A mechanism for displaying the number of weeks on a watch

Abstract

The invention relates to a mechanism for indicating the week number intended to be fitted to a watch movement, comprising a week star wheel (1) with 52 or 53 teeth and a week rocker (2) with a flexible finger (3) arranged to cooperate with the toothed arrangement of the week star wheel (1) when the rocker (2) is actuated by a drive movable device (5), one drive movable device (5) being driven one step per day by the watch movement and arranged to actuate the week rocker (2) once every seven days, when the last day of the week has passed and the first day of the week has arrived. According to the invention, the drive movable device is a drive star wheel (5) with seven teeth, six of which are so-called silent teeth (51) arranged so as not to actuate the week rocker (2), and one of these teeth is a drive tooth (52) arranged to actuate the week rocker (2) once a week, when the last day of the week has passed and the first day of the week has arrived.

Description

[Technical field]

[0001] The present invention relates to a mechanism for indicating the number of weeks intended to be adapted to a watch movement. [Background technology]

[0002] Typically, the mechanism for displaying the week number is arranged to drive a member displaying the week number by one step per week when the last day of the week has passed to the first day of the week. The display member is typically supported by a star wheel with 52 or 53 teeth, and therefore rotates 1 / 52 or 1 / 53 of a revolution each week. This angular movement is quite small, so it can be difficult to ensure that the function is performed accurately and precisely. Summary of the Invention [Problem to be solved by the invention]

[0003] The object of the present invention is therefore to provide a mechanism for indicating the number of weeks, intended to be adapted to a clock movement, which has a simple design but is able to ensure that its function is performed accurately and precisely. [Means for solving the problem]

[0004] The invention relates to a mechanism for indicating the number of weeks as claimed in claim 1, as well as to a timepiece movement as claimed in claim 12 and to a timepiece as claimed in claim 13.

[0005] The accompanying drawing shows, by way of example, a schematic embodiment of a mechanism for displaying the number of weeks according to the invention. [Brief description of the drawings]

[0006] [Figure 1] FIG. 13 illustrates a mechanism for displaying the week number according to the present invention during the last day of the week. [Diagram 2] FIG. 13 illustrates a mechanism for displaying the week number according to the present invention during the first day of the week. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] The mechanism for indicating the week number according to the invention is intended to be fitted into a watch movement. It comprises a weekly star wheel 1, which comprises 53 teeth, and which has an element for indicating the week number, preferably a hand (not shown). The element for indicating the week number can in particular cooperate with a scale containing 53 numbers, arranged to advance one step each week when the last day of the week has passed (moved over) to the first day of the following week.

[0008] Below, the last day of the week is considered to be Sunday and the first day of the week is considered to be Monday (this corresponds to the standard ISO 8601 for numbering the days of the week). Of course, other options are possible (for example, in some countries and cultures, such as the Hebrew calendar, the week starts on Sunday).

[0009] The weekly star wheel 1 is driven one step per week (1 / 53 of a revolution) by a weekly rocker 2 which pivots on a bridge or plate of the movement. The week rocker 2 comprises a flexible finger 3 arranged to cooperate with a tooth of the week star wheel 1 when the week rocker 2 pivots. The flexible finger 3 and the week rocker 2 are preferably made in one piece. A weekly jumper 13 ensures the positioning and the angular displacement of the week star wheel 1.

[0010] The weekly rocker 2 further comprises an active end 4, which in the illustrated embodiment is in the form of an inclined surface and which is intended to cooperate with a driving star wheel 5. Finally, the weekly rocker 2 is acted upon by a return spring 6.

[0011] The driving star wheel 5 is arranged to rotate once a week. To this end, the driving star wheel 5 can be connected to the movement of the watch by a suitable kinematic chain mechanism. The driving star wheel 5 is likewise arranged to cooperate with the active end 4 of the week rocker 2 once a week, when passing from Sunday to Monday, to cause said week rocker 2 to pivot against the action of its return spring 6, thereby pivoting the week star wheel 1 by one step via the flexible finger 3 of the rocker 2.

[0012] According to the invention, the drive star wheel 5 comprises seven teeth, six of which, called silent teeth 51, corresponding to the first to sixth days of the week (Monday to Saturday), are arranged so as not to cooperate with the active end 4 of the week rocker 2. Only the seventh tooth, called drive tooth 52, is arranged so as to cooperate with the active end 4 of the week rocker 2 to pivot said rocker 2 and thus advance the week star wheel 1 one step. Preferably, the six silent teeth 51 are of the same size (short enough not to get in the path of the active end 4 of the week rocker 2), while the drive tooth 52 is relatively long so as to be able to actuate the active end 4 of the week rocker 2.

[0013] As a result of this driving star wheel 5 and its particular shape, it is possible to easily and effectively manage very small angular movements of the week rocker 2 .

[0014] In the illustrated embodiment, the mechanism for displaying the week numbers cooperates with the mechanism for displaying the days of the week. In particular, the driving starwheel 5 is driven one step per day by a day-of-the-week starwheel 7, which includes seven teeth arranged to cooperate with both the silent teeth 51 and the driving teeth 52 of the driving starwheel 5.

[0015] The day star wheel 7 is driven one step per day when passing midnight or nearly midnight by a day finger 8 attached to a drive wheel 9, which is itself driven at a speed of one revolution per day by the movement of the clock. In the illustrated embodiment, the drive wheel 9 is connected to a wheel 10 on the hour of the movement via a setting wheel 11 and an intermediate wheel 12.

[0016] The day of the week star wheel 7 preferably has members (eg hands) for indicating the days of the week (not shown). The positioning and displacement of the day of the week star wheel 7 is ensured by jumpers 71 for the days of the week.

[0017] Preferably, the day finger 8 is arranged to be disengageable, i.e. driven by the drive wheel 9 to activate the day star wheel 7 when the drive wheel 9 rotates in a first direction (counterclockwise in the figure) and not to activate said day wheel 7 when the drive wheel 9 rotates in a second direction (reverse hand setting). Conventionally, to disengage such a day finger, it is pivotally mounted on the drive wheel and is subjected to the action of a return spring in cooperation with a pin driven into said drive wheel. Said return spring is fixed at one end to the drive wheel and at the other end cooperates with the day finger. The return spring is generally fixed to the wheel using two pins that surround a screw. However, fixing and guiding the return spring in the wheel is often problematic, since there is not always a sufficient axial retention of the pin and a thread with a sufficient number of turns to hold the screw, especially in the case of a thin wheel.

[0018] To solve this problem, in the illustrated embodiment, the day finger 8 is pivotally mounted on the drive wheel 9 and comprises a return strip 81 which is an integral part of or assembled with the day finger 8. The day finger 8 cooperates with a pin 91 fixed to the drive wheel 9 such that, when the drive wheel 9 rotates in a first direction, counterclockwise in the figure, the pin 91 abuts and drives the day finger 8, which cooperates with the day star wheel 7 to advance it step by step. The return strip 81 is shaped in such a way that when the drive wheel 9 rotates in the second direction (clockwise in the figure), the return strip 81 cooperates with the pin 91, so that the day finger 8, which has come into contact with a tooth of the day star wheel 7, pivots under the action of the return strip 81 without driving said day star wheel 7, remaining in a position in which it can resume driving said day star wheel 7, i.e. it returns to abutment against the pin 91 when the drive wheel 9 resumes rotation in the first direction.

[0019] Using the day finger 8 according to this embodiment simplifies the manufacture of the drive wheel 9 and makes it easier to attach the day finger 8 to the drive wheel 9 while ensuring the disengagement function of the day finger 8.

[0020] In the illustrated embodiment, the mechanism for displaying the week number further comprises a device for correcting the week number, which can be activated by the user, and also comprises a lever 14 for correcting the week, associated with a return spring 15, which activates the week rocker 2 and thus advances the week star wheel 1 stepwise at the user's request. The week rocker 2, in particular its active end 4, as well as the lever 14 for correcting the week, are arranged in such a way that they do not activate the drive star wheel 5 when the week rocker 2 is activated by the lever 14 for correcting the week.

[0021] Likewise, the mechanism for displaying the days of the week also preferably comprises a device for correcting the days of the week that can be actuated by the user and includes a corrector 16 for the days of the week controlled by a lever 17 and subjected to the action of a return spring 18. The day of the week corrector 16 is arranged to actuate the day of the week star wheel 7 stepwise at the request of the user. During such a correction of the day of the week, the rotation of the day of the week star wheel 7 does not drive the drive wheel 9 due to the day of the week finger 8 being disengaged (i.e. the day of the week finger 8 pivots against the action of its return strip 81 to a position in which it is no longer abutting against the pin 91). In the illustrated embodiment, the day of the week corrector 16 is likewise arranged to pivot the day of the week finger 8 out of the path of the day of the week star wheel 7 when, during a correction of the day of the week, the relative position of the day of the week finger 8 and the day of the week star wheel 7 can result in an abutment position between the finger 8 and the teeth of the star wheel 7. The day of the week corrector 16 therefore ensures optimal operation and makes it possible to avoid any abutment positions between the day of the week finger 8 and the teeth of the day of the week star wheel 7, which could lead to clogging or damage to the mechanism.

[0022] As a variant, the week star wheel 1 could include only 52 teeth, which would eliminate the need to correct the week count every year for 52 weeks, since 53 week years are extremely rare, and would only need to be corrected during the rare years that have 53 weeks.

[0023] In general, the mechanism for indicating the week number according to the invention comprises a week star wheel with 52 or 53 teeth and intended to hold an element for indicating the week number, a week rocker including a flexible finger arranged to cooperate with the teeth of the week star wheel, and a drive movable device arranged to be driven one step per day and to actuate the week rocker once every seven days when the last day of the week has passed (passed over) to the first day of the week, the flexible finger of said week rocker cooperating with the teeth of the week star wheel to advance it one step. According to the invention, the drive movable device is a drive star wheel with 7 teeth, of which 6 teeth are silent teeth arranged not to cooperate with the week rocker and of which one tooth is a drive tooth arranged to cooperate with said rocker once a week.

[0024] Preferably, the six silent tines are of the same length and the drive tine is longer than the silent tines.

[0025] Preferably, the flexible fingers of the weekly rocker are made in one piece with said rocker.

[0026] Preferably, the driving starwheel is driven by a day starwheel including seven teeth arranged to cooperate with silent teeth and with the driving teeth of the driving starwheel, and can be rotated by one step per day, securing its angular position under the action of a day jumper.

[0027] Other alternatives for driving the driving star wheel are possible, for example the driving star wheel can be driven by a finger arranged to complete one revolution per day. A seven-tooth star wheel fixedly and coaxially mounted on the driving star wheel and acted upon by a jumper can be arranged so as to ensure the angular position of the driving star wheel.

[0028] In this way, a mechanism for indicating the week number is provided which is of simple design and yet allows accurate and precise operation despite small angular movements of the week rocker and its flexible fingers, and which can be easily associated with conventional correction devices as well as with mechanisms for indicating the days of the week.

[0029] As a variant, the display mechanism as described above can be adapted to allow the display of other information, such as the month.

Claims

1. A mechanism for indicating the number of weeks intended to be fitted to a watch movement, comprising: A weekly star wheel (1) containing 52 or 53 teeth; a weekly rocker (2) including a flexible finger (3) arranged to cooperate with a tooth of the weekly star wheel (1) upon actuation of said rocker (2) by a drive movable device (5); Equipped with said one driving mobile (5) is driven by the movement of said clock one step per day and is arranged to actuate said week rocker (2) once every seven days, when passing from the last day of the week to the first day of the week; said drive movable device being a drive star wheel (5) comprising seven teeth, six of which are so-called silent teeth (51) arranged so as not to cooperate with said week rocker (2), and one of said teeth being a drive tooth (52) arranged to actuate said week rocker (2) once a week, when passing from the last day of the week to the first day of the week; A mechanism comprising:

2. a seven-tooth star wheel arranged to cooperate with said driving star wheel (5) to ensure its angular position under the action of a jumper, 2. The mechanism according to claim 1, characterized in that

3. the seven-tooth star wheel is fixedly and coaxially mounted to the driving star wheel (5); 3. The mechanism according to claim 2 .

4. a day of the week star wheel (7) which can be rotated by one step per day by the movement of the clock and which can be adjusted to the angular position of the day of the week by the action of a day of the week jumper (71); said day starwheel (7) comprising seven teeth arranged to cooperate with said silent teeth (51) and said driving teeth (52) of said driving starwheel (5) to drive said driving teeth (52) by one step per day; A mechanism according to any one of claims 1 to 3, characterized in that

5. the six silent teeth (51) of the driving star wheel (5) are of equal length and the driving teeth (52) are longer than the silent teeth (51); A mechanism according to any one of claims 1 to 4, characterized in that

6. the flexible finger (3) of said rocker (2) is made in one piece with said rocker (2); A mechanism according to any one of claims 1 to 5, characterized in that

7. the active end (4) of the week rocker (2) cooperating with the drive tooth (52) of the drive star wheel (5) has the shape of an inclined surface; A mechanism according to any one of claims 1 to 6, characterized in that

8. said day star wheel (7) being driven in one step per day by a day finger (8) supported by a drive wheel (9) which can be driven at a speed of one revolution per day by the movement of the clock; 5. The mechanism according to claim 4, characterized in that

9. said day finger (8) is arranged to be disengageable, i.e. to actuate said day star wheel (7) and move said day star wheel (7) forward one step when said drive wheel (9) rotates in a first direction, and to deactivate said day star wheel (7) when said drive wheel (9) rotates in a second direction; 9. The mechanism according to claim 8, characterized in that

10. said day finger (8) is arranged to cooperate with a pin (91) fixed to said drive wheel (9) so that, when said drive wheel (9) rotates in a first direction, said finger (8) abuts said pin (91) in a position capable of actuating said day star wheel (7); said day finger (8) comprises a return strip (81) which is in one piece with said day finger (8) or assembled therewith, said return strip (81) being shaped to cooperate with said pin (91) when said drive wheel (9) rotates in the second direction, so that said day finger (8), in contact with one tooth of said day star wheel (7), pivots under the action of said return strip (81) without driving said day star wheel (7) and remains in a position in which it can resume driving said day star wheel (7), i.e. in a position abutting said pin (91), when said drive wheel (9) resumes rotation in said first direction; 10. The mechanism according to claim 9.

11. Further comprising a member for indicating the number of the week supported by said week star wheel (1), A mechanism according to any one of claims 1 to 10, characterized in that

12. A clock movement comprising a mechanism for displaying the week number according to any one of claims 1 to 11.

13. A timepiece comprising a movement according to claim 12.

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