Patent Application
20160202664
The invention relates to a device for driving a mobile of a calendar mechanism. It relates also to a mechanism comprising such a device. It also relates to a horological movement comprising such a device or such a mechanism. It finally relates to a timepiece, notably a wristwatch, comprising such a device, such a mechanism or such a movement.
The annual calendars known from the prior art are traditionally equipped with one or two calendar driving mobiles which are provided to cooperate with a cam or an auxiliary months wheel. This element carries the indication of the months and drives the double date jump mechanism at the end of each short month through possible additional springs and levers. Such a construction can lead to a particularly difficult sequencing of operation. While the installation of a calendar driving mobile accompanied by an energy accumulator can possibly make it possible to design a calendar with instantaneous jump for the transition from the 31-day months to the next month, the double date jump at the end of the 30-day months can be problematical, on the one hand, because of the sequencing of operation of two distinct kinematic chains driving the date indicator and, on the other hand, because of the energy increase that such a jump requires.
The patent application EP 0987609 describes an annual calendar mechanism provided with two kinematic chains driving the date indicator. A first calendar driving mobile allows, every day, a first jump of the date indicator. A second calendar driving mobile, called a correction mobile, allows for an additional jump of the date indicator at the end of a 30-day month. The latter is pivoted on a lever whose angular position is controlled by a months cam and return springs. Such a construction requires a significant number of parts, notably springs and levers, and consumes a lot of energy. Moreover, because of the sequencing of operation of such a mechanism, it is very difficult to obtain a perfectly instantaneous calendar date jump at the end of a short month.
The document U.S. Pat. No. 3,827,234 discloses an annual calendar with semi-dragging date jump, whose mechanism implements two distinct kinematic chains for driving the date indicator, that requires neither annual cam nor lever. A first conventional calendar driving mobile allows, every day, for a first jump of the date indicator. A second mobile allows for an additional jump of the date indicator at the end of a 30-day month. This mobile has teeth, the number and the arrangement of which are defined such that these teeth allow for the actuation of an additional tooth of the date indicator at the end of a short month, and thus allow, in cooperation with the conventional driving mobile, for a double jump of the date indicator. Such a mechanism presents the advantage of being simple compared to cam and lever devices, notably with respect to the mechanism disclosed in the document EP 0987609. The arrangement and the number of teeth of the second mobile make it possible in fact, with no other additional device, to distinguish short months from long months. However, the kinematic chain driving the second mobile requires an indexing device which is added to the traditional jumper of the date indicator, which is reflected in the installation of an additional spring provided to cooperate with a star which bears the teeth of the second mobile. It is therefore very difficult to achieve the implementation of an annual calendar with instantaneous date jump on the basis of such a mechanism, on the one hand because of the coordination required for a synchronized operation of the two chains driving the date indicator, and on the other hand because of the energy needed to allow for the instantaneous driving of two distinct driving mobiles, each mobile requiring indeed an energy accumulator that is dedicated to it.
The patent application EP 1666991 discloses an annual calendar mechanism with dragging date jump, which is provided with just one calendar driving mobile. The latter bears two driving fingers. The first finger allows, every day, for a first jump of the date indicator. The second finger is provided to drive the date indicator by an additional pitch, notably through a months mobile placed at the center of the movement. This mobile consists of two wheels fixed to one another. At the end of a thirty-day month, from the thirtieth to the “thirty-first”, the months mobile is driven by a first angular pitch through an additional tooth borne by the date indicator which is itself actuated by the first finger of the calendar driving mobile. From the “thirty-first” to the first of the next month, the months mobile is actuated by a second angular pitch by the second finger of the calendar mobile, and consequently drives the date indicator by an additional pitch through the additional tooth of the date indicator. Such sequencing is made possible by the fact that the calendar is purely dragging. The synchronized driving of each of the elements, notably of the date indicator and of the months mobile, would in effect lead to the immobilization of the device. Thus, it is not possible to achieve the implementation of an annual calendar with instantaneous date jump on the basis of such a mechanism.
The aim of the invention is to provide a device for driving a calendar mobile or a calendar organ that makes it possible to remedy the abovementioned drawbacks and improve the driving devices known from the prior art. In particular, the invention proposes a simple, compact, reliable and robust driving device, notably for the implementation of an annual calendar with instantaneous date jump.
A driving device according to the invention is defined as a device for driving a date mobile of a horological calendar mechanism, notably for driving a date disk of a horological calendar mechanism, the device comprising:
Different embodiments of the driving device are defined as follows:
A mechanism according to the invention is defined as a calendar mechanism comprising a device as above.
An embodiment of the mechanism is defined as of the instantaneous jump type.
A movement according to the invention is defined as comprising a device as above or a mechanism as above.
A timepiece according to the invention is defined as a timepiece, in particular a wristwatch, comprising a device as above or a mechanism as above or a movement as above.
An embodiment of a timepiece 130 is described hereafter with reference to
The calendar mechanism 110 comprises an embodiment of a driving device 100 according to the invention.
The embodiment of the driving device 100 is described in more detail hereafter with reference to
The driving device mainly comprises:
The first finger is suitable for cooperating with the first set of teeth, the second finger is suitable for cooperating with the second set of teeth, the first set of teeth is suitable for cooperating with the fourth set of teeth and the third set of teeth is suitable for cooperating with the fifth set of teeth.
Thus, the first finger is suitable for actuating the first set of teeth, notably by gear-meshing, the second finger is suitable for actuating the second set of teeth, notably by gear-meshing, the first set of teeth is suitable for actuating the fourth set of teeth, notably by gear-meshing, and the third set of teeth is suitable for actuating the fifth set of teeth, notably by gear-meshing.
Thus, it is possible to obtain a particularly simple driving device intended to drive the date indicator or date mobile. The simplicity of the architecture adds reliability and robustness to the device. This reliability and this robustness can be exploited to produce a calendar mechanism of the type with instantaneous jump.
Advantageously, the second and third sets of teeth are distinct, that is to say that the teeth of the second set of teeth cooperate neither with the fourth set of teeth nor with the fifth set of teeth and the teeth of the third set of teeth cooperate with the fifth set of teeth without cooperating with the fourth set of teeth.
Advantageously, the first finger 20a and the second finger 20b of the driving mobile 2 cannot be displaced relative to one another. Advantageously, the fourth set of teeth 30a and the fifth set of teeth 30b of the date indicator cannot be displaced relative to one another.
The programming mobile 1 has the particular feature of being disposed at the interface of the calendar driving mobile 2 and of the date indicator or date disk 3. The programming mobile makes it possible to recognize and distinguish the short months from the long months.
Advantageously, the first finger 20a, the first set of teeth 10a and the fourth set of teeth 30a are disposed on a first level, notably are disposed at the level of a first plane P1 as represented partially in
As represented in particular in
Advantageously, as represented by
Furthermore, the programming mobile can comprise a first abutment 1d, notably consisting of a portion of wall 1d of an opening 1i formed for example on the wheel 1a, and a second abutment 1e, notably a pin 1e. These first and second abutments cooperate to define, when they are in contact with one another, the predefined first position of the wheel 1a relative to the wheel 1b. The first and second abutments can be located respectively on the first and second wheels 1a, 1b or be located respectively on the second and first wheels 1a, 1b.
The spring 1c and the abutment 1d can be produced in one piece with the plate of the first wheel 1a. The pin 1e can be driven onto the plate of the second wheel 1b. The second wheel 1b can thus be angularly indexed relative to the first wheel 1a through the pin 1e which is pressed against the abutment 1d under the effect of the spring 1c.
The programming mobile 1 can comprise a third abutment 1g, notably a wall 1g of an opening, or of the abovementioned opening 1i, and a fourth abutment 1h, notably a surface 1h of the return element 1c, in particular a surface 1h of an end of the return element 1c. The third and fourth abutments can be located respectively on the first and second wheels 1a, 1b or be located respectively on the second and first wheels 1a, 1b.
The first and second wheels 1a and 1b of the driving mobile are both provided to be actuated, every day, by the calendar driving mobile 2. To this end, the driving mobile is provided, as seen previously, with two driving fingers 20a and 20b. These fingers are advantageously superposed or situated on two levels relative to the axis of rotation 12 of the driving mobile. These first and second fingers are each dedicated to driving the first and second sets of teeth 10a, 10b of the wheels 1a, 1b. Thus, preferentially, the first driving finger 20a can be disposed on the first level P1, and the second driving finger 20b can be disposed on the second level P2. The driving mobile also comprises a calendar wheel 5, performing one full rotation in 24 hours. This wheel 5 is linked to a drive-train 4 of the basic movement of the timepiece. The driving mobile 2 also comprises a cam 6 which is provided to cooperate with an energy accumulator, so that the driving fingers 20a and 20b can instantaneously drive the programming mobile 1 at the moment of midnight, that is to say that the first and second fingers arrive in a position of start of meshing with the sets of teeth of the wheels of the programming mobile, mesh with these sets of teeth, then leave a position of end of meshing with these sets of teeth, within a period typically less than a tenth of a second.
The cam 6 can be fixed to the first and second driving fingers 20a, 20b. A clutch between the calendar wheel 5 and the cam 6 (not represented) can be implemented through conventional means, such as, for example, an oblong cutout shaped to cooperate with a pin, or through a detent device such as that disclosed in the patent application EP 2428855A1, in particular in the passage of paragraphs 16 to 21.
The energy accumulator can comprise a lever 7 provided with a runner 7a which is pressed against the side of the cam 6 by a spring 8.
The programming mobile 1 is continually engaged with the date disk 3. Thus, an actuation of the driving mobile, notably an actuation of the driving mobile over one revolution, induces the rotation of the date disk 3, in particular over at least one angular pitch.
More particularly, the first set of teeth 10a of the first wheel 1a is continually engaged with the fourth set of teeth 30a of the date disk 3. This fourth set of teeth can be angularly indexed relative to the frame of the movement through a nose 9a of a jumper 9, as represented in
Advantageously, the jumper and the return element are shaped and arranged such that the resisting torque opposing the rotation of the first wheel and exerted by the jumper is greater than the resisting torque opposing the rotation of the second wheel and exerted by the return element, these torques being expressed about the same axis, notably about the axis 11 of rotation of the programming mobile.
In addition to the 31 teeth of the fourth set of teeth 30a, the date mobile is also provided with a fifth set of teeth 30b. This fifth set of teeth can notably comprise a single tooth. This fifth set of teeth can be superposed on the fourth set of teeth 30a as represented in
The tooth of the fifth set of teeth 30b is likely to be actuated by the third set of teeth 10c, on the 30th of a short month (that is to say of a 30-day month). Thus, the date disk 3 can be driven over two angular pitches.
In the embodiment described, the first set of teeth 10a of the first wheel 1a comprises twelve teeth which are all identical. The second set of teeth 10b of the second wheel 1b also comprises twelve teeth. The third set of teeth comprises four teeth which are arranged to actuate the date disk. These four teeth correspond to the four short months of the year, except for the month of February. These are distributed within the second set of teeth 10b such that one or other of these teeth is likely to be facing the tooth 30b on the 30th of a short month. The distribution of these teeth is explained later.
In the embodiment described, the teeth of the second set of teeth 10b and the teeth of the third set of teeth 10c are formed by common surfaces formed on a same part, notably common surfaces extending parallel to the axis of rotation of the programming mobile. Alternatively, the surfaces forming the teeth of the second and third sets of teeth can be discontinuous, that is to say that there can be a discontinuity between the second and third sets of teeth. The surfaces of the second and third sets of teeth can be formed simultaneously, for example by machining, cutting or forming. Alternatively, the second set of teeth can be formed on a first part and the third set of teeth can be formed on a second part. The first and second parts can then be assembled or fixed to one another to form the second wheel.
In another embodiment not represented, the first set of teeth can have a number of teeth which is a multiple of twelve, for example 24 or 36 teeth, and/or the second set of teeth can have a number of teeth which is a multiple of twelve, for example 24 or 36 teeth, and/or the third set of teeth can have a number of teeth which is a multiple of four, for example 8 or 12 teeth, and/or the fourth set of teeth can have thirty-one teeth and/or the fifth set of teeth can have one tooth.
The operation of the driving device is described in detail below.
A conventional date jump at the end of a 31-day month, for example at the end of the month of January, is described. The operation is the same on the other days of the month, except for the transition from the 30th of a short month to the first of the next month. Figure illustrates the annual calendar mechanism on January 30, just before the date jump from January 30 to 31.
Throughout the day, the wheel 5 drives the cam 6 and accumulates the energy needed for the instantaneous jump of the fingers 20a and 20b by arming the spring 8 via the profile of the cam 6 and of the lever 7. Just before the date transition, the runner 7a arrives at the summit of the profile of the cam 6.
The wheel 1b continues to pivot while the finger 20b drives the set of teeth 10b.
Thus, the conventional date jump is produced by the rotation by one angular pitch of the wheel 1a, which also involves the rotation by one angular pitch of the wheel 1b. Thus, every day at midnight, the mobile 1 turns by at least one angular pitch.
There follows a description hereafter of a date jump at the end of a 30-day month, for example at the end of the month of September.
The angular displacement of the date disk is a function of the angular displacement of the mobile 1, namely of the angular displacement of the wheels 1a and 1b relative to the frame of the movement. If a conventional date jump is produced by the rotation by one angular pitch of the wheel 1a, which also involves the rotation by an angular pitch of the wheel 1b, a double date jump at the end of a short month involves the rotation of the mobile 1, namely the rotation of the wheels 1a and 1b over two angular pitches of the mobile 1.
Over a full year, the mobile 1, the wheels 1a and 1b of which are provided with twelve teeth each, therefore perform thirty-one revolutions. Studies of the applicant have shown that it was possible to arrange teeth within the set of teeth 10c which are configured to actuate the tooth 30b of the disk 3 only on the 30th of a short month. There are four of these teeth for the wheels 1a and 1b of twelve teeth, and each is dedicated to a particular month without considering the month of February, as represented in
The table of
We note that:
the teeth 102b and 102c present themselves facing the tooth 30b at the end of the month of September,
the teeth 103b and 103c present themselves facing the tooth 30b at the end of the month of April,
the teeth 104b and 104c present themselves facing the tooth 30b at the end of the month of November,
the teeth 105b and 105c present themselves facing the tooth 30b at the end of the month of June,
the teeth 106b to 112b are each situated facing the tooth 30b at the end of a 31-day month. The latter cannot interact with the tooth 30b.
The studies of the applicant have shown that the principle is valid for any mobile 1 with wheels 1a, 1b that are provided with N teeth, where N is a multiple of 12. The set of teeth 1c is then provided with n teeth configured to actuate the tooth 30b, which are distributed in N/12 segment on the mobile 1, where N is a multiple of four with N/n=3.
Obviously, the month of February can be considered as a short month which is made up of 30 days, even if an adjustment will have to be made. In this case, the wheel 1b can then be provided with n′ teeth with n′=n+N/12.
In the embodiment previously described, the wheels 1a and 1b are provided with external sets of teeth 10a, 10b, 10c which are provided to cooperate with internal sets of teeth 30a, 30b of the date indicator 3. Alternatively, the sets of teeth 30a, 30b of the date disk 3 can take the form of external sets of teeth. Alternatively, the wheels 1a and 1b can be provided with internal sets of teeth 10a, 10b, 10c which can for example cooperate with external sets of teeth 30a, 30b of the date indicator 3, in particular for N=24 or N=36. In these alternative constructions, the mobile 3 can for example take the form of a disk or of a wheel to which is added a hand for displaying the date indication. Alternatively, the programming mobile 1 and/or the mobile 3 can be provided to actuate a mechanism for displaying a “large date”.
In the embodiment previously described, the profiles of the sets of teeth 10a, 10b and 10c are identical. Alternatively, the profiles can of course differ so as to be optimized with regard respectively to the elements 20a, 30a and 20b, 30b with which they cooperate.
In the embodiment previously described, the angular indexing element 9 is provided to cooperate with the set of teeth 30a of the date disk 3. Alternatively, this indexing element can be provided to cooperate with the wheel 1a. Such a conformation can be advantageous for a wheel 1a provided with an internal set of teeth 10a.
A display of the month can for example be implemented by a device comprising a month display disk linked kinematically to the date indicator. Thus, it is possible to implement a particularly simple embodiment of an annual calendar. The month display device can be as described in the patent applications EP2428856 and EP2624075.
The driving device according to the invention is particularly simple, like the device disclosed in the application EP1596261. The driving device according to the invention implements a reduced number of parts, and relies on just a single kinematic chain driving the date disk.
The driving device according to the invention also offers the advantage of being particularly compact, and of implementing a particularly simple date disk structure.
Preferably, in this document, in “programming mobile”, the term “mobile” means “an organ” or “a set of parts” or “a mechanism” that is movable or capable of moving, i.e. the parts of the set or of the mobile are advantageously mobile regarding one another and regarding other parts of the device. Preferably, in this document, in “programming mobile”, the term “mobile” does not mean a single wheel, plate or disk.
Preferably, the date mobile 3 is constituted by a single part.
Preferably, the driving mobile 2 is constituted by a single part.
| Number | Date | Country | Kind |
|---|---|---|---|
| 15150853.8 | Jan 2015 | EP | regional |
