HK1235109A1 - Timepiece movement comprising a date correction mechanism - Google Patents

Description

Timepiece movement including a date correction mechanism

Technical Field

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

Background

Many mechanical watches classically comprise a control stem arranged in the 3 o' clock position and able to occupy two positions, namely a manual winding position and a time-setting position. These watches may also include a date display mechanism. The rapid correction of the date is carried out by means of a button provided on the watchcase at a different position from the control stem, for example at the 10 o' clock position. However, this configuration requires an opening in the case for the push-button to pass through, with the drawback of weakening the seal of the watch and limiting the choice of decorative design of the watch.

One solution to these problems is proposed in patent EP 2707778, which consists in correcting the date by means of a control stem arranged to occupy a third position. However, in this mechanism, the correcting element for the date is fixed and therefore permanently engaged with the day calendar ring (day date ring), and the correction of the date is made in both directions. If the user makes a date correction at midnight, there is a risk of destroying the date-driving arm. Furthermore, the wheels of the second wheel set carried by the second lever permanently mesh with the pinion carried by the first lever, the connection between these components being ensured by their respective toothed rings. This configuration requires a special cutting of the ring gear arrangements so that they have concentric profiles to prevent any jamming.

Disclosure of Invention

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

More precisely, it is an object of the present invention to provide a timepiece movement that allows a rapid correction of the date by means of the control stem, and that does not require openings in the case associated with the push-button, which were previously necessary for performing this function.

It is also an object of the invention to provide a timepiece movement that allows 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 drive wheel which can be kinematically connected to the control stem, a second lever carrying a second wheel for time setting arranged to cooperate with the time display mechanism and can be kinematically connected to the first drive wheel, and a third lever carrying a date correction mechanism which can be kinematically connected to the first drive wheel and to the date display mechanism, wherein said third lever is mounted so as to pivot on the second lever and is arranged so as to move between an engagement position, in which said date correction mechanism cooperates with the date display mechanism, and a withdrawn position, in which said date correction mechanism is disconnected from the date display mechanism, and said control stem and said first and second levers are arranged so as 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 drive wheel;

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

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

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

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

Preferably, a return spring may be provided, 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 group comprising a third connecting wheel able to be kinematically connected to the first driving wheel and a connecting pinion cooperating with the date correction mechanism.

Preferably, the second lever may comprise a first shaft at a first end on which a second wheel for time setting is mounted and a second shaft at a second end on which the third lever and a 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 correction mechanism is mounted to pivot, and an arm carrying the stop element.

Preferably, a support element may be provided, 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, so as to pivot the third lever to its retracted position disconnected from the date display mechanism.

Advantageously, the date correction mechanism may comprise a fourth correction wheel which can be kinematically connected to the first drive wheel, and a correction element actuated by the fourth correction wheel and comprising at least one correction finger which can cooperate 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 this second shaft during date correction, so as to occupy an engaged position with the date display mechanism when the control stem is rotated in one direction and a retracted position in which it is disengaged from the date display mechanism when the control stem is rotated in the other direction; and to disengage from the second shaft during the time setting to pivot to a withdrawn position disconnected from the date display mechanism when its stop element cooperates with the support element.

Advantageously, a retaining plate may be provided, the retaining plate having an opening for defining the path of the third bar.

The timepiece movement according to the invention, including the date correction mechanism, allows a quick and unidirectional correction of the date by means of the control stem when correcting the date at midnight, without any risk of damaging the elements of the day calendar mechanism (day calendar). No special cutting of the ring gear structure of the wheels and pinions used is required.

Drawings

Other characteristics and advantages of the invention will become clearer after reading the following description of a particular embodiment of the invention, given purely by way of non-limiting example, and with reference to the attached drawings:

figure 1 is an isometric view of a portion of a mechanism provided in a movement according to the invention;

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

FIG. 3 is a front view of the mechanism shown in FIG. 1 in a manual winding position;

FIG. 4 is a front elevational view of the mechanism illustrated in FIG. 1 in the date correction position with the third lever in its engaged position;

FIG. 5 is a front elevational view of the mechanism illustrated in FIG. 1 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-set position.

Detailed Description

Fig. 1 shows a part of a timepiece movement including, in particular, a control stem 1, a winding mechanism, a date display mechanism and a time display mechanism.

Usually, the control stem 1 or winding stem is operable from the outside of the case of the movement, both in a rotary movement and in a translational movement to occupy its different positions. Winding pinion 2 and sliding pinion 4 are also provided, the positioning of sliding pinion 4 being ensured by pull-out piece 6 and lever 8.

Normally, as shown in fig. 3, when the control stem occupies its winding position (normally the position in which the control stem is not pulled out) and when sliding pinion 4 cooperates with winding pinion 2, winding pinion 2 meshes with a winding mechanism (not shown) to perform manual winding of the movement.

The date display mechanism typically comprises a day calendar disc or ring 10 with an internal toothed ring 11 that can be actuated by the day calendar mechanism.

The time display mechanism may comprise an intermediate wheel assembly in engagement with a motion gear wheel which cooperates with the minute gear shaft.

All these elements and their operation are known to the person skilled in the art and need not be described in more detail.

According to the invention, a first lever 12 is provided, which is mounted to pivot on the frame and carries a first drive wheel 14, which first drive wheel 14 is mounted to rotate freely about an axis formed by a pin 16. The pin 16 is a locating pin, the function of which will be explained below. When the control stem is in the correction or time-setting position (pulled-out position), first drive wheel 14 allows sliding pinion 4 of control stem 1 to mesh therewith. A further 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. Referring more particularly to fig. 1 and 4, the second lever 20 comprises a first arm 20a through which a first axis a forming a pivot axis a of the second lever 20 on the frame passes at a free end of the first arm 20 a. 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. Said return spring 23 is arranged to cooperate with the second lever 20 by means of the first nose 22 and to ensure contact between said second lever 20 and said first lever 12.

The second wheel 24 for time setting is mounted to rotate freely on the pivot axis a and is arranged to cooperate permanently with the time display mechanism, more particularly 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 lever 20 further comprises a second arm 20b having a second nose 26 located laterally to one side of the first lever 12. This second nose 26 is arranged to cooperate with a positioning pin 16 provided on the first rod 12, wherein the cooperation between said positioning pin 16 and said second nose 26 defines the position of the second rod 20.

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

The third lever 30 carries a date correction mechanism that can be kinematically connected to the first drive wheel 14 and also to the day calendar ring 10. Referring more particularly to fig. 2, the date correcting mechanism includes a fourth correcting wheel 36 and a correcting element 38, the fourth correcting wheel 36 being kinematically connectable to the first drive wheel 14 via the connecting pinion 34 and the connecting wheel 32, the correcting element 38 including a correcting finger 40 able to cooperate with the internal toothing 11 of the day calendar ring 10. The correction element 38 is frictionally mounted on the fourth correction wheel 36 by means of a shaft 42 fixed to the correction element 38. In normal operation, the correction element 38 and the fourth correction wheel 36 are fixed and the assembly is mounted for rotational movement on the third rod 30.

In the example shown, the correcting finger cooperates directly with the day disc, but it will be clear that a train of wheels or other intermediate means can be provided between the correcting element 38 and the time display mechanism.

The third lever 30 includes a support arm 30a, and a shaft 42 for mounting the date correcting 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 this second lever 20 and is arranged to move between an engagement position, in which the date correction mechanism cooperates with the day calendar ring 10, and a retracted position, in which the date correction mechanism is separated from the day calendar ring 10.

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

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

A holding plate 46 is also provided on the frame, which holding plate has an opening and is arranged with respect to the correction element 38 in such a way that the shaft 42 of the date correction mechanism freely circulates in the opening, wherein the edge of said opening thus allows the path of the third rod 30 to be defined.

The movement according to the invention operates as follows: in the manual winding position, as shown in fig. 3, sliding pinion 4 meshes with winding pinion 2, and winding pinion 2 meshes with a winding mechanism (not shown) to perform manual winding of the movement. The control stem 1, which occupies its winding position, is therefore kinematically connected to the winding mechanism of the movement and is not kinematically connected to the first drive wheel 14 and therefore also to other time or date display mechanisms. The first lever 12 abuts the pin 18. The return spring 23 rests against the nose 22, ensuring the contact of the nose 26 of the second lever 20 with the pin 16 fixed to the first lever 12.

Referring to fig. 4, when control stem 1 is pulled outwards to its date correction position, sliding pinion 4 performs a translational movement towards first drive wheel 14 and then meshes with first drive wheel 14. The first lever 12 abuts the pin 18. The return spring 23 rests against the nose 22, ensuring contact between the nose 26 of the second lever 20 and the pin 16 fixed to the first lever 12. In the date correction position, the control stem is therefore kinematically connected to the first drive wheel 14, and the first lever 12 and the second lever 20 are positioned so that the first drive wheel 14 is kinematically connected to the date correction mechanism carried by the third lever 30 and not kinematically connected to the second wheel 24 for time setting. More precisely, the second lever 20 is positioned so that the first driving wheel 14 meshes with a third connecting wheel 32 carried by said second lever 20. Thus, the connecting pinion 34 fixed to the third connecting wheel 32 is driven in rotation and meshes with a fourth correction wheel 36 carried by the third lever 30, so that a correction element 38 fixed to said fourth correction wheel 36 is driven in rotation, so that one of the correction fingers 40 cooperates with the toothing 11 of the day calendar ring 10 and actuates it to correct the date. The second lever 20 is positioned such that the first drive wheel 14 does not cooperate with the second wheel 24 for time setting. Therefore, the quick date correcting function is independent of the time setting function and the winding function.

In this position, the third lever 30 is fixed to the shaft 28 carrying the set of connecting wheels (third connecting wheel 32 and connecting pinion 34). Thus, rotation of the control stem 1 in one direction causes rotation of the connecting wheel set and the shaft 28 in one direction, and therefore the third lever 30 pivots in the same direction, wherein pivotal movement in this direction, for example, moves the support arm 30a of the third lever 30 and therefore the date correcting mechanism toward the day calendar ring 10, as shown in fig. 4. Thereafter, the third lever 30 occupies its engagement position with the day calendar ring 10. The displacement of the date correcting mechanism toward the day calendar ring 10 and therefore the engagement between the correcting element 38 and the day calendar ring 10 is carried out with the aid of the edge of the opening provided on the holding plate 46. Thus, date correction can be performed.

When the control stem 1 is rotated in the opposite direction, this causes the connecting wheel set and the shaft 28 to rotate in the opposite direction, and therefore, the third lever 30 pivots in the same opposite direction, and this pivotal movement in the opposite direction causes the support arm 30a of the third lever 30 and therefore the date correcting mechanism to move in a direction away from the day calendar ring 10, as shown in fig. 5. Thereafter, the third lever 30 occupies its retracted position separated from the day calendar ring 10. The movement of the date correcting mechanism away from the day calendar ring 10 is restricted by the edge of the opening provided on the holding plate 46. Since the date correction mechanism is separated from the day calendar ring 10, date correction cannot be performed any more even if the control stem is actuated. The mechanism according to the invention thus allows a unidirectional correction of the date by means of the control stem.

In the case where the third lever 30 has stayed in the engaged position in which the correction element 38 is engaged with the day calendar ring 10, the frictional mounting of the correction element 38 on the fourth correction wheel 36 allows the correction element 38 to disengage from the fourth correction wheel 36 and causes the correction element 38 to pivot under the pressure of the day calendar ring 10 during normal date changes.

When control stem 1 is pulled outwards again to its time-set position, sliding pinion 4 performs a new translational movement in the direction of first rod 12, see fig. 6. Thereafter, control stem 1 cooperates with first lever 12 to pivot first lever 12 in the direction of second lever 20, so that first drive wheel 14 meshes with second wheel 24 for time setting, with sliding pinion 4 still meshing with first drive wheel 14. The return spring 23, resting on the nose 22, ensures the contact of the nose 26 of the second lever 20 with the pin 16 fixed to the first lever 12. In this time-setting position, control stem 1 is therefore kinematically connected to first driving wheel 14, and first lever 12 and second lever 20 are positioned so that first driving wheel 14 is kinematically connected to second wheel 24 for time-setting to allow the time-setting operation, and is not kinematically connected with the date correction mechanism carried by third lever 30. More precisely, during the tilting of the first lever 12, the cooperation between the pin 16 and the second lever 20 causes the second lever 20 to tilt about the axis a, moving from its date correction position to its time-set position, so that the third connecting wheel 32 carried by said second lever 20 is disengaged from the first driving wheel 14. Therefore, the time setting function is independent of the quick date correcting function and the winding function.

As shown in fig. 6, when the second lever 20 is tilted to its time-set position, the stopper member 30c of the third lever 30 abuts on the support member 44, thereby frictionally mounting the third lever 30 out of engagement with the shaft 28 and pivoting to its retracted position separated from the day calendar ring 10. The positioning of the third lever in its retracted position ensures that the date correcting mechanism does not cooperate with the day calendar ring 10 during the time setting operation.

In the movement according to the present invention, the engagement between the first drive wheel and the date display mechanism or the time setting mechanism is non-permanent, and therefore, the ring gear structure of the different parts does not need to be specially cut. The engagement between the first driving wheel and the date display mechanism or the time-setting mechanism is controlled by the positioning of the first lever 12 and the second lever 20 in contact with the pin 16 of said first lever 12, wherein the return spring 23 ensures the contact between said first lever 12 and the second lever 20.

In addition, the provided mechanism is compact in structure and small in space requirement. In the frame of the movement comprising the chronograph mechanism, it is advantageously allowed to leave sufficient space to arrange the minute counting mechanism close to the control stem in the 3 o' clock position.

Claims (10)

1. Timepiece 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 it comprises a first lever (12) carrying a first drive wheel (14) which can be kinematically connected to the control stem (1), a second lever (20) carrying a second wheel (24) for time setting arranged to cooperate with the time display mechanism and which can be kinematically connected to the first drive wheel (14), and a third lever (30) carrying a date correction mechanism which can be kinematically connected to the first drive wheel (14) and which is also connected to the date display mechanism, wherein said third lever (30) is mounted so as to pivot on the second lever (20) and is arranged to move between an engagement position, in which it cooperates with the date display mechanism, in the retracted position, the date correction mechanism is separated from the date display mechanism, and wherein the control stem (1) and the first (12) and second (20) levers are arranged to occupy three positions:

-a winding position, in which the control stem (1) is kinematically connected to a winding mechanism for winding the movement and is not kinematically connected to the first drive wheel (14);

-a date correction position, wherein the control stem (1) is kinematically connected to a first driving wheel (14) and the first lever (12) and the second lever (20) are positioned so that the first driving wheel (14) is kinematically connected to a date correction mechanism and not kinematically connected to a second wheel (24) for time setting; and

-a time-setting position, in which the control stem (1) is kinematically connected to the first driving wheel (14) and the first lever (12) and the second lever (20) are positioned so that the first driving wheel (14) is kinematically connected to the second wheel (24) for time setting and is not kinematically connected to a date correction mechanism,

wherein the position of the first lever (12) is changed by cooperation between the control stem (1) and the first lever (12), and the position of the second lever (20) is changed by cooperation between the first lever (12) and the second lever (20).

2. Timepiece movement according to claim 1, wherein the first lever (12) carries a detent pin (16) arranged to cooperate with a second lever (20), the cooperation between the detent pin (16) and the second lever (20) defining the position of the second lever (20).

3. Timepiece movement according to claim 1, wherein a return spring (23) is provided, which is arranged to cooperate with the second lever (20) and to ensure contact between the second lever (20) and the first lever (12).

4. Timepiece movement according to claim 1, wherein the second lever (20) also carries a connecting wheel set comprising a third connecting wheel (32) kinematically connectable to the first driving wheel (14) and a connecting pinion (34) cooperating with the date correction mechanism.

5. Timepiece movement according to claim 4, wherein the second lever (20) comprises a first shaft (A) at a first end on which the second wheel (24) for time setting is mounted and a second shaft (28) at a second end, the third lever (30) and the set of connecting wheels being mounted on the second shaft (28), the set of connecting wheels being fixed to the second shaft (28).

6. Timepiece movement according to claim 1, wherein the third lever (30) comprises a support arm (30a) on which the date correction mechanism is mounted to pivot, and an arm (30b) carrying a stop element (30 c).

7. Timepiece movement according to claim 6, wherein a support element (44) is provided which is arranged to abut against a stop element (30c) of the third lever (30) when the control stem (1) and the first and second levers (12, 20) are in the time-setting position, so as to pivot the third lever (30) to a retracted position separated from the date display mechanism.

8. Timepiece movement according to claim 1, wherein the date correction mechanism comprises a fourth correction wheel (36) which can be kinematically connected to the first drive wheel (14), and a correction element (38) actuated by the fourth correction wheel (36) and comprising at least one correction finger (40) which can cooperate with the date display mechanism.

9. Timepiece movement according to claims 5, 7 and 8, characterised 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 said second shaft (28) during date correction, so as to occupy an engaged position with the date display mechanism when the control stem (1) is rotated in one direction and a withdrawn position disengaged from the date display mechanism when the control stem (1) is rotated in the other direction; and, said 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 the time setting, so as to be pivoted to a retracted position disengaged from the date display mechanism when its stop element cooperates with the support element (44).

10. Timepiece movement according to claim 1, wherein a retaining plate (46) is provided, having an opening for defining the path of the third lever (30).