Abstract:
The invention relates to a ringing mechanism comprising a power source ( 10 ) for driving rakes ( 18 ) and a gear ( 12 ) connecting the power source ( 10 ) to a regulation member ( 14 ), characterised in that the rakes ( 18 ) are kinetically connected to the power source ( 10 ) through a differential ( 20 ) provided in the gear ( 12 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to the field of mechanical horology. It more particularly concerns a ringing mechanism comprising a power source for driving rakes and a gear connecting the power source to a regulation member. 
       PRIOR ART 
       [0002]    This type of device is known, in particular in watches called grand strikes. These watches offer the possibility of ringing the passing hours, i.e. all of the quarters and/or all of the hours automatically. It is therefore obvious that, in order to do this, the wearer does not need to wind a barrel for each ringing, as is the case in the most common minute-repeaters, which only ring the hour on request and in which a ringing barrel is wound via a rack when the user actuates the control bolt. 
         [0003]    Grand strikes are therefore equipped with a complete gear for driving the ringing parts. This gear therefore connects a ringing barrel provided with its own winding system to a regulation member. The barrel provides power to the ringing parts via a control and distribution member arranged in the gear, possibly coaxially to the barrel. The control and distribution member comprises a stack of several wheels, free or integral in rotation in relation to each other. Without explaining this device in detail, which is completely described in the work “Les montres compliquées” by F. Lecoultre, in Editions Horlogères, pages 182-205, we can summarize that clicks arranged in this member and controlled by levers make it possible to manage the various steps of the progress of the ringing. 
         [0004]    The aim of the present invention is to propose an advantageous alternative to the devices of the prior art. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0005]    More precisely, in a ringing mechanism according to the concerned invention, the ringing parts are kinematically connected to the power source via a differential provided in the gear. 
         [0006]    Advantageously, this differential comprises a first input wheel kinematically connected to the gear and a second input wheel connected to a control member, and an output wheel connected to the ringing parts. 
         [0007]    The control member is arranged such that the differential can occupy:
       a first configuration in which the first input wheel is blocked in rotation and the second input wheel is free in rotation, the output wheel being free in rotation,   a second configuration in which the first input wheel is free in rotation, the second input wheel is blocked in rotation, the output wheel then being free to be driven via the first input wheel, and   a third configuration in which the first and the second input wheels are blocked in rotation, the output wheel also being blocked in rotation.       
 
         [0011]    In one preferred embodiment, the differential comprises:
       a first solar wheel constituting the first input of the differential and kinematically connected with a wheel of the gear,   at least one lower satellite meshing with the first solar wheel,   a satellite-holder wheel free in rotation and coaxial with the solar wheel, constituting the second input of the differential, said lower satellite being mounted in rotation on a first level of the satellite-holder wheel,   at least one upper satellite mounted in rotation on a second level of the satellite-holder wheel, mounted coaxial and integral in rotation with the lower satellite,   an upper solar wheel, meshing with the upper satellite and constituting the output of the differential.       
 
         [0017]    Preferably, the control member is a camshaft comprising a first cam to block the first input wheel or leave it free in rotation, a second cam to block the second input wheel or leave it free in rotation and at least one drive train for the pivoting of the shaft. 
         [0018]    In order to offer the user the possibility of deactivating the ringing, the mechanism can comprise a silencing device provided with a bolt which can evolve between first and second positions, in which it cooperates with the drive train in order to block the control member. This bolt can be moved by manual control means, activated by the wearer, or by automatic control means, for example to prevent ringing from triggering itself below a certain power reserve as a time goes by. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    Other characteristics will appear more clearly upon reading the following description, done in reference to the appended drawing, in which: 
           [0020]      FIG. 1  is an overall view of the ringing mechanism, its power source and the gear connecting them, 
           [0021]      FIG. 2  is a cross-sectional view of the differential preferably used in the mechanism according to the invention, 
           [0022]      FIGS. 3 to 6  are views of the control member which governs the different positions of the differential, and 
           [0023]      FIG. 7  shows different possibilities and safety devices which the system may comprise. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    The different elements described and/or shown are mounted on a frame made up of a plate and bridges. In order to facilitate reading of the drawings, the plate, bridges and pivots are not illustrated. 
         [0025]      FIG. 1  shows a barrel  10  whereof the winding system has not been illustrated, which drives a reduction gear train  12 , which ends with a regulation member, for example a flywheel  14  provided with an inertia-block brake as known by those skilled in the art. 
         [0026]      FIG. 1  also illustrates ringing parts comprising:
       a series of snails  16  driven by the basic movement of the timepiece in which the mechanism is mounted, and supplying information on the current time, and   rakes  18  arranged to cooperate with these snails  16  in order to actuate hammers striking on gongs in order to produce a ringing identifying the current time.         
         [0029]    This mechanism not being directly the object of the invention, it will not be described in detail. One may refer to application EP 06121650.3, which describes it completely. The rakes could also be part of a more conventional mechanism as described in the aforementioned work or in the book “Théorie de l&#39;horlogerie” by Reymondin et al, Fédération des Ecoles Techniques, 1998, ISBN 2-940025-10-X, pages 219 to 224. 
         [0030]    Particularly to the invention, a differential  20  kinematically connects the gear  12  to the rakes so that they are driven by the barrel  10  during the ringing. 
         [0031]    An example of differential  20  particularly adapted to the invention is shown in  FIG. 2 . On an arbor with an axis A-A, it comprises a first solar wheel  22  constituting a first input of the differential and kinematically connected with a wheel of the gear  12 . According to the example, the differential  20  is coaxial to and integral with this wheel of the gear  12 . This solar wheel  22  meshes with at least one, typically three, lower satellites  24  mounted in rotation on a first level of a satellite-holder wheel  26  provided with a peripheral toothing. The latter constitutes a second input of the differential. It is free in rotation and coaxial with the solar wheel  22 . The three lower satellites  24  are each mounted coaxial to and integral in rotation with at least one, typically three, upper satellites  28  mounted in rotation on a second level of the satellite-holder wheel  26 . The upper satellites  28  mesh with an upper solar wheel  30 , coaxial to and integral in rotation with a setting-wheel  32 . This upper solar wheel  30  constitutes the output of the differential. 
         [0032]    As one can see in  FIG. 1 , this setting wheel  32  is engaged with a toothed sector  34  of an hour feeler-spindle, designed to cooperate with the hour snail. An hour ratchet  36 , designed to actuate a lift in order to strike the hours, is also integral in rotation with the setting wheel  32 . The hour ratchet  36  is therefore directly kinematically connected to the hour feeler-spindle. 
         [0033]    Thus, it appears that the differential can occupy three different useful configurations by acting on the two inputs. 
         [0034]    A first configuration in which the satellite-holder wheel  26  is free in rotation and in which the lower solar wheel  22  is blocked: the upper solar wheel  30  and the elements integral therewith are free to turn. The satellites  24  and  28  indeed turn around the axis A-A of the differential  20  because the lower satellites  24  roll on the lower solar wheel  22 , which is blocked. 
         [0035]    A second configuration in which the satellite-holder wheel  26  is blocked in rotation and the lower solar wheel  22  is free to be driven by the train  12 : the upper solar wheel  30  is then free to be driven by the train. Indeed, in this case, the satellites behave like a simple vertical setting wheel and transmit the rotation of the lower solar wheel  22  to the upper solar wheel  30 . 
         [0036]    A third configuration in which the satellite-holder wheel  26  and the lower solar wheel  22  are blocked in rotation: the upper solar wheel  30  is also blocked, because of this, in rotation. The satellites  24  and  28  cannot, in this case, turn on themselves or turn around the axis A-A of the differential. 
         [0037]    One therefore understands that, in the first configuration above, the rakes  18  kinematically connected to the hour feeler-spindle can move independently of the train  12  and the barrel  10 . This configuration is that which is used, during triggering of the ringing, to allow the feeler-spindles of the different rakes to fall on their respective snails in order to get information relative to the current time. The second configuration makes it possible to kinematically connect the barrel  10  to the rakes  18 . It is therefore this configuration which is used during the progress of the ringing so that the rakes move relative to their lift in order to actuate the hammers. Lastly, the third configuration corresponds to the situation in which the rakes  18  are stopped and kept locked. 
         [0038]    As one will understand better in the continuation of the description, the blockage of the lower solar wheel  22  is done, according to the preferred embodiment illustrated in the drawings, by blocking the unwinding of the ringing barrel  10 . Advantageously, this blockage is obtained by a banking element  38  arranged so as to evolve between first and second extreme positions, the stop element  38  crossing, in one of these extreme positions, the journey of a pin  40  mounted protruding on the regulation member  14 . It is in fact at this location of the gear that the torque is the least significant and the blockage can be done with optimal security. These elements are visible in  FIG. 6  and their actuation will be described below. 
         [0039]    One can see in  FIG. 3  that the blockage of the satellite-holder wheel  26  is done directly via a bolt  42 , having the form of a hook  42   a  arranged on a lever  42   b  and capable of evolving between first and second extreme positions, the hook  42   a  cooperating with the toothing of the satellite-holder wheel  26  when it is found in one of these extreme positions. 
         [0040]    We will now examine the manner in which the banking element  38 , on one hand, and the bolt  42 , on the other hand, are controlled so that they each evolve between their first and second extreme positions, in a coordinated manner. 
         [0041]    A camshaft  50 , particularly visible in  FIG. 3 , is mounted pivoting in the frame and comprises a first cam  52  designed to control the blocking of the lower solar wheel  22  and a second cam  54  controlling the blocking of the satellite-holder wheel  26 . 
         [0042]    The cams and the stars are shown individually in  FIG. 4 . The camshaft  50  is positioned by a first star  56  comprising a first level  56   a  ( FIG. 4   a ) provided with twelve teeth cooperating with a jumper  58  and a second level  56   b  ( FIG. 4   b ) only comprising four teeth, regularly distributed on a cutting of twelve teeth and superimposed with the teeth of the first level. This star  56  also performs the function of drive train for the shaft  50 , as will be described in detail below. 
         [0043]    Because the operation of the differential involves three configurations, the positioning star  56  is numbered according to a multiple of three, twelve having an advantageous angular pitch between two consecutive positions in relation to the size of these parts and the available space. 
         [0044]    The first cam  52 , shown in  FIG. 4   c , has a succession of protruding parts and hollow parts. As mentioned above and illustrated by  FIG. 6 , blocking of the lower solar wheel  22  is done at the regulation member  14 . The banking element  38  can be arranged at the end of a double lever  58 , comprising two levers  58   a  and  58   b  articulated with each other by a post  58   c  integral with one of them  58   a  and cooperating with a housing  58   d  arranged in the other  58   b . A spring  60  is arranged so as to push the end of the lever  58   a  against the first cam  52 . The pivot points of the double lever  58  are arranged, in the example, such that, when the lever  58   a  pushes against a protruding part of the cam  52 , the banking element  38  cooperates with the regulation member  14 , which blocks the lower solar wheel  22 . Conversely, when the cam  52  has a hollow part at the lever  58   a , the lower solar wheel  22  is free. Thus, for a ringing cycle, the cam  52  is provided with a succession of a protruding part, a hollow part and a protruding part, this series being repeated four times according to the example of a twelve-position camshaft  50 . 
         [0045]    The second cam  54  ( FIG. 4   d ) also has a succession of protruding parts and hollow parts. A spring  62  is arranged so as to push the end of the lever  42  not bearing the hook  42   a  against the cam  54 . In the example, the pivot point of the lever  42  is arranged such that, when the cam  54  has a protruding part at the lever  42 , the hook  42   a  is outside the toothing of the satellite-holder wheel  26  which is therefore free in rotation. Conversely, when the lever  42  pushes against a hollow of the cam, the satellite-holder wheel  26  is blocked. Thus, for a ring cycle, the cam  54  is provided with a succession of one protruding part and two hollow parts, this series being repeated four times according to the example of a twelve-position camshaft. 
         [0046]    One skilled in the art will know how to coordinate the two cams so as to have the following positions: 
         [0000]    
       
         
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Lower solar 
                   
                 Satellite- 
               
               
                 Configuration 
                 First cam 
                 wheel 
                 Second cam 
                 holder wheel 
               
               
                   
               
             
             
               
                 1 
                 Protruding 
                 Blocked 
                 Protruding 
                 Free 
               
               
                 2 
                 Hollow 
                 Free 
                 Hollow 
                 Blocked 
               
               
                 3 
                 Protruding 
                 Blocked 
                 Hollow 
                 Blocked 
               
               
                   
               
             
          
         
       
     
         [0047]    In order to explain how the camshaft  50  is driven to go from one configuration to the other, we will start from configuration  3  in which the rakes  18  are locked. The passage to configuration  1  takes place upon triggering of a ringing, either as the time passes, or upon request. 
         [0048]    For triggering upon passage, one can refer to  FIG. 3 , which shows a flexible finger  70  designed to cooperate with the second level  56   b  of the star  56  and driven in rotation by the basic movement of the timepiece. For example, the finger  70  performs one to-and-fro motion under the action of a socket  72  whereof the perimeter defines a sort of snail and comprises a slanted plane  72   a . The finger  70  is kept pushed against the cam by a spring  74  at a lug  70   a  with which it is provided. The socket is driven, in the counterclockwise direction in relation to  FIG. 3 , by the minute wheel of the basic movement, at a rate of one revolution per hour, which causes the finger  70  to pivot in the counterclockwise direction and wind the spring  74 . Every hour, as the hour passes, the lug passes the slanted plane and the finger  70 , under the effect of the spring  74 , pivots in the clockwise direction and drives the star  56  by one pitch, thereby causing the differential to pass to configuration  1 . 
         [0049]    The socket  72  could thus comprise a plurality of slanted planes so as to actuate the finger every quarter hour, to ring the quarters, a lifting-lever then possibly being provided if it is desired that the hours not be struck upon striking of the quarters. 
         [0050]    For a manual triggering, we will refer to  FIG. 5 . It is proposed that the user actuate a bolt  76  integral with a rack  78 , like a conventional minute repeater. The rack  78  meshes with an outer toothing of a ring  80 , coaxial with the ringing barrel  10 . This ring  80  is connected to the arbor of the barrel  10  by a radial spring  82  having a hub  82   a  mounted square on the arbor and typically two elastic blades  82   b , exerting radial pressure toward the outside of the wheel and ending with a toothed portion cooperating with an inner toothing comprised by the ring  80 . The spring  82  and the inner toothing of the ring  80  are arranged so as to form a click between the arbor of the barrel  10  and the rack  78 . Thus, pivoting of the ring  80  in one direction drives the barrel arbor in rotation, but neither the pivoting of the barrel arbor in the other direction, for example during disassembly of the movement, nor driving of the arbor during manual winding of the ringing barrel causes movement of the bolt  76 . 
         [0051]    The outer toothing of the ring  80  transmits the movement of the bolt to a wheel  84  with which it meshes. This wheel  84  is provided with a return system  86 , for example a balance spring, allowing the bolt  76  to return to its locked position since the aforementioned click system does not allow this return to be ensured by the power supplied by the barrel  10 , as is the case in classic repeaters. The wheel  84  also supports an arm  88  mounted on its axis and ending with a support zone  88   a  designed to cooperate with a second star  90  ( FIG. 4   e ), also playing the role of drive element for the arbor  50 , in order to advance the camshaft  50  by one pitch and cause the differential to go to configuration  1 . This star  90  is sized on the number twelve but only comprises four teeth, i.e. one per ringing cycle. It is also very visible in  FIG. 7 . 
         [0052]    This manual trigger device is the object of a patent application having the same filing date as this application and in which it is described in more detail. 
         [0053]    In a simplified version, one may provide that a simple lever driven by a button arranged in the middle of the watch drives the star  90  by one pitch, without rewinding the barrel. 
         [0054]    For the passage of the camshaft to position  2 , the teeth of the star  90  are capable of crossing the path of a transmission wheel  92 , put in continuous rotation by the main train of the movement. Typically, this wheel is driven by the third wheel at a rate of one revolution in approximately thirty seconds. One skilled in the art will know how to determine the shape of the teeth of the star  90  and of the transmission wheel  92  in order to ensure good transmission of the torque. 
         [0055]    More particularly, the teeth of the star  90  are arranged on the camshaft so as to cross the path of the transmission wheel  92  when the differential is in its first configuration. The camshaft  50  is therefore driven slowly by one pitch and causes the differential  20  to pass to configuration  2 . 
         [0056]    One will recall that, in configuration  2 , the rakes  18  are kinematically connected to the barrel  10  so as to allow the progress of the ringing as such. The shaft  50  must therefore advance one additional pitch only at the end of the ringing. 
         [0057]    In order to do this, one of the rakes  18 , preferably the minute rake  18   a , since it is the last part which comes into play in the ringing, or a part which is kinematically connected thereto, allows the movement of a transmission element at the end of the ringing. In reference to  FIG. 5 , this element can be a finger  94  arranged so as to cooperate with the first star  56  in order to cause the camshaft  50  to advance by one pitch. In this case, the minute rake  18   a  supports a pin  96  designed to drive the finger  94 . Advantageously, this finger  94  is located at the end of an elastic portion of a lever  98 , which improves the safety of the device. A spring  99  keeps the lever  98  bearing against the pin  96 . Thus, at the end of ringing, the camshaft  50  advances one pitch, which allows the differential to go to configuration  3 . A new ringing cycle can begin. 
         [0058]    To summarize, when the ringing is idle, the differential  20  is in its configuration  3 , the barrel  10  being locked, and the rakes  18  thus being held in position. When the ringing is triggered, either manually or due to the passage of time, the camshaft  50  is driven by one pitch, which allows the differential  20  to be brought to its configuration  1 . The rakes are then disconnected from the ringing gear  12  and they can then fall freely, under the effect of their respective springs, on their snails in order to get information relative to the current time. This step is very fast and takes place while the transmission wheel  92  drives the second star  90  and causes the differential  20  to pass to its configuration  2 . The rakes are then kinematically connected to the barrel  10 , which is released. The direction of movement of the rakes then reverses and their toothed sector actuates the lifts and the hammers in order to produce the ringing. Lastly, at the end of the ringing, the pin  96  causes the camshaft  50  to advance one additional pitch such that the mechanism is again in its locked position. 
         [0059]    One will note that, thanks to the fact that the finger  70  cooperates with the second level  56   b  of the star  56 , if a triggering due to the passage of time occurs during the progress of a ringing which has just been triggered manually, then the finger  70  will only find a space without teeth on its path and will not abut against the camshaft. This security is particularly advantageous because attempting to trigger ringing due to the passage of time while ringing is already in progress would cause serious damage to the mechanism. 
         [0060]    The same effect is obtained for manual triggering thanks to the structure of the star  90 . If manual triggering takes place during the progress of ringing which has just been triggered manually or due to the passage of time, then the arm  88  will only find a space without teeth on its path and will not abut against the shaft  50 . Combined with the manual winding system described above, it is even possible to wind the barrel  10  only via the bolt, either during ringing, or by adjusting the path of the bolt so as not to trigger ringing. 
         [0061]    The mechanism according to the invention can, furthermore, comprise a silencing device  100  illustrated in  FIG. 7  and which allows the user to prevent triggering of the ringing due to the passage of time. To this end, a button or a corrector (not shown) is arranged in the middle of the watch and causes a slide-way  102  to evolve between a first, idle position and a second position. This slide-way  102  is mounted mobile in translation on the plate of the ringing mechanism and comprises, for this purpose, two oblong parts  102   a  in which shouldered screws pass. 
         [0062]    The slide-way  102  cooperates with a post  104  arranged on a lever  106 . A bolt  108  is mounted pivoting, coaxial to the lever  106 . The bolt  108  is arranged so as to be able to evolve between a first, idle position and a second position in which it cooperates with the second star  90 , in order to prevent the rotation of the shaft  50 . More particularly, the bolt  108  has a hollow which substantially fits the circumference of the camshaft. The hollow defines a finger  108   a  capable of interacting with the teeth of the star  90 . These teeth are formed so as to bear substantially orthogonally on the finger  108   a , in order to obtain effective blocking. 
         [0063]    The bolt  108  is provided with a pivot-shank  110  capable of cooperating with a support surface  106   a  presented by the lever  106 . A first spring  112  keeps the pivot-shank  110  bearing against the surface  106   a . The force exerted by this spring  112  on the bolt tends to distance the camshaft  50  and bring it back to its first position. A second spring  114  is arranged so as to stick the lever  106  against the slide-way  102 . 
         [0064]    In the illustrated embodiment, the finger  108   a  blocks the rotation of the shaft  50  when the slide-way  102  is pulled, i.e. when it is in its most distant position in relation to the shaft  50 . The extreme positions of the slide-way  102  can be marked by a notch system, advantageously obtained at the corrector or the button. Thus, when the user actuates the corrector so as to pull the slide-way  102 , the lever  106  pivots and, the spring  112  being weaker than the spring  114 , the bolt  108  is brought into its second position and blocks the pivoting of the camshaft  50 . Inversely, when the slide-way  102  is pushed, the bolt  108  returns to its first position under the effect of the spring  112 , releasing the camshaft  50 . 
         [0065]    Thanks to the fact that the bolt  108  and the lever  106  are not integral, the bolt  108  can be brought into its second position by another device. Thus, a second lever  116  is also mounted coaxial in relation to the first. This second lever  116  is provided with a feeler-spindle  116   a  maintained by a third spring  118  bearing against a cam  120  performing one revolution, substantially in a time period equal to the power reserve of the ringing barrel  10 . The cam  120  has a hollow arranged so as to be present at the lever when the power reserve of the barrel is below a predetermined threshold. 
         [0066]    When the power reserve of the barrel  10  falls below this predetermined threshold, the lever  116  pivots and, the spring  112  being weaker than the spring  118 , the bolt  108  is brought into its second position and blocks the pivoting of the camshaft  50 . Inversely, when the power reserve returns above the predetermined threshold, the bolt returns to its first position under the effect of the spring  112 , releasing the camshaft  50 . 
         [0067]    In the case where the manual triggering system for the ringing makes it possible to rewind the ringing barrel  10 , it is useful to provide that the ringing can take place, even if the silencing device  100  is set. To this end, upon manual triggering, the arm  88  actuating the star  90  is arranged so as to cross, in its journey, the bolt  108  if the latter is in its second position, so as to bring it into its first position for the time needed to cause the shaft  50  to advance. This release must take place before the arm  88  exerts a push on the star  90 . Then, once the shaft has pivoted, given that the bolt is found across from portions of the star  90  without teeth, it no longer exerts blocking, until, at the end of the ringing, it cooperates with a next tooth. 
         [0068]    One skilled in the art may provide other cams to actuate the silencing device. For example, a cam driven by the gear of the basic movement at a rate of one revolution per twenty-four hours can define parts of the day during which ringing due to the passage of time is triggered and others, for example during the night, during which it is blocked. 
         [0069]    Thus is proposed a new ringing mechanism making it possible to manage the different steps of the progress of the ringing, particularly in a grand strike, i.e. in a striking-mechanism making it possible to strike the hours due to the passage of time or upon request. The embodiment presented above is only a non-limiting illustration of the invention, the main aspect of which is to use a differential to manage the steps of the ringing. One skilled in the art can easily adapt various connecting elements between the control member and the inputs of the differential without going beyond the scope of the invention. He may also find solutions other than those proposed in order to make the camshaft advance. Thus, instead of using a transmission wheel to cause the shaft to go from its first to its second configuration, one can provide for performing this driving via a transmission element connected to the rake, like the finger  94 , driving the shaft once the rakes have fallen on their snails.