US-12625470-B2 - Timepiece calendar system

US12625470B2US 12625470 B2US12625470 B2US 12625470B2US-12625470-B2

Abstract

The timepiece calendar system ( 200 ) includes a date mobile ( 4 ) 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 ) displaces the date mobile ( 4 ) through n steps, with n being an integer of any value between 1 and N, N being an integer with N>1, depending on the moment when the first tooth ( 51 ) is activated by the activation system ( 6, 7 ).

Inventors

Christian Fleury
Frédéric Jolliet

Assignees

ROLEX SA

Dates

Publication Date: 20260512
Application Date: 20221125
Priority Date: 20211130

Claims (20)

1 . A timepiece calendar system, the system comprising: a date mobile which is displaceable step by step relative to a frame; a first drive finger for driving the date mobile; a first tooth for driving the date mobile, the first tooth being mounted on the date mobile so as to be displaceable between a deactivated, or retracted, position and an activated, or drive, position; an activation system for activating the first tooth; the first drive finger and the first tooth being arranged so that a single action of the first drive finger on the first tooth displaces the date mobile through n step(s), wherein n is an integer of any value in a range of from 1 to N, N is an integer and N>1, wherein the single action is repeated so that, depending on a moment at which the first tooth is activated by the activation system, n takes each value in the range of from 1 to N.
2 . The timepiece calendar system according to claim 1 , wherein the activation system is a desmodromic system comprising a month cam and a cam follower, the desmodromic system being arranged so that at least a first position of the month cam defines a first position of the follower allowing retraction of the first tooth, and so that at least a second position of the month cam defines a second position of the follower preventing the retraction of the first tooth.
3 . The timepiece calendar system according to claim 2 , wherein the month cam and the date mobile are coaxial.
4 . The timepiece calendar system according to claim 1 , wherein it comprises a second drive finger for driving the date mobile.
5 . The timepiece calendar system according to claim 4 , wherein the second drive finger is arranged so as to interact with a toothset of the date mobile.
6 . The timepiece calendar system according to claim 4 , wherein the first drive finger forms part of a first drive mobile, and wherein the second drive finger forms part of a second drive mobile, the first drive mobile and the second drive mobile comprising a first axis of rotation and a second axis of rotation which are separate.
7 . The timepiece calendar system according to claim 6 , wherein the first drive finger has a first head radius and the second drive finger has a second head radius, the first and second head radii being different.
8 . The timepiece calendar system according to claim 7 , wherein the first head radius is greater than the second head radius.
9 . The timepiece calendar system according to claim 6 , wherein the first axis is disposed on a first circle centered on an axis of the date mobile and is at a first radius, and wherein the second axis is disposed on a second circle centered on the axis of the date mobile and is at a second radius.
10 . The timepiece calendar system according to claim 9 , wherein the first drive mobile and the second drive mobile are kinematically connected to one another by a third drive mobile.
11 . The timepiece calendar system according to claim 9 , wherein the first radius is less than the second radius, the toothset of the date mobile being an inner toothset and the first tooth being oriented inwards.
12 . The timepiece calendar system according to claim 1 , wherein the system comprises an instantaneous drive device comprising a spring-lever and a calendar cam.
13 . The timepiece calendar system according to claim 12 , wherein the calendar cam is arranged at a third drive mobile.
14 . The timepiece calendar system according to claim 1 , wherein the system comprises a device for holding the date mobile in position and a device for minimizing or cancelling the holding torque for holding the date mobile in position.
15 . The timepiece calendar system according to claim 14 , wherein the device for minimizing or cancelling the holding torque for holding the date mobile in position comprises a cam arranged at a second drive mobile.
16 . The timepiece calendar system according to claim 1 , wherein the first drive mobile comprises a third finger for driving a day mobile.
17 . A timepiece movement comprising the timepiece calendar system according to claim 1 .
18 . A timepiece comprising the timepiece movement according to claim 17 .
19 . A method for operating the timepiece calendar system according to claim 1 , the method comprising: activating the first tooth, wherein a single action of the first drive finger on the first tooth causes a displacement of the date mobile through n steps, depending on the moment at which the first tooth is activated by the activation system.
20 . The method according to claim 19 , wherein, when the first tooth is activated, the first finger subjects the first tooth to a mechanical action for driving the date mobile, and/or wherein, when the first tooth is deactivated, the first finger subjects the first tooth to a mechanical action for retracting the first tooth without driving the date mobile.

Description

This application claims priority of European patent application No. EP21211473.0 filed Nov. 30, 2021, the content of which is hereby incorporated by reference herein in its entirety. BACKGROUND ART The invention relates to a timepiece calendar system. The invention also relates to a timepiece movement comprising such a timepiece calendar system. The invention further relates to a timepiece comprising such a timepiece movement or such a timepiece calendar system. The invention still further relates to a method for operating such a timepiece calendar system or such a timepiece movement or such a timepiece. The invention lastly relates to a transmission system with which such a timepiece calendar system or such a timepiece movement or such a timepiece can be equipped. Document EP3567438 describes an embodiment of a calendar system, notably an annual calendar system, comprising a drive device provided with a single and unique drive mobile. This drive mobile comprises a first finger provided to actuate one of the thirty-one teeth of a date disc in order to enable a first jump of said date disc and thus make it possible to change the date irrespective of the day of the month, and also an additional finger, angularly offset with respect to the first finger, provided to actuate a tooth of a finger mounted so as to be able to move on the date disc in order to enable a supplementary jump of said date disc at the end of a month having thirty days or fewer. Advantageously, the drive device comprises a calendar cam and an elastic lever. The interaction of the cam and the lever enables an instantaneous rotation of the drive mobile, thereby making it possible to instantaneously change the date irrespective of the number of jumps performed by the date disc. Document CH680630 likewise discloses a drive device provided with a single and unique drive mobile, notably within a perpetual calendar system. This solution is hardly compatible with the implementation of an instantaneous-jump drive device. This is because the displacement performed by the drive mobile to enable the multiple jumps of the date wheel when a hypothetical elastic lever is being unwound should be maximized. The winding of the elastic lever, which should likewise be maximized, would thus be performed over a limited displacement of the drive mobile, this leading to abrupt variations in torque that are liable to cause resulting drops in amplitude at the oscillator, notably at a balance mobile-hairspring oscillator. It is thus necessary to define an instantaneous-jump drive device suitable for implementing notably a semi-perpetual or perpetual calendar, which makes it possible to reduce the energy losses at the oscillator as far as possible, whilst still being compact. Document EP0987609 describes a first drive mobile provided with an axis of rotation which is fixed relative to a frame, and a second drive mobile provided with an axis of rotation which is displaceable relative to the same frame, but the drive finger of the second mobile is provided to drive a tooth fixed to a date disc. In this design, the second mobile is mounted on a lever that can be displaced relative to the frame counter to a return spring generating a superfluous consumption of energy, which is hardly compatible with the implementation of an instantaneous-jump drive device. Document CH710109 describes a calendar system comprising a first drive mobile provided with an axis of rotation which is fixed relative to a frame, and a second drive mobile provided with an axis of rotation which is fixed relative to the same frame, but the drive finger of the second mobile is provided to drive an additional tooth fixed to a date wheel. In order to implement the calendar system according to document CH710109, the finger of the second mobile is mounted so as to be displaceable counter to a month-programming cam disposed coaxially with the second mobile, under the effect of a return spring. On the one hand, this return spring leads to a superfluous consumption of energy and causes torque fluctuations throughout a day, this being hardly compatible with the implementation of an instantaneous-jump drive device. On the other hand, the month-programming cam is particularly bulky, this leaving very little area available for the installation of a calendar cam and an elastic lever within the drive device. Furthermore, the installation of a month-programming cam disposed coaxially with the second mobile at least partially dictates the positioning of the axis of the second mobile relative to the frame, this possibly being a limiting factor for optimizing the drive of the date wheel under the action of the drive finger of the second mobile. Lastly, every day this finger performs a complete rotation around the month-programming cam, this possibly leading to premature wear of the drive device, all the more so if the second finger is elastically returned against the cam under the effect of a return spring. SUMMARY OF