HK1235109B - Timepiece movement comprising a date correction mechanism - Google Patents

Description

Watch movement including date correction mechanism

Technical Field

The present invention relates to the field of mechanical horology, and more particularly to a watch movement comprising a control stem, a winding mechanism for winding the movement, a date display mechanism, and a time display mechanism.

Background Art

Many mechanical watches typically include a control stem located at 3 o'clock and capable of two positions: manual winding and time setting. These watches may also include a date display mechanism. Rapid date correction is performed using a push-button located on the watch case at a different position from the control stem, such as at 10 o'clock. However, this configuration requires an opening in the watch case for the push-button to pass through, which compromises the watch's seal and limits its decorative design options.

A solution to these problems is proposed in patent EP 2 707 778, and this solution comprises correcting the date by means of a control handle arranged to occupy the third position. However, in this mechanism, the correction element for the date is fixed and therefore permanently meshes with the day calendar ring (day date ring), and the correction of the date is carried out in two directions. If the user corrects the date at midnight, there is a risk of destroying the date drive arm. In addition, the wheel of the second wheel group carried by the second lever is permanently meshed with the pinion carried by the first lever, and the connection between these parts is ensured by their corresponding toothed rings. This structure requires the special cutting of these toothed rings to be arranged, so that they have concentric profiles to prevent any obstruction.

Summary of the Invention

The object of the present invention is to remedy the different drawbacks of the known mechanisms.

More precisely, one object of the present invention is to provide a timepiece movement that allows rapid correction of the date by means of a control stem and that does not require the push-button-related openings in the case that were previously necessary to perform this function.

The present invention also aims to provide a timepiece movement allowing a unidirectional correction of the date by means of a control stem.

To this end, the invention relates to a timepiece movement comprising a control stem, a winding mechanism for winding the movement, a date display mechanism and a time display mechanism.

According to the invention, the timepiece movement comprises a first lever carrying a first driving wheel which can be kinematically connected to a control stem, a second lever carrying a second wheel for time setting which is arranged to cooperate with a time display mechanism and can be kinematically connected to the first driving wheel, and a third lever carrying a date corrector mechanism which can be kinematically connected to the first driving wheel and to a date display mechanism, wherein the third lever is mounted so as to pivot on the second lever and is arranged to move between an engaged position in which the date corrector mechanism cooperates with the date display mechanism and a retracted position in which it is disengaged from the date display mechanism, and wherein the control stem and the first and second levers are arranged to occupy three positions:

a winding position in which the control stem is kinematically connected to a winding mechanism for winding the movement and is not kinematically connected to the first driving wheel;

a date correction position in which the control stem is kinematically connected to a first drive wheel and the first and second levers are positioned such that the first drive wheel is kinematically connected to the date correction mechanism and is not kinematically connected to the second wheel for time setting; and

a time-setting position in which the control stem is kinematically connected to the first driving wheel and the first and second levers are positioned such that the first driving wheel is kinematically connected to the second wheel for time setting and is not kinematically connected to the date corrector mechanism,

The position of the first lever is changed by the cooperation between the control stem and the first lever, and the position of the second lever is changed by the cooperation between the first lever and the second lever.

Advantageously, the first rod may carry a positioning pin arranged to cooperate with the second rod, the cooperation between the positioning pin and the second rod defining the position of the second rod.

Preferably, a return spring may be provided, which is arranged to cooperate with the second lever and ensure contact between the second lever and the first lever.

Advantageously, the second lever may also carry a connecting wheel set comprising a third connecting wheel kinematically connectable to the first drive wheel and a connecting pinion cooperating with the date corrector mechanism.

Preferably, the second lever may comprise a first shaft at a first end, on which the second wheel for time setting is mounted, and a second shaft at a second end, on which the third lever and the connecting wheel set are mounted, the connecting wheel set being fixed to the second shaft.

Advantageously, said third lever may comprise a support arm on which the date corrector mechanism is mounted so as to pivot, and an arm carrying a stop element.

Preferably, a support element may be provided which is arranged to abut against a stop element of the third lever when the control stem and the first and second levers are in the time setting position to pivot the third lever into its retracted position disengaged from the date display mechanism.

Advantageously, the date corrector mechanism may comprise a fourth correction wheel kinematically connectable to the first drive wheel, and a corrector element actuated by the fourth correction wheel and comprising at least one correction finger capable of cooperating with the date display mechanism.

Preferably, said third lever is frictionally mounted on said second shaft of said second lever so as to be fixed to said second shaft during date correction, so as to adopt an engaged position with the date display mechanism when the control stem is rotated in one direction and a withdrawn position in which it is disengaged from the date display mechanism when the control stem is rotated in the other direction; and so as to be disengaged from the second shaft during time setting, so as to pivot into the withdrawn position in which it is disengaged from the date display mechanism when its stop element cooperates with the support element.

Advantageously, a retaining plate can be provided which has an opening for defining the path of the third rod.

The timepiece movement including the date correction mechanism according to the invention allows for a rapid and unidirectional correction of the date by means of a control stem when the date is corrected at midnight, without any risk of damaging the elements of the day-date mechanism. No special cutting of the toothing structure of the wheel and pinion used is required.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will become more apparent on reading the following description of a particular embodiment of the invention, given purely as a non-limiting example, together with the accompanying drawings:

FIG1 is an isometric view of a portion of a mechanism provided in a movement according to the invention;

Figure 2 is an exploded view of the third lever, the date correction mechanism, and the date display mechanism;

FIG3 is a front view of the mechanism shown in FIG1 in the manual winding position;

FIG4 is a front view of the mechanism shown in FIG1 in the date correction position with the third lever in its engaged position;

FIG5 is a front view of the mechanism shown in FIG1 in the date correction position with the third lever in its retracted position; and

FIG. 6 is a front view of the mechanism shown in FIG. 1 in a time setting position.

DETAILED DESCRIPTION

FIG. 1 shows a portion of a timepiece movement comprising, in particular, a control stem 1 , a winding mechanism, a date display mechanism and a time display mechanism.

Typically, a control stem 1 or winding stem is accessible from the outside of the movement's case, capable of both rotational and translational movement to adopt its different positions. A winding pinion 2 and a sliding pinion 4 are also provided, the positioning of which is ensured by a pull-out 6 and a lever 8.

Typically, as shown in FIG3 , when the control stem occupies its winding position (generally a position in which the control stem is not pulled out) and when sliding pinion 4 collaborates with winding pinion 2 , winding pinion 2 meshes with a winding mechanism (not shown) for manual winding of the movement.

The date display mechanism generally comprises a day-date disc or ring 10 with an inner toothing 11 which can be actuated by the day-date mechanism.

The time display mechanism may include an intermediate wheel assembly meshing with a going train wheel cooperating with the cannon pinion.

All of these elements and their operation are known to those skilled in the art and need no further detailed description.

According to the invention, a first lever 12 is provided, which is mounted so as to pivot on the frame and carries a first drive wheel 14, which is mounted so as to rotate freely about an axis formed by a pin 16. This pin 16 is a positioning pin, the function of which will be explained below. When the control stem is in the correction or time-setting position (pulled position), the first drive wheel 14 allows the sliding pinion 4 of the control stem 1 to mesh with it. Another pin 18 is provided on the frame and forms a stop for the first lever 12.

A second lever 20 is also provided, mounted to pivot on the frame. More specifically, referring to Figures 1 and 4 , the second lever 20 includes a first arm 20a, through which a first axis A, forming the pivot axis A of the second lever 20 on the frame, passes at its free end. The first arm 20a terminates in a first nose 22. The first nose 22 is arranged to cooperate with a return spring 23 provided on the frame. The return spring 23 is arranged to cooperate with the second lever 20 via the first nose 22 and ensure contact between the second lever 20 and the first lever 12.

The second wheel 24 for time setting is mounted so as to rotate freely on pivot axis A and is arranged to permanently cooperate with the time display mechanism, more specifically with one of the elements of the intermediate wheel assembly. The second wheel 24 for time setting can be kinematically connected to the first drive wheel 14.

The second rod 20 further comprises a second arm 20 b having a second nose 26 located laterally to one side of the first rod 12. The second nose 26 is arranged to cooperate with a positioning pin 16 provided on the first rod 12, wherein the cooperation between the positioning pin 16 and the second nose 26 defines the position of the second rod 20.

The second arm 20b carries, at its free end, a second shaft 28, on which a connecting wheel set and a third lever 30 are mounted. The connecting wheel set includes a third connecting wheel 32 that can be kinematically connected to the first drive wheel 14, and a connecting pinion 34 arranged to cooperate with the date correction mechanism. The third connecting wheel 32 and the connecting pinion 34 are fixedly mounted on the second shaft 28. As will be explained below, the third lever 30 is frictionally mounted on the second shaft 28.

Third lever 30 carries a date corrector mechanism that can be kinematically connected to first drive wheel 14 and also to day-date ring 10. More specifically, with reference to FIG2 , this date corrector mechanism comprises a fourth corrector wheel 36 that can be kinematically connected to first drive wheel 14 via connecting pinion 34 and connecting wheel 32, and a corrector element 38 that includes a correction finger 40 that can cooperate with inner toothing 11 of day-date ring 10. Corrector element 38 is frictionally mounted on fourth correction wheel 36 by means of a shaft 42 fixed to corrector element 38. In normal operation, corrector element 38 and fourth correction wheel 36 are fixed, and the assembly is mounted so as to be movable in rotation on third lever 30.

In the example shown, the correction finger cooperates directly with the day-of-the-week disc, but it will be clear that a wheel train or other intermediate mechanism may be provided between this correction element 38 and the time display mechanism.

The third lever 30 includes a support arm 30a, and a shaft 42 for mounting the date corrector mechanism on the third lever 30 and a shaft 28 for mounting the third lever 30 on the second lever 20 are mounted on the support arm 30a so as to pass through the support arm. The third lever 30 is mounted so as to pivot on the second lever 20 and is arranged to move between an engaged position in which the date corrector mechanism cooperates with the day-date ring 10 and a retracted position in which the date corrector mechanism is disengaged from the day-date ring 10.

The third lever 30 also comprises an arm 30b carrying a stop element 30c.

As will be described below, a support element 44 is also provided on the frame and is arranged to abut against a stop element 30 c of the third lever 30 to pivot the third lever 30 to a retracted position separated from the date display mechanism.

The frame is also provided with a retaining plate 46 having an opening and arranged relative to the corrector element 38 in such a way that the shaft 42 of the date corrector mechanism circulates freely in the opening, wherein the edge of the opening thus allows the path of the third lever 30 to be defined.

The movement according to the invention operates as follows: in the manual-winding position, as shown in FIG3 , sliding pinion 4 meshes with winding pinion 2, which in turn meshes with a winding mechanism (not shown) for manually winding the movement. Control stem 1, thus occupying its winding position, is kinematically connected to the movement's winding mechanism and is not kinematically connected to first drive wheel 14 and, consequently, to any other time or date display mechanism. First lever 12 abuts against pin 18. Return spring 23, bearing against nose 22, ensures contact between nose 26 of second lever 20 and pin 16 fixed to first lever 12.

4 , when control stem 1 is pulled outward to its date correction position, sliding pinion 4 performs a translational movement toward first drive wheel 14 and then meshes with it. First lever 12 abuts against pin 18. Return spring 23, bearing against nose 22, ensures contact between nose 26 of second lever 20 and pin 16 fixed to first lever 12. In this date correction position, the control stem is thus kinematically connected to first drive wheel 14, and first and second levers 12, 20 are positioned so that first drive wheel 14 is kinematically connected to the date correction mechanism carried by third lever 30 and not kinematically connected to second wheel 24 for time setting. More precisely, second lever 20 is positioned so that first drive wheel 14 meshes with third connecting wheel 32 carried by second lever 20. As a result, connecting pinion 34, fixed to third connecting wheel 32, is driven in rotation and meshes with fourth correction wheel 36 carried by third lever 30. This causes correction element 38, fixed to said fourth correction wheel 36, to be driven in rotation, causing one of correction fingers 40 to engage toothed ring 11 of day-date ring 10 and actuate it to correct the date. Second lever 20 is positioned so that first drive wheel 14 does not interact with second wheel 24 for time setting. Thus, the rapid date correction function operates independently of the time-setting and winding functions.

In this position, third lever 30 is fixed to shaft 28, which carries the connecting wheel set (third connecting wheel 32 and connecting pinion 34). Thus, rotation of control stem 1 in one direction causes the connecting wheel set and shaft 28 to rotate in one direction, and thus pivots third lever 30 in the same direction. This pivoting movement in this direction, for example, moves support arm 30a of third lever 30, and therefore the date corrector mechanism, toward day-date ring 10, as shown in FIG4 . Third lever 30 then assumes its meshing position with day-date ring 10. The displacement of the date corrector mechanism toward day-date ring 10, and the resulting meshing between correction element 38 and day-date ring 10, is facilitated by the edge of an opening provided in retaining plate 46. Thus, date correction is possible.

When the control stem 1 is rotated in the opposite direction, this causes the connecting wheel set and shaft 28 to rotate in the opposite direction, and thus the third lever 30 to pivot in the same opposite direction. This pivoting movement in the opposite direction causes the support arm 30a of the third lever 30, and therefore the date corrector mechanism, to move away from the day-date ring 10, as shown in FIG5 . The third lever 30 then assumes its retracted position, separated from the day-date ring 10. The movement of the date corrector mechanism away from the day-date ring 10 is limited by the edge of the opening provided in the retaining plate 46. Since the date corrector mechanism is separated from the day-date ring 10, the date can no longer be corrected even if the control stem is actuated. The mechanism according to the present invention thus allows unidirectional correction of the date using the control stem.

With third lever 30 already in the engaged position in which corrector element 38 is engaged with day-of-the-day ring 10, the frictional mounting of said corrector element 38 on fourth correction wheel 36 allows said corrector element 38 to be disengaged from said fourth correction wheel 36 and causes corrector element 38 to pivot under the pressure of day-of-the-day ring 10 during a normal date change.

6 , when control stem 1 is pulled outward again to its time-setting position, sliding pinion 4 performs a new translational movement in the direction of first lever 12. Control stem 1 then cooperates with first lever 12 to pivot it toward second lever 20, thereby meshing first drive wheel 14 with second time-setting wheel 24, with sliding pinion 4 still meshing with first drive wheel 14. Return spring 23, bearing against nose 22, ensures contact between nose 26 of second lever 20 and pin 16 fixed to first lever 12. In this time-setting position, control stem 1 is thus kinematically connected to first drive wheel 14, and first lever 12 and second lever 20 are positioned so that first drive wheel 14 is kinematically connected to second time-setting wheel 24, allowing the time-setting operation to proceed, and is not kinematically connected to the date correction mechanism carried by third lever 30. More precisely, during the tilting of first lever 12, the cooperation between pin 16 and second lever 20 causes the second lever 20 to tilt about axis A, moving the second lever from its date correction position to its time setting position, thereby disengaging third connecting wheel 32 carried by said second lever 20 from first drive wheel 14. The time-setting function is thus independent of the rapid date correction function and the winding function.

As shown in FIG6 , when the second lever 20 is tilted to its time-setting position, the stop element 30 c of the third lever 30 comes to rest on the support element 44, whereby the third lever 30, due to the frictional mounting, disengages from the shaft 28 and pivots to its retracted position separated from the day-date ring 10. The seating of the third lever in its retracted position ensures that the date corrector mechanism does not cooperate with the day-date ring 10 during the time-setting operation.

In the movement according to the invention, the meshing between the first driving wheel and the date display or time-setting mechanism is non-permanent and, therefore, no special cutting of the toothing structure of the different components is required. This meshing is controlled by the positioning of a first lever 12 and a second lever 20 in contact with a pin 16 of the first lever 12, wherein contact between the first lever 12 and the second lever 20 is ensured by a return spring 23.

Furthermore, the mechanism provided is compact and requires little space. In the architecture of a movement including a chronograph mechanism, this advantageously allows sufficient space to be left to arrange a minute counter mechanism at 3 o'clock close to the control stem.

Claims (10)

1. A watch movement comprising a control stem (1), a winding mechanism for winding the movement, a date display mechanism, and a time display mechanism, characterized in that the watch movement comprises a first rod (12) carrying a first drive wheel (14) kinematically connected to the control stem (1), a second rod (20) carrying a second wheel (24) for time setting arranged to cooperate with the time display mechanism and kinematically connected to the first drive wheel (14), and a third rod (30) carrying a date correction mechanism kinematically connected to the first drive wheel (14) and also connected to the date display mechanism, wherein the third rod (30) is mounted to pivot on the second rod (20) and arranged to move between an engaged position and a retracted position, wherein in the engaged position the date correction mechanism cooperates with the date display mechanism, and in the retracted position the date correction mechanism is disengaged from the date display mechanism, and wherein the control stem (1) and the first rod (12) and the second rod (20) are arranged to occupy three positions: - The winding position, wherein the control stem shaft (1) is kinematically connected to the winding mechanism for winding the movement and is not kinematically connected to the first drive wheel (14); - Date correction position, wherein the control handle shaft (1) is kinematically connected to the first drive wheel (14), and the first lever (12) and the second lever (20) are positioned such that the first drive wheel (14) is kinematically connected to the date correction mechanism and not kinematically connected to the second wheel (24) for time setting; and - Time setting position, wherein the control handle shaft (1) is kinematically connected to the first drive wheel (14), and the first lever (12) and the second lever (20) are positioned such that the first drive wheel (14) is kinematically connected to the second wheel (24) for time setting and is not kinematically connected to the date correction mechanism. The position of the first lever (12) is changed by the cooperation between the control handle (1) and the first lever (12), and the position of the second lever (20) is changed by the cooperation between the first lever (12) and the second lever (20). 2. The watch movement according to claim 1, characterized in that the first rod (12) carries a positioning pin (16) arranged to cooperate with the second rod (20), the cooperation between the positioning pin (16) and the second rod (20) defining the position of the second rod (20). 3. The watch movement according to claim 1, characterized in that a return spring (23) is provided, the return spring being arranged to cooperate with the second rod (20) and ensure contact between the second rod (20) and the first rod (12). 4. The watch movement according to claim 1, wherein the second rod (20) further carries a connecting wheel assembly, the connecting wheel assembly including a third connecting wheel (32) that can be kinematically connected to the first drive wheel (14) and a connecting pinion (34) that cooperates with the date correction mechanism. 5. The watch movement according to claim 4, characterized in that the second lever (20) includes a first shaft (A) at a first end and a second shaft (28) at a second end, the second wheel (24) for time setting is mounted on the first shaft (A), the third lever (30) and the connecting wheel assembly are mounted on the second shaft (28), and the connecting wheel assembly is fixed to the second shaft (28). 6. The watch movement according to claim 5, wherein the third lever (30) comprises a support arm (30a) and an arm portion (30b) for carrying a stop element (30c), the date correction mechanism being mounted to pivot on the support arm. 7. The watch movement according to claim 6, characterized in that a support element (44) is provided, wherein when the control stem (1) and the first rod (12) and the second rod (20) are in the time setting position, the support element is arranged to abut against the stop element (30c) of the third rod (30) so that the third rod (30) pivots to a retracted position separated from the date display mechanism. 8. The watch movement according to claim 1, characterized in that the date correction mechanism includes a fourth correction wheel (36) kinematically connected to the first drive wheel (14), and a correction element (38) actuated by the fourth correction wheel (36) and including at least one correction pawl (40) cooperating with the date display mechanism. 9. The watch movement according to claim 7, characterized in that the third lever (30) is frictionally mounted on the second shaft (28) of the second lever (20) so as to be fixed to the second shaft (28) during date correction, thereby occupying an engaged position with the date display mechanism when the control stem shaft (1) rotates in one direction and occupying a retracted position separated from the date display mechanism when the control stem shaft (1) rotates in another direction; and the third lever (30) is frictionally mounted on the second shaft (28) of the second lever (20) so as to disengage from the second shaft (28) during time setting, thereby pivoting the third lever to the retracted position separated from the date display mechanism when the stop element of the third lever cooperates with the support element (44). 10. The watch movement according to claim 1, characterized in that it is provided with a retaining plate (46) having an opening for defining the path of the third rod (30).