Timepiece calendar system

Abstract

Clock calendar system (200), the system comprising: - a date wheel (4) movable step by step relative to a frame (199); - a first finger (21) for driving the date wheel (4); - a first tooth (51) for driving the date wheel (4), the first tooth (51) being mounted movable on the date wheel (4) between a deactivated or retracted position and an activated or driving position; - an activation system (6, 7) for the first tooth (51); the first driving finger (21) and the first tooth (51) being arranged so that a single action of the first driving finger (21) on the first tooth (51) can cause a displacement of the date wheel (4) by N steps, N being an integer such that N>1, in particular N=2 or N=3.

Description

[0001] The invention relates to a clockwork calendar system. The invention also relates to a clockwork movement comprising such a clockwork calendar system. The invention further relates to a timepiece comprising such a clockwork movement or such a clockwork calendar system. The invention also relates to a method of operating such a clockwork calendar system, such a clockwork movement, or such a timepiece. Finally, the invention relates to a transmission system that can be used to equip such a clockwork calendar system, such a clockwork movement, or such a timepiece.

[0002] Document EP3567438 describes an embodiment of a calendar system, in particular an annual calendar system, comprising a drive device with a single drive element. This drive element includes a first finger for actuating one of the thirty-one teeth of a date disc to allow a first jump of said date disc, thus enabling the date to advance regardless of the date, and an additional finger, angularly offset from the first finger, for actuating a tooth of a finger movably mounted on the date disc to allow a further jump of said date disc at the end of a month of thirty days or fewer. Advantageously, the drive device includes a calendar cam and a spring-loaded rocker.The cooperation of the cam and the rocker allows an instantaneous rotation of the drive wheel, which allows an instantaneous change of date regardless of the number of jumps made by the date disc.

[0003] Document CH680630 also discloses a drive mechanism with a single drive wheel, specifically within a perpetual calendar system. This solution is difficult to reconcile with the implementation of an instantaneous jump drive. Indeed, the displacement of the drive wheel required to enable the multiple jumps of the date wheel during the unwinding of a hypothetical elastic lever would need to be maximized. The winding of the elastic lever, which would also need to be maximized, would thus occur over a limited displacement of the drive wheel, leading to abrupt torque variations that could cause significant amplitude drops in the oscillator, particularly in a balance-spring type oscillator.

[0004] It is therefore necessary to define an instantaneous jump drive device suitable for the implementation in particular of a semi-perpetual or perpetual calendar, which allows to reduce as much as possible the energy losses at the level of the oscillator, while being compact.

[0005] Document EP0987609 describes a first drive unit with a fixed axis of rotation relative to a frame, and a second drive unit with a movable axis of rotation relative to the same frame. However, the drive finger of the second unit is designed to drive a tooth fixed to a date disc. In this design, the second unit is mounted on a rocker arm movable relative to the frame against a return spring, generating unnecessary energy consumption that is difficult to reconcile with the implementation of an instantaneous jump drive.

[0006] Document CH710109 describes a calendar system comprising a first drive wheel with a fixed axis of rotation relative to a frame, and a second drive wheel with a fixed axis of rotation relative to the same frame. However, the drive finger of the second wheel is designed to drive an additional tooth fixed to a date wheel. To implement the calendar system according to document CH710109, the finger of the second wheel is mounted to move against a month programming cam located coaxially with the second wheel, under the action of a return spring. This return spring induces unnecessary energy consumption and generates torque fluctuations throughout the day, which is difficult to reconcile with the implementation of an instantaneous jump drive.On the other hand, the month programming cam is particularly bulky, leaving little space for installing a calendar cam and an elastic rocker within the drive mechanism. Furthermore, the placement of the month programming cam coaxially with the second moving part dictates, at least partially, the positioning of the second moving part's axis relative to the frame, which can be a limiting factor in optimizing the date wheel's drive under the actuation of the second moving part's drive finger. Finally, this finger completes a full rotation around the month programming cam every day, which can lead to premature wear of the drive mechanism, especially if the second finger is elastically returned against the cam by a return spring.

[0007] US patent 3,716,983 A discloses a clockwork calendar system, the system comprising a date wheel movable step by step relative to a frame, a first date wheel drive finger, and a first date wheel drive tooth, the first tooth being mounted movable on the date wheel between a deactivated or retracted position and an activated or drive position.

[0008] The aim of the invention is to provide a clockwork calendar system that improves upon known prior art systems and solves the aforementioned problems. In particular, the invention proposes a simple, efficient, and compact clockwork calendar system that is also compatible with an annual, semi-perpetual, or perpetual calendar system.

[0009] The attached drawings represent, as an example, one method of manufacturing a timepiece. There figure 1is a schematic view of one embodiment of a timepiece. figures 2 And 6 These are views of one embodiment of a calendar system fitted to the timepiece. figures 3 And 4 These are respectively top and bottom views of a drive device for a mobile calendar display. figure 5 is an exploded view of a drive unit. The figures 7 to 16 These are illustrative views of how the calendar system implementation works. Figures 17 to 20 These are illustrative views of the operation of a motion transmission system according to the invention. figure 21 is a detailed view of the geometry of a pinion that is part of the motion transmission system.

[0010] A method for manufacturing a 400 timepiece is described in detail below with reference to figures 1 to 21A timepiece (part 400) is, for example, a watch, specifically a wristwatch. A timepiece (part 400) includes a watch movement (part 300), designed to be housed in a watch case or box to protect it from the external environment. The watch movement (part 300) can be a mechanical movement, such as an automatic movement, or a hybrid movement. Alternatively, the movement (part 300) can be an electronic or electromechanical movement.

[0011] The 300 watch movement includes a 200 calendar system. Specifically, the 200 calendar system may be a calendar module attached to the rest of the movement. The movement and / or the calendar module includes a frame 199 comprising, for example, one or more plates and possibly bridges.

[0012] In the described embodiment, the calendar system is semi-perpetual and displays the date, day, and month. Alternatively, the calendar can be of any other type, including annual or perpetual. The calendar system can display any other set of indications.

[0013] The 200 clock calendar system includes: a mobile of the calendars 4 movable step by step relative to the frame 199, and a drive device 100.

[0014] The 100 training device includes: a finger 21 for driving the date wheel 4; a tooth 51 for driving the date wheel 4, the tooth 51 being mounted movablely on the date wheel 4 between a deactivated or retracted position and an activated or driving position; and an activation system 6, 7 for the tooth 51.

[0015] The date wheel 4, which may in particular include a date disc 4, is preferably centered on the calendar system 200 or on the movement 300 along an axis A4. The date wheel 4 comprises a gear 41 with 31 teeth, and a finger 5 movably mounted on said wheel 4, in particular pivotally mounted on said wheel 4 along an axis of rotation A5. The finger 5 includes the tooth 51 at one of its ends, in particular at a longitudinal end opposite to that on which the axis of rotation A5 is located. In a first configuration of the calendar system, in particular in a first configuration of the activation system 6, 7 which may be called the deactivated configuration, the tooth 51 is movable relative to the wheel 4.In a second configuration of the calendar system, in particular in a second configuration of the activation system 6, 7 which can be called the activated configuration, the tooth 51 is immobile relative to the mobile 4.

[0016] Preferably, the teeth 41 take the form of internal teeth, and the tooth 51 is oriented inwards. In other words, the teeth of the teeth 41 and the tooth 51 are preferentially oriented towards the axis A4.

[0017] Advantageously, the head radius RT5 (defined from axis A4) of tooth 51 is different from the head radius RT4 (defined from axis A4) of the teeth of gear 41, when tooth 51 is stationary relative to the moving part 4, in particular stationary about axis A5 as illustrated in the figure 6Preferably, the head radius RT5 is less than the head radius RT4, or even less than 0.9xRT4, when the tooth 51 is stationary relative to the moving part 4, particularly when stationary about the axis A5. In other words, the tooth 51 protrudes or is likely to protrude from the teeth 41. Such a tooth 51 configuration maximizes the driving of the moving part 4 when the latter is driven by the interaction between the tooth 51 and the drive device 100. More specifically, such a tooth 51 configuration allows the moving part 4 to potentially be actuated through several angular steps when the latter is driven by the interaction between the tooth 51 and the drive device 100.

[0018] The finger 5 is capable of cooperating with a follower 6, in particular a rocker 6 mounted pivotally about an axis A6 on the frame 199 of the calendar system 200 or the movement 300. To do this, the finger 5 includes a contact surface 52 intended to cooperate by contact with a flank 62 of the follower 6. The follower 6 also includes a pin or pawl 61 intended to be housed in a groove 71 of a month cam 7 taking here an annular shape.

[0019] The flanks 71a, 71b of the groove 71 of the cam 7 respectively act as cam profiles 71a, 71b, which are intended to control the position of the follower 6, in particular the angular position of the follower 6 around the axis A6, via the pin 61, and this independently of any return spring.

[0020] The follower 6 and the cam 7 are thus part of the activation system 6, 7 of the finger 5 or the tooth 51. Preferably, the follower 6 and the cam 7 define a desmodromic system 6, 7 arranged such that: to allow the mobility of finger 5 or tooth 51 around axis A5 in at least one position of mobile 4, and to prohibit the mobility of finger 5 or tooth 51 around axis A5 in at least one position of mobile 4, in particular in at least one position of mobile 4 corresponding to the aforementioned position of mobile 4.

[0021] More specifically, at least one first position of the cam 7 defines a first position of the follower 6 allowing mobility of the finger 5 or the tooth 51 around the axis A5 in at least one position of the mobile 4. More specifically, at least one second position of the cam 7 defines a second position of the follower 6 prohibiting mobility of the finger 5 or the tooth 51 around the axis A5 in at least one position of the mobile 4. In this latter configuration, the tooth 51 is projecting from the teeth 41 in the described embodiment.

[0022] The implementation of the activation system 6, 7 allows the programming of an annual, semi-perpetual, or perpetual cycle to be governed, as will be described below.

[0023] Preferably, the cam 7 is centered on the calendar system 200 or on the movement 300 along an axis A7. Thus, preferably, the axes A4 and A7 coincide. In other words, the moving part 4 and the cam 7 are preferably arranged coaxially. The moving part 4 and the cam 7 are advantageously linked by a transmission system which will be described in detail below. Preferably, the cam 7 comprises a toothed section 72 capable of being periodically driven by teeth of a toothed section 42 of the moving part 4, via a pinion 8 pivoted about an axis A8, as will be described below.

[0024] Preferably, the tooth 42 takes the form of an external tooth and the tooth 72 takes the form of an internal tooth.

[0025] The 200 calendar system also includes a 9-day star, which is preferably centered on the 200 calendar system or the 300 movement along axis A9. Thus, axes A4, A7, and A9 preferably coincide. In other words, elements 4, 7, and 9 are preferably arranged coaxially. Specifically, the 9-day star has a 91-toothed mechanism with seven teeth.

[0026] The moving part 4 and the star 9 are angularly indexed in position relative to the frame 199 by means of jumpers 98 and 99 respectively (the latter being schematically represented on the figure 2). The cam 7 is, for its part, angularly indexed relative to the frame 199 by the mobile 4, via the pinion 8. More particularly, this pinion 8 is specifically shaped so as to allow angular locking with less play of the cam 7 when the latter is not driven by one of the teeth of the toothing 42 of the mobile 4, as will be described below.

[0027] The mobile 4 and the star 9 are shaped and / or arranged so that they can be driven periodically, in particular every 24 hours, by the drive device 100. The cam 7 is shaped and / or arranged so that it can be driven periodically, at each end and possibly at each beginning of each month, by the drive device 100 via the mobile 4 and the pinion 8.

[0028] THE figures 3 And 4illustrate respectively a top and bottom view of the drive unit 100. The drive unit 100 is connected to the finishing gear of the movement 300 by means of an hour wheel 201.

[0029] The drive device 100 comprises a drive wheel 1 pivoted about an axis A1 and having a drive finger 11 fixed in rotation to a wheel 12. The drive finger 11 is configured and / or arranged so as to drive the wheel 4 every 24 hours by cooperating through contact with one of the teeth of the gear 41. The drive finger 11 is also configured to stop the wheel 4 after driving said wheel 4. The drive is advantageously of the instantaneous type.

[0030] More specifically, the drive finger 11 comprises a first rigid part 11a, as well as a second elastic part 11b. Such a drive finger configuration advantageously allows for rapid correction of the date when the finger 1 is located between two teeth of the gear train 41, particularly after a date jump, as taught in document EP3483663.

[0031] The drive finger 11 is oriented outwards here. In other words, the drive finger 11 extends radially relative to axis A1, moving away from said axis A1, specifically until it reaches a circle of radius RT1 (for Head Radius) centered on axis A1, as illustrated in the Figure 6 Furthermore, axis A1 is here positioned on a circle of radius R1, which is centered on axis A4.

[0032] The drive device 100 also includes a drive wheel 2 pivoted about an axis A2, which has a drive finger 21. This finger 21 is rotationally fixed to a wheel 22. The drive finger 21 is designed to drive the wheel 4 by cooperating through contact with the tooth 51 of the finger 5, particularly when the follower 6 prevents the finger 5 or the tooth 51 from moving about the axis A5. This drive occurs at the end of each month of thirty days or less. The drive wheel 2 also has a drive finger 23 that is rotationally fixed to the wheel 22. The drive finger 23 is designed to drive the star wheel 9 by cooperating through contact with one of the teeth of the gear 91.

[0033] The drive finger 21 is oriented outwards. In other words, the drive finger 21 extends radially relative to axis A2 away from said axis A2, specifically until it reaches a circle of radius RT2 (for Head Radius) centered on axis A2, as illustrated in the figure 6 Furthermore, axis A2 is here positioned on a circle of radius R2, which is centered on axis A4.

[0034] Advantageously, the radius RT2 differs from the radius RT1. More specifically, the radius RT2 is greater than the radius RT1, even greater than 1.5×RT1, or even greater than 1.8×RT1. Advantageously again, the radius R2 differs from the radius R1. More specifically, the radius R2 is advantageously less than the radius R1, even less than 0.9×R1, or even less than 0.8×R1.

[0035] Such a conformation of the drive mobile 2 has the advantage of ensuring that the cooperation by contact of the finger 21 and the tooth 51 allows the mobile 4 to be driven on one or more angular steps of the mobile 4 when the tooth 51 is immobilized relative to the mobile 4, in particular immobilized in rotation around the axis A5, while the conformation of the drive mobile 1 allows the mobile 4 to be driven on a single angular step of the mobile 4.

[0036] Advantageously, such drive mobile conformations 1 and 2 cooperate respectively with a mobile 4 comprising an internal tooth 41 having a head radius RT4, and with an internal tooth 51 having a head radius RT5, the head radius RT5 being less than the head radius RT4, or even less than 0.9×RT4, when the tooth 51 is immobilized relative to the mobile 4, in particular immobilized in rotation about the axis A5.

[0037] The movement of the moving part 4 is thus optimized to allow it to perform, for a single action of the finger 21, up to several jumps or several angular steps. In particular, the drive unit 2 and the moving part 4 are arranged and / or configured so as to allow several jumps or several angular steps of the moving part 4 for a single action of the finger 21. By "a single action of the finger 21," we mean a partial or complete rotation of one turn of the finger 21 around the axis A2.

[0038] Thus, the drive finger 21 and the tooth 51 are arranged so that a single action of the drive finger 21 on the tooth 51 can cause a displacement of the date wheel 4 by N steps, N being an integer such that N>1, in particular N=2 or N=3.

[0039] The drive units 1 and 2 are kinematically connected to each other via a drive unit 3 with axis A3. More specifically, the wheels 12 and 22 are kinematically connected to each other via a wheel 32 of the third unit 3, which is interposed between wheels 12 and 22. In the described embodiment, axis A3 is located on a circle of radius R3, which is centered on axis A4. Preferably, the radius R3 is different from the radii R1 and R2. More specifically, the radius R3 is advantageously greater than the radii R1 and R2. Preferably, R3 > R1 > R2.

[0040] The third moving part 3 also includes a wheel 31, fixed in rotation to the wheel 32 in at least one direction of rotation, which connects the hour wheel 201 to the third moving part 3 via two pinions 202a and 202b fixed to each other. More specifically, wheel 201 drives pinion 202a, and pinion 202b drives wheel 31, which in turn drives wheel 32. The latter thus drives wheels 12 and 22, in particular in the same direction of rotation.

[0041] The drive device 100, in particular the mobiles 1, 2 and 3, is thus connected to the finishing gear of the movement 300 via the hour wheel 201. Advantageously, the mobiles 1 and 2 are arranged on either side of a plane passing through the axis A3 of the drive mobile 3 and through the axis of the movement (in particular coinciding with the axis A4 of the date mobile).

[0042] Advantageously, the drive device 100 includes an instantaneous drive device 92. This mainly comprises a calendar cam 96 and a spring-loaded rocker 97 pivoted on the frame 199. Preferably, the moving part 3, more particularly visible in the exploded view of the figure 5 , includes the calendar cam 96 which is designed to cooperate with the rocker-spring 97, in particular with a roller 971 pivoted on the rocker-spring 97. The cam 96 is notably fixed to the wheel 32. The cooperation of the cam 96 and the rocker-spring 97 allows instantaneous drive of the moving part 4 via the drive wheels 1 and / or 2, in particular the fingers 11 and / or 21, over at least one angular pitch of the moving part 4. The cooperation of the cam 96 and the rocker-spring 97 also allows instantaneous drive of the star 9 via the drive wheel 2, in particular the finger 23, over one angular pitch of the star 9.

[0043] Advantageously, the drive device 100 includes a one-way linkage device 94. Preferably, the third moving part 3 includes the one-way linkage device 94, which allows the wheels 31 and 32 to be linked in rotation in the same direction. This device includes a pawl 941 pivoted on the wheel 31, which is elastically returned by a spring 942, and which can cooperate by contact with a pin or pawl 321 of the wheel 32. The implementation of such a linkage device allows, in particular, correction of the calendar system 200 at any time, regardless of any prior manipulations of the calendar system 200 or the movement 300.

[0044] Throughout the day, the drive mechanism 100 accumulates elastic potential energy through the winding of the spring 972 of the rocker-spring 97, under the effect of the rotation of the cam 96, causing a deformation of the spring 972, the cam 96 being itself driven by the movement 300 via the hour wheel 201. Once the roller 971 reaches the apex 961 of the cam 96 (as shown in the figure 4), the spring 972 returns the accumulated energy and the rocker-spring 97 thus becomes a driving force. The latter guides the cam 96 over a given angular range until the roller 971 is positioned in a recess 962 of the cam 96, which is made possible in particular by the unidirectional link 94. During this phase, namely during the movement of the cam 96 under the effect of the rocker 97, the drive wheel 1, in kinematic connection with the cam 96, instantaneously drives the wheel 4 over an angular step by the cooperation of the finger 11 and a tooth of the gear 41. During this same phase, the drive wheel 2, also in kinematic connection with the cam 96, instantaneously drives the wheel 4 over at least one additional angular step by the cooperation of the finger 21 and the tooth 51 when the latter is immobilized relative to the wheel 4, in particular when the latter is immobilized around the axis A5 under the effect of the activation system 6,7.

[0045] The configuration of the drive device 100 thus allows, for a given displacement of the cam 96 under the effect of the rocker 97, the drive of the moving part 4 by one, two, three, or four angular steps. This is made possible by the fact that the drive device 100 comprises two separate drive parts 1, 2 pivoted about two separate axes A1 and A2, the respective displacements of the fingers 11 and 21 occurring simultaneously and their respective contact with one of the teeth of the gear 41 and the tooth 51 occurring successively. Advantageously, the axes A1, A2 are arranged on circles having distinct radii R1, R2. Advantageously still, the finger 21 has a head radius RT2 different from the head radius RT1 of the finger 11. In particular, the head radius RT2 is greater than the head radius RT1.Thus configured, the drive unit 2, in particular finger 21, is capable of driving the unit 4 over N steps, N being an integer such that N>1, in particular N=2 or N=3.

[0046] Preferably, fingers 11 and 21 rotate at the same speed. Thus, the teeth of wheels 12 and 22, 32, can in particular comprise the same number of teeth and extend over the same level or plane.

[0047] Advantageously, the drive device 100 includes a jumper deactivation device 93. This device 93 includes a jumper cam 95 which is designed to cooperate with the jumper 98, in particular with a roller 981 pivoted on a part 982 forming a spring of the jumper 98. Such a device advantageously makes it possible to reduce, or even eliminate, the indexing or holding torque of the moving part 4 generated by the jumper 98 when the finger 11 drives one of the teeth of the gear 41 and / or when the finger 21 drives the tooth 51, particularly when the cam 96 is driven by the rocker-spring 97, in particular by the release of the energy stored by the spring 972.

[0048] Preferably, the drive unit 1 includes the cam 95 intended to cooperate with the jumper 98.

[0049] Thus, the drive unit 1 preferably includes the jumper cam 95 of a jumper deactivation device 93, in addition to the first finger 11 and the wheel 12. Thus, the drive unit 2 preferably includes a third drive finger 23, in addition to the second finger 21 and the wheel 22. Thus, the drive unit 3 preferably includes the calendar cam 96 of an instantaneous drive device 92, as well as a one-way linkage device 94, in addition to the wheels 31 and 32. However, any other arrangement of the various elements 23, 95, 96 on the various drive units could be considered.

[0050] Such a configuration of the drive elements 1, 2, and 3 allows for the optimal distribution and integration of the various components involved in the drive device 100 and / or the instantaneous drive device 92 and / or the unidirectional link device 94 and / or the jumper deactivation device 93. This has the particular advantage of enabling the implementation of a particularly slim drive device 100 and a fortiori of a particularly slim 200 calendar system.

[0051] An execution method of an operating process of an embodiment of a calendar system 200 is now described in several situations: at the end of a 28-day month (February), at the end of a 31-day month (March), and at the end of a 30-day month (April). Operation at the end of February 28 days

[0052] THE figures 7 to 11illustrate the operation of the calendar system during the transition from the date to the end of a 28-day February. During this phase, the moving part 4 makes four jumps or angular steps. Advantageously, the moving part 4 is actuated by the release of energy stored by the spring 972 of the rocker 97, which drives the calendar cam 96, as well as the fingers 11, 21, until the roller 971 is positioned in the recess 962 of cam 96.

[0053] There figure 7 illustrates the calendar system on February 28 at midnight, just before the jump of mobile 4. In this configuration, the roller 971 begins the descent of the calendar cam 96 from its apex 961 as illustrated on the figure 4 . Finger 21 then comes into contact with tooth 51, while finger 11 is out of reach of tooth 41.

[0054] The tooth 51 is here stationary relative to the moving part 4, in particular stationary around the axis A5, due to the cooperation of the respective surfaces 52 and 62 of the finger 5 and the follower 6. This is made possible by the cooperation of the follower 6 and the cam 7, in particular by the cooperation of the pin 61 and the groove 71 which positions the flank 62 of the follower 6 in such a way that the tooth 51 cannot retract under the actuation of the finger 21. Thus, when the activation system 6, 7 is in this configuration, the contact between the finger 21 and the tooth 51 induces the rotation of the moving part 4 around the axis A4.

[0055] There figure 8 illustrates the calendar system once the mobile 4 has moved a first angular step around the axis A4, after having seen the finger 21 perform a first rotation by an angle α1 around the axis A2. The finger 11 remains here out of reach of the teeth 41 despite the rotation it has already made around the axis A1.

[0056] There figure 9 illustrates the calendar system once the mobile 4 has moved a second angular step around the axis A4, after having seen the finger 21 perform a rotation of a second angle α2 around the axis A2. The finger 11 remains here out of reach of the teeth 41 despite the rotation it has already made around the axis A1.

[0057] There Figure 10 illustrates the calendar system once the mobile 4 has moved a third angular step around the axis A4, after having seen the finger 21 rotate by a third angle α3 around the axis A2. In this configuration, the finger 21 leaves the contact with the tooth 51 and the finger 11 comes into contact with one of the teeth of the toothing 41.

[0058] Thus, finger 21 was in contact with tooth 51 at an angle ϑ = α1+ α2+ α3 around axis A2.

[0059] There figure 11illustrates the calendar system on March 1st, once the mobile 4 has moved a fourth angular step around axis A4, after the finger 11 has rotated by a first angle β1 around axis A1. More specifically, the figure 11 This illustrates the calendar system just after the date has passed, when the roller 971 is in the recess 962 of the cam 96. In this configuration, the finger 11 is positioned between two teeth of the gear 41 such that the finger 11 blocks the moving part 4 and thus prevents any further unwanted jump of said moving part. Preferably, β1 ≥ α1, α2, α3. Preferably, β1 ≤ ϑ.

[0060] Advantageously, the device 93 for deactivating jumper 98 (not shown on the figures 7 to 11) is actuated, in particular by the rotation of the drive unit 1 around the axis A1. Such a device makes it possible to minimize, or even cancel, the indexing or holding torque of the unit 4 when the unit 4 is actuated by the effect of the fingers 11 and / or the fingers 21.

[0061] The day indicator is engaged when finger 23 makes contact with one of the teeth of the 91 toothing of the star 9, which causes the star to rotate. Once the date jump has been made (as shown on the figure 11 The finger 23 is positioned between two teeth of the gear 91 such that the finger 23 blocks the star 9 and thus prevents any further unwanted movement of said star. For example, the finger 23 may come into contact with one of the teeth of the gear 91 of the star 9 at the moment (or approximately at the moment) that the finger 11 comes into contact with one of the teeth of the gear 41.

[0062] During this phase of operation, finger 21 caused the date wheel 4 to move three steps, and finger 11 caused it to move one step. On February 28, just before midnight, the date wheel indicated "28," and on March 1, just after midnight, it indicated "1." The four drive steps of the wheel allowed for the following four successive transitions: from the display of the date "28" to the display of the date "29", then, from the display of the date "29" to the display of the date "30", then, from the display of the date "30" to the display of the date "31", then, from the display of the date "31" to the display of the date "1", during an instant training. Operational at the end of March

[0063] There figure 13 illustrates the state of the calendar system on March 30 at midnight, just before the jump of mobile 4, and the figure 14illustrates the state of the calendar system on March 31 at midnight just before the jump of mobile 4.

[0064] On the figure 13 The follower 6 is positioned here by the cam 7, specifically by the pin 61 and the groove 71, such that the flank 62 of the follower is beyond the reach of the surface 52 of the finger 5. Thus, the finger 5 is movable around the axis A5, and the tooth 51 retracts under the actuation of the finger 21. Therefore, the finger 21 does not drive the moving part 4 in rotation around the axis A4. The moving part 4 is ultimately driven by a single angular step around the axis A4, through the interaction of the finger 11 and a tooth of the gear set 41 at a first angle β1 around the axis A1. The star 9, for its part, is driven by an angular step around the axis A9, under the actuation of the finger 23.

[0065] On the figure 14The follower 6 is positioned here by the cam 7, specifically by the pin 61 and the groove 71, such that the flank 62 of the follower is beyond the reach of the surface 52 of the finger 5. Thus, the finger 5 is movable around the axis A5, and the tooth 51 retracts under the actuation of the finger 21. Therefore, the finger 21 does not drive the moving part 4 in rotation around the axis A4. The moving part 4 is ultimately driven by a single angular step around the axis A4, through the interaction of the finger 11 and a tooth of the gear set 41 at a first angle β1 around the axis A1. The star 9, for its part, is driven by an angular step around the axis A9, under the actuation of the finger 23.

[0066] The same events also occurred during the transition of the display from March 28 to March 29 and during the transition of the display from March 29 to March 30. Operational at the end of April

[0067] THE Figures 15 to 16illustrate the operation of the calendar system during the transition from the date to the end of April. During this phase, mobile 4 makes two jumps or angular steps.

[0068] There figure 15 illustrates the calendar system at midnight on April 30th. The follower 6 is positioned here by the cam 7, in particular by the pin 61 and the groove 71, such that the flank 62 of the follower 6 is in contact with the surface 52 of the finger 5. Thus, when the finger 21 comes into contact with the tooth 51, this causes the mobile 4 to rotate around the axis A4, even though the finger 11 is out of reach of the teeth 41.

[0069] There figure 16This illustrates the calendar system once the moving part 4 has moved a first angular step around axis A4, after the finger 21 has rotated a third angle α3 around axis A2. In this configuration, finger 21 leaves contact with tooth 51 and finger 11 engages with one of the teeth of gear 41 so that it can in turn drive the moving part 4 a second angular step around axis A4. At this point, the star 9 is also driven by the action of finger 23.

[0070] During this phase of operation, finger 21 caused the date wheel 4 to move one step, and finger 11 caused the date wheel 4 to move one step. On April 30, just before midnight, the date wheel indicated "30," and on May 1, just after midnight, the date wheel indicated "1." The two drive steps of the date wheel 4 enabled the following two successive transitions: from the display of the date "30" to the display of the date "31", then, from the display of the date "31" to the display of the date "1", during an instant training.

[0071] At midnight on April 28, just before the jump of the moving part 4, the follower 6 is positioned by the cam 7, specifically by the pin 61 and the groove 71, such that the flank 62 of the follower is out of range of the surface 52 of the finger 5. Thus, the finger 5 is movable around the axis A5, and the tooth 51 retracts under the actuation of the finger 21. Therefore, the finger 21 does not drive the moving part 4 in rotation around the axis A4. The moving part 4 is ultimately driven by a single angular step around the axis A4, by the cooperation of the finger 11 and a tooth of the gear set 41 at a first angle β1 around the axis A1. The star 9, meanwhile, is driven by an angular step around the axis A9, under the actuation of the finger 23.

[0072] Similarly, at midnight on April 29, just before the jump of the moving part 4, the follower 6 is positioned by the cam 7, specifically by the pin 61 and the groove 71, such that the flank 62 of the follower is out of range of the surface 52 of the finger 5. Thus, the finger 5 is movable around the axis A5, and the tooth 51 retracts under the actuation of the finger 21. Therefore, the finger 21 does not drive the moving part 4 in rotation around the axis A4. The moving part 4 is ultimately driven by a single angular step around the axis A4, through the cooperation of the finger 11 and a tooth of the gear set 41 at a first angle β1 around the axis A1. The star 9, meanwhile, is driven by an angular step around the axis A9, under the actuation of the finger 23.

[0073] Thus, we note that the activation system 6, 7 is preferably arranged so that the single action of the first driving finger 21 on the first tooth 51 causes, depending on the time of the activation of the first tooth 51 by the activation system 6, 7, a displacement of the date wheel 4 of n steps, with n an integer taking any value between 1 and N, N being an integer such that N>1, in particular N=2 or N=3.

[0074] Thus, we note that the activation system 6, 7 is preferably arranged so that at least one first position of the month cam 7 defines a first position of the follower 6 allowing the retraction of the first tooth 51 and that at least one second position of the month cam 7 defines a second position of the follower 6 prohibiting the retraction of the first tooth 51.

[0075] As previously mentioned, the invention relates to a method for operating the clock calendar system or clock movement or timepiece, the method comprising the following steps: an activation of the first tooth 51, a single action of the first training finger 21 on the first tooth 51 capable of causing a displacement of the mobile of the dates 4 of an amplitude of at most N steps, N being an integer such that N>1, in particular N=2 or N=3.

[0076] Advantageously, the single action of the first driving finger 21 on the first tooth 51 causes, depending on the time of activation of the first tooth 51 by the activation system 6, 7, a displacement of the date wheel 4 of n steps, with n an integer taking any value between 1 and N.

[0077] Thus, the invention also relates to a method of operating the clock calendar system or clock movement or timepiece, the method comprising the following steps: an activation of the first tooth 51, a single action of the first driving finger 21 on the first tooth 51 causing a displacement of the date wheel 4 according to the instant of the activation of the first tooth 51 by the activation system 6, 7 of n steps, with n an integer taking any value between 1 and N, N being an integer such that N>1, in particular N=2 or N=3.

[0078] Whatever the process mentioned above, it is noted that, preferably, in accordance with what has been described previously, when the first tooth 51 is activated (by piloting the activation system 6, 7), the first finger 21 exerts on the first tooth 51 a mechanical action driving the date wheel 4.

[0079] Alternatively or complementarily, whatever the process mentioned above, it is noted that, preferably, when the first tooth 51 is deactivated (by the control of the activation system 6, 7), the first finger 21 exerts on the first tooth 51 a mechanical action of retracting the first tooth 51 without driving the date wheel 4.

[0080] It is therefore entirely possible to adapt the activation system 6, 7 to implement an annual calendar system. In this case, the activation system controls the activation of finger 51 each month as if it were a 30-day month or a 31-day month, without modifying the drive mechanism components. To achieve this, cam 7, in particular groove 71, could be modified.

[0081] The month cam 7 is driven in rotation around an axis A7 during certain date transitions. To achieve this, the teeth 72 of the cam 7 are likely to be driven periodically by teeth of the teeth 42 of the moving part 4, via the pinion 8 interposed between the moving part 4 and the cam 7.

[0082] According to another aspect of the invention, the embodiment of the timepiece 400 or the time movement 300 or the calendar system 200 comprises a movement transmission system 90 comprising: the driving mobile 4 pivoted about the first axis A4 and comprising the driving teeth 42 distributed on a curved profile 43, in particular a circular profile 43, the driven mobile 7 pivoted about the second axis A7 and comprising the driven teeth 72, the intermediate pinion 8 pivoted about the third axis A8 and comprising a tooth 81 driven by the driving teeth 42 and driving the driven teeth 72.

[0083] Preferably, the curved profile 43 is centered on the axis A4 and defines at least partially the outer contour of the leading mobile 4.

[0084] The driving teeth 42, the curved profile 43, the driven teeth 72 and the teeth 81 are arranged on the same level or in the same plane.

[0085] The driving wheel 4, the driven wheel 7 and the intermediate pinion 8 are arranged so that the driving wheel 4 drives the driven wheel 7 in motion, via the intermediate pinion 8, by 1 / m steps during at least some steps of the driving wheel 4, with m a real number greater than 1 and preferably between 2 and 20.

[0086] The driving mobile 4, the driven mobile 7 and the intermediate pinion 8 are arranged so that the driving mobile 4 can define an angular position with least backlash of the driven mobile 7 via the pinion 8 while the driving mobile 4 is in a given angular position, in particular via the curved profile 43.

[0087] As depicted on the figure 21 , the pinion 8 has teeth 81 which have the particularity of extending on a single level or plane P8, and on the other hand of including teeth 81i which are not equidistant relative to the axis A8 of said pinion.

[0088] In particular, the 81 dentition has the particularity of including distinct first and second steps p1, p2.

[0089] The concept of pitch p between two consecutive teeth can be equated here with the concept of distance d between the teeth, measured along a direction approximately orthoradial to axis A8, regardless of the number of teeth and / or the module of the pinion teeth. This distance can be measured at the head 811i of each tooth.

[0090] Thus, more precisely, the distance d here corresponds to the length of an arc centered on the axis A8, which connects the heads 811i of two consecutive teeth.

[0091] Alternatively, the notion of pitch p between two consecutive teeth can be likened here to the notion of angle α formed by two planes P81i perpendicular to plane P8, which respectively cross two consecutive teeth by passing through axis A8 and through the respective head 811i of each of these teeth.

[0092] Naturally, d and α are correlated, with d~ α×r where r represents the pinion head radius, and α is expressed in radians.

[0093] Practically speaking, as is most particularly visible on the figure 21Each tooth 81i can form a tooth 81a positioned between two teeth 81b and 81c. More specifically, teeth 81b and 81c are positioned on either side of tooth 81a, respectively in a first direction s1 and a second direction s2 as viewed from tooth 81a. Tooth 81b is positioned at a first distance d1 from tooth 81a, while tooth 81c is positioned at a second distance d2 from tooth 81a. The first and second distances d1, d2 are different, and the first and second directions s1, s2 are opposite.

[0094] By convention, d2>d1 on the figure 21 Preferably, d2>1.5×d1, or even d2>1.6×d1, or even d2>1.7×d1.

[0095] By convention, direction s1 corresponds to the trigonometric direction and direction s2 to the clockwise direction on the same figure 21 . Angles α1, α2 can also be oriented angles, with α1 being considered positive and α2 being considered negative.

[0096] Thus, practically, tooth 81b and tooth 81a are separated by a first oriented angle α1 around the axis A8, and tooth 81c and tooth 81a are separated by a second oriented angle α2 around the axis A8, α1 and α2 being different and of opposite signs.

[0097] On the figure 21 , |α2|>|α1|. Preferably, |α2|>1.5×|α1|, or even |α2|>1.6×|α1|, or even |α2|>1.7×|α1|.

[0098] More generally, tooth 81b is adjacent to tooth 81a at a distance of a first step p1 in a first direction s1, and tooth 81c is adjacent to tooth 81a at a distance of a second step p2 in a second direction s2.

[0099] Thus, the dentition 81 comprises pairs of teeth. Two teeth of the same pair are separated by a distance of one first step p1 and two teeth of two distinct pairs are separated by a distance of one second step p2.

[0100] Preferably, each tooth 81i has the same head radius r.

[0101] Advantageously, the teeth 81i are asymmetrical with respect to their plane P81i. Thus, each tooth 81i comprises a first flank 812i and a second flank 813i that are different. Such a tooth configuration allows for the optimization of the geometries of each flank with respect to their respective functions.

[0102] In particular, each tooth 81i of the gear set 81 comprises first flanks 812i which allow it, on the one hand, to be driven by the teeth 42i of the gear set 42 of the moving part 4, and on the other hand, to drive, at least partially, the teeth of the gear set 72i of the cam 7. Preferably, the teeth 42i are each surrounded by two cutouts 42j, 42k and distributed along the curved profile 43. Depending on the configuration of the cam 7, the first flanks 812i also allow indexing of said cam 7 into position, namely angular locking with less play of said cam 7. The first flanks 812i are specifically shaped to optimize the driving of the pinion 8 under the effect of the drive of the moving part 4. In particular, the geometry of the flanks 812i can be specifically optimized with regard to this aspect.

[0103] The toothing 81 includes second flanks 813i which allow on the one hand to guide the teeth 72i of the toothing 72 of the cam 7, and on the other hand to allow its indexing in position opposite the mobile 4, namely its angular locking with less play vis-à-vis the mobile 4, in particular by cooperation with portions 43 of the mobile 4, in particular cylindrical portions 43 defining at least partially the outer periphery of the mobile 4.

[0104] The toothing 81 of the pinion 8 thus formed, the cam of the months 7 can also have a toothing 72 comprising teeth 72i separated by slots 73i whose format is a consequence of the pitch p2 of the toothing 81. Preferably, the teeth 72i are each surrounded by two second cutouts 72j, 72k.

[0105] The flanks 812i and 813i thus constitute means of driving and / or locking the elements 4 and 7 arranged on the same level. Such a tooth configuration 81 makes it possible to offer a pinion formed on a single level, and therefore a fortiori to arrange the teeth 42 and 72 on a single level. This has the advantage of enabling the implementation of a particularly slim 200-series timing system. Furthermore, thanks to the asymmetrical design of the teeth 81i, the flanks 812i and 813i can be optimized for their respective functions. In particular, the engagement of the pinion 8 and / or the cam 7 can be maximized while maintaining adequate locking of the pinion 8 and / or the cam 7 with minimal backlash, specifically by preventing any risk of bridging between these components.

[0106] Furthermore, the driving gear 4, the driven gear 7 and the intermediate pinion 8 are arranged such that: one or more teeth 42i of the driving teeth 42 cooperate exclusively with internal flanks 812i of tooth pairs of pinion 8, and external flanks 813i of tooth pairs of pinion 8 cooperate with flanks of the second cutouts 72j, 72k of the driven teeth 72, and the curved profile 43 cooperates exclusively with the external flanks 813i.

[0107] In the embodiment illustrated in the figures, the gear set 81 comprises eight teeth. Visually, the gear set 81 comprises four pairs of teeth, each pair separated by a pitch p2, and the teeth of each pair separated by a pitch p1. The teeth of each pair are symmetrical with respect to a plane P81 perpendicular to plane P8 and passing through axis A8. Furthermore, the gear set 81 exhibits rotational symmetry of order 4 about axis A8. In particular, the pairs of teeth 81i define a rotational symmetry of order 4 about axis A8. The flanks 812i are symmetrical with respect to plane P81. Similarly, the flanks 813i are symmetrical with respect to plane P81.

[0108] Such a pinion 8 allows, for example, the month cam 7 to be driven through seven angular steps of the date wheel 4, in this case from the 26th of a given month to the 2nd of the following month. Figures 17 and 18These are detailed views illustrating elements 4, 7, and 8 of the calendar system on the 26th and 27th of February, respectively. figures 7 to 12 illustrate the states of the calendar system from the 28th of a month of February until the 2nd of March.

[0109] Actuating the month cam 7 before the 28th of a given month is particularly advantageous for implementing a semi-perpetual or perpetual calendar system. Indeed, such a sequence allows the cam follower 6 to be positioned so as to lock the tooth 51 relative to the date wheel 4 from the 28th of a February or the 29th of a February in a leap year.

[0110] More specifically, in a semi-perpetual calendar system, the month cam 7 is always activated before the 28th of a given month. In the calendar system embodiment illustrated in the figures, the month cam 7 is activated from the transition from the 26th to the 27th of a given month. Figures 19 and 20 illustrate respectively the configuration of the cam 7 and the follower 6 on the 27th and 28th of a month of February. On February 27th, the pin 61 of the follower 6 is located in the groove 71 of the cam 7 at the level of a first radius R1' centered on the axis A7, while on February 28th, this same pin is located in the groove 71 of the cam 7 at the level of a second radius R2' centered on the same axis, which positions the follower 6 so as to lock the tooth 51 relative to the date wheel 4, and thus allows the movement of the date wheel 4 over three additional steps under the effect of the finger 21, and therefore the transition of the date from February 28th to March 1st.

[0111] Thus, at the end of February in a non-leap year, tooth 51 is activated on February 28th to allow the date wheel 4 to move three additional steps under the action of finger 21, and therefore the date to change from February 28th to March 1st. At the end of a thirty-day month, tooth 51 is activated on the 30th of the given month to allow the date wheel 4 to move one additional step under the action of finger 21. Thus, the single action of the first driving finger 21 on the first tooth 51 results, depending on the moment of activation of the first tooth 51 by the activation system 6, 7, in a movement of the date wheel 4 by one or more additional steps. In addition, in a perpetual calendar, at the end of a February month of a leap year, tooth 51 can be activated on February 29 so as to allow the movement of the date wheel 4 over two additional steps under the effect of finger 21.

[0112] Depending on the shape and arrangement of the teeth 42, 81, and 72, the angular displacement of the month cam 7, due to the angular displacement of the date wheel 4, can vary from one date change to another. Specifically, between the 26th of a given month and the 2nd of the following month, it may be possible to prevent the month cam from moving during a date change. This is particularly true of the calendar system embodiment illustrated in the figures, where the month cam 7 is not moved when moving from the 28th to the 29th of a given month, as shown in the figures. figures 7, 8 .

[0113] Preferably, the month cam 7 also has the specific feature of being activated after the first date of each month, preferably until the second date of each month, so as to properly position the possible display supported by the month cam in relation to the openings of the dial.

[0114] Naturally, the number of teeth on the gear 81 can vary. As an alternative to the embodiment described (comprising 4 pairs of teeth), the gear 81 of the pinion 8 can, for example, comprise 10 teeth, in particular 5 pairs of teeth.

[0115] Moreover, like the date mobile 4 which can be considered in general as any mobile and not necessarily as a disc, the cam 7 can also be considered more generally as a mobile, so as to take into account the case in which the mobile 7 is presented more simply in the form of a wheel of months.

[0116] In an alternative embodiment, one could also imagine a date wheel 4 comprising an internal toothing 42 and a month wheel 7 comprising an external toothing 72. The functions of the pinion 8 would then remain unchanged.

[0117] Preferably: the mobile led 7 is a month mobile, specifically a month cam and / or a month display mobile, or the mobile led 4 is a date mobile.

[0118] Depending on the transmission system configurations: the led mobile 7 surrounds the leading mobile 4, or the leading mobile 4 surrounds the led mobile 7.

[0119] Preferably, the driven mobile 7 is a month cam arranged to control the activation of the first drive tooth 51 of the driving mobile constituting a date mobile 4, the first tooth 51 being mounted movable on the date mobile 4 between a deactivated or retracted position and an activated or drive position.

[0120] According to the solutions described, the drive device 100 advantageously comprises first and second drive wheels 1, 2 kinematically linked to each other, each equipped respectively with a first finger and a second finger whose respective axes, in particular their respective axes of rotation, are distinct and preferably fixed relative to a frame. Furthermore, this drive device is further enhanced by the inclusion, on the second wheel, of a second finger designed to actuate a tooth mounted movably on a date wheel, thereby enabling at least one additional jump of the date wheel at the end of a month of thirty days or less.

[0121] By incorporating a movable tooth onto a date wheel, the programming of an annual, semi-perpetual, or perpetual cycle can be controlled via a month programming cam that is independent of the drive mechanism. This significantly simplifies the drive mechanism, making it more efficient and compact. This solution advantageously allows for the implementation of an instantaneous jump drive compatible with annual, semi-perpetual, or perpetual calendar systems. Furthermore, its compact size also enables the drive of other calendar indications, such as the day of the week.

[0122] Such a calendar system has the advantage of being able to be implemented independently of any return or indexing spring, by means of a desmodromic activation system comprising a cam and a cam follower which govern the programming of an annual, semi-perpetual, or perpetual cycle.

[0123] The calendar system preferably features an instantaneous jump drive with two separate drive elements. This drive configuration allows for a particularly versatile calendar system, notably enabling the easy implementation of an annual or semi-perpetual calendar without adding or substantially modifying existing components. Furthermore, this drive configuration minimizes energy losses in the oscillator, particularly when implementing an instantaneous jump semi-perpetual or perpetual calendar.

[0124] Throughout this request, "step" refers to the angular gap separating two stable (or indexed) and immediately adjacent positions of a moving object.

[0125] By way of exception to the preceding paragraph, with regard to the mobile led 7 or the cam of the months 7, by "step" is meant an angle of 30°, namely an angle of 360° / 12, 12 being the number of months in a year.

Claims

1. Timepiece calendar system (200), the system comprising: - a date mobile (4) which is displaceable step by step relative to a frame (199); - a first drive finger (21) for driving the date mobile (4); - a first tooth (51) for driving the date mobile (4), the first tooth (51) being mounted on the date mobile (4) so as to be displaceable between a deactivated, or retracted, position and an activated, or drive, position; - an activation system (6, 7) for activating the first tooth (51); the first drive finger (21) and the first tooth (51) being arranged such that a single action of the first drive finger (21) on the first tooth (51) can displace the date mobile (4) through N steps, N being an integer such that N>1, notably N=2 or N=3, the calendar system being characterized in that it comprises a second drive finger (11) for driving the date mobile (4).

2. Timepiece calendar system (200) according to the preceding claim, wherein the activation system (6, 7) is arranged such that the single action of the first drive finger (21) on the first tooth (51) displaces the date mobile (4) through n steps, with n being an integer of any value between 1 and N, depending on the moment at which the first tooth (51) is activated by the activation system (6, 7).

3. Timepiece calendar system (200) according to either of the preceding claims, wherein the activation system (6, 7) is a desmodromic system (6, 7) comprising a month cam (7) and a cam follower (6), the desmodromic system being arranged such that at least a first position of the month cam (7) defines a first position of the follower (6) allowing the retraction of the first tooth (51), and that at least a second position of the month cam (7) defines a second position of the follower (6) preventing the retraction of the first tooth (51).

4. Timepiece calendar system (200) according to the preceding claim, wherein the month cam (7) and the date mobile (4) are coaxial.

5. Timepiece calendar system (200) according to one of the preceding claims, wherein the second drive finger (11) for driving the date mobile (4) is arranged so as to interact with a toothset (41) of the date mobile (4), in particular a toothset (41) having 31 teeth.

6. Timepiece calendar system (200) according to the preceding claim, wherein the first drive finger (21) forms part of a first drive mobile (2), and wherein the second drive finger (11) forms part of a second drive mobile (1), the first drive mobile (2) and the second drive mobile (1) comprising, preferably respectively, a first axis (A2) of rotation and a second axis (A1) of rotation which are separate.

7. Timepiece calendar system (200) according to the preceding claim, wherein the first drive mobile (2) and the second drive mobile (1) are kinematically connected to one another by a third drive mobile (3).

8. Timepiece calendar system (200) according to one of the preceding claims, wherein it comprises an instantaneous drive device (92, 96, 97), notably an instantaneous drive device (92, 96, 97) comprising a spring-lever (97) and a calendar cam (96), in particular a calendar cam (96) arranged at the third drive mobile (3).

9. Timepiece calendar system (200) according to one of the preceding claims, wherein the system comprises a device (98) for holding the date mobile (4) in position and a device (93) for minimizing or cancelling the holding torque for holding the date mobile (4) in position, notably a device (93) comprising a cam (95) arranged at the second drive mobile (1).

10. Timepiece calendar system (200) according to claim 6 and one of the preceding claims, wherein the first drive mobile (2) comprises a third finger (23) for driving a day mobile.

11. Timepiece calendar system (200) according to one of the preceding claims, wherein the system comprises a kinematic connection element (8) arranged such that the date mobile (4) moves a month cam (7) forming part of the activation system (6, 7) of the first tooth (51) through 1 / m steps for at least some steps taken by the date mobile (4), with m being a real number greater than 1 and preferably between 2 and 20.

12. Timepiece calendar system (200) according to one of the preceding claims, wherein the system comprises a kinematic connection element (8) arranged such that the date mobile (4) moves a month cam (7) forming part of the activation system (6, 7) such that the month cam (7) is displaced each month before or during the jump from the day of the month "27" to the day of the month "28", for example during the jump from the day of the month "26" to the day of the month "27".

13. Timepiece movement (300) comprising a system (200) according to one of the preceding claims.

14. Timepiece movement (400), in particular wristwatch, comprising a system (200) according to one of Claims 1 to 12 and / or a timepiece movement (300) according to Claim 13.

15. Method for operating a timepiece calendar system according to one of Claims 1 to 12 or a timepiece movement according to Claim 13 or a timepiece according to Claim 14, the method comprising the following steps: - activating the first tooth (51), - a single action of the first drive finger (21) on the first tooth (51) being able to displace the date mobile (4) through an amplitude of at most N steps, N being an integer such that N>1, notably N=2 or N=3.

16. Operating method according to the preceding claim, wherein the single action of the first drive finger (21) on the first tooth (51) displaces the date mobile (4) through n steps, with n being an integer of any value between 1 and N, depending on the moment at which the first tooth (51) is activated by the activation system (6, 7).

17. Operating method according to Claim 15 or 16, wherein, when the first tooth (51) is activated, the first finger (21) subjects the first tooth (51) to a mechanical action for driving the date mobile (4), and / or wherein, when the first tooth is deactivated, the first finger (21) subjects the first tooth (51) to a mechanical action for retracting the first tooth (51) without driving the date mobile (4).

Images