Patent Document

TECHNICAL FIELD 
       [0001]    The present invention relates to hour indicating ringing mechanisms, whether in passing or of the repetition type. 
       BACKGROUND OF THE INVENTION 
       [0002]    Such ringing mechanisms are well known by those skilled in the art. They make it possible to indicate the time with sounds, through a succession of notes struck on gongs. Such watches comprise a power source and a ringing device and are, for example, described in the work entitled “Les montres compliquées” by François Lecoultre, Editions horlogéres, Bienne, 1951. 
         [0003]    Such mechanisms require significant settings, in order to ensure a high sound quality while requiring only a very small amount of power. One of the most delicate settings concerns adjusting the frequencies of the blows struck. This setting is obtained by a speed regulator connected to the power source by a gear. In the known systems, the regulator may be of the type with a flywheel or comprise a recoil pallet cooperating with a ratchet wheel whereof the working conditions define the frequency of the striking. The amplitude of the pallet is defined by an eccentric mounted with hard friction on the frame. The greater the amplitude, the lower the frequency of the blows. Adjusting the frequency is therefore done at the end of the kinematic chain, on the organ ensuring the stability of the frequency of the sound signal. 
         [0004]    This setting is done by a watchmaker, during manufacturing, and involves relatively delicate operations. If the wearer wants a slower or faster signal, or if other factors have led to a modification of the signal frequency, it is then necessary to call on a specialist. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0005]    The aim of the present invention is to offset these drawbacks. This aim is achieved thanks to the fact that the mechanism comprises, moreover, a speed adjuster, as defined in the claims. Thanks to this, the frequency of the blows can be adjusted easily and more precisely. 
         [0006]    The present invention also concerns a ringing watch movement equipped with a mechanism according to the invention, as well as a watch provided with a movement of this type. This watch also comprises a case provided with a control member accessible from the outside and cooperating with the control means. In this way, the user himself can change the frequency of the ringing, without having to open the case. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The invention will be better understood upon reading the description which follows, given as an example and done in reference to the appended drawing in which: 
           [0008]      FIGS. 1 and 2  illustrate, in flat view and cross-section, respectively, the schematic diagram of a first embodiment of a mechanism according to the invention, in a first working position; 
           [0009]      FIG. 3  is a flat view of the mechanism of  FIGS. 1 and 2 , in a second working position, 
           [0010]      FIGS. 4 and 5  illustrate, in cross-section, a speed changing organ according to a second embodiment, in two extreme positions, while  FIG. 6  shows this organ from the top, in the position corresponding to  FIG. 5 , 
           [0011]      FIG. 7  diagrammatically shows different possible configurations to ensure the change of frequency of the ringing, and 
           [0012]      FIGS. 8 and 9  show, in cross-section and top view, a third embodiment, and 
           [0013]      FIG. 10  illustrates a detail of this third embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    The first embodiment of the mechanism according to the invention is illustrated in  FIGS. 1 to 3 ; it essentially comprises, arranged on a frame (not shown) and which supports bearings designed to allow pivoting of the mobile parts:
       a gear  10 , mounted pivoting on the frame,   a power source made up of a barrel  12 ,   a speed regulator  14  primarily made up of a flywheel connected to the barrel  12  by the gear  10  for which it ensures regulation of the rotational movement, and   a speed adjuster  16  integrated to the gear  10 .       
 
         [0019]    The barrel  12  comprises ( FIG. 2 ) a drum  12   a , an arbor  12   b  mounted pivoting on the frame and on which the drum  12   a  can turn, and a spring  12   c  housed inside the drum  12   a  and connected thereto by its outer end and to the arbor by its inner end. 
         [0020]    The arbor  12   b  supports, integral in rotation, a wheel  18  provided with wolf teeth. A wheel  20  is mounted idle on the arbor  12   b . It supports a spring pawl  22  engaged in the toothing of the wheel  18 . It is provided with an outer toothing  20   a , forming the first wheel of the gear  10  and designed to cooperate with the device  16 , as will be explained later. 
         [0021]    The adjuster  16  comprises a wheel assembly  24  mounted pivoting on the frame and a lever  26  integral with the arbor of the wheel assembly  24  and which can go from one to the other of the two positions illustrated in  FIGS. 1 and 3 . The lever  26  also supports two wheel assemblies  28  and  30  each comprising a wheel and a pinion. These wheel assemblies mesh continuously via their wheel with the wheel assembly  24 , while the pinions of the wheel assemblies  28  and  30  mesh respectively with the wheel  20  depending on whether the lever  26  occupies the positions illustrated in  FIGS. 1 and 3 . 
         [0022]    The number of teeth comprised by the wheels of the wheel assemblies  28  and  30  are different. In the example illustrated in the drawing, the wheel of the wheel assembly  28  comprises twenty-four teeth, that of the wheel assembly  30 , twenty-seven. As all of the other components of the kinematic chain between the barrel  12  and the speed adjuster  14  do not change, the gear ratio between the configurations illustrated in  FIGS. 1 and 3 , respectively, is  9 / 8 . 
         [0023]    The gear  10  also comprises three wheel assemblies  32 ,  34 ,  36 . The pinion of the wheel assembly  32  is driven by the wheel of the wheel assembly  24 , while the wheel of the wheel assembly  36  drives the flywheel. 
         [0024]    The gear  10  also comprises at least one wheel assembly (not shown) meshing with the wheel  20  and connected to a control device actuating a hammer designed to strike on a gong, at given moments. This part of the mechanism is well known by those skilled in the art. It is in particular described in the work previously mentioned. 
         [0025]    The frame supports two banking elements  38  cooperating with a positioning member  40  to allow the lever  26  to be able to occupy two stable positions, illustrated in  FIGS. 1 and 3 , respectively. Without there being a need to describe them further, one skilled in the art will be able to choose the technically suitable solution to produce the banking elements and the positioning organ. 
         [0026]    Thus, for an average winding of the barrel spring, the ringing has a duration of approximately 18 seconds when the gear  28  is engaged with the wheel  20 , and 20 seconds, when the gear  30  meshes with the wheel  20 , or a gap of approximately two seconds between the two positions. 
         [0027]      FIGS. 4 to 6  show another type of adjuster  42 , with ball bearing, designed to replace the adjuster  16  previously described. The mechanism of  FIGS. 1 to 3  equipped with an organ of this type corresponds to a second embodiment. This adjuster is, as shown in  FIG. 5 , adjusted such that the flywheel constituting the speed adjuster  14 , has a maximal speed, and in  FIG. 4  a minimal speed. 
         [0028]    The adjuster  42  comprises:
       an arbor  44  mounted pivoting on the frame, defining an axis AA and provided with a collar  44   a  at one of its ends,   an output wheel  46  engaged with the gear  32 , fixed rigidly on the arbor  44  and provided with a first cylindrical portion  46   a  whereof the free end is truncated to form a first conical surface  46   b,      an input wheel  48  engaged with the wheel  20 , mounted pivoting and sliding on the arbor  44 , provided with a second cylindrical portion  48   a  oriented toward the wheel  46  and with the same outer dimension as the cylindrical portion  46   a , and forming a second conical surface  48   b,      an intermediate stone  50 , bearing against the collar  44   a ,   a socket  52  mounted pivoting on the arbor  4 , bearing against the stone  50 ,   a spring  54  arranged between the socket  52  and the turning-arbor  48   a , and tending to push the wheel  48  toward the wheel  46 ,   a ball bearing  56  comprising balls  58 , a frame  60  provided with a third conical surface  60   a , and a ring  62  in which are engaged the turning-arbor  48   a  and the cylindrical portion  46   a , the balls  58  being arranged so as to be in contact with the conical surfaces  46   b ,  48   b  and  60   a , and positioned by the ring  62 ,   a control carriage  64  connected to the arbor  60  and mounted on the frame so as to be able to move along a direction parallel to the axis AA,   a control organ arranged so as to allow the movement of the carriage  64  between first and second extreme positions, defined by bankings, respectively, and corresponding to the maximum and minimum run times of the ringing.       
 
         [0038]    As one can see more particularly in  FIGS. 4 and 5 , the ring  62  is mounted pivoting and sliding on the cylindrical portions  46   a  and  48   a . It angularly positions the balls  58  in relation to each other, while allowing them to roll and move radially. 
         [0039]    The conical surface  46   b  has an apex angle different from that of the conical surface  48   b . In the example, the apex angle defined by the surface  46   b  is smaller than that defined by the surface  48   b.    
         [0040]    The conical surfaces  46   b ,  48   b  and  60   a  respectively form first, second and third rolling surfaces for the balls  58 . Unlike a conventional ball bearing, one will note that the conditions for friction between the balls and the rolling surfaces must allow the balls to roll and not slide on the surfaces  46   b ,  48   b  and  60   a . In this way, the input wheel drives the output wheel. Because the angles of the conical surfaces are different, the points of contact of the balls with the conical surfaces  46   b  and  48   b  are located at different distances from the axis AA; the rolling paths of these balls therefore are not the same length. This causes a speed differential between the input wheel and the output wheel, variable according to the position of the respective contact points of the balls with the conical surfaces  46   b  and  48   b  and also according to the apex angles defined by these surfaces. 
         [0041]    By acting on the control organ so that the wheel reaches its maximal speed and therefore, the duration of the ringing is minimal, the frame  60  is moved along a direction parallel to the axis of the arbor  44 , in the direction of the wheel  48 . The wheel  48  is then pushed back, the spring  54  being compressed. This situation is illustrated in  FIG. 5 . For an average winding of the barrel spring, the ringing then lasts approximately 15 seconds. 
         [0042]    By acting on the control organ so that the wheel reaches its minimal speed and therefore, the duration of the ringing is maximal, the spring  54  causes the cylindrical portion  48   a  to penetrate the cylindrical portion  46   a , pushing the balls  58  radially outward, which increases the ratio between the speed of the input wheel  58  and the output wheel  46 . This situation is illustrated in  FIG. 4 . For an average winding of the barrel spring, the ringing then lasts approximately 17 seconds, or 2 seconds longer than in the position of  FIG. 5 . 
         [0043]    Advantageously, the control organ can be stabilized at each position between the first and second extreme positions. In this way, the duration of the ringing can be adjusted continuously, between the maximum and minimum durations. 
         [0044]    The control organ can, for example, be a worm screw accessible from the inside of the watch case, so as to be able, using a screwdriver, to adjust the duration and frequency of the hour ringing. 
         [0045]    One will note that the control organ could also act on the position of one of the input or output wheels, an elastic organ maintaining the conical surface of the frame  60  in contact with the balls. 
         [0046]      FIG. 7  diagrammatically illustrates the manner in which the speed adjuster can be integrated into the gear  10 , in a watch equipped with a speed regulator, of the flywheel type for example. In this diagram, one can see the power source  12 , the speed regulator  14  and the ringing device  68  diagrammatically illustrated by rectangles. They are connected to each other by the gear  10 , which comprises three branches  10   a ,  10   b  and  10   c , connected to the power source  12 , the speed regulator  14  and the ringing mechanism  68 , respectively. In this mechanism, the speed adjuster  16  can be placed in one or the other of the three locations, identified  16   a ,  16   b  and  16   c , or on the branch  10   a , the branch  10   c  and at the intersection of the three branches. 
         [0047]    If the mechanism according to the invention was provided with a substantially isochronous speed regulator, it would then be possible to place the adjuster at positions  16   b  or  16   c , or on the branch  10   b.    
         [0048]      FIGS. 8 to 10  show a third embodiment of a speed adjuster according to the invention. The essential device of this variation is the flywheel ending the striking gear and constituting the speed regulator  14 . The rest of the ringing gear connecting the barrel to the flywheel is conventional. 
         [0049]    The flywheel comprises an arbor  70 , pivoting on elements of the frame and kinematically connected to the ringing barrel  12 . This arbor serves as a pivot axis BB for a plate  72  on which arms  74  ending by rubbing organs  76 , for example stones, are pivoted. Light springs  78  slightly stress the arms by pushing them toward the center of the plate  72 . An annulus  80  mounted on the frame is arranged concentrically to the arbor  70 . It surrounds the arms  74  and is located in the plane of the rubbing organs  76 . 
         [0050]    Like a traditional flywheel, when the ringing mechanism is in operation, the arbor  70  is driven in rotation and with it, the plate  72 . Under the effect of the centrifugal force, the arms  74  oscillate around their pivot point and the rubbing organs  76  come into contact with the ring and rub against it. By reaction and under the effect of the springs, the arms  74  pivot and the frictional organs  76  move toward the arbor  70 , before coming back, under the effect of the centrifugal force, into contact again with the ring  80  and so on. The arms thus describe an oscillating movement in a plane perpendicular to the axis BB, which causes the inertia of the wheel to vary. Moreover, the rubbing organs intermittently come into contact with the ring. This makes it possible to adjust the unwinding speed of the ringing barrel and therefore the frequency with which the blows to the ringing mechanism are struck. 
         [0051]    The ring  80  defines an inner wall  80   a  which, according to the invention, has a variable diameter. Preferably, the variation of the diameter is continuous such that this inner wall  80   a  is tapered. The relative position of the rubbing organs  76  and the ring  80  along the axis BB is adjustable. Thus, the rubbing organs can come into contact with the ring at different levels in reference to the axis BB. The contact point between the organs and the ring can therefore be located at different distances in relation to the center of the ring  80 . 
         [0052]    In order to vary the relative position of the rubbing organs  76  and the ring  80  along the axis BB, the embodiment illustrated in the drawing proposes the ability to move the ring along the axis BB. To do this, the ring is placed on a support formed by a positioning lever  82 , particularly illustrated in  FIG. 10 . Pins  84  are positioned in the frame so as to vertically guide the ring  80  and ensure its position in relation to the axis BB. At least one spring organ (not shown) exerts a force on the ring tending to push it against the lever. 
         [0053]    The positioning lever is in contact with the ring in two areas, defining a chord in relation to the circle formed by the ring  80 . The lever comprises a first pair of surfaces  82   a , located in a first plane and separated from each other by a distance equal to the cord defined above. Thus, when the ring is pushed on the first pair of surfaces  82   a , the rubbing organs  76  can come into contact with the inner wall  80   a  of the ring at a first level, in points located at a first distance in relation to the center of the ring. 
         [0054]    The lever comprises a second pair of surfaces  82   b , located in a second plane different from the first in reference to the ring and also separated from each other by a distance equal to the chord. Thus, when the ring  80  is pressed on the second pair of surfaces  82   b , the frictional organs  76  can come into contact with the inner wall of the ring at a second level, in points located at a second distance in relation to the center of the ring. 
         [0055]    The lever  82  is mounted mobile in relation to the ring and can move between first and second positions, in which the latter part is pushed on the first or the second pair of surfaces, respectively. The lever can be actuated from the outside of the watch by its wearer. Advantageously, the lever  82  is arranged such that its first and second positions are marked and stabilized by a notch. To do this and according to the illustrated example, the lever  82  comprises an elastic portion  82   c  provided with two housings  82   d , capable of cooperating with a fixed element, such as a pin  83 , fixed on the frame. Preferably, the elastic portion  82   c  can be formed such that the pin can only be positioned in the zone defined by the two housings. To this end, the edge of each of the housings  82   d , located opposite the other housing, is high enough that, despite the elasticity of the zone, the fixed pin  83  cannot cross it. The elastic zone  82   c  is formed such that, if the pin is bearing between the two housings, it returns into position in one or the other of the housings. One thus obtains a jumper spring function, i.e. the lever  82  can only be in its first or second positions. 
         [0056]    One therefore has, side by side on the lever, a surface which is part of the first pair  82   a  and a surface which is part of the second pair  82   b , a threshold being formed between these two surfaces. In order to promote the passage of the support of the ring between the first pair and the second, the threshold is not at a right angle, but rather is tilted. 
         [0057]    Guide organs can be provided in order to optimize the translation of the lever  82 . The surfaces of the lever are thus perfectly positioned in relation to the ring  80 . 
         [0058]    Thus, depending on the position of the lever  82  chosen by the user, the rubbing organs  76 , mounted on the arms  74 , have a more or less large distance to travel before coming into contact with the inner wall  80   a  of the ring  80 . The movements of the arms  74 , at a given angular speed, are determined by their masses, the elastic characteristics of the springs  78 , the mass of the rubbing organs  76  and their positioning in relation to the pivot center. The obvious result of this is that the angular speed necessary for the rubbing organs to come into contact with the ring varies according to the parameters cited above. Adjusting the pre-winding of the springs  78  makes it possible, for example, to adjust the average duration of the ringing, and changing the distance to be traveled by the rubbing organs  76  makes it possible to go from slow speed to high speed. 
         [0059]    One will note that additional positions can be provided, in order to offer more adjustments of the frequency. The ring could also be moved by first and second surfaces arranged in different planes in reference to the ring and only acting on one zone of the ring. The surfaces therefore would not be arranged in pairs. The pins  84  provided for vertical guiding of the ring ensure that the latter part translates without putting itself at an angle. The lever can also have slanted planes such that the position of the ring can be adjusted continuously. The lever surfaces could also not comprise Moreover, other solutions can be considered by one skilled in the art to modify the relative level of the ring and of the rubbing organs. For example, the ring could be raised via a screw, also offering the possibility of continuously varying the frequency of the ringing. The plate could also be moved, even if such a solution is less simple a priori, in order to preserve the kinematic connection with the ringing gear. 
         [0060]    Thus are proposed embodiments making it possible to vary the speed of a watch ringing mechanism. Of course, the description above was provided solely as a non-limiting example of the invention and one skilled in the art will be able to provide for various variations without going beyond the scope of the invention, particularly concerning the speed or gear ratios. In the second embodiment, the bearing surfaces for the balls can also not be perfectly conical, but have a certain concavity or convexity.

Technology Category: g