FR2882829A1 - Watch for skin diving, has case enclosing generator converting mechanical energy of rotary mass into energy for operating watch, where inner space of case containing mass is filled with incompressible and viscous liquid e.g. fluorinated oil - Google Patents

Abstract

The watch has a case (1) containing a movement (3), and closed on its reading side by a mirror (4), and on its opposite side by a base. The case encloses a generator which converts mechanical energy, obtained by the rotation or traversing of a rotary mass, into energy that is able to operate the watch. The inner space of the case containing the mass is filled with an incompressible and viscous liquid e.g. fluorinated oil.

Description

The present invention relates to a watch that does not require a source

  external energy, especially electrical or mechanical.

  This watch will be particularly suitable for underwater use at very great depth.

  In the prior art wristwatches are known having devices for generating energy from the oscillations of an oscillating mass mechanically coupled to the generator.

  Such watches have in particular been the subject of patent EP 0 326 312. This document describes a drive device of a generator supplying electrical energy to a capacitor with very high capacity. For this, the device comprises an oscillating mass mechanically coupled to said generator to drive its rotor. There is also provided a friction transmission between the oscillating weight and the rotor of the generator so as to preserve the mechanism of any excessive effort on the teeth of the train in case of shock and thus avoid the breakage of these teeth. In the proposed construction, an intermediate mobile is interposed between the oscillating mass and the rotor. The mass transmits its movement to a pinion of the intermediate mobile, the latter having a friction-adjusted wheel on the shaft of the mobile, this wheel being engaged with a pinion of the rotor of the generator. The friction is calculated so that the wheel slips on the shaft when a shock is applied to the ground or when the torque applied to the rotor exceeds a permissible value. This avoids any breakage of the mechanism.

  It should be noted, however, that in case of mass production, friction of constant value is difficult to ensure and therefore requires adjustments that take time. Moreover, a major flaw of these mechanisms is the noise generated by the oscillating mass during its swinging around the central axis of the watch. On the one hand, in the absence of lubrication, friction often occurs between the mutually interlocking parts causing metal rattling particularly troublesome for the user. On the other hand, the oscillating mass regularly comes into contact with stops disposed on either side thereof and intended to limit its stroke. Depending on the speed of the oscillating weight, this percussion generates a dry sound, relatively violent if it is not slowed beforehand.

  A first object of the invention is therefore to propose a watch with autonomous operation that does not have the disadvantages of the prior art and, in particular, a watch limiting the risk of violent shocks between moving parts under the effect of the mass. oscillating and decreasing the noise generated by the latter during its displacement.

  To this end, the applicant proposes to immerse the entire mechanism intended to provide the energy necessary for the operation of the watch in a liquid having particular physicochemical characteristics enabling it both to ensure good lubrication of the parts. mechanical braking, adapted braking of the oscillating mass and acoustic insulation vis-à-vis the outside. This liquid will also have other qualities to make it compatible with the intended use, in particular electrical insulation properties when the watch has electrical parts 3 and / or electronic.

  The applicant has also had the idea to take advantage of this liquid to adapt a technology previously used in so-called diving watches, that is to say watches capable of undergoing immersions very deep. This technology relies on the use of filling liquid so as to compensate for the strong pressures exerted on the casings of said watches. The incompressible nature of said liquids makes it possible to compensate for the pressure exerted on the external faces of the housings and thus to prevent deformation or even crushing of the latter when they are subjected to these pressures.

  The present invention thus relates to a watch, including diving, consisting of a housing containing a movement, and closed on its reading face by an ice, and on its opposite side by a bottom; said watch being remarkable in that the housing encloses a generator which converts mechanical energy obtained by rotating or moving back and forth a rotary weight into an energy able to operate the watch and in that the internal space of the housing containing the rotating weight is filled with a viscous and incompressible liquid.

  Thus configured, the invention will provide a watch not having the drawbacks mentioned above, in particular, a watch operating autonomously and limiting noise and shock due to the displacement of the oscillating mass. This watch will also be particularly suitable for underwater use in great depth.

  An embodiment of the present invention will be described hereinafter by way of nonlimiting example, with reference to the appended figures, in which: FIG. 1 is a diametrical sectional view of a first variant of FIG. invention.

  Figure 2 is a diametrical sectional view of a second variant of the invention.

  FIGS. 1 and 2 show a watch according to the present invention adapted to go underwater. This watch consists essentially of a metal casing 1, which is circular in top view, and which is hollowed out of a cylindrical internal cavity 2, in which is disposed a movement 3 of analog type. The housing 1 is closed at its upper part by a lens 4 which is fixed at its periphery to the housing 1 by means of sealing means of conventional type.

  According to an essential characteristic of the invention, this movement will include an energy generating device (not shown) from the oscillations of a rotating mass actuated under the effect of the wrist movements of the user. This type of mechanism has in particular been subject to patent protection, in particular in patent EP 0 326 312. In this document, the energy generating device consists of an oscillating weight and a suitable converter means. converting the mechanical energy obtained from the oscillating weight into electrical energy and transmitting it to the movement of the watch.

  The converter means comprises a rotor constituted by a permanent magnet mounted to be driven by the oscillating mass, the rotation of the permanent magnet rotor inducing a voltage in a winding of a transducer connected to the source of electrical energy. It is in particular provided in this document to use torque limiting means so as to temporarily disconnect the rotor from the oscillating mass when the oscillating mass is subjected to a sudden and exaggerated rotational movement. Indeed, excessively high torques can in fact strongly damage the mechanical parts constituting the movement of the watch, in particular for a wristwatch for which the size of the parts does not always make it possible to obtain the desired resistance. In the present invention, these torque limiting means are replaced by a filling liquid having specific physicochemical characteristics. This liquid thus occupies the entire internal space of the watch surrounding the movement provided with the energy generating device. This liquid will in particular have specific physicochemical characteristics to ensure both an absorption of mechanical shocks suffered by the oscillating mass and an attenuation of the noise produced during the movements thereof. This effect may result in particular viscous properties of the liquid. The viscosity of the liquid must be high enough to slow the oscillating mass during violent shocks and low enough to avoid excessive braking of the oscillating weight during normal use of the watch, which would result in insufficient electrical energy to ensure autonomous operation of the watch.

  As such, it will be advisable to choose as a filling liquid a compound of the fluorinated oil type.

  Fluorinated oils indeed ensure good lubrication of moving parts, have a high wettability allowing them to fill all the free internal spaces of the watch and are inert vis-à-vis the other components of the watch.

  This filling liquid will preferably have a viscosity of between 2 and 5 cst (centistokes).

  Moreover, in the specific application of diving watches, this filling liquid will also play the role of incompressible liquid to compensate for the pressure exerted by the external environment on the outer walls of the watch. This liquid should also have the following additional characteristics: low wettability of the housing walls, - lack of toxicity, compatibility with the various watch components and in particular the various seals, - lubrication qualities of the movement when it comprises parts mechanical, - insulation qualities when the movement includes a power supply and / or electrical or electronic parts.

  It has thus been noted that certain liquids were particularly interesting at this level insofar as they possessed both a viscosity and compressibility compatible with the intended uses, as well as one or more of the additional characteristics mentioned above. A fluorinated oil will thus preferably be used.

  In the variant shown in Figure 1, corresponding to an embodiment of a diving watch described in patent FR 2 837 938, the filling liquid 5 completely fills the internal space of the watch delimited respectively by the housing 1 , ice 4 and the bottom of the watch. The latter is made in two elements, namely, a metal ring 6 which is fixed by screwing into a threaded lower cavity 7 of the casing 1, and which carries a circular flat part 8 which, when the ring 6 is fixed on the casing 1, compresses an o-ring seal 9, which is arranged in a circular groove of the casing 1. The second element forming the bottom consists of an elastic circular membrane 10, preferably made of an elastomer or rubber, which comprises a circular rim peripheral 11 of greater thickness, so as to give it a good contact surface, which improves the connection between the membrane 10 and the ring 6. The peripheral flange 11 is housed in a circular bore 12 dug in the lower part of the crown 6 and its peripheral surface bears against the vertical edge of this bore 12.

  In the variant shown in FIG. 2, corresponding to an embodiment of a diving watch described in patent FR 2 752 959, the filling liquid 5 fills an internal space of the watch delimited respectively by the casing 1, the ice 4, a deformable membrane 13 covering a large part of the bottom surface and the portion of the bottom surface not covered by the membrane 13. The bottom 14 thus has an annular flat surface 15 and perpendicular to the axis of the watch, on which is fixed the deformable metal membrane 13 undergoing the pressure of the external medium through perforations 16 provided in the bottom 14. The rigid outer wall of the latter is shaped so as to provide a space 17 for the transverse displacement of the membrane 13 in case of expansion of the liquid under the effect of a rise in temperature.

  Similarly, there is sufficient space between the membrane 13 and the mechanism 3 of the watch allowing the transverse displacement of the membrane to said mechanism in case of decrease in the volume of liquid under the effect of an increase in pressure or a drop in temperature.

  With reference to FIG. 3, there is shown a device making it possible to measure the vibratory and acoustic levels of a watch comprising an oscillating mass according to the invention subjected to reciprocating movements, said movements generally reproducing the movements wrist of a user wearing said watch. This device comprises a vibrating pot oriented at 45 degrees on which is set up a clamping system of the watch case. The inclination at 45 degrees allows, through the rectilinear movements back and forth of the vibrating pot and the effect of gravity on the oscillating mass, the setting in motion of the latter. For the realization of the measurements, the excitation frequency of the vibratory pot was fixed around 9 Hz.

  9 Vibration Level Measurements: A first series of measurements was performed by placing an accelerometer in the center of the face of the watch intended to be in contact with the wrist of the user. This accelerometer makes measurements of the acceleration between 400 Hz and 6 kHz. It thus determines a maximum absolute mean acceleration value and an effective average acceleration value.

  By performing these measurements for an oscillating mass watch immersed in a filling fluid and for a watch similar to the previous one but without filling fluid, it is thus possible to determine the impact of the fluid on oscillations of the oscillating mass.

  The watch used in these experimental tests is substantially identical to that shown in FIG. 2 and, as such, is in accordance with the teachings of patent FR 2 752 959.

  The filling fluid used in the immersed movement watch is, in turn, a fluorinated oil.

  Its viscosity is in particular of 2.4 cst (centistokes) at 25 C.

  All measurements made at this level have been reproduced in Table 1.

TABLE 1

  Motion Movement Relative dry relative difference in% Absolute value 4.23 m / s2 2.24 m / s2 47.1% maximum Value 0.624 m / s2 0.268 m / s2 57.0% effective The vibratory level of the watch with immersed movement is thus below that of a similar watch with non-immersed movement, and preferably at least less than half that of a similar watch with non-immersed movement.

  Acoustic Level Measurements: A second series of measurements was performed by placing a sound level meter about 10 cm from the watch, the sound level meter being directed towards the face of the watch intended to be in contact with the wrist of the user.

  The sound level meter thus determines the average sound pressure level generated by the watch during the reciprocating movements of the oscillating pot.

  These measurements were made for the same watch as previously with an oscillating mass immersed in the same filling fluid as before and for a watch similar to the previous but without filling fluid.

  All measurements made at this level are shown in Table 2.

TABLE 2

  Motion Movement Difference in immersed dry dB Level 50.3 dB 36.7 dB 13.6 dB average acoustics In view of the results, there is a clear decrease in the noise level in the case of the underwater oscillating weight watch compared to the same oscillating weight watch evolving in a dry environment, in particular a decrease greater than 10 dB.

  It can thus be seen that by using a suitable filling fluid, it is possible to obtain a watch having the ability to evolve under water at very great depth, while being relatively silent at the surface, given the presence an oscillating mass within its drive mechanism.

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Claims (8)

  1 - Watch, including diving, consisting of a housing (1) containing a movement (3), and closed on its reading face by an ice (4), and on its opposite side by a bottom, characterized in that the housing (1) contains a generator which converts mechanical energy obtained by rotating or moving back and forth a rotating mass into energy able to operate the watch and in that the internal space of the housing (1) containing the rotating mass is filled with a viscous and incompressible liquid (5).   2 - Watch according to the preceding claim, characterized in that the filling liquid (5) has a viscosity of between 2 and 5 cst (centistokes).   3 - Watch according to one of claims 1 or 2, characterized in that the filling liquid (5) is a compound of the fluorinated oil type.   4 - Watch according to any one of the preceding claims, characterized in that the filling liquid (5) is able to induce a vibratory level in the watch lower than that of a similar watch without filling fluid, and preferably , less than half that of a similar watch without filling fluid.   - Watch according to any one of the preceding claims, characterized in that the filling liquid (5) is able to induce a noise level in the watch lower than that of a similar watch without filling fluid, and preferably , -13 - dB lower than that of a similar watch without filling fluid.   6 - Watch according to any one of the preceding claims, characterized in that the inner space of the housing (1) containing the rotating mass is defined by at least one deformable membrane (13).   7 - Watch according to the preceding claim, characterized in that the deformable membrane (13) defines the bottom of the watch.   8 - Watch according to claim 6, characterized in that the deformable membrane (13) defines with the bottom of the watch a space not filled with liquid, said space allowing the transverse displacement of the membrane (13) in case of expansion of the liquid (5).   9 - Watch according to the preceding claim, characterized in that the bottom is provided with perforations (16).