A clock including a component for displaying local time (HT) and a component for displaying GMT time

Abstract

The invention relates to a timepiece 1 comprising a first member 6 for displaying local time HT, a second member 8 for displaying GMT time, a drive wheel 10 of the first display member 6, a first correction mechanism 23 adapted to be kinematically coupled to the drive wheel 10 of the first display member 6 to allow simultaneous correction of local time HT and GMT time, a second correction mechanism 32 of the second display member 8 adapted to be able to correct the GMT time independently of the local time HT, and a drive mechanism 34 of the second display member 8 including a differential gear 22 with a first input part adapted to be kinematically coupled to the drive wheel 10 of the first display member 6, a second input part adapted to be kinematically coupled to the second correction mechanism 32 of the second display member 8 and an output part adapted to drive said second display member 8. The timepiece comprises a gear train 48 mounted parallel to the drive mechanism 34 of the second display member 8, said gear train 48 being kinematically coupled in an engageable and disengageable manner to the drive wheel 10 of the first display member 6 and to the output part of the differential gear 22 by means of a first star 50 coupled to said parallel mounted gear train 48 and a first jumper 52 connected to the output part of the differential gear 22 and cooperating with said first star 50, so that during the simultaneous correction of the local time HT and the GMT time by the first correction mechanism 23, said output part is driven by said parallel mounted gear train 48, and during the correction of the GMT time independent of the local time HT by the second correction mechanism 32, said output part is decoupled from said parallel mounted gear train 48, while after the correction, a repositioning of the second display member 8 synchronized with the positioning of the first display member 6 is possible.

Description

[Technical field]

[0001] The invention relates to a timepiece comprising a motor engine, at least one first display member adapted to display local time HT, a second display member adapted to display GMT time in a time zone different from that of the local time HT, a drive wheel and pinion of the first display member adapted to be kinematically connected to the motor engine in an detachable manner, a first correction mechanism adapted to be kinematically connected to the drive wheel to allow simultaneous correction of the local time HT and the GMT time, a second correction mechanism of the second display member that is separate from the first correction mechanism and adapted to correct the GMT time independently of the local time HT, and a drive mechanism of the second display member including a differential gear with at least one first input part adapted to be kinematically connected to the drive wheel of the first display member, a second input part adapted to be kinematically connected to the second correction mechanism of the second display member and an output part adapted to drive the second display member mentioned above. [Background technology]

[0002] Such a watch is described, for example, in the document EP 2 663 902. In this watch, the local time HT and the GMT time are corrected simultaneously by means of a hand-turning stem, i.e. a traditional winding stem, and the GMT time is corrected independently of the local time HT by means of a push piece. These different corrections are made possible by the use of a differential gear, the output of which is adapted to drive a second GMT time display member. However, the use of such a differential gear causes some play in the GMT time display gear train and the GMT time correction gear train, due to the gear ratios of the various components of the guides and the differential gear. This play is even more present in the case of a bidirectional correction.

[0003] There is therefore a risk that the element for indicating GMT time will not correctly change position when corrected alone or together with HT time, and this is particularly so in the case of a bidirectional correction, with the result that the element for indicating GMT time is no longer synchronized, in terms of minutes, with the positioning of the element for indicating HT time.

[0004] In addition, in document EP 2 663 902, the HT time is corrected by rotating the winding stem by continuing to press the push piece. The disadvantage of this mechanism is that, given that the minute display element moves around simultaneously with the element for displaying the HT time, there is a risk that once the HT time is corrected, the minute display element will not change its position correctly, with the result that the element for displaying the GMT time will no longer be synchronized with the corrected minute display element. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] EP2663902 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to remedy these drawbacks by proposing a timepiece which reduces the play in the gear train for displaying GMT time and for correcting GMT time, making it possible to correct HT time and / or GMT time, a correction which is in particular bidirectional, without the risk of desynchronizing the components for displaying GMT time.

[0007] Another object of the invention is to propose a timepiece which makes it possible to correct the components for displaying HT time without the risk of desynchronization of the components for displaying GMT time. [Means for solving the problem]

[0008] To this end, the invention relates to a timepiece comprising a motor engine, at least one first display member adapted to display local time HT, a second display member adapted to display GMT time in a time zone different from that of the local time HT, a drive wheel of the first display member adapted to be kinematically connected to the motor engine in an engageable and detachable manner, a first correction mechanism adapted to be kinematically connected to the drive wheel of the first display member to allow simultaneous correction of the local time HT and the GMT time, a second correction mechanism of the second display member which is distinct from the first correction mechanism and adapted to be able to correct the GMT time independently of the local time HT, and a drive mechanism of the second display member including a differential gear with at least one first input part adapted to be kinematically connected to the drive wheel of the first display member, a second input part adapted to be kinematically connected to the second correction mechanism of the second display member and an output part adapted to drive said second display member.

[0009] According to the invention, said timepiece comprises a gear train mounted in parallel with the drive mechanism of the second display member, said gear train being kinematically coupled in an engageable and disengageable manner to the drive wheel of the first display member and to the output part of the differential gear by a first jumper connected to a first star and to the output part of the differential gear coupled to said parallel mounted gear train and cooperating with said first star, so that said output part is driven by said parallel mounted gear train during the simultaneous correction of local time HT and GMT time by the first correction mechanism, and said output part is decoupled from said parallel mounted gear train during the correction of GMT time independent of local time HT by the second correction mechanism, while after the correction, a repositioning of the second display member synchronized with the positioning of the first display member is possible.

[0010] A gear train mounted in parallel and connected to the output of the differential gear by a star / jumper system advantageously makes it possible to reduce play in the gear train for indicating GMT time and in the gear train for correcting GMT time, and to ensure a correct repositioning after correction of the member for indicating GMT time, so that the positioning of the member for indicating GMT time remains permanently synchronized, in terms of minutes, with the positioning of the member for indicating HT time, even after a simultaneous correction of local time HT and GMT time, or of GMT time alone.

[0011] The timepiece advantageously comprises a third local time HT correction mechanism, which is separate from the first and second correction mechanisms and is adapted to cooperate with said first local time HT display member in order to enable only the first local time HT display member to be driven bit by bit alone during the correction of the local time HT.Therefore, there is no risk of desynchronization of the first local time HT display member with the minute display member during the correction of the local time HT.

[0012] Thus, the positioning of the GMT hour display member remains synchronized with the positioning of the local time HT and minute display members even after correction of the local time HT alone, and the minutes remain fixed during correction of the local time HT alone.

[0013] Other characteristics and advantages of the invention will become apparent on reading the following detailed description of an embodiment of the invention given as a non-limiting example and on reference to the accompanying drawings, in which: [Brief description of the drawings]

[0014] [Figure 1] 2 is a simplified diagram of the various mechanisms cooperating with the display members of the timepiece according to the invention; [Diagram 2] FIG. 2 is a plan view, from the dial side, of the various mechanisms used in the timepiece according to the invention; [Diagram 3] FIG. 2 is an isometric view from the dial side of the differential gear, the drive wheel of the first display member, and the first corrector mechanism. [Figure 4] FIG. 2 is an isometric cross-sectional view of a differential gear and an additional vehicle. [Diagram 5] FIG. 1 is an isometric view from the dial side of the parallel-mounted gear train and its star / jumper system, the drive wheel of the first display element and the first correction mechanism. [Figure 6] Isometric view from the back of the differential and star / jumper system with additional cars removed. [Figure 7] FIG. 2 is an isometric view from the dial side of the device for indicating the location, the differential gear and the second correction mechanism. [Figure 8] FIG. 11 is a plan view of the third correction mechanism seen from the dial side. [Figure 9] FIG. 1 is a diagram of a display device used in a variant of the invention, for indicating the difference between local time HT and GMT time, and adapted to cooperate with a differential gear; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] 1 shows diagrammatically a timepiece 1 according to the invention, comprising a motor engine 2, such as a barrel, kinematically linked to a regulating member 4, such as a sprung balance. It is clear that any other suitable motor engine and any suitable regulating member can be used.

[0016] The timepiece 1 also includes at least one first display member 6, such as a hand adapted to display local time HT, cooperating with a minute display member (not shown).

[0017] The timepiece 1 also includes a second display member 8, such as a hand, adapted to be able to display GMT time in a time zone different from the time zone of the local time HT.

[0018] Obviously, any other suitable components for displaying local time HT and GMT time may be used.

[0019] The timepiece also includes a drive wheel 10 of the first display member 6 adapted to be kinematically coupled to the motor engine 2 in a disengageable manner.

[0020] Advantageously, and with reference to Figures 3 and 5, the drive wheel 10 comprises an hour wheel 12 adapted to drive the first local time HT display member 6. The hour wheel 12 is carried in a known manner by a cannon pinion 14, which carries in an integral manner a minute display member (hands, etc., not shown) and is kinematically connected to the motor engine 2 in an engageable manner, for example by friction 16. During normal operation of the timepiece, the cannon pinion 14 is driven via the motor engine 2, which in turn drives the hour wheel 12. For this purpose, the cannon pinion 14 is adapted to cooperate with a minute wheel 18, which in turn is adapted to cooperate with a minute-pinion 20, which is integral with the minute wheel 18 in a traditional manner.

[0021] The drive wheel 10 also includes a drive pinion 21 which is integral with the hour wheel 12 and is kinematically connected to a first input of a differential gear 22 which will be described in more detail below.

[0022] The timepiece 1 also comprises a first correction mechanism 23 adapted to be kinematically coupled to the drive wheel 10 of the first local time HT display member 6 in order to enable simultaneous correction of the local time HT and the GMT time, preferably in a bidirectional manner. For this purpose, the hour wheel 12 is adapted to cooperate with the first correction mechanism 23.

[0023] More specifically, and with reference to Figures 2, 3 and 5, the first correction mechanism 23 advantageously comprises a hand-driving stem 24 adapted to drive the drive wheel 10 of the first display member 6, preferably in a bidirectional manner, during the simultaneous correction of the local time HT and GMT. For this purpose, and in a standard manner, the hand-driving stem 24 is a winding stem adapted to occupy various successively separate axial positions, in particular hand-driving positions allowing the simultaneous correction of the local time HT and GMT. In a standard manner, a clutch wheel 26 is provided on the hand-driving stem 24, which is slidably mounted on the stem 24 so that when the hand-driving stem 24 is in its hand-driving position, it can mesh with a first intermediate wheel 28 rotatably mounted on the frame of the piece. In order to rotate the hands by rotating the stem 24, another intermediate wheel 30 is provided between the first intermediate wheel 28 and the minute wheel 18, and drives the cannon pinion 14 and the hour hand wheel 12 via the minute pinion 20.

[0024] This correction / needle turning mechanism is known to those skilled in the art and need not be described in further detail.

[0025] Rotation of the stem 24, which is preferably bidirectional, results in a preferably bidirectional movement of the minute display member and the first local time HT display member 6, but also a preferably bidirectional movement of the second GMT display member 8, as described below, for simultaneous hand turning / correction of local time HT and GMT time.

[0026] It is evident that the winding stem 24 may be replaced by any other suitable modified stem.

[0027] The watch 1 also includes a second corrector mechanism 32 of the second display member 8 which is separate from the first corrector mechanism and which is adapted to correct the GMT time independently of the local time HT.

[0028] The second modifying mechanism 32 is described in more detail below.

[0029] The timepiece 1 also comprises a drive mechanism 34 for the second display member 8 which includes the differential gear 22 .

[0030] 4, said differential gear 22 comprises a first sun gear 38 constituting a first input adapted to be kinematically linked to the drive wheel 10 of the first local time HT display member 6 through its external toothing meshing with the drive pinion 21. The first sun gear 38 is rotatably mounted on an axle 40 pivotally mounted on the frame of the piece, the axle 40 constituting an output of the differential gear 22 adapted to drive the second display member 8. For this purpose, the axle 40 can directly carry said second display member 8 in an integral manner or can comprise an intermediate wheel adapted to cooperate with said second display member 8.

[0031] The shaft 40 carries in an integral manner a sun pinion 42 .

[0032] The differential gear 22 also includes a second planetary gear carrier 44 constituting a second input adapted to be kinematically coupled to the second correcting mechanism 32 of the second indicating member 8 .

[0033] The planet gear carrier 44 is rotatably mounted coaxially with the shaft 40 and the sun gear 38. The planet gear carrier 44 carries at least one planet pinion 46, here having two planet pinions 46 arranged symmetrically about the shaft 40 and rotatably mounted on the planet gear carrier 44. Each planet pinion 46 is adapted to mesh with both the internal teeth of the sun gear 38 and the sun pinion 42.

[0034] In a known manner, the arrangement of the differential gear 22 not only allows the driving of the first local time HT display member 6 including the minute display member and the second GMT time display member 8 by the motor engine 2 through a first input portion, but also allows simultaneous correction of the first local time HT display member 6 including the minute display member and the second GMT time display member 8 by a first correction mechanism 23, as well as correction of the second GMT time display member 8 independent of the first local time HT display member 6 by a second input portion.

[0035] According to the invention, the timepiece 1 comprises a gear train 48 mounted in parallel to the drive mechanism 34 of the second display member 8, said parallel mounted gear train 48 being kinematically coupled in an engageable and disengageable manner to the drive wheel 10 of the first display member 6 and to the output part of the differential gear 22 by a first jumper 52 connected to a first star 50 and to the output part of the differential gear 22 linked to said parallel mounted gear train 48 and cooperating with said first star 50, so that said output part is driven by said parallel mounted gear train 48 during the simultaneous correction of local time HT and GMT time by the first correction mechanism 23, and that said output part is disconnected from said parallel mounted gear train 48 to enable disengagement of said output during the correction of GMT time independent of local time HT by the second correction mechanism 32, while allowing a repositioning of the second display member 8 synchronized with the positioning of the first display member 6 after either one of the corrections.

[0036] The parallel mounted gear train 48 advantageously includes an additional wheel 54 rotatably mounted coaxially with the shaft 40 of the differential gear 22, as shown by Figure 4. The additional wheel 54 advantageously has a tube 54 within which the shaft 40 rotates, ensuring that said shaft is better held.

[0037] The additional wheel 54 is adapted to be kinematically linked to the drive wheel 10 of the first display member 6, more particularly to the hour wheel 12 adapted to cooperate with the aforementioned parallel mounted gear train 48. For this purpose, as shown in Figure 5, an intermediate wheel 56 is provided, consisting of two-stage pinions 56a, 56b which are integral with one another, the pinion 56a adapted to cooperate with the hour wheel 12 of the drive wheel 10 and the pinion 56b adapted to cooperate with the additional wheel 54 of the parallel mounted gear train 48.

[0038] With reference to Fig. 4, the additional wheel 54 carries the first star 50 in an integral manner. As regards the first jumper 52, the first jumper 52 is mounted on a plate 58 which is coaxial with the additional wheel 54 and is integral with the shaft 40 constituting the output of the differential gear 22. More specifically, the first jumper 52 comprises a first end 52a pivotally mounted on the plate 58, the pivot shaft of which is mounted on the plate 58 in an integral manner and cooperates with the first star 50, as shown by Fig. 6, in which the additional wheel is not shown, and a second end 52b mounted on said plate 58 in an integral manner.

[0039] The first jumper 52 is therefore adapted to connect an additional wheel 54 to the output of the differential gear 22 in a manner that can be disengaged by means of the star 50, so that said output is isolated from said additional wheel 54 during the correction of the GMT time independent of the local time HT by the second correction mechanism 32.

[0040] The parallel mounted gear train 48 is advantageously such that it is capable of driving said output part at the same speed as the first input part of the differential gear 22 drives the output part of the differential gear 22 when said gear train 48 and output part are connected or engaged by the star 50 / jumper 52 link, i.e. during the driving of the first local time HT display member 6 and the second GMT time display member 8 by the motor-engine 2 and during the simultaneous correction of the first local time HT display member 6 and the second GMT time display member 8 by the first correction mechanism 23.

[0041] Advantageously, and with reference to Figures 2 and 7, the second correction mechanism 32 notably comprises a correction gear train 60 cooperating with the planetary gear carrier 44 constituting the second input of the differential gear 22. Said correction gear train is particularly advantageously adapted to allow a preferably stepwise correction of the second GMT hour display member 8 independent of the local time HT, i.e. independent of the first local time HT display member 6 and of the minute display member.

[0042] In the variants illustrated in Figures 2 to 8, the watch comprises a first display device 61 adapted to display locations associated with various time zones. Said first device 61 for displaying locations is advantageously of the roller display device type adapted to display cities representative of the various time zones.

[0043] For example, the first device 61 for displaying locations as mentioned above comprises a main drum 62 which carries between its two cheeks 62a, 62b eight triangular prismatic elements 63 which are mounted for rotation about their respective longitudinal axes. Each of the three faces of each element 63 is engraved with a location corresponding to one time zone so as to enable the display of 24 time zones by all eight elements 63. Each prismatic element 63 carries at one end a gear 63a adapted to cooperate with a fixed pawl (not shown) to advance each element 63 by 1 / 3 of a rotation for one rotation of the main drum 62. Thus, three rotations of the main drum 62 are necessary to display 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.

[0044] As shown in Figures 2 and 7, the first display device 61 is provided on a chain between the second correction mechanism 32 and the planetary gear carrier 44 constituting the second input part of the differential gear 22, in order to make it possible to correct said location during correction by the second correction mechanism 32 independent of the local time HT of the second GMT time display member 8 linked to the location indicated by the first display device 61.

[0045] The second correction mechanism 32 is advantageously adapted to perform stepwise corrections. For this purpose, it comprises two collectors, for example pushers (not shown) adapted to be actuated by the user to actuate in one direction or another, respectively, a control 64 having two arms cooperating with a star 66 with eight points attached in an integral manner to one of the ends of the arbor 67 of the main drum 62. The control 64 is adapted to advance the star 66 step by step in one direction or another depending on the collector used. Thus, for each correction on demand by applying pressure to the collector, the star 66 advances by 1 / 8 of a turn and drives the main drum 63 by 1 / 8 of a turn to display one face of the next element 63, while the element 63 passing in front of the fixed jaw advances by 1 / 3 of a turn. The corrections are continued until the face of the element 63 corresponding to the selected city appears.

[0046] The correction gear train 60 of the second correction mechanism 32 includes a first wheel 68 integral with the arbor 67 of the main drum 62, and a second wheel 70 which meshes with the first wheel 68 on the one hand and with various intermediate wheels 72 mounted on a frame on the other hand, the last of which meshes with the planetary gear carrier 44.

[0047] It is clear that the push part may also be replaced by a correction stem adapted to have a certain rotation angle, which is preferably controlled in order to control the rotation angle of the planetary gear carrier 44 and thus the rotation angle of the second indicating member 8 during correction alone.

[0048] The bidirectional correction obtained by the two collectors for actuating the control 64 advantageously makes it possible to correct the location and second display member 8 in one direction or another.

[0049] It is of course possible to use only a single collector so that the correction is unidirectional.

[0050] In a variant of the invention, the first device 61 for displaying cities representing various time zones may be replaced by a second display device 74 as shown in FIG. 9, adapted to directly and immediately display the difference between local time HT displayed by the first display member 6 and GMT time displayed by the second display member 8.

[0051] The second display device 74 comprises a fixed dial 75 graduated from 0 to 24, an indicator 76 fixedly mounted on the dial 75, for example in the form of a fixed circular sector positioned around 0 (HT=0) serving to define local time HT as a reference point, and a third display member 78, such as a hand, mounted in a rotationally movable manner 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 time difference value between local time HT(0) and the selected GMT time, for example here indicating a time difference of +10h between GMT time and local time HT, as shown in FIG.

[0052] Thus, the second display device 74 allows to directly show the user the 0 to 24 hour difference between two time zones among the 24 possible time zones.

[0053] According to another variant not shown, the fixed dial 75 is not graduated 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 by means of the third display member 78 to directly indicate to the user the time difference from 0 to 12 hours in one direction or the other.

[0054] As in the case of the first display device, the second display device 74 is provided in a chain between the second correction mechanism 32 and the planetary gear carrier 44 constituting the second input of the differential gear 22 in order to enable correction of the difference between local time HT and GMT time displayed by the third display member 78 during correction of the second GMT time display member 8 by the second correction mechanism 32 independent of local time HT.

[0055] For this purpose, the third indicating member 78 is kinematically linked to the second correction mechanism 32 and to the second input part of the differential gear 22. More specifically, the second correction mechanism 32 comprises a control adapted to rotate the third indicating member 78 in one direction or another depending on the time difference to be displayed, and a corrector gear train kinematically linking the third indicating member 78 to the second input part of the differential gear 22, said corrector gear train including, like the corrector gear train 60, a first wheel meshing with the third indicating member 78 and a last wheel meshing with the planetary gear carrier 44.

[0056] It is clear that the first device for indicating the location 61 or the second time difference indicating device 74 may not be present. In this case, the second correction mechanism 32 is such that the cooperation between the collector and the planetary gear carrier 44 takes place exclusively via the correction gear train 60.

[0057] The watch 1 advantageously includes a third correction mechanism 90 of the first local time HT display member 6, which is separate from the first and second correction mechanisms, and which is adapted to cooperate with said first local time HT display member 6 in order to make it possible to drive only said first local time HT display member 6 during the correction of local time HT, i.e. without the minute display member, which first display member 6 is then separated from the remainder of the drive wheel 10 and from the drive mechanism 34 of the second GMT hour display member 8.

[0058] The third correction mechanism 90 is preferably adapted to perform a stepwise correction of the first display member 6 alone to ensure synchronized repositioning with the minute display member and the second display member 8 after correction of the first display member 6.

[0059] 2 and 8, the third corrector mechanism 90 of the first display member 6 comprises a sawtooth corrector wheel 92 which is mounted in a rotationally movable manner on the tube of the hour wheel 12 and which carries the first display member 6 in an integral manner. The corrector wheel 92 is connected to the hour wheel 12 in a disengageable manner.

[0060] The third correction mechanism 90 of the first display member 6 also includes a correction pawl 94 that can be operated by a user, and this correction pawl 94 is adapted to operate the correction wheel 92 by disengaging it from the rest of the drive wheel 10 in order to drive only the first display member 6 independently of the minute display member and the second display member 8 for stepwise correction.

[0061] More specifically, the hour wheel 12 carries in an integral manner a second star 96, and the corrector wheel 92 carries in an integral manner a second jumper 98, which cooperates with said second star 94 and is adapted to connect the hour wheel 12 in a disengageable manner to said corrector wheel 92. Thus, said corrector wheel 92 is separated from said hour wheel 12 by the corrector pawl 94 during the correction of the first local time HT display member 6, so that only the first display member 6 is moved for its operation.

[0062] During normal operation of the watch, the various mechanisms operate as follows: the motor engine 2 drives the cannon pinion 14 which in turn drives the minute indicator member and hour wheel 12 via the minute wheel 18 and the minute pinion 20. The hour wheel 12 drives the first local time indicator member 6 via a corrector wheel 92 which is connected to the hour wheel 12 by a star 96 / jumper 98 assembly.

[0063] The drive pinion 21, integral with the hour wheel 12, is also driven and in turn drives the sun gear 38 of the differential gear 22. The planetary pinion 46 constitutes a simple intermediate wheel, since the planetary gear carrier 44 is stopped by the first device for indicating the place 61 and the star 66 is held by its jumper 69. The sun gear 38 meshes with the planetary pinion 46, which in turn meshes with the sun pinion 42 to drive the shaft 40, the rotation of which results in the rotation of the second display member 8 to indicate GMT hours without driving the main drum 62.

[0064] At the same time, the hour wheel 12 meshes with the pinion 56a and thus with the pinion 56b of the intermediate wheel 56, said pinion 56b meshing with an additional wheel 54 of the gear train 48 mounted in parallel. The additional wheel 54 is connected to the shaft 40 via the star 50 / jumper 52 assembly such that the shaft 40 is also driven by the additional wheel 54 at the same speed as the driving speed via the sun gear 38.

[0065] The parallel mounted gear train 48 allows the play due to the differential gear 22 alone to be reduced in relation to the aforementioned parallel mounted gear train 48. The play of such a gear train, which simply includes an intermediate wheel 56 connected to an additional wheel 54, is much less than the play associated with the differential gear 22. In addition, the behavior of the shaft 40 is strengthened due to its connection to the additional wheel 54 via the star 50 / jumper 52 assembly. Thus, during normal operation of the piece, the position of the second GMT hour indicator member 8 remains perfectly synchronized with the position of the first local time HT indicator member 6 with respect to the position of the minute indicator member, and the play of the parallel mounted gear train, which contributes to the play between the local time HT and the GMT time, is significantly reduced.

[0066] The size and number of teeth of the various gears are selected, for example, to have a GMT time display over 24 hours. It is clear that GMT time may also be displayed over 12 hours, and the size and number of teeth of the various gears adapted accordingly.

[0067] During the simultaneous correction of the local time HT and the GMT time, the user activates the winding stem 24, which is moved to its hand-turning position to engage the clutch wheel 26 with the first intermediate wheel 28. The cannon pinion is separated from the motor engine 2 by the friction 16. During the rotation of the stem 24, the first intermediate wheel 28 driven by the clutch wheel 26 drives the other intermediate wheel 30, which in turn drives the minute wheel 18 and the minute pinion, respectively, to perform the hand-turning of the local time HT by moving the HT hour display member and the minute display member. As mentioned above, the drive pinion 21, which is integral with the hour wheel 12, meshes with the sun gear 38 of the differential gear 22, and at the same time, the hour wheel 12 meshes with the gear train 48 mounted in parallel, to effect the rotation of the shaft 40 without driving the main drum 62, and thus the rotation of the second display member 8 for the correction of the second display member 8. As mentioned above, the play caused by the parallel mounted gear train 48 is much less than the play caused by the differential gear 22. In addition, the use of the stem 24 allows bidirectional correction of the HT and GMT hours. Thus, during hand turning or simultaneous and bidirectional correction of the local time HT and GMT hours, the position of the second GMT hour display member 8 remains perfectly synchronized with the position of the first local time HT display member 6 with respect to the position of the minute display member, and the play of the parallel mounted gear train, which contributes to the play between the local time HT and GMT hours, is greatly reduced.

[0068] During the correction of the GMT time and place, if the device 61 for displaying the place is present, the user activates one of the collectors of the second correction mechanism 32 by applying a continuous pressure in order to activate the main drum 62 and its elements 63 until the desired place is displayed. At the same time, the correction gear train 60 is driven to drive the planetary gear carrier 44 of the differential gear 22. Due to the differential gear used, it is considered that the sun gear 38 does not vary with respect to the correction speed, so that the planetary pinion 46 carried by the planetary gear carrier 44 slides on the one hand on the inner toothing of the sun gear 38 and on the other hand meshes with the sun pinion 42, thereby driving the shaft 40 and thus the second member display 8. It is also considered that the additional wheel 54 does not vary with respect to the correction speed, so that the shaft 40 breaks the connection with the additional wheel 54 and the jumper 52 no longer cooperates with the star 50 and jumps over one tooth of the star 50.

[0069] The element 63 of the main drum 62 and the second GMT hour display member are simultaneously corrected independently of the first local time HT display member 6 and the minute display member due to the differential gear 22, and the star 50 / jumper 52 assembly connected to the shaft 40 of said differential gear 22 enables said shaft 40 to change position precisely relative to the position of the first display member 6 after each correction of the second GMT hour display member 8, the jumper 52 jumping over one tooth of the star 50 to change position precisely between the subsequent teeth, so that the position of said second GMT hour display member 8 remains perfectly synchronized with the first local time HT display member 6 with respect to the position of the minute display member.

[0070] In addition, the use of a graduated corrector makes it possible to precisely control the angles of rotation of the various gear trains during the correction of the GMT time and place in order to enhance the accuracy of the repositioning of the shaft 40 and therefore of the second GMT time indicating member 8 after its correction.

[0071] Similarly, during the correction of the difference between local time HT and GMT time when the second display device 74 is present, when correcting GMT time alone, the user activates the second correction mechanism 32 to move the third display member 78 until the desired time difference is displayed on the dial 75. At the same time, the correction gear train of the second correction mechanism 32 is driven so as to drive the planetary gear carrier 44 of the differential gear 22, drive the shaft 40 and thus drive the second GMT time display member 8. As mentioned above, the third display member 78 and the second GMT time display member 8 are simultaneously corrected independently of the first local time HT display member 6 and the minute display member by the star 50 / jumper 52 assembly which is connected to the differential gear 22, to the shaft 40 of said differential gear 22 and allows the shaft 40 to be precisely repositioned relative to the position of the first display member 6 after each correction of the third member 78 to display the difference between local time HT and GMT time and each correction of the second GMT time display member 8.

[0072] During correction of the first HT hour display member 6 alone, for example during the first adjustment after purchase of the watch or during the transition from summer time to winter time (which may take place on different days depending on the time zone), the user activates the corrector pawl 94 to separate the corrector wheel 92 from the rest of the drive wheel 10, and the jumper 98 no longer cooperates with the star 96. The gradual correction of the corrector wheel 92, which is integral with the first display member 6, makes it possible to advance only said first display member 6 by one hour without driving the minute display member or the second GMT hour display member 8. The position of the first local time HT display member 6 thus remains perfectly synchronized with the position of the second GMT hour display member 8 with respect to the position of the minute display member.

[0073] The timepiece according to the invention therefore makes it possible to simultaneously correct the location and GMT time without correcting the local time HT, to turn the hands without correcting the displayed location or to simultaneously and bidirectionally correct the local time HT and GMT time, as well as to correct only the local time HT display member 6, thereby ensuring, after one or the other of these corrections, the positioning of the second GMT time display member that is permanently synchronized with the positioning of the first HT display member with respect to the position of the minute display member.

Claims

1. a motor engine (2); at least one first display member (6) adapted to display local time HT; a second display member (8) adapted to be able to display GMT time in a time zone different from the time zone of the local time HT; a drive wheel (10) of the first display member (6) adapted to be kinematically coupled to the motor engine (2) in an detachable manner; a first correction mechanism (23) adapted to be kinematically coupled to the drive wheel (10) of the first display member (6) to enable simultaneous correction of the local time HT and the GMT time; and a second correcting mechanism (32) of the second display member (8) that is separate from the correcting mechanism (23) of the first display member (6) and that is capable of correcting the GMT time independently of the local time HT, and the second display member (8) includes a differential gear (22) that has at least one first input portion kinematically coupled to the drive wheel (10) of the first display member (6), a second input portion kinematically coupled to the second correcting mechanism (32) of the second display member (8), and an output portion that is adapted to drive the second display member (8). and a drive mechanism (34) of the second display member (8), comprising a gear train (48) mounted parallel to the drive mechanism (34) of the second display member (8), the gear train (48) being connected to a first star (50) connected to the parallel mounted gear train (48) and to the output of the differential gear (22) and being kinematically coupled to the drive wheel (10) of the first display member (6) in an detachable manner and to the output of the differential gear (22) by a first jumper (52) cooperating with the first star (50). a timepiece (1) in which the output unit is driven by the parallel mounted gear train (48) during simultaneous correction of the local time HT and the GMT time by the first correction mechanism (23), and the output unit is decoupled from the parallel mounted gear train (48) during correction of the GMT time independent of the local time HT by the second correction mechanism (32), while allowing repositioning of the second display member (8) synchronized with the positioning of the first display member (6) after correction.

2. 2. Timepiece according to claim 1, characterized in that the parallel mounted gear train (48) comprises an additional wheel (54) rotatably mounted coaxially with the differential gear (22) and kinematically coupled to the drive wheel (10) of the first display member (6), the additional wheel (54) carrying the first star (50), the first jumper (52) connecting the additional wheel (54) to the output of the differential gear (22), so that the output is isolated from the additional wheel (54) during correction of the GMT time independent of the local time HT by the second correction mechanism (32).

3. 3. A timepiece according to claim 2, characterized in that the first jumper (52) comprises a first end (52a) pivotally mounted on a plate (58) coaxial with the additional wheel (54) and integral with the output of the differential gear (22), the first end (52a) cooperating with the first star (50), and a second end (52b) integral with the plate (58).

4. 4. A timepiece according to any one of claims 1 to 3, characterized in that the parallel mounted gear train (48) is capable of driving the output part of the differential gear (22) at the same speed as the first input part of the differential gear (22) drives the output part when the gear train (48) and the output part of the differential gear (22) are coupled.

5. 4. Timepiece according to any one of claims 1 to 3, characterized in that the drive wheel (10) of the first display member (6) comprises an hour wheel (12) adapted to be kinematically coupled to the motor-engine (2) in an detachable manner and adapted to drive the first display member (6), the hour wheel (12) cooperating on the one hand with the first correction mechanism (23) and on the other hand with the parallel mounted gear train (48), and a drive pinion (21) kinematically coupled to the first input of the differential gear (22).

6. 6. A timepiece according to claim 5, characterized in that it includes an intermediate wheel (56) adapted to cooperate on the one hand with the hour wheel (12) of the drive wheel (10) of the first display member (6) and on the other hand with the additional wheel (54) of the parallel-mounted gear train (48).

7. 4. Timepiece according to any one of claims 1 to 3, characterized in that the differential gear (22) comprises a first sun gear (38) constituting the first input part, mounted rotatably on an axle (40) constituting the output part of the differential gear (22) and carrying a sun pinion (42), and a second planet gear carrier (44) constituting the second input part, carrying at least one planet pinion (46) meshing with both the first sun gear (38) and the sun pinion (42).

8. 4. Timepiece according to any one of claims 1 to 3, characterized in that the first correction mechanism (23) comprises a hand-driving stem (24) adapted to drive the drive wheel (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. 4. Timepiece according to any one of claims 1 to 3, characterized in that the second correction mechanism (32) comprises a corrector gear train (60) adapted to cooperate with the second input of the differential gear (22) and to enable a stepwise correction of the second display member (8) independent of the local time HT.

10. 4. A timepiece according to claim 1, comprising a first display device (61) adapted to display locations linked to various time zones, the first device (61) for displaying said locations being provided on a chain between the second correcting mechanism (32) and the second input of the differential wheel (22) in order to enable correction of the displayed locations during correction by the second correcting mechanism (32) of a second GMT hour display element (8) linked to said locations, independent of the local time HT.

11. 11. A watch according to claim 10, characterized in that the first device (61) for displaying a location is a roller display device adapted to display a city.

12. 12. Timepiece according to claim 11, characterized in that it comprises a second display device (74) adapted to display the difference between the local time HT and the GMT time, said second display device being provided on a chain between said second correcting mechanism (32) and said second input of said differential wheel (22) in order to enable correction of the difference between the displayed local time HT and the GMT time during correction of said second GMT hour display member (8) by said second correcting mechanism (32) independent of said local time HT.

13. 13. Timepiece according to claim 12, characterized in that the second display device (74) comprises a dial (75), an indicator (76) fixedly mounted on the dial (75) and adapted to define the local time HT as a reference point, and a third display member (78) mounted in a manner that allows it to be rotated relative to the dial (75), the position of the third display member (78) on the dial (75) relative to the indicator (76) indicating the difference between the local time HT and the GMT time, and the third display member (78) is kinematically connected to the second corrector mechanism (32) and the second input part of the differential wheel (22).

14. 4. A timepiece according to any one of claims 1 to 3, characterized in that it includes a third correcting mechanism (90) of the first display member (6) that is separate from the first and second correcting mechanisms (23, 32) and that is adapted to cooperate with the first local time HT display member (6) in order to enable only the first local time HT display member (6) to be driven during the correction of the local time HT.

15. 15. The timepiece according to claim 14, characterized in that the third correction mechanism (90) of the first display member (6) includes a corrector wheel (92) that is integral with the first display member (6) and is connected to the hour wheel (12) in an engageable and disengageable manner, and a corrector pawl (94) that is adapted to operate the corrector wheel (92) by engaging and disengaging from the corrector wheel (92) so as to drive only the first display member (6) for stepwise correction.

16. 16. Timepiece according to claim 15, characterized in that the hour wheel (12) carries a second star (96) and the corrector wheel (92) carries a second jumper (98) adapted to cooperate with the second star (96) and to connect the hour wheel (12) to the corrector wheel (92), so that the corrector wheel (92) is separated from the hour wheel (12) during the correction of the first display member (6) of the local time HT by the corrector finger (94).

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