CLOCK COMPRISING A DISPLAY ELEMENT FOR A LOCAL TIME (HT) AND A DISPLAY ELEMENT FOR A GMT TIME (GREENWICH MEAN TIME)

Description

Technical field

[0001] The present invention relates to a timepiece comprising a driving member, at least a first display member arranged to display a local time HT, a second display member arranged to be able to display a GMT time of a time zone different from that of the local time HT, a drive wheel set of the first display member arranged to be kinematically connected to the driving member in a disengageable manner, a first correction mechanism arranged to be able to be kinematically connected to the drive wheel set to allow the simultaneous correction of the local time HT and the GMT time, a second correction mechanism of the second display member, distinct from the first correction mechanism, and arranged to be able to correct the GMT time independently of the local time HT,a drive mechanism for the second display member comprising a differential gear comprising at least a first input arranged to be kinematically linked to the drive wheel of the first display member, a second input arranged to be kinematically linked to the second correction mechanism of the second display member, and an output arranged to drive said second display member., State of the art

[0002] Such a timepiece is for example described in document EP 3252543 or in document EP 2663902. In this timepiece, the simultaneous correction of the local time HT and the GMT time is carried out by means of the time-setting stem, i.e. the traditional winding stem, and the correction of the GMT time independently of the local time HT is carried out by means of a pusher. These different corrections are made possible by the use of a differential gear whose output is arranged to drive the second GMT time display member. However, the use of such a differential gear, due to the guides and gear ratios of its various components, causes a certain amount of play in the GMT time display train as well as in the GMT time correction train. This play is even more present in the case of bidirectional correction.

[0003] As a result, there is a risk that the GMT time display organ, once corrected, alone or with the HT time, will not reposition itself correctly, and more particularly in the case of bidirectional correction, so that it will no longer be synchronized with the positioning of the HT time display organ, in relation to the minutes.

[0004] Furthermore, in document EP 2663902, provision is made to correct the HT time by rotating the winding stem while keeping the pusher pressed. The disadvantage of this mechanism is that, once the HT time has been corrected, the minute display member moves at the same time as the HT time display member, there is a risk that the minute display member will not reposition itself correctly, so that the GMT time display member will no longer be synchronized with the corrected minute display member.

[0005] The present invention aims to remedy these drawbacks by proposing a timepiece making it possible to correct the HT time and / or the GMT time with a reduction in the play in the gears displaying the GMT time and correcting the GMT time, allowing a correction, in particular bidirectional, without risk of desynchronization of the GMT time display organ.

[0006] Another objective of the present invention is to propose a timepiece making it possible to correct the HT time display organ without risk of desynchronization of the GMT time display organ. Disclosure of the invention

[0007] To this end, the invention relates to a timepiece comprising a driving member, at least a first display member arranged to display a local time HT, a second display member arranged to be able to display a GMT time of a time zone different from that of the local time HT, a drive wheel of the first display member arranged to be kinematically connected to the driving member in a disengageable manner, a first correction mechanism arranged to be able to be kinematically connected to the drive wheel of the first display member to allow the simultaneous correction of the local time HT and the GMT time, a second correction mechanism of the second display member, separate from the first correction mechanism, and arranged to be able to correct the GMT time independently of the local time HT,a drive mechanism for the second display member comprising a differential gear comprising at least a first input arranged to be kinematically linked to the drive wheel of the first display member, a second input arranged to be kinematically linked to the second correction mechanism of the second display member, and an output arranged to drive said second display member.,

[0008] According to the invention, said timepiece comprises a gear train mounted in parallel to the drive mechanism of the second display member and arranged to be kinematically connected to the drive wheel of the first display member and to be kinematically connected to the output of the differential gear in a disengageable manner by means of a first star connected to said gear train mounted in parallel and a first jumper connected to the output of the differential gear and cooperating with said first star so that said output is driven by said gear train mounted in parallel during a simultaneous correction of the local time HT and the GMT time by the first correction mechanism and so that said output is uncoupled from said gear train mounted in parallel during a correction of the GMT time independently of the local time HT by the second correction mechanism while allowing, after correction,a repositioning of the second display member synchronized with the positioning of the first display member.,

[0009] The parallel-mounted gear train connected to the output of the differential gear train by means of a star / jumper system advantageously reduces the play in the GMT time display and GMT time correction gear trains and ensures correct repositioning of the GMT time display member after correction. Thus, the positioning of the GMT time display member remains permanently synchronized with the positioning of the HT time display member, relative to the minutes, even after simultaneous correction of the HT local time and GMT time or correction of GMT time alone.

[0010] Advantageously, the timepiece comprises a third local time correction mechanism HT distinct from the first and second correction mechanisms and arranged to be able to cooperate with the first local time display member HT in order to be able to drive only said first local time display member HT, step by step, during a correction of the local time HT. There is therefore no risk of desynchronization of the first local time display member HT from the minute display member during a correction of the local time HT.

[0011] Thus, the positioning of the GMT time display organ remains synchronized with the positioning of the local HT time and minute display organ, even after a correction of the local HT time alone, the minutes remaining fixed during this correction. Brief description of the drawings

[0012] Other characteristics and advantages of the present invention will appear on reading the following detailed description of an embodiment of the invention, given by way of non-limiting example, and made with reference to the appended drawings in which: there figure 1 is a simplified schematic diagram of the various mechanisms cooperating with the display organs of a timepiece according to the invention; the figure 2 is a plan view, dial side, of different mechanisms used in a timepiece according to the invention; the figure 3 is an isometric view, dial side, of the differential gear, the drive wheel of the first display member and the first correction mechanism; figure 4 is an isometric sectional view of the differential gear and the additional wheel; the Figure 5is an isometric view, dial side, of the parallel-mounted gear train and its star / jumper system, of the drive wheel of the first display organ and of the first correction mechanism; figure 6 is an isometric view, bottom side, of the differential gear and the star / jumper system, the additional wheel has been removed; the figure 7 is an isometric view, dial side, of the location display device, the differential gear and the second correction mechanism; the figure 8 is a plan view, dial side, of the third correction mechanism; and the figure 9 is a view of a display device arranged to display the difference between local time HT and GMT time and cooperating with the differential gear, used in a variant of the invention. Embodiments of the invention

[0013] There figure 1schematically represents a timepiece 1 according to the invention, comprising a driving member 2, such as a barrel, kinematically linked to a regulating member 4, such as a sprung balance. It is obvious that any other suitable driving member and regulating member can be used.

[0014] The timepiece 1 also comprises at least one first display member 6, such as a hand, arranged to display a local time HT, in cooperation with a minute display member (not shown).

[0015] The timepiece 1 also comprises a second display member 8, such as a hand, arranged to be able to display a GMT time of a time zone different from that of the local time HT.

[0016] It is obvious that any other suitable organ for displaying local time HT and GMT time can be used.

[0017] The timepiece also comprises a drive wheel 10 of the first display member 6 arranged to be kinematically linked to the motor member 2 in a disengageable manner.

[0018] In an advantageous manner, and with reference to the figures 3 And 5, the drive wheel 10 comprises an hour wheel or cannon wheel 12 arranged to drive the first display member 6 of the local time HT. The hour wheel 12 is carried in a known manner by the cannon pinion 14 which integrally carries the minute display member (such as a hand, not shown), and which is kinematically linked to the driving member 2 in a disengageable manner, for example by means of a friction 16. During normal operation of the timepiece, the cannon pinion 14 is driven via the driving member 2 and in turn drives the hour wheel 12. For this purpose, the cannon pinion 14 is arranged to cooperate with the minute wheel 18 and the hour wheel 12 is arranged to cooperate with the minute pinion 20, integral with the minute wheel 18, in a conventional manner.

[0019] The drive wheel 10 also comprises a drive pinion 21, integral with the hour wheel 12, and kinematically linked to a first input of a differential gear 22 which will be described in more detail below.

[0020] The timepiece 1 also comprises a first correction mechanism 23 arranged to be able to be kinematically linked to the drive wheel 10 of the first display member 6 of the local time HT to allow the simultaneous correction of the local time HT and the GMT time, preferably in a bidirectional manner. For this purpose, the hour wheel 12 is arranged to cooperate with the first correction mechanism 23.

[0021] More particularly, and with reference to the figures 2 , 3 And 5, the first correction mechanism 23 advantageously comprises a time-setting stem 24 arranged to be able to drive, preferably bidirectionally, the drive wheel 10 of the first display member 6 during the simultaneous correction of the local time HT and the GMT time. For this purpose, and in a standard manner, the time-setting stem 24 is the winding stem arranged to be able to occupy different successive distinct axial positions, and in particular a time-setting position allowing the simultaneous correction of the local time HT and the GMT time. In a standard manner, there is provided on the time-setting stem 24 a sliding pinion 26 slidably mounted on the stem 24 to be able to mesh with a first intermediate wheel 28, mounted freely in rotation on the frame of the part, when the time-setting stem 24 is in its time-setting position.Other gears 30 are provided between the first gear 28 and the minute wheel 18 to drive the cannon pinion 14 and the hour wheel 12 via the minute pinion 20 to set the time by rotating the stem 24.

[0022] This correction / time setting mechanism is known to those skilled in the art and does not require a more detailed description.

[0023] The rotation, preferably bidirectional, of the rod 24 causes the movement, preferably bidirectional, of the minute display member and the first display member 6 of the local time HT, but also the movement, preferably bidirectional, of the second display member 8 of the GMT time, as will be described below, for the simultaneous time setting / correction of the local time HT and the GMT time.

[0024] It is obvious that the winding stem 24 can be replaced by any other suitable correction stem.

[0025] The timepiece 1 also comprises a second correction mechanism 32 of the second display member 8, distinct from the first correction mechanism, and arranged to be able to correct the GMT time independently of the local time HT.

[0026] The second correction mechanism 32 will be described in more detail below.

[0027] The timepiece 1 also comprises a drive mechanism 34 of the second display member 8 comprising the differential gear 22.

[0028] With particular reference to the figure 4, said differential gear 22 comprises a first sun wheel 38 constituting the first input arranged to be kinematically linked to the drive wheel 10 of the first display member 6 of the local time HT by means of its external toothing which meshes with the drive pinion 21. The first sun wheel 38 is mounted freely in rotation on an axis 40 pivotally mounted on the frame of the part and which constitutes the output of the differential gear 22, arranged to drive the second display member 8. For this purpose, the axis 40 can directly carry said second display member 8 in a fixed manner or can comprise a return arranged to cooperate with said second display member 8.

[0029] The axle 40 integrally carries a sun gear 42.

[0030] The differential gear 22 also comprises a second planet wheel 44 constituting the second input arranged to be kinematically linked to the second correction mechanism 32 of the second display member 8.

[0031] The planet wheel 44 is mounted to rotate freely coaxially with the axis 40 and the sun wheel 38. It carries at least one planet pinion 46, here two planet pinions 46 arranged symmetrically with respect to the axis 40 and mounted to rotate freely on the planet wheel 44. Each planet pinion 46 is arranged to mesh both with the internal teeth of the sun wheel 38 and with the sun pinion 42.

[0032] In a known manner, the arrangement of the differential gear 22 allows, by the first input, the driving, by the motor member 2, of the first display member 6 of the local time HT, with the display member of the minutes, and of the second display member 8 of the GMT time, as well as the simultaneous correction by the first correction mechanism 23 of the first display member 6 of the local time HT, with the display member of the minutes, and of the second display member 8 of the GMT time, and by the second input, the correction of the second member 8 of the GMT time independently of the first display member 6 of the local time HT.

[0033] According to the present invention, the timepiece 1 comprises a gear train 48 mounted in parallel to the drive mechanism 34 of the second display member 8 and arranged to be kinematically connected to the drive wheel set 10 of the first display member 6 and to be kinematically connected to the output of the differential gear 22 in a disengageable manner by means of a first star 50 connected to said parallel-mounted gear train 48 and a first jumper 52 connected to the output of the differential gear 22 and cooperating with said first star 50 so that said output is driven by said parallel-mounted gear train 48 during a simultaneous correction of the local time HT and the GMT time by the first correction mechanism 23 and so that said output is uncoupled from said parallel-mounted gear train 48, in order to allow the disengagement of said output,during a correction of the GMT time independently of the local time HT by the second correction mechanism 32, while allowing, after one or other of the corrections, a repositioning of the second display member 8 synchronized with the positioning of the first display member 6.,

[0034] Advantageously, the parallel-mounted gear 48 comprises an additional wheel 54 mounted to rotate freely coaxially with the axis 40 of the differential gear 22, as shown by the figure 4 Advantageously, the additional wheel 54 has a barrel 54a in which the axle 40 rotates, ensuring better maintenance of said axle.

[0035] The additional wheel 54 is arranged to be kinematically connected to the drive wheel 10 of the first display member 6, and more particularly to the hour wheel 12 which is arranged to cooperate with said parallel-mounted gear train 48. For this purpose, a return wheel 56 is provided consisting of two stepped pinions 56a, 56b, integral with one another, the pinion 56a being arranged to cooperate with the hour wheel 12 of the drive wheel 10 and the pinion 56b being arranged to cooperate with the additional wheel 54 of the parallel-mounted gear train 48, as shown in Figure 5 .

[0036] In reference to the figure 4, the additional wheel 54 carries, in a fixed manner, the first star 50. As for the first jumper 52, it is mounted on board a board 58 coaxial with the additional wheel 54 and fixed to the axis 40 constituting the output of the differential gear 22. More particularly, the first jumper 52 comprises a first end 52a pivotally mounted on the board 58, its pivot axis being mounted fixedly on the board 58, said first end 52a cooperating with the first star 50, and a second end 52b mounted fixedly on said board 58, as shown by the figure 6 , in which the additional wheel is not shown.

[0037] Thus, the first jumper 52 is arranged to connect the additional wheel 54 to the output of the differential gear 22, in a disengageable manner by means of the star 50, so that said output is uncoupled from said additional wheel 54 during a correction of the GMT time independently of the local time HT by the second correction mechanism 32.

[0038] Advantageously, the parallel-mounted gear train 48 is arranged to be able to drive the output of the differential gear 22 at the same speed as the first input of the differential gear 22 drives said output, when said gear train 48 and the output are coupled or engaged by the star 50 / jumper 52 connection, that is to say during the driving by the motor member 2 of the first display member 6 of the local time HT and the second display member 8 of the GMT time as well as during the simultaneous correction by the first correction mechanism 23 of the first display member 6 of the local time HT and the second display member 8 of the GMT time.

[0039] In an advantageous manner, and with reference to the figures 2 And 7, the second correction mechanism 32 comprises in particular a correction gear train 60 cooperating with the planet carrier wheel 44 constituting the second input of the differential gear 22. In a particularly advantageous manner, said correction gear train is arranged to allow a correction preferably by steps of the second display member 8 of the GMT time, independently of the local time HT, that is to say independently of the first display member 6 of the local time HT and of the minute display member.

[0040] In the variant shown on the figures 2 to 8 , the timepiece comprises a first display device 61 arranged to display locations linked to the different time zones. Advantageously, said first location display device 61 is of the roller display device type arranged to display cities representative of the different time zones.

[0041] For example, said first location display device 61 comprises a main drum 62 carrying between its two cheeks 62a, 62b, eight triangular prismatic elements 63 mounted free to rotate about their respective longitudinal axes. On each of their three faces of each element 63 is inscribed a location corresponding to a time zone in order to be able to display, with the set of eight elements 63, the 24 time zones. Each prismatic element 63 carries at one end a toothed wheel 63a arranged to cooperate with a fixed finger (not shown) so as to advance each element 63 by 1 / 3 of a turn for one rotation of the main drum 62. Three rotations of the main drum 63 are therefore necessary to display the 24 cities corresponding to the 24 time zones. The cities are distributed on the different faces of the elements 63 so that they are displayed in the order of the time zones.

[0042] As shown by the figures 2 And 7 , the first display device 61 is provided on the kinematic chain between the second correction mechanism 32 and the planet wheel 44 constituting the second input of the differential gear 22 to allow a correction of the location displayed by the first display device 61 during a correction of the second display member 8 of the GMT time linked to said location by means of the second correction mechanism 32, independently of the local time HT.

[0043] Advantageously, the second correction mechanism 32 is arranged to perform a correction in steps. For this purpose, the second correction mechanism 32 comprises for example two correctors such as pushers (not shown) arranged to be actuated by a user in order to actuate respectively in one direction or another a two-arm control 64 cooperating with an eight-pointed star 66, mounted integrally on one of the ends of the shaft 67 of the main drum 62. The control 64 is arranged to advance the star 66 by one step in one direction or another, depending on the corrector used. Thus, with each correction on demand by pressing on a corrector, the star 66 advances by 1 / 8 of a turn driving the main drum 63 by 1 / 8 of a turn to display a face of the next element 63, while the element 63 which passes in front of the fixed finger advances by 1 / 3 of a turn.The correction is continued until the face of element 63 corresponding to the selected city appears.

[0044] The correction gear train 60 of the second correction mechanism 32 comprises a first wheel 68 secured to the shaft 67 of the main drum 62, a second wheel 70 meshing on the one hand with the first wheel 68 and on the other hand with different return wheels 72 mounted on the frame, the last of which meshes with the planet carrier wheel 44.

[0045] It is obvious that the pusher could be replaced by a correction rod arranged to have a preferably controlled rotation angle in order to control the rotation angle of the planet wheel 44 and therefore of the second display member 8 during its correction alone.

[0046] The bidirectional correction obtained with two correctors to actuate the control 64 advantageously makes it possible to correct the location and the second display member 8 in one direction or another.

[0047] It is of course possible to use only one corrector so that the correction will then be unidirectional.

[0048] In a variant of the invention, the first display device 61 of the cities representative of the different time zones can be replaced by a second display device 74 as shown in the figure 9 , arranged to directly and immediately display the difference between the local time HT, displayed by the first display member 6, and the GMT time, displayed by the second display member 8.

[0049] The second display device 74 comprises a fixed dial 75 graduated from 0 to 24, an indicator 76 mounted fixedly on the dial 75, for example in the form of a fixed circular sector positioned around the 0 used to define the local time HT as a reference (HT=0), as well as a third display member 78, such as a hand, mounted so as to be able to rotate relative to the dial 75. The position of the third display member 78 on the dial 75 relative to the fixed indicator 76 indicates the difference or the time difference value between the local time HT (0) and the chosen GMT time, for example a difference of +10h between the GMT time and the local time HT, as shown here in the figure 9 .

[0050] Thus the second display device 74 makes it possible to directly indicate to the user the difference from 0h to 24h between two time zones among the 24 possible time zones.

[0051] According to another variant not shown, the fixed dial 75 can be graduated, not from 0 to 24, but from 0 to -12 on one side of the 0 indicated by the fixed indicator 76 and from 0 to +12 on the other side of the 0, making it possible to directly indicate to the user the time difference from 0h to 12h in one direction or the other by means of the third display member 78.

[0052] As for the first display device, the second display device 74 is provided on the kinematic chain between the second correction mechanism 32 and the planet wheel 44 constituting the second input of the differential gear 22 to allow a correction of the difference between the local time HT and the GMT time displayed by the third display member 78, during a correction of the second display member 8 of the GMT time by means of the second correction mechanism 32, independently of the local time HT.

[0053] For this purpose, the third display member 78 is kinematically linked to the second correction mechanism 32 and to the second input of the differential gear 22. More specifically, the second correction mechanism 32 comprises a control arranged to rotate the third display member 78 in one direction or another depending on the time difference to be displayed, and a correction gear train kinematically linking the third display member 78 to the second input of the differential gear 22, said correction gear train comprising a first wheel meshing with the third display member 78 and a last wheel meshing with the planet carrier wheel 44, like the correction gear train 60.

[0054] It is obvious that the first location display device 61 or the second time difference display device 74 may not be present. In this case, the second correction mechanism 32 is arranged so that the cooperation between the corrector and the planet wheel 44 is done solely via the correction gear train 60.

[0055] Advantageously, the timepiece 1 comprises a third correction mechanism 90 of the first display member 6 of the local time HT distinct from the first and second correction mechanisms and arranged to be able to cooperate with said first display member 6 of the local time HT in order to be able to drive only said first display member 6 of the local time HT during a correction of the local time HT, that is to say without the minute display member, the first display member 6 then being uncoupled from the rest of the drive wheel set 10 and from the drive mechanism 34 of the second display member 8 of the GMT time.

[0056] Preferably, the third correction mechanism 90 is arranged to carry out a step-by-step correction of the first display member 6 alone, in order to guarantee, after its correction, a synchronized repositioning with the minute display member and with the second display member 8.

[0057] To this end, and with reference to the figures 2 And 8 , the third correction mechanism 90 of the first display member 6 comprises a saw-toothed correction wheel 92 mounted to rotate on the barrel of the hour wheel 12 and integrally carrying the first display member 6. The correction wheel 92 is connected to the hour wheel 12 in a disengageable manner.

[0058] The third correction mechanism 90 of the first display member 6 also comprises a correcting finger 94, actuable by a user, and arranged to actuate the correction wheel 92 by disengaging it from the rest of the drive wheel set 10, so as to drive only the first display member 6 for a correction by steps, independently of the minute display member and the second display member 8.

[0059] More particularly, the hour wheel 12 carries a second star 96 integrally, and the correction wheel 92 carries integrally a second jumper 98 cooperating with said second star 94 and arranged to connect the hour wheel 12 to said correction wheel 92 in a disengageable manner. Thus, said correction wheel 92 is uncoupled from said hour wheel 12 during a correction of the first display member 6 of the local time HT by the correcting finger 94, so that only the first display member 6 is moved for its correction.

[0060] The operation of the various mechanisms during normal operation of the timepiece is as follows: the driving member 2 drives the cannon pinion 14 which in turn drives the minute display member as well as the hour wheel 12, via the minute wheel 18 and the minute pinion 20. The hour wheel 12 drives the first display member 6 of the local time HT via the correction wheel 92 coupled to the hour wheel 12 by the star 96 / jumper 98 assembly.

[0061] The drive pinion 21 secured to the hour wheel 12 is also driven and in turn drives the sun wheel 38 of the differential gear 22. The planet wheel 44 being blocked by the first location display device 61, the star 66 being held by its jumper 69, the planet pinions 46 constitute simple return gears. The sun wheel 38 meshes with the planet pinions 46 which mesh with the sun pinion 42 so as to drive the axle 40, the rotation of the axle 40 causing the rotation of the second display member 8 to display the GMT time, without driving the main drum 62.

[0062] In parallel, the hour wheel 12 meshes with the pinion 56a, and therefore the pinion 56b of the intermediate wheel 56, said pinion 56b meshing with the additional wheel 54 of the parallel-mounted gear train 48. The latter is coupled to the axle 40 via the star 50 / jumper 52 assembly so that the axle 40 is also driven by the additional wheel 54, at the same speed as the drive speed via the sun wheel 38.

[0063] The parallel-mounted gear train 48 makes it possible to reduce the play due to the differential gear 22 solely to the play linked to said parallel-mounted gear train 48. The play of such a gear train, simply comprising the intermediate wheel 56 linked to the additional wheel 54, is much less than the play linked to the differential gear 22. In addition, the holding of the axle 40 is reinforced due to the connection to the additional wheel 54 via the star 50 / jumper 52 assembly. Thus, during normal operation of the part, the position of the second display member 8 of the GMT time remains perfectly synchronized with the position of the first display member 6 of the local time HT relative to the position of the minute display member, the play of the parallel-mounted gear train which comes into account between the local time HT and the GMT time being greatly reduced.

[0064] The dimensions and number of teeth of the various gears are chosen to have a 24-hour GMT time display, for example. It is obvious that the GMT time display can also be 12-hour, the dimensions and number of teeth of the various gears being adapted accordingly.

[0065] When simultaneously correcting the local time HT and the GMT time, the user operates the winding stem 24 moved into its time-setting position in order to engage the sliding pinion 26 with the first intermediate wheel 28. The cannon-pinion is uncoupled from the driving member 2 by friction 16. When the stem 24 rotates, the first intermediate wheel 28 driven by the sliding pinion 26 drives the other intermediate wheels 30, then the minute wheel 18 and the minute pinion, which in turn drive the cannon-pinion and the hour wheel 12 respectively to set the local time HT, by moving the display members for the hour HT and the minutes.As described above, the drive pinion 21 secured to the hour wheel 12 meshes with the sun wheel 38 of the differential gear 22 and in parallel the hour wheel 12 meshes with the parallel-mounted gear train 48 so as to drive the rotation of the axis 40 and therefore the rotation of the second display member 8 for its correction, without driving the main drum 62. As described above, the play generated by the parallel-mounted gear train 48 is much less than the play generated by the differential gear 22. In addition, the use of the stem 24 allows a bidirectional correction of the HT time and the GMT time.Thus, during a simultaneous and bidirectional time setting or correction of the local time HT and the GMT time, the position of the second display member 8 of the GMT time remains perfectly synchronized with the position of the first display member 6 of the local time HT relative to the position of the minute display member, the play of the gear train mounted in parallel which comes into account between the local time HT and the GMT time being greatly reduced.

[0066] When correcting the GMT time and the location, when the first location display device 61 is present, the user actuates one of the correctors of the second correction mechanism 32 by successive pressures in order to actuate the main drum 62 and its elements 63 until the desired location is displayed. In parallel, the correction gear train 60 is driven so as to drive the planet wheel 44 of the differential gear 22. Due to the differential gear used, it is considered that the sun wheel 38 is stationary relative to the correction speed, so that the satellite pinions 46, carried by the planet wheel 44, on the one hand slide on the internal teeth of the sun wheel 38 and on the other hand drive the axis 40, and therefore the second display member 8, by meshing with the sun pinion 42.It is also considered that the additional wheel 54 is stationary relative to the correction speed, so that the axis 40 disconnects from the additional wheel 54, the jumper 52 no longer cooperating with the star 50, and skipping a tooth of the star 50.

[0067] The elements 63 of the main drum 62 and the second GMT time display member are corrected simultaneously, independently of the first local time HT display member 6 and the minute display member, due to the differential gear 22, the star 50 / jumper 52 assembly linked to the axis 40 of said differential gear 22 allowing said axis 40 to reposition itself precisely relative to the position of the first display member 6 after each correction of the second GMT time display member 8, the jumper 52 jumping a tooth of the star 50 to reposition itself precisely between the following teeth, so that the position of said second GMT time display member 8 remains perfectly synchronized with the position of the first local time HT display member 6 relative to the position of the minute display member.

[0068] In addition, the use of a step corrector makes it possible to precisely control the rotation angles of the various gears when correcting the GMT time and the location so as to increase the precision of the repositioning of the axis 40 and therefore of the second display member 8 of the GMT time after its correction.

[0069] Similarly, when correcting the difference between the local time HT and the GMT time when the second display device 74 is present, resulting in a correction of the GMT time alone, the user actuates the second correction mechanism 32 in order to move the third display member 78 until the desired time difference is displayed on the dial 75. In parallel, the correction gear train of the second correction mechanism 32 is driven so as to drive the planet wheel 44 of the differential gear 22, driving the axle 40, and therefore the second GMT time display member 8.As described above, the third display member 78 and the second GMT time display member 8 are corrected simultaneously, independently of the first local time HT display member 6 and the minute display member, due to the differential gear 22, the star 50 / jumper 52 assembly linked to the axis 40 of said differential gear 22 allowing the axis 40 to reposition itself precisely relative to the position of the first display member 6 after each correction of the third display member 78 of the difference between the local time HT and the GMT time and of the second GMT time display member 8.

[0070] When correcting the first display member 6 of the HT time alone, for example during a first adjustment after purchasing the watch or when changing from summer time to winter time (which can be done on different dates depending on the time zones), the user actuates the correcting finger 94 so as to disconnect the correction wheel 92 from the rest of the drive wheel set 10, the jumper 98 no longer cooperating with the star 96. The step-by-step correction of the correction wheel 92 secured to the first display member 6 makes it possible to advance only said first display member 6 in steps of 1 hour, without driving the minute display member, nor the second display member 8 of the GMT time. Thus the position of the first display member 6 of the local time HT remains perfectly synchronized with the position of the second display member 8 of the time GMT relative to the position of the minute display member.

[0071] Thus, the timepiece according to the invention allows simultaneous correction of the locations and the GMT time without correcting the local time HT, the simultaneous and bidirectional time setting or correction of the local time HT and the GMT time without correcting the displayed location, and the correction of the display member 6 of the local time HT only, making it possible, after one or other of these corrections, to guarantee a positioning of the second GMT time display member permanently synchronized with the positioning of the first display member HT relative to the position of the minute display member.

Claims

1. A timepiece (1) including a motor organ (2), at least one first display member (6) arranged to display a local time HT, a second display member (8) arranged to be able to display a GMT time of a different time zone from that of the local time HT, a drive wheel and pinion (10) of the first display member (6) arranged to be kinematically linked to the motor organ (2) in a disengageable manner, a first correction mechanism (23) arranged to be able to be kinematically linked to the drive wheel and pinion (10) of the first display member (6) to allow simultaneous correction of the local time HT and the GMT time, a second correction mechanism (32) of the second display member (8), distinct from the first correction mechanism (23), and arranged to be able to correct the GMT time independently of the local time HT, a drive mechanism (34) of the second display member (8) including a differential gear (22) comprising at least one first input arranged to be kinematically linked to the drive wheel and pinion (10) of the first display member (6), a second input arranged to be kinematically linked to the second correction mechanism (32) of the second display member (8), and an output arranged to drive said second display member (8), characterized in that it includes a geartrain (48) mounted in parallel with the drive mechanism (34) of the second display member (8) and arranged to be kinematically linked to the drive wheel and pinion (10) of the first display member (6) and to be kinematically linked to the output of the differential gear (22) in a disengageable manner by means of a first star (50) linked to said geartrain mounted in parallel (48) and of a first jumper (52) connected to the output of the differential gear (22) and cooperating with said first star (50) such that said output is driven by said geartrain mounted in parallel (48) during a simultaneous correction of the local time HT and the GMT time by the first correction mechanism (23) and such that said output is uncoupled from said geartrain mounted in parallel (48) during a correction of the GMT time independently of the local time HT by the second correction mechanism (32) while allowing, after correction, a repositioning of the second display member (8) synchronized with the positioning of the first display member (6).

2. The timepiece according to Claim 1, characterized in that said geartrain mounted in parallel (48) includes an additional wheel (54) mounted freely in rotation coaxially with the differential gear (22) and arranged to be kinematically linked to the drive wheel and pinion (10) of the first display member (6), said additional wheel (54) carrying said first star (50), and said first jumper (52) being arranged to connect said additional wheel (54) to the output of the differential gear (22) such that said output is uncoupled from said additional wheel (54) during a correction of the GMT time independently of the local time HT by the second correction mechanism (32).

3. The timepiece according to Claim 2, characterized in that said first jumper (52) includes a first end (52a) pivotably mounted on a plate (58) which is coaxial with the additional wheel (54) and integral with the output of the differential gear (22), said first end (52a) cooperating with the first star (50), and a second end (52b) which is integral with said plate (58).

4. The timepiece according to any one of the preceding claims, characterized in that said geartrain mounted in parallel (48) is arranged to be able to drive the output of the differential gear (22), when they are coupled, at the same speed as the first input of the differential gear (22) drives said output.

5. The timepiece according to any one of the preceding claims, characterized in that the drive wheel and pinion (10) of the first display member (6) includes a hour wheel (12) arranged to be kinematically linked to the motor organ (2) in a disengageable manner and to drive the first display member (6), said hour wheel (12) being arranged to cooperate, on the one hand, with the first correction mechanism (23) and, on the other hand, with the geartrain mounted in parallel (48) and a drive pinion (21) kinematically linked to the first input of the differential gear (22).

6. The timepiece according to Claims 2 and 5, characterized in that it includes an intermediate wheel (56) arranged to cooperate, on the one hand, with the hour wheel (12) of the drive wheel and pinion (10) of the first display member (6) and, on the other hand, with the additional wheel (54) of the geartrain mounted in parallel (48).

7. The timepiece according to any one of the preceding claims, characterized in that the differential gear (22) includes a first sun wheel (38), constituting the first input, mounted freely in rotation on an axis (40), constituting the output of the differential gear (22), carrying a sun pinion (42), and a second planetary wheel carrier (44), constituting the second input, carrying at least one planetary pinion (46) meshing both with the first sun wheel (38) and with the sun pinion (42).

8. The timepiece according to any one of the preceding claims, characterized in that the first correction mechanism (23) includes a hand-setting stem (24) arranged to be able to drive the drive wheel and pinion (10) of the first display member (6) in a bidirectional manner during the simultaneous correction of the local time HT and the GMT time.

9. The timepiece according to any one of the preceding claims, characterized in that the second correction mechanism (32) includes a correction geartrain (60) cooperating with the second input of the differential gear (22) and arranged to allow a step-by-step correction of the second display member (8) independently of the local time HT.

10. The timepiece according to any one of the preceding claims, characterized in that it includes a first display device (61) arranged to display places linked to the different time zones, said first device for displaying places (61) being provided on the kinematic chain between the second correction mechanism (32) and the second input of the differential gear (22) in order to allow a correction of the place displayed during a correction of the second GMT time display member (8) linked to said place, independently of the local time HT, by the second correction mechanism (32).

11. The timepiece according to Claim 10, characterized in that the first device for displaying places (61) is a roller display device arranged to display cities.

12. The timepiece according to any one of the preceding claims, characterized in that it includes a second display device (74) arranged to display the difference between the local time HT and the GMT time, said second display device being provided on the kinematic chain between the second correction mechanism (32) and the second input of the differential gear (22) in order to allow a correction of the difference between the local time HT and the GMT time displayed during a correction of the second GMT time display member (8), independently of the local time HT, by the second correction mechanism (32).

13. The timepiece according to Claim 12, characterized in that the second display device (74) includes a dial (75), an indicator (76) which is mounted in a fixed manner on the dial (75) and arranged to define the local time HT as a reference point, and a third display member (78) mounted in a rotationally movable manner with respect to said dial (75), the position of the third display member (78) on the dial (75) with respect to the indicator (76) indicating the difference between the local time HT and the GMT time, said third display member (78) being kinematically linked to the second correction mechanism (32) and to the second input of the differential gear (22).

14. The timepiece according to any one of the preceding claims, characterized in that it includes a third correction mechanism (90) of the first display member (6) distinct from the first and second correction mechanisms (23, 32) and arranged to be able to cooperate with said first local time HT display member (6) in order to be able to solely drive said first local time HT display member (6) during a correction of the local time HT.

15. The timepiece according to Claims 5 and 14, characterized in that the third correction mechanism (90) of the first display member (6) includes a correction wheel (92) which is integral with the first display member (6) and linked to the hour wheel (12) in a disengageable manner, and a correcting finger (94) arranged to actuate said correction wheel (92) by disengaging it so as to solely drive the first display member (6) for a step-by-step correction.

16. The timepiece according to Claim 15, characterized in that the hour wheel (12) carries a second star (96) and in that the correction wheel (92) carries a second jumper (98) cooperating with said second star (96) and arranged to connect the hour wheel (12) to said correction wheel (92) such that said correction wheel (92) is uncoupled from said hour wheel (12) during a correction of the first display member (6) of the local time HT by the correcting finger (94).