Abstract:
An articulated watch includes two juxtaposed cases, each containing an electronic movement, and a connector for mechanically joining the two cases in an articulated manner and allowing the two movements to be connected using electrical conductors. The connector is formed of two bars that are arranged on either side of the cases. The bars include an internal channel for the passage of the electrical conductors and have ends that are mounted so as to rotate freely but are locked in translation in four holes arranged in the middle parts of the cases along two substantially parallel axes.

Description:
BACKGROUND OF THE INVENTION 
   The present invention concerns an articulated electronic watch, that includes two juxtaposed cases which are joined to each other in an articulated manner. 
   A watch of this type is disclosed in Swiss Patent No. 647 916. The back covers of the two cases are articulated to each other by means of simple hinges. Sandwiched between the back cover and middle part of each case is a sealing gasket connected to the gasket of the adjoining case, at the location of the articulation, by a neck made of the same material, the assembly thus forming a sealing gasket in one piece. Electric conductors are arranged inside the necks to connect the electronic components of the two cases to each other. 
   Such a solution enables the realisation of a watch which can occupy a relatively large surface area on the wearer&#39;s wrist, while matching the shape thereof. However, it has the drawback of requiring articulations occupying practically the entire width of the case. This results in a certain heaviness of appearance. Moreover, the effect procured by the presence of two movements in two separate cases is not used to advantage. 
   SUMMARY 
   The object of the present invention is to enable the realisation of a watch which includes several distinctly separate cases, but which has a particularly light appearance, allows numerous variants, can easily be adapted to the wearer&#39;s arm and allows sealing to be assured by simple means. 
   More precisely, the invention concerns an articulated watch of the type including:
         two juxtaposed cases, each containing an electronic movement and including a back cover, a middle part and a crystal, and   connecting means for mechanically joining the two cases in an articulated manner and allowing the two movements to be connected using electrical conductors.       

   This watch is characterised in that said connecting means are formed of two bars which are arranged on either side of the cases, which include an internal channel for the passage of the electrical conductors and whose ends are mounted so as to rotate freely but that are locked in translation in four holes arranged in the middle parts of the cases along two substantially parallel axes, there being two coaxial holes per case.  
   Advantageously, the ends of the bars are fitted with a sealing gasket disposed within a groove arranged in the portion thereof which passes through the hole of the middle part, while the ends of the channels which open into the cases are closed in a watertight manner. The channels can also be filled with an organic material in which the electrical conductors are embedded. 
   According to a preferred embodiment, the ends of each bar have an end portion projecting into the interior of the cases which includes a groove co-operating with a wedge in order to prevent any axial movement of the bar. Moreover, this end portion also includes means for limiting the rotational movement of the bar. 
   Each bar is advantageously formed of a hollow median portion and two end portions which are formed of a cylindrical tube fixed to the median portion. The median portion includes a base comprising two holes into which the tubes are fixed, walls substantially perpendicular to the base and a cap covering said walls. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other advantages and features of the invention will appear from the following description, which is made with reference to the annexed drawings, in which: 
       FIG. 1  shows an overall view of a watch according to the invention; 
       FIG. 2  shows, along a cross-section in the thickness of the watch of  FIG. 1 , a bar connecting the portions of the cases in which its ends are engaged; and 
       FIGS. 3 and 4  are partial enlarged views of  FIG. 2  respectively along the lines III—III and IV—IV. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Electronic watch  10  shown in  FIG. 1  includes two identical cases, an upper case  12 , and lower case  14 , substantially in the shape of a semi-circle, with a rounded portion  16  and a rectilinear portion  18 . They each contain an analogue quartz movement (not shown).  
   Rectilinear portions  18  of the two cases are parallel to each other but not in contact, so that there exists between them a gap  20 , which is sufficiently large, typically from 1 to 2 mm, to show clearly that there are two completely separate and independent cases. 
   Cases  12  and  14  are joined by two lateral bars  22  which are perpendicular to their rectilinear portions  18  and are fixed symmetrically in an articulated manner around two parallel axes A by each of their ends in four holes arranged in rounded portions  16 , there being two coaxial holes per case. In such a watch, it is very desirable for the link between the two cases to be articulated in such a way that it matches the shape of the wrist as well as possible. Bars  22  are also used to pass lead wires between the two cases assuring the electrical connection between their respective movements. They will be described in more detail with reference to  FIGS. 2 to 4 . 
   Cases  12  and  14  each include, in a conventional manner, a pair of horns  24  used respectively for attaching the two strands of a wristlet  26 . 
   Each case  12  and  14  has a crystal, not visible in the drawing, coated on the inside, in the portion thereof contiguous to rectilinear portion  18 , with a mask  28  the use of which will appear hereinafter. 
   Upper case  12  is fitted with a semi-dial  30  above which are situated an hour hand  32  and a minute hand  34 . Likewise, lower case  14  is fitted with a semi-dial  36  above which are situated an hour hand  38  and a minute hand  40 . Upper semi-dial  30  includes markings for the time display between 9 and 3 o&#39;clock, while lower semi-dial  36  includes markings for the time display between 3 and 9 o&#39;clock. Together, they thus constitute the normal dial of a watch. 
   Each of the analogue movements placed in the cases includes, for driving each hand, a motor and a gear train. One of them contains the electronic circuit driving the four motors in a co-ordinated manner, while the other contains the battery for the electric power supply of the whole. 
   Upper case  12  displays the hours comprised between 9 and 3 and the minutes comprised between 45 and 15, while lower case  14  displays the  hours comprised between 3 and 9 and the minutes comprised between 15 and 45. Thus, the watch of  FIG. 1  displays 9 o&#39;clock by means of hand  32  of upper case  12 , and 20 minutes by means of hand  40  of lower case  14 . Minute hand  34  and hour hand  38  are then hidden by masks  28 . 
   When a hand reaches the end of its travel, the electronic circuit rapidly causes it to move backwards, via a rotation slightly greater than 180°, into a standby position behind mask  28 . The hand of the other case then takes over. 
   A detailed description of the means implemented to perform the above functions is provided in the French Patent Application entitled &lt;&lt;WATCH WITH SECTOR DISPLAY&gt;&gt; filed by the Applicant on the same date as the present Application. 
   Reference will now be made to  FIGS. 2 to 4  which show the manner in which bars  22  assure not only the articulated mechanical connection between the two cases while preserving the sealing thereof, but also their electrical connection by providing passages for a plurality of lead wires  42 . 
   Cases  12  and  14  each include a back cover  44  and a middle part  46  which is perforated, along axis A, with a cylindrical channel accommodating a sleeve  48 . It is to be noted that sleeve  48  is not indispensable but in the absence thereof the accuracy of the mechanism is liable to be insufficient to assure sealing of the passage. 
   Bar  22  is formed of a median portion  22   a  perpendicular to axes A and two end portions  22   b  which are respectively coaxial to said axes. Median portion  22  includes a base  50  the ends of which have a recess occupying space on sleeves  48 , walls  52  perpendicular to base  50 , and a cap  54  covering walls  52  onto which it is bonded or welded. A channel  56  is thus formed between base  50  and cap  54 . 
   As  FIG. 3  shows in more detail, each end portion  22   b  
is formed of a cylindrical tube  58  driven in a water resistant manner by its end into a hole made in base  50 . Tube  58  is itself engaged in sleeve  48  inside which it is fitted as so to be able to  rotate freely. Tube  58  further includes in its median portion which passes through sleeve  48 , a first groove accommodating a sealing gasket  60  and at its other end situated inside the case second groove for locking a wedge  62  which allows the bar to be fixed in an articulated manner. 
   As can be seen more particularly in  FIG. 4 , tube  58  includes, between the inner face of sleeve  48  and wedge  62 , two diametrically opposite flat portions  64  which co-operate with an elongated plate  66  fitted with an oblong hole  68 . This plate is held in place by a washer  70  inserted between the plate and wedge  62 . In order to realise an articulation of limited amplitude, a groove  72  is made in the inner face of the middle part, in which plate  66  is engaged and whose width is substantially greater than that of said plate, which allows the bar to pivot over a certain amplitude. 
   As  FIG. 2  shows, lead wires  42  pass from one case to the other making use of channel  56 . They are distributed in the two bars  22 , one being used, for example, for supply conductors and the other for the control conductors. 
   Since the shape of cap  54  can, for reasons of aesthetic effect, be quite complex, it is difficult to assure a perfectly watertight connection of the system. It is also advantageous to close the holes of tubes  58 , for example by means of a drop of glue  74  arranged at the end of said holes within the case. In a variant, the bar can simply be filled with an organic material in which the electrical lead wires are embedded. 
   The structure of the bars which have just been described allows a high level of security to be assured as regards sealing, while providing great aesthetic variety. Indeed, one need only manufacture caps  54  which are different in shape or in the material selected, to considerably change the general appearance of the watch. Two colour timepieces can thus be made by using caps made of gold, the cost of which remains modest and which gives the watch a very elegant appearance. 
   As can be seen in  FIGS. 2 and 4 , the electrical connecting wires  42  can be simply welded onto printed circuits  76  included in the two movements. It would also be possible to fix sockets to the end of the wires, the latter then  being screwed onto the printed circuits. In another variant, the electrical connection could also be made by means of a flexible printed circuit. 
   In the example described, the watch includes analogue display means in both cases. It goes without saying that other variants could be envisaged without thereby departing from the scope of the present invention. It would thus be possible to place an analogue display in one case and a digital display in the other, controlled by a single same quartz, or even to arrange a power supply provided with a generator in one of the cases and a conventional electronic movement in the other.