaque appliques 24. It can also be envisaged that the bottom 2, the middle 1 and the dial 3 are opaque and that only a flange disposed between the bezel 26 and the dial 3 is transparent or translucent, thus creating a ring of light all around the ice 34.

In FIG. 5A, there is shown another original embodiment of the invention which aims to inject the light produced by the light source 10 into the strands 30 of a transparent or translucent bracelet. For this purpose, there is provided an opaque middle 1 which has two transparent areas 32a and 32b substantially at noon and six o'clock, that is to say at the places where the strands 30 of the bracelet are attached to said middle part 1. On the side inside the watch case 6, two light sources 10 can each be provided facing one of the two transparent areas 32a, 32b of the middle part 1. The light produced by the two light sources 10 emerges from the watch case 6 by said two transparent areas 32a, 32b and is injected into the two transparent or translucent strands of the bracelet in which it diffuses. According to one variant, the middle part 1 could be transparent or at least translucent. In this case, it will preferably be chosen for the caseband 1 a material whose refractive index is substantially lower than that of the areas 32a, 32b to ensure optimum performance in the injection of light into the strands 30 of the bracelet.

By way of example (see FIG 5B), the light source 10 may be constituted by a light emitting diode whose typical dimensions are of the order of 0.6 mm. However, the section of a strand 30 of the bracelet where this strand is connected to the middle part 1 of the watch is of the order of 20 to 30 mm. To ensure the illumination of the bracelet strand throughout its section, it is possible to give the two transparent zones 32a and 32b through which the light diffuses a cone shape whose aperture at the apex corresponds to the width of the strap strand. . It would also take advantage of the radiation pattern cone of most commercially available light emitting diodes.

According to a particular embodiment of the invention, the transparent portions 32a and 32b may be constituted by two straight sections 68a, 68b of a fiber optic bar (see Fig. 5C). Such sections are better known by their Anglo-Saxon name "Fiber Optical Plate" or "FOP". These sections make it possible to bring back the light produced by the corresponding light source 10 at their respective outlet surfaces 66a, 66b facing the two transparent strands of the bracelet.

An embodiment of a strand 30 of a bracelet is illustrated in FIG. 7. According to this example, the bracelet strand 30 comprises a light guide 48 which preferably extends over the entire length of said strand 30 and in the thickness of which microprisms or microlenses are structured. For optimum performance of the injection of light into the guide 48, the end of said guide 48 located on the side of the middle part 1 of the watch is positioned at the same level as the transparent zone 32a of the caseband 1, opposite the light source 10. The light guide 48 is overmolded in a layer 50 of a transparent plastic material such as silicone or polyurethane. This sandwich structure is completed by a decorative sheet 52 disposed above the light guide 48, that is to say the side of the strand 30 of the bracelet that is not in contact with the wrist of the user. The light injected into the guide 48 is deflected by microprisms or microlenses and illuminates the decorative sheet 52. This decorative sheet 52 is made of a material compatible with silicone or polyurethane such as PMMA. The decorative patterns present in the decorative sheet 52 may for example be obtained by a molding technique known under the name Anglo-Saxon In Mold Decoration or IMD.

Fig. 3 6 attached to the present patent application represents a sectional view along the axis 3:00 to 9:00 of a watch case 6 with digital display. As can be seen from the examination of this figure, the watch case 6 comprises, on the ice side 34, a digital display 36 of the liquid crystal cell type comprising a front substrate 38 extending parallel to and at a distance of a rear substrate 40. The front 38 and rear 40 substrates are joined together by a sealing frame 42 which delimits a sealed volume for the confinement of the liquid crystal. The liquid crystal cell 36 is a so-called backlit cell, that is to say it comprises a light guide 44 for example curved disposed on the side of the rear substrate 40 and which follows the outer contour of said cell. 36. The light produced by a light source 10, typically a light-emitting diode or LED, is injected into the light guide 44 and diffuses therein so as to illuminate the display cell 36 and to allow its reading in darkness. In this case, the originality of the invention lies in the fact that the light that escapes from the sides 46 of the light guide 44 is used to illuminate, for example, the transparent or translucent parts of the middle part 1 of the shows. Thus, in accordance with the invention, the injected light is used in a light guide 44 not only to illuminate a liquid crystal display cell 36 from the rear, but also to illuminate all or part of the trim elements (middle part 1, bezel 26) of a watch case 6.

It goes without saying that various variants and simple modifications can be envisaged by those skilled in the art without departing from the scope of the invention as defined by the appended claims. Thus, as will be understood from the foregoing, the invention relates to a timepiece comprising, in addition to an ice cream, the following trim elements: a bottom 2, a middle part 1, a dial 3, a bezel 26 and two strands 30 of bracelet, at least one of these covering elements being at least partially transparent or translucent, the bottom 2, the middle part 1 and the bezel 26 defining an interior volume 4 of the watch case 6 in which is housed a clockwork movement M, the timepiece being characterized in that it comprises at least one light source 10 housed in the interior volume 4 and producing a light which passes through the transparent part or translucent of the dressing element concerned.

When the covering element concerned is made of a transparent or translucent plastic material, it is tinted in the mass except where or where it is desired that the light escapes from the interior volume 4 of the watch case 6. According to one variant, the covering element concerned made of transparent or translucent plastic material may be covered internally or externally with a layer of light-absorbing material except where or where the it is desired that the light escapes from the interior volume 4 of the watch case 6.

In the case where the light source 10 emits ultraviolet, violet, blue, white or infrared light, the covering element is loaded with fluorescent particles and / or phosphorescent at the place or places where it is desired that the light escapes from the interior volume 4 of the watch case 6.

As will also be understood from the above, the object of the present invention is to make light escape from the interior volume 4 of the watch case 6 to the outside. Another aspect of the invention is to illuminate from the inside 4 of the watch case 6 elements external to it. Thus, the middle part 1 may be transparent or at least translucent at least in its parts 32a, 32b opposite the zones where the strands 30 of the bracelet are connected, so that the light passing through the transparent parts 32a, 32b of the middle part 1 diffuses into the strands 30 of the bracelet which are also transparent or translucent.

According to the other embodiment of the invention, the cladding element is made of a metallic material. In this case, there is provided a through passage in which is engaged a transparent or translucent element where or where it is desired that the light escapes from the interior volume 4 of the watch case 6. As a for example, when the timepiece comprises a winding crown or a pushbutton 16, a transparent or translucent cylinder 20 is engaged in the through passage 18 which can serve both as a mechanical guide for the winding crown or the push button 16 and light guide for the light escaping from the interior volume 4 of the watch case 6, the outer diameter of the transparent or translucent cylinder being greater than the outer diameter of the crown or the pushbutton 16 It should be noted that at least the ignition of the light source 10 can be controlled by the user, for example by pressing a push-button such as the push-button 16 or by applying the command key. gt on a touch key. The extinction of the light source can also be caused by an additional pressure on the push button 16 or be controlled by the control circuit 12 after a predetermined time interval. It can also be provided that the switching on and off of the light source 10 are controlled by an automatic system such as a photosensitive sensor according to the degree of ambient brightness. The photosensitive sensor will control the illumination of the light source when the degree of ambient brightness will fall below a predetermined threshold and will control the extinction of the light source when the degree of ambient brightness exceeds a predetermined threshold. According to another variant, the ignition and extinction of the light source can be controlled by applying a shock on the watch case or by a sudden movement of the wrist, the shock or acceleration being detected by an accelerometer housed in the watch.

According to yet another variant, the light produced by the light source 10 is injected into a diffusing optical fiber 22 which diffuses light over its entire length.

One can also consider making out the light by the dial 3. In this case, the dial 3 is opaque except at the appliques 24 which are transparent or at least translucent and through which the light can escape of the interior volume 4 of the watch case 6. The dial 3 can be made of an opaque material or be transparent and be covered in this case with a layer of an opaque material except at the appliques 24.

Claims (21)

1. Timepiece comprising, in addition to an ice cream, the following trim elements: a base (2), a caseband (1), a dial (3), a telescope (26) and two strands (30) ) of at least one of these cladding elements being at least partially transparent or translucent, the bottom (2), the middle part (1) and the bezel (26) defining an interior volume (4) of the box watch (6) in which is housed a watch movement (M), the timepiece being characterized in that it comprises at least one light source (10) housed in the interior volume (4) of the watch case (6) and producing a light which passes through the transparent or translucent part of the covering element concerned. 2. Timepiece according to claim 1, characterized in that the cladding element concerned is made of a transparent or translucent material chosen from the group formed by plastic materials, ceramic materials, sapphire or fused silica. . 3. Timepiece according to claim 2, characterized in that the covering element concerned is tinted in the mass except where or where it is desired that the light escapes from the interior volume ( 4) of the watch case (6). 4. Timepiece according to claim 2, characterized in that the cladding element concerned is covered internally or externally with a layer of a light-absorbing material except at the place or places where one wish the light escapes from the interior volume (4) of the watch case (6). Timepiece according to one of Claims 1 to 4, characterized in that the light source (10) emits ultraviolet, violet, blue, white or infrared light and that the light element coating is loaded with phosphorescent and / or fluorescent particles where or where it is desired that the light escapes from the interior volume (4) of the watch case (6). 6. Timepiece according to any one of claims 1 to 5, characterized in that the middle part (1) is transparent or at least translucent at least in its parts (32a, 32b) facing the areas where are connected the strands (30) of the bracelet, so that the light passing through the transparent portions (32a, 32b) of the middle part (1) diffuses into the strands (30) of the bracelet which are also transparent or translucent. 7. Timepiece according to claim 6, characterized in that the bracelet strand (30) comprises a light guide (48) in the thickness of which microprisms or microlenses are structured, the light guide (48). being overmoulded in a layer (50) of a transparent plastic material, this sandwich structure being completed by a decorative sheet (52) disposed above the light guide (48), that is to say on the side of the Strand (30) of the bracelet that is not in contact with the wrist of the user. 8. Timepiece according to claim 7, characterized in that the layer (50) in which the light guide (48) is overmolded is made of silicone or polyurethane and that the decorative sheet (52) is made in PMMA, the decorative patterns present in the decorative sheet (52) being obtained by an In Mold Decoration molding technique. 9. Timepiece according to claim 1, characterized in that, when the cladding element is made of a metallic material, there is provided a through passage in which is engaged a transparent or translucent element at the location or where it is desired that the light escapes from the interior volume (4) of the watch case (6). 10. Timepiece according to claim 9, further comprising a winding crown or a push-button, characterized in that the winding crown or the push-button (16) is surrounded by a transparent or translucent cylinder (20). which serves as a light guide for the light that escapes from the interior volume (4) of the watch case (6), the outer diameter of the transparent or translucent cylinder (20) being greater than the diameter of the crown or knob. pusher (16). Timepiece according to Claim 10, characterized in that the cylinder (20) also serves as a mechanical guide for the winding crown or the push-button (16). 12. Timepiece according to any one of claims 1 to 11, characterized in that at least the ignition of the light source (10) is controlled by the user. 13. Timepiece according to any one of claims 1 to 11, characterized in that the ignition of the light source (10) is controlled by an automatic system. Timepiece according to any one of Claims 1 to 13, characterized in that the light produced by the light source (10) is injected into a light guide which then brings the light to the level of the zone or zones. transparent or translucent of the dressing elements considered. 15. Timepiece according to claim 14, characterized in that the light guide is an optical fiber (22) which makes it possible to circumvent any obstacles that may arise between the light source (10) and the transparent or translucent zone. of the considered covering element by which the light will escape from the interior volume (4) of the watch case (6). 16. Timepiece according to claim 15, characterized in that the optical fiber (22) is an optical fiber which diffuses the injected light over its entire length. 17. Timepiece according to any one of claims 1 to 16, characterized in that the dial (3) is opaque except at the appliques (24) which are transparent or at least translucent and through which the light can escape from the interior volume (4) of the watch case (6). 18. Timepiece according to claim 17, characterized in that the dial (3) is made of an opaque material. 19. Timepiece according to claim 17, characterized in that the dial (3) is transparent and is covered with a layer of an opaque material except at the appliques (24). 20. Timepiece according to any one of claims 1 to 16, characterized in that the dial (3) is transparent and in that the appliques (24) are opaque. 21. Timepiece according to any one of claims 1 to 20 comprising, on the side of an ice (34), a digital display (36) under which is disposed a light guide (44) in which is injected the light produced by a light source (10) for backlighting said digital display (36), characterized in that the light that escapes through the light guide (44) sides (46) which are opposite the middle part (1) and the bottom (2) of the watch case (6) passes through the transparent or translucent part of the covering element concerned.