ISOTHERMAL DEVICE FOR A CLOCK

Description

Technical field of the invention

[0001] The invention relates to an isothermal device for mechanical and / or functional components of a watch arranged in a case of this device, said device comprising a dynamic temperature control system for the enclosure of this case. Technological background

[0002] A watch typically consists of a strap and a watch case containing several mechanical and / or electronic components. It is known that some of these components cannot withstand certain temperatures and cease to function correctly at those temperatures.

[0003] Therefore, there is a need to be able to use a watch, particularly an electronic watch, in environments where such temperatures may prevail. Document EP 4 012 512 A1 discloses an isothermal device according to the preamble of claim 1. Summary of the invention

[0004] To this end, the invention relates to an isothermal device for mechanical and / or functional components of a watch, comprising a case provided with an enclosure in which a watch case can be removably arranged, the case having a crystal arranged opposite a crystal of said case, said device comprising: a reversible fixing device fixing said watch case in said enclosure keeping it away from functional elements of said case, said elements forming this enclosure comprising a case middle, a base and the variable opacity crystal of this case, and a dynamic temperature control system for this enclosure comprising said variable opacity crystal and a control unit configured to control the opacity of said crystal of the case.

[0005] In other embodiments: said variable opacity glass includes a transmittance variation element of said glass; the control unit (8) is connected via a linking element to the transmittance variation element of the variable opacity glass; the variable opacity glass includes a transparent substrate, a lower surface of which includes a transmittance variation element; the variable opacity glass includes a transparent substrate including a transmittance variation element contained within its body; the transparent substrate is formed of two layers of transparent material between which the transmittance variation element, consisting of a stack of functional layers, is arranged; the control unit includes at least one event sensor, said event being capable of causing a temperature variation within the enclosure, such a sensor being a light sensor and / or a temperature sensor;The element that varies the transmittance of the variable opacity glass is an electrochromic element, in particular a liquid crystal electrochromic element; said enclosure is under vacuum or near-vacuum; the variable opacity glass has a surface area that is substantially larger or strictly larger than that of the watch case glass. Brief description of the figures

[0006] Other features and advantages will become clear from the description given below, which is indicative and in no way exhaustive, with reference to the attached figures, in which: there figure 1 is a schematic representation of a top view of an isothermal device comprising a housing equipped with a glass pane including an element for varying the transmittance of said glass pane, according to embodiments of the invention, and the figure 2 is a cross-sectional view along axis II-II of the schematic representation of the watch of the figure 1 , according to the embodiments of the invention. Detailed description of the invention

[0007] THE figures 1 and 2 represent an isothermal watchmaking device 1 for mechanical and / or functional components 5 of a watch 10. This isothermal device 1, also called "Dewar clockwork device" or more simply " Dewar's device includes a thermal protection box 2. Such a box 2 is also called insulated case or even Dewar case » .This isothermal device 1 for thermal protection of mechanical and / or functional components 5 of a watch 10 is suitable for providing good thermal insulation to the mechanical and / or functional components 5 of the watch 10, a case 12 of which must be arranged within an enclosure 4 of this case 2 in order to ensure such thermal insulation for these components 5. In other words, this enclosure 2 is formed in particular by the combination of its functional elements 15 with the case 12 of the watch 10 in order to achieve suitable thermal insulation for these mechanical and / or functional components 5. These functional elements 15 of the case 2, forming this enclosure 4, include a crystal 6, an inner peripheral wall 17 of a case 9a, and a case back 9b of this case 2. In this configuration, the case 12 of the watch 10 is arranged within such an enclosure 4, being kept away from or at a distance from the functional elements of the case 2. forming this said enclosure 4.It should be noted that this inner peripheral wall 17 of the frame 9a is also that of the said enclosure 4.

[0008] In this isothermal device 1, the housing 2 includes a dynamic temperature control system 3 for its enclosure 4. Such a system 3 helps to regulate the temperature within this enclosure 4. To do this, this system 3 includes the glass 6 of the housing 2, which is a transparent glass 6 with variable opacity, also more simply called a glass 6 with variable opacity, and a control unit 8 connected to this glass 6 which is configured to control / manage this opacity.

[0009] In this context, the control unit 8 comprises an electronic circuit including a controller equipped with hardware resources, in particular at least one processor cooperating with memory elements, as well as data and control address buses, and also an energy storage device, also known as a battery. This control unit 8 includes in its memory elements a temperature management algorithm for enclosure 4 of the housing 2. This algorithm is executed by the processor of this control unit 8, taking into account, in particular, data from event sensors included in the control unit 8, in order to ensure temperature management in enclosure 4 of the housing 2. It should be noted that such data may, for example, provide information relating to events detected by these sensors, said events being likely to contribute to, cause, or generate a variation in the temperature in enclosure 4 of the housing 2.These events may include, but are not limited to: the detection of a particular level of brightness in the environment of the isothermal device 1, in particular solar radiation, and the detection of a temperature variation in the enclosure 4 relative to a configurable reference temperature, etc.

[0010] In this context, the event sensor includes, in particular and without limitation: a light sensor comprising a solar radiation sensor and / or an infrared solar radiation sensor and / or an ultraviolet solar radiation sensor, and / or a temperature sensor.

[0011] It should be noted that each event sensor is part of the control unit 8 and is connected to the controller of this unit 8. The temperature sensor is arranged in the enclosure 4 of the housing 2. As for the light sensor, it is located in the housing 2 and in particular in at least one of the functional elements 15 of this housing 2 so as to be exposed to light coming from the external environment of the isothermal device 1 and therefore of the housing 2. By way of example, this light sensor can be arranged in the body of the glass 6 of the housing 2 and / or on an internal face 16 of this glass 6.

[0012] In this isothermal device 1, the control unit 8 comprises a substrate such as a flexible PCB on which its electronic circuit is mounted, with the exception of the light sensor, which may be contained within the glass 6 or on an inner face 16 of this glass 6 of the housing 2. In this context, the construction of this circuit on this substrate can be carried out using 3D printing processes or polymer printing processes. It should be noted that this substrate is mounted in the enclosure 4 on one of the functional elements 15, such as the inner face 18 of the base 9b or on the inner peripheral wall 17 of the enclosure 4.

[0013] As mentioned earlier, the control unit 8, and in particular its controller, is connected via a linking element 14 to the lens 6 of the housing 2. This lens 6 consists of a substrate and a transmittance variation element 7 for this substrate, and by extension, for the lens 6 itself. Such a transmittance variation element 7 is, for example, an electrochromic element, specifically a liquid crystal electrochromic element. Recall that this transmittance is the amount of energy (thermal or light radiation) that the lens 6 of the housing 2 is capable of transmitting relative to the flux of incident solar radiation. It should be noted that such a substrate is made of a material such as glass, including mineral glass, optical ceramic, acrylic glass, or sapphire glass.

[0014] Such a transmittance variation element 7, when it is an electrochromic element, comprises a layer of an electrochromic material capable of reversibly and simultaneously inserting cations and electrons, and whose oxidation states corresponding to the inserted and uninserted states are distinctly colored, one of the states exhibiting higher light transmission than the other. The insertion or uninsertion reaction is controlled by the application of an electrical voltage by the control unit 8. The electrochromic material, usually tungsten oxide-based, must therefore be brought into contact with an electron source such as a transparent electroconductive layer and a cation source such as an ionically conductive electrolyte.

[0015] In a first variant of the glass 6 of the housing 2, the transmittance variation element 7 is arranged / applied / printed / deposited on a lower surface of the substrate, thus forming the inner face 16 of this glass 6. This transmittance variation element 7 is formed, in a manner known per se, from a stack of functional layers. More precisely, when it is an electrochromic liquid crystal element, it comprises a film placed between first and second electroconductive layers and based on a polymeric material in which liquid crystal droplets are dispersed, notably nematic droplets with positive dielectric anisotropy. When the film is energized, the liquid crystals align themselves along a preferred axis, configuring the glass 6 in a first state where the transmittance of this glass 6 is at its maximum.When the film is switched off, in the absence of crystal alignment, the film becomes diffusive and absorbing, and the ice 6 is then configured in a second state where its transmittance is minimal or even zero.

[0016] In a second variant of the lens 6 of the housing 2, the transmittance variation element 7 is contained within the body of the substrate forming this lens 6 of the housing 2. In this context, this substrate can then be formed of two layers of transparent material such as glass, between which layers is arranged the transmittance variation element 7, consisting of a stack of functional layers. When this transmittance variation element 7 is an electrochromic element, these functional layers may include, for example: a first electroconductive layer; a first layer of anodic electrochromic material in hydrated iridium oxide, (it could be replaced by a layer in hydrated nickel oxide); a layer in hydrated tantalum oxide with a protective function; a layer of electrolyte in solid solution of polyoxyethylene with phosphoric acid; a second layer of cathodic electrochromic material based on tungsten oxide; a second electroconductive layer.

[0017] It should be noted that in both variants, the stack of functional layers forming the transmittance variation element 7 may include an additional layer of thermoplastic polymer such as polyvinyl butyral, known by the acronym PVB, which preferably contains ultraviolet filtering agents. Such a layer may be arranged in the first variant immediately after the first electrically conductive layer, and in the second variant between the glass layer and the first electrically conductive layer.

[0018] Thus, the control unit 8, by controlling / managing the variation of an electrical voltage applied to the first and second electroconductive layers of the transmittance variation element 7, allows the transmittance property of the glass 6 of the housing 2 to be varied between the first and second transmittance states. Recall that the first state here relates to a maximum transmittance of this glass 6, in which state the glass 6 of the housing 2 is transparent, thus allowing solar radiation to penetrate the enclosure 4 of the latter. The second state relates to a minimum or even zero transmittance of the glass 6, in which state the glass 6 is wholly or partially opaque, preventing / blocking the penetration of solar radiation, at least 99 percent, into this enclosure 4. In other words, in this second state, solar radiation is no longer transmitted by the glass 6 into the enclosure 4 of the housing 2.

[0019] Furthermore, as previously mentioned, the watch case 12 is arranged within the housing 2 of this isothermal device 1, being kept at a distance 19 from the inner peripheral wall 17 of the enclosure 4, thanks to the reversible fastening device 13 of the housing 2. In other words, such a fastening device 13 is capable of creating a gap 19 between said case 12 and functional elements of the housing 2 forming said enclosure 4. In this configuration, the fastening device 13 helps to reduce or even eliminate any thermal conduction between the inner peripheral wall 17 of the case 9a (or the enclosure 4) and / or the case back 9b and / or the crystal 6 and the watch case 12, in particular with an overall external face of this case 12.This overall external face comprises an upper face including the glass 11 of the case 12 of this watch 10, an lower face including a bottom of said case 12 and an external peripheral wall of a case of this case 12.

[0020] In this configuration, the fastening device 13, which provides a reversible fastening of the watch case 12 10 onto the inner peripheral wall 17 of the enclosure 4 of this case 2, may include: connecting elements, each having first and second ends capable of connecting respectively to the watch case 12 10 and to the inner peripheral wall 17 of the enclosure 4 of this case 2. The body of each element has a particular structure which contributes to ensuring a reduction of heat losses to the external environment of the case 2 of the isothermal device 1 and thus to ensuring a stable internal temperature in the watch case 12 10, and / or connecting elements configured to ensure magnetic levitation of said watch case 12 10 in said enclosure 4. Indeed, these connecting elements are configured to ensure and maintain a spacing 19 between said case 12 and the functional elements 15 forming said enclosure 4 of the case 2.Such connecting elements help to reduce or even eliminate any thermal conduction between the inner peripheral wall 17 of the case 9a and / or the back 9b and / or the crystal 11 with the watch case 12 10 in particular with an overall external face of this case 12. .

[0021] Note that box 12 is included in a watch 10 which can be an electronic watch for example a quartz watch, or a mechanical watch or an electromechanical watch.

[0022] The mechanical and / or functional components 5 of the watch 10, mentioned previously, include, but are not limited to: a watch movement, a display device such as a dial, hands, rings, gaskets, and / or electronic and / or electrical components. It should be noted in particular that such electronic and / or electrical components include, for example, a display device, a processor, memory, an energy storage component, a motor, an integrated circuit, and an electronic oscillator, etc.

[0023] In this context, this device 1 therefore includes the case 2, which has the case middle 9a on which a strap 9c is mounted, allowing a user of this device 1 to wear it. This case 2 also includes the crystal 6 and the case back 9b mentioned earlier. In this device 1, it should be noted that the crystal 6 preferably has a surface area that is substantially larger or strictly larger than a crystal 11 of the watch case 12 10. In other words, the inner face 16 of the crystal 6 has a surface area that is substantially larger or strictly greater than or equal to that of an upper face of the crystal 11 of the watch 10.

[0024] As we have seen, the functional elements 15 such as the crystal 6, the case 9a and the case back 9b of this device 1 together define the enclosure 4 of this case 2 which is capable of receiving the watch case 12 10. These three elements 15 of the case 2, namely the case 9a, the crystal 6 and the case back 9b, can be distinct elements which are joined together to construct this enclosure 4. Alternatively, the case 9a and the case back 9b of the case 2 can together form a single piece, said single piece defining an opening opposite the case back 9b which is capable of being closed by the crystal 6 in a reversible and watertight manner. Alternatively, the case 9a and the crystal 6 of the watch case 2 10 can together form a single piece, said single piece defining an opening opposite the crystal 6 which is capable of being closed by the bottom 9b and this also in a reversible and waterproof and airtight manner.

[0025] The case 9a and the base 9b are preferably made, without limitation or exhaustiveness, of a metallic material, glass, or thermosetting or thermoplastic polymer resins reinforced with carbon or glass fibers, or even ceramic materials. It should be noted that when the case 9a and the base 9b are transparent or semi-transparent, for example, by being made of glass, the inner peripheral wall 17 of the case 9a and the inner face 18 of the base 9b may be coated with a metallic or similar reflective coating, such as, for example, a layer of silver.

[0026] Furthermore, in this arrangement, when the watch case 12 is placed within the compartment 4 of the case 2, the space defined between this case 12 and the inner peripheral wall 17 of the case 9a, the case back 9b, and the crystal 6 is empty or nearly empty. In other words, the compartment 4 is under vacuum or nearly under vacuum.

[0027] It is therefore clear that in this configuration, this isothermal device 1 exhibits the same properties and characteristics as a Dewar flask, a well-known example in the prior art. As previously mentioned, the properties and characteristics of this isothermal device 1 contribute to its good thermal insulation against extreme temperatures that may prevail in the external environment where such a device 1 may be located.

[0028] In addition, it should be noted that the mechanical and / or functional components 5 of the watch 10 may be non-magnetic and / or that the case 2 of the watch 10 may be made of a material or be covered with a coating that allows these components to be isolated from magnetic fields.

[0029] In addition, the fastening device 13 helps to position the watch case 12 of the watch 10 in this case 2 so that the glass 11 of this watch case 12 of the watch 10 is arranged opposite the glass 6 of the case 2 so that the information included on the dial and / or the display interface of this watch 10 can be perceived through the transparent glass 6 of the case 2 by the user wearing the isothermal device 1.

[0030] Thus, such an isothermal device 1 provides the mechanical and / or functional components 5 of the watch 10 with excellent thermal insulation from the external environment by reducing or even preventing heat loss by radiation from the components housed in the watch case 12 over a prolonged period. Therefore, when the temperature outside the device 1 reaches extreme values, the temperature inside the enclosure 4 remains approximately equal to the temperature inside the watch case 12 when it was placed in the housing 2, typically around 20°C. It should be noted that regardless of the temperature conditions surrounding the isothermal device 1, the temperature inside the watch case 12 does not impede the proper functioning of the watch 10.This temperature is maintained for a period that is 2 to 18 times longer than the period during which such a watch case 12 would be able to maintain an operating temperature of its components by being located directly in such an environment where such temperatures prevail, i.e. by being located outside the case 2 of the isothermal device 1. It is thus understood that such a configuration makes it possible to protect the mechanical and / or functional components 5 of the watch 10, as well as to help ensure their optimal operation in extreme external temperature conditions.

[0031] It is understood that the present invention is not limited to the embodiments just described and that various simple modifications and variations can be envisaged by a person skilled in the art without departing from the scope of the invention as defined by the appended claims. For example, the control unit 8 could include a motion sensor for the isothermal device 1, enabling, in particular, the transition of the glass 6 of the case 2 from the second state to the first transmittance state, as soon as it is detected that the user of the isothermal device wishes to view information displayed on the dial of the watch 10 by orienting the glass 6 of the case 2 towards their gaze. Such a sensor could be a gyroscopic and / or inertial sensor in the form of a gyroscopic and / or inertial microelectromechanical circuit.

Claims

1. Isothermal device (1) for mechanical and / or functional components (5) of a watch (10), comprising a case (2) provided with an enclosure (4) wherein a case (12) of said watch (10) can be removably arranged, a crystal (11) of which is arranged facing a crystal (6) of said case (2), said device (1) comprising : - a reversible fastening device (13) fastening said watch (10) case (12) in said enclosure (4) by keeping it away from functional elements (15) of this case (2), said elements (15) forming this enclosure (4) comprising a middle (9a), a back (9b) and the variable-opacity crystal (6) of this case (2), characterised in that said device (1) comprises: - a system (3) for dynamically controlling the temperature of this enclosure (4) comprising said variable-opacity crystal (6) and a control unit (8) configured to control the opacity of said crystal (6) of the case (2).

2. Device (1) according to the preceding claim, characterised in that said variable-opacity crystal (6) comprises an element for varying its transmittance (7).

3. Device (1) according to the preceding claim, characterised in that the control unit (8) is connected using a connecting element (14) to the element (7) for varying the transmittance of the variable-opacity crystal (6).

4. Device (1) according to any one of the preceding claims, characterised in that the variable-opacity crystal (6) comprises a transparent substrate, a lower surface of which comprises an element for varying the transmittance (7) of said crystal (6).

5. Device (1) according to any one of claims 1 to 3, characterised in that the variable-opacity crystal (6) comprises a transparent substrate including a transmittance variation element (7) comprised in its body.

6. Device (1) according to the preceding claim, characterised in that the transparent substrate is formed by two layers of transparent material between which layers the transmittance variation element (7) formed by the stack of functional layers is disposed.

7. Device (1) according to any one of the preceding claims, characterised in that the control unit (8) comprises at least one event sensor, said event being capable of causing a temperature variation in the enclosure (4) of the case (2), such a sensor being a luminosity sensor and / or a temperature sensor.

8. Device (1) according to any one of claims 2 to 7, characterized in that the element for varying the transmittance (7) of the variable-opacity crystal (6) is an electrochromic element, in particular a liquid-crystal electrochromic element.

9. Device (1) according to any one of the preceding claims, characterised in that said enclosure (4) is in a vacuum or quasi-vacuum.

10. Device (1) according to any one of the preceding claims, characterised in that the variable-opacity crystal (6) has a surface area which is substantially greater than or strictly greater than that of the crystal (11) of the watch (10) case (12).