Abstract:
A mechanical-type watch movement is disclosed. In one implementation, the movement may include a frame. The frame may support a work train that is periodically driven in rotation by a driving element. The frame may also support an animation part. The animation part may be configured to be visible, and may be arranged to be animated by an oscillating movement that is capable of simulating, for example, a pendulum movement. The movement may also include, supported by the frame, an animation train that meshes with a mobile of the work train, and is kinematically connected to the animation part.

Description:
This application is a national stage filing under 35 U.S.C. § 371 of International Application No. PCT/CH2004/000542, filed on Aug. 27, 2004, which claims priority to European Application No. 03405624.2, filed on Aug. 29, 2003, the disclosures of which are expressly incorporated herein by reference to their entireties. 
     TECHNICAL FIELD 
     The present invention relates to watch movements and more particularly, to watch movements including a visible mobile element ensuring an animation of a display. 
     Embodiments of the present invention include a mechanical-type watch movement, comprising a frame and, supported by the frame:
         a work train comprising a plurality of mobiles periodically driven in rotation by a driving element,   a mobile animated by a pulsed movement and including a kinematic connection with the work train,   an animation part configured to be visible and arranged to be animated by a periodic movement,   a control element for the animation part, and   an animation train in mesh with a mobile of the work train and driving the control element.       

     BACKGROUND INFORMATION 
     A watch movement is described, for example, in patent CH 30.220, which proposes to animate a figurine by means of a wheel connected to a work train comprising ratchet teeth. The latter periodically drives a rod forming part of an automaton. Such a solution has the drawback that the movement of the automaton is jerky, owing to jumps over the ratchet teeth. 
     Furthermore, watches are known such as that described in document FR 630.190, in which a pendulum image is fixed on a pallet fork of an escapement. This image is thereby abruptly displaced with each alternation. Here, too, the movement is jerky and therefore more irritating than calming. 
     SUMMARY OF THE INVENTION 
     An object of an exemplary embodiment of the present invention is to realize an animation in which the jerks due to the pulsed movement of an escapement or of a motor are gradually dampened in order that the movement of an automaton is uniform and jerk-free. To this end, a watch movement according to one aspect of the invention may include an animation train, a control element and an animation part, arranged in such a way that movement of the automaton has a sinusoidal oscillation movement. 
     In order to obtain an optimal simulation quality, an elastic element may be interposed between a mobile of a work train with which the animation train is in mesh and the animation part, thus forming a mechanical filter through the combination of the elastic element with the inertia of the mobiles of the animation train, the control element and the animation part. 
     From the point of view of the arrangement of the various components, it may be advantageous for the animation train to be connected to the work train by a seconds mobile. In such an embodiment, the animation train may be arranged to accelerate the rotation speed of the seconds mobile toward the mobile cooperating with the animation part. 
     Advantageously, the animation part may oscillate at a frequency ranging between 0.2 and 2 Hz. 
     In one particular embodiment, the movement may also include a lever. A last mobile of the animation train may be equipped with a board. Moreover, the animation part and the board may be equipped with eccentrically disposed connecting means arranged to be connected to one of the ends of the lever, in order to form a connecting rod connecting the animation train to the animation part. 
     In a first variant, the lever may include, over at least a part of its length, an elastically deformable structure, arranged in such a way as to constitute the elastic element. 
     In a second variant, the elastic element may elastically connect two coaxial mobiles of the animation train. 
     Advantageously, the elastic element may form, with the animation part and the mobile(s) of the train interposed between that which may cooperate with the animation part and that which may be connected to the elastic element, an oscillating system, having a period ranging between that the mobiles of the work train and that of the periodic movement of the animation part. 
     In order to make the animation part as shockproof as possible, it may be mounted pivotably on the frame, and its center of gravity may be located substantially on its pivot axis. 
     In order to allow the use of an already existing watch caliber, the frame of the movement according to an embodiment of the invention may include:
         a first plate and a first bridge, between which pivot the mobiles of the work train, and   a second plate on which pivot the mobiles of the animation train and the animation part, the second plate, the animation train and the animation part together forming an independent module which can be fixed by the second plate onto the first plate.       

     It is clear that all or part of the animation train can likewise pivot within a bridge, which may be fixed on the second plate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages and characteristics of the invention will emerge from the following description, made with regard to the appended drawings, in which:
           FIG. 1  represents a watch equipped with a watch movement according to one exemplary embodiment of the invention.     FIG. 2  is a plan view of a part of the watch movement according to one exemplary embodiment of the invention.     FIG. 3  is a sectional view along the lines III-III of the movement part illustrated in  FIG. 2 .     FIGS. 4 and 5  show, on a larger scale and respectively in plan view and in section, a part of the movement of  FIGS. 2 and 3 .     FIG. 6  is a sectional view of a watch movement according to a second exemplary embodiment of the invention.     FIG. 7  represents a third exemplary embodiment of the invention.       

     
    
    
     DETAILED DESCRIPTION 
     The watch represented in  FIG. 1  comprises a case  10  defining a receptacle in which there may be disposed a watch movement which will be described with reference to, for example,  FIGS. 2 to 5 . The movement may include a work train and a minute train bearing, respectively, second hands  12 , minute hands  14  and hour hands  16 . A dial  18  may be interposed between the movement and the hands. Dial  18  may be pierced by a window  20 , through which can be seen an animation part  22 , arranged in such a way as to simulate the movement of a pendulum, as will be explained below. 
       FIG. 2  shows, in top view, a watch movement  24  according to one exemplary embodiment of the invention. Watch movement  24  is housed in case  10 . In  FIG. 2 , dial  18  has been removed, and hands  12 ,  14  and  16  are visible in transparency. Animation part  22  can likewise be seen, with its extreme positions shown in dotted representation. 
     Movement  24  may include a base caliber  26 , represented schematically in side view in  FIG. 3 , ensuring the vital functions of a timepiece, i.e. the power supply, the generation of a base frequency, the mechanical division by means of trains, as well as the correction functions. The time base of movement  24  may include a quartz, a hairspring, and/or any other suitable time base known in the art. 
     Caliber  26  may be equipped with a plate and a bridge (neither of which is referenced), and with a work train that includes mobiles that may be pivotably mounted between the plate and the bridge. Only the end of a seconds mobile  30  is visible in  FIG. 3 . A minute train, which is also not shown in  FIG. 3 , may bear and carry out the driving of minute hands  14  and hour hands  16 . 
     Base caliber  26  may bear a module  32  that includes a plate  34  and a bridge  36  which, together, may serve as support for an animation train  38 . The latter may include three mobiles  40 ,  42  and  44 , each formed by a pinion identified by the letter “a”, and by a wheel identified by the letter “b”, with the exception of mobile  44 , which may include a pinion  44   a  and a board  44   c , but no wheel. 
     Mobile  40  may be coaxial to seconds wheel  30 . Pinion  40   a  may be equipped with a hole engaged in the end of seconds mobile  30 , the hole and the end being arranged in such a way that mobiles  30  and  40  may rotate as one, owing, for example, to an indentation arranged on pinion  40   a . In such an embodiment mobile  40  may be press-fitted on the end of mobile  30 . 
     The wheel  40   b  may drive pinion  42   a  and, with it, wheel  42   b , which may mesh with pinion  44   a  of the mobile  44 . 
     Mobiles  40 ,  42  and  44  may be numbered in such a way that the speed of rotation of mobile  44  may be of the order of 1 revolution per second, typically ranging between 0.2 and 2 revolutions per second. 
     Mobiles  40  and  42 , as well as pinion  44   a , may be disposed between and may pivot between plate  34  and bridge  36 . As can be seen in  FIG. 5 , pinion  44   a  is may be equipped with a pivot  44   d  projecting from bridge  36  and on which board  44   c  may be press-fitted. The latter may support a rod  44   e , the function of which will be specified further below. 
     Animation part  22  may include a central portion  22   a  ( FIG. 2 ) equipped with a hole in which a shaft  22   b , pivotably mounted between the plate  34  and the bridge  36 , proximate to the center of the movement, may be press-fitted. Two arms  22   c  and  22   d  may extend on either side of central portion  22   a . The free end of arm  22   c  may include a bob  22   d , which may be apparent through window  20 , and may simulate the bob of a pendulum. The end of arm  22   d  may be equipped with a rod  22   e , which can better be seen in  FIG. 5  and may be intended to secure a connection with the board  44   c , via a lever  46  pivotably mounted on rods  44   e  and  22   e . Thus, mobile  44  and lever  46  together may form a control element for animation part  22 . 
     Lever  46  may include two watchmaker&#39;s jewels  46   a  and  46   b , press-fitted respectively at one and the other of its ends. One of the jewels  46   a  and  46   b  may cooperate with rod  22   e , and the other may cooperate with rod  44   e . In its middle part  46   c , lever  46  may include a serpentine structure, which may give it greater elasticity than a straight bar. 
     Lever  46  may be held on rods  22   e  and  44   e  by sleeves  48  press-fitted on rods  22   e  and  44   e , leaving a sufficient space with jewels  46   a  and  46   b  to ensure that these are not impeded in their movement. 
     Mobile  44  and lever  46  thus together may form a connecting rod system driving animation part  22 . 
     In the watch which has just been described, when it is of the hairspring type, the seconds wheel may perform a slight jump each time that an escapement gives an impetus to a balance wheel. This may occur with each semioscillation, i.e. from 5 to 10 times per second. This frequency may be too low to simulate a continuous movement. In practice, the duration of the impetus may be of the order of 1% of the time of the half-period. For the pendulum to give the illusion of having a continuous and sinusoidal movement, it may be necessary to introduce an element that may dampen the movement, such as, for example, serpentine structure  46   c , which may lend a greater elasticity to lever  46 . 
     Additionally or alternatively, elastic structure  46   c  of lever  46  could be replaced by mounting wheel  42   b  in a freely rotatable manner on pinion  42   a , and by connecting them with a flat spiral spring (not shown). 
     In order to obtain an optimal simulation, the period of the unit formed by animation part  22  and elastic element  46   b  may range between that defined by the periodicity of the advancement of the work train and that of the oscillating movement of animation part  22 . 
     In order to ensure that the oscillation movement of animation part  22  suffers the least possible perturbations, the unit formed by lever  46  and animation part  22  may be balanced, wherein its center of gravity may be located substantially on the pivot axis of animation part  22 . 
     Additional or alternative ways of ensuring the connection of animation part  22  with animation train  38  may be realized by other means than those represented and described. It may thus be possible to realize an animation part whose arm  22   d  may be considerably shortened and may bear a pin. Lever  46  may be replaced by a fine spring, fixed on the pin of lever  22   d . The other end of the spring may be equipped with a protuberance in which a jewel similar to jewel  46   b  may be press-fitted. It may thereby be possible to have a more flexible elastic element. 
     Additionally or alternatively, animation part  22  could equally have a form other than that of a pendulum, with its verge and its bob, without departing from the scope of the invention. For example, animation part  22  could have the form of a boat, with an oscillating movement simulating the movement of waves, or of any other object performing a slow pendulum movement. 
     It is also contemplated that the components ensuring the drive of the animation part may be integrated directly onto the plate of the base caliber. 
     The exemplary embodiment shown in  FIG. 6  may allow the smoothness of the movement of the automaton to be further improved. In  FIG. 6 , only the mobiles have been represented. The mobiles may pivot within the frame of the movement, generally between a bridge and the plate. In this exemplary embodiment, the driving element, which supplies the power to the work train, may be formed by a barrel spring, housed in a barrel  50 , constituting the first mobile of the work train, the latter driving an escapement and a hairspring, which together may form a pulsed movement element. The animation train may include five mobiles  52 ,  54 ,  56 ,  58  and  60 . 
     Mobile  52  may include a pinion  52   a , in mesh with the toothing of barrel  50 , and a wheel  52   b , which drives mobile  54  via a pinion  54   a . The latter may be attached to a collet  54   b , fixed by press-fitting and bearing a balance spring  54   c . A wheel  54   d  may be mounted relatively loosely on pinion  54   a , held axially in place by a ring  54   e  press-fitted on the shaft of pinion  54   a . Wheel  54   d  may be equipped with a stud  54   f  fixed to the end of balance spring  54   c . Balance spring  54   c  may be fixed on collet  54   b  and on stud  54   f  in traditional manner, for example by gluing or welding. Pinion  54   a  and wheel  54   d  may thereby rotate as one, but may be elastically connected one to the other, dampening the jerks due to the jerky movements of the balance wheel. It is may also be possible to arrange balance spring  54   c  and its fixing means, i.e. collet  54   b  and stud  54   f , in a single piece, press-fitted on pinion  54   a  and on a stud contained on wheel  54   d.    
     Wheel  54   d  may mesh with mobile  56  and, more particularly, with pinion  56   a , whereas wheel  56   b  may drive mobile  58  via pinion  58   a . Wheel  58   b  may mesh with pinion  60   a  of mobile  60 . The latter may include a board  60   b  bearing a rod  60   c , similar to rod  44   e , and on which lever  46  may pivot. 
     Board  60   b  may be dimensioned such that it may form a sufficient mass of inertia to enable balance spring  54   c  to remain slightly wound, such that the pendulum may continue moving between two alternations of the balance wheel. The dimensioning of the balance spring and of the mass of inertia may be delicate since the power may be tapped from a rapid mobile of the gear work train. 
     Additionally or alternatively, the tapping may be effected from the center wheel or from the third wheel. Nevertheless, by tapping the power at the level of the barrel, the number of mobiles contained between the element animated by a pulsed movement, i.e. the escapement, and the element simulating a sinusoidal movement, i.e. the pendulum, is such that their elasticity may be sufficient to make the impetuses of the balance wheel invisible. Therefore, it may not be essential to add a supplementary elastic element, even if the animation part oscillates at a relatively high frequency, such as, for example, 2 Hz. 
       FIG. 7  shows another exemplary embodiment of the invention, in which the animation train  38  may be confined to a wheel  62  disposed on the shaft of the seconds wheel of the work train and the last mobile  44 , whose pinion  44   a  may mesh with wheel  62 . As explained above, board  44   c  may drive animation part  22 . 
     The gearing ratio between wheel  62  and pinion  44   a  may be 1/12, such that the period of the animation part may be 5 seconds. In this case, the pulsed movement of the work train may be heavily reduced, on the one hand due to the high moment of inertia of wheel  62 , and on the other hand due to the very small displacement of the animation part with each alternation of the balance wheel. 
     In order to prevent the gear shakes of the animation train from generating random movements of the animation part, it may be possible to equip the latter with a brake working upon the end of a pivot of its shaft. 
     In the examples described above, the control element for the animation part may be of the crank type. The same effect could be obtained by means of a cam and a lever resting against the cam. 
     Thus, by virtue of the particular characteristics exhibited by the movement according to the exemplary embodiments of the invention, it may be possible to realize a watch equipped with a slow animation that may bring a touch of serenity and calm, contrasting with the normal conditions of everyday life, and thus offering a little bit of calm to the wearer, even when he reads the time. Moreover, the presence of a wheel train may allow the pivot point of the animation part to be placed almost anywhere, and especially in the immediate vicinity of the center of the movement, which may provide the watch with an original aesthetic appearance.