CONTROL DEVICE FOR A TIMEPIECE

A control device (1) for a  timepiece has: - a body (4) intended to be mounted to be able to rotate about an axis of rotation (X) in a case middle (2) of a timepiece in order to drive a mechanism of the timepiece, and: - a crown head (5) movable in translation with respect to the body, parallel to the axis of rotation, between a first position and a second position. The body has a first coupling means (46) and the crown head has a second coupling means (53), arranged so that when the crown head is in its first position, the body and the crown head are uncoupled, and when the crown head is in its second position, the body and the crown head are coupled, the control device further comprising a locking element (6), a first formation (47A) and a second formation (47B), the locking element being able to cooperate with the first formation to stabilize the crown head in its first position, and with the second formation to stabilize the crown head in its second position, the locking element being integral with or fixed to the crown head and the first and second formations being integral with or fixed to the body, or the locking element being integral with or fixed to the body and the first and second formations being integral with or fixed to the crown head.

This application claims priority of Swiss patent application No. CH070455/2021 filed Oct. 27, 2021, the content of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD OF THE INVENTION

The invention relates to a control device for a timepiece, the control device comprising a crown head movable in translation. The invention also relates to a timepiece comprising such a control device.

BACKGROUND ART

Certain timepieces are equipped with a control device that serves to actuate a mechanism of the timepiece, such as a mechanism for rewinding a barrel or a mechanism for adjusting the time. The control device comprises a crown head movable between two positions: a first position, referred to as uncoupled position, is a position in which a rotation of the crown head does not drive any particular mechanism. A second position, referred to as coupled position, is a position in which the crown head is coupled to a crown body. A rotation of the crown head drives the rotation of the crown body which itself drives said mechanism.

The known control devices have all or some of the following drawbacks:they can wear rapidly due to the intentional or unintentional actuation of the crown head;they are large and greatly restrict the esthetic aspect of the timepiece;the crown head is difficult to manipulate;the control device is ungainly when the crown head occupies one or other of the coupled or uncoupled positions.

SUMMARY OF THE INVENTION

The aim of the invention is to provide a control device and a timepiece comprising such a control device which remedy the above drawbacks and improve the control devices and timepieces known from the prior art.

More precisely, a primary subject of the invention is a control device for a timepiece, said control device being particularly compact, durable and easy to manipulate.

According to a first aspect of the invention, the control device is defined by point 1 below.

1. A control device (1) for a timepiece, comprising:a body (4) intended to be mounted so as to be able to rotate about an axis of rotation (X) in a case middle (2) of a timepiece in order to drive a mechanism of the timepiece, anda crown head (5) movable in translation with respect to said body, parallel to the axis of rotation, between a first position and a second position,the body comprising a first coupling means (46) and the crown head comprising a second coupling means (53), said first and second coupling means being arranged such that when the crown head is in its first position, the body and the crown head are uncoupled, and such that when the crown head is in its second position, the body and the crown head are coupled,the control device further comprising a locking element (6), a first formation (47A) and a second formation (47B), the locking element being able to cooperate with the first formation to stabilize the crown head in its first position, the locking element being able to cooperate with the second formation to stabilize the crown head in its second position,the locking element being integral with or fixed to the crown head and the first and second formations being integral with or fixed to the body, or the locking element being integral with or fixed to the body and the first and second formations being integral with or fixed to the crown head.

According to a second aspect of the invention, the control device is defined by point 5 below.

5. A control device for a timepiece, comprising:a body intended to be mounted so as to be able to rotate about an axis of rotation in a case middle of a timepiece in order to drive a mechanism of the timepiece, anda crown head movable in translation with respect to said body, parallel to the axis of rotation, between a first position and a second position,the body comprising a first coupling means and the crown head comprising a second coupling means, said first and second coupling means being arranged such that when the crown head is in its first position, the body and the crown head are uncoupled, and such that when the crown head is in its second position, the body and the crown head are coupled,the body comprising a first indexing means and the crown head comprising a second indexing means, said first and second indexing means being arranged in such a way as to stabilize the crown head in its first position and in its second position,the crown head comprising a tubular part and the body comprising an annular opening able to receive within it the tubular part, the second coupling means being arranged on a first wall of the tubular part, notably an external wall of the tubular part or respectively an internal wall of the tubular part, and the second indexing means being arranged on a second wall of the tubular part, notably an internal wall of the tubular part or respectively an external wall of the tubular part, the second wall being opposite to the first wall.

Embodiments of the control device are defined by points 2 to 4 and 6 to 9 below.

2. The control device as defined in the preceding point, wherein the locking element has a shape that exhibits symmetry of revolution centered about said axis of rotation, notably a toric shape, and wherein the first and second formations are grooves of a shape that is substantially complementary to the shape of a part of the locking element.

3. The control device as defined in either of the preceding points, wherein the crown head comprises a tubular part, and wherein the body comprises an annular opening able to receive within it the tubular part, the second coupling means being arranged on a first wall of the tubular part, and the locking element or the first and second formations being arranged on a second wall of the tubular part, the second wall being opposite to the first wall.

4. The control device as defined in the preceding point, whereinthe locking element is integral with or fixed to the crown head, and wherein the first and second formations are integral with or fixed to the body, and/or whereinthe first wall is an external wall of the tubular part, and wherein the second wall is an internal wall of the tubular part.

6. The control device as defined in one of the preceding points, wherein the first coupling means comprises a first set of splines, and wherein the second coupling means comprises a second set of splines.

7. The control device as defined in one of the preceding points, wherein it comprises a retaining means, notably a retaining screw, which is integral with the body and which passes through an opening in the crown head, the retaining means cooperating with a retaining surface of the crown head to limit the movement in translation of the crown head parallel to the axis of rotation.

8. The control device as defined in one of the preceding points, wherein the body comprises a cylindrical wall that forms a bearing able to cooperate with a circular opening in the case middle to guide the body in rotation about said axis of rotation.

9. The control device as defined in one of the preceding points, wherein the crown head further comprises a rotation prevention means, notably a toothed wheel, configured to cooperate with an element of the case middle, such as a lug, to prevent the crown head from rotating when the crown head is in its first position.

According to the invention, the timepiece is defined by point 10 below.

10. A timepiece comprising a case middle provided with an opening (21), and a control device as defined in one of the preceding points, the control device being arranged in the opening.

Embodiments of the timepiece are defined by points 11 and 12 below.

11. A timepiece comprising a case middle provided with an opening, and a control device as defined in point 9, the control device being arranged in the opening, the rotation prevention means being a toothed wheel, the case middle comprising at least one lug able to cooperate with the toothed wheel to prevent the crown head from rotating when the crown head is in its first position.

12. The timepiece as defined in either of points 10 and 11, wherein it comprises a first mechanism, notably a mechanism for rewinding a barrel, and a second mechanism, notably a mechanism for adjusting the time, the body of the control device being connected to the first mechanism and to the second mechanism such that the first mechanism is activated when the crown head is rotated in a first direction of rotation, and such that the second mechanism is activated when the crown head is rotated in a second direction of rotation, opposite to the first direction of rotation.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

FIGS.1to5illustrate a control device1according to one embodiment of the invention. The control device is integrated into a case middle2of a timepiece. The timepiece may notably be a wristwatch or a pocket watch. The case middle2is a part of a case of the timepiece. The case middle2comprises a lateral flank provided with an opening21of circular shape in which the control device1is arranged. The control device1is connected to at least one first mechanism, or movement, an element3of which is partially visible inFIGS.1and2. The first mechanism is arranged inside the case. It may be, for example, a mechanism for rewinding a barrel of the timepiece or a mechanism for adjusting the time.

The control device notably comprises a body4, which may also be called crown body, a crown head5and a locking element6.

The body4is mounted so as to be able to rotate in the case middle2about an axis of rotation X. To this end, the body4comprises a cylindrical external wall41that forms a sliding bearing cooperating with a cylindrical wall delimiting the opening21of the case middle. The cooperation of the cylindrical external wall41with the opening21ensures that the body4is guided in rotation with respect to the case middle2. A seal7, for example of toric shape, is advantageously provided at the interface between the cylindrical external wall41and the opening21to prevent the intrusion of particles and/or liquid inside the timepiece. The seal7is arranged in a groove42provided in the cylindrical external wall41. Said seal is dimensioned in such a way as to come into contact with the cylindrical wall of the case middle2that delimits the opening21. In a variant of the presented embodiment, the groove could also be provided in the cylindrical wall delimiting the opening21, the seal supported in this groove would then cooperate with a cylindrical wall of the body4.

Furthermore, the body4is held axially (that is to say parallel to the axis of rotation X) on the case middle2. In particular, the body4comprises a shoulder43held between, on the one part, a surface22of the case middle2that borders the opening21, and, on the other part, a holding plate8fixed to the case middle2. Advantageously, a clearance is provided between the shoulder43, the surface22and the holding plate8so as to allow the body4to rotate without friction. Thus, the body4is not movable in translation with respect to the case middle2. It has a single degree of freedom to rotate with respect to the case middle2.

The body4is fixed to the element3so as to drive said first mechanism. To this end, the body4comprises an opening44of square cross section (readily visible inFIG.5) centered about the axis of rotation X. The opening44accommodates a pin31which is integral with the element3and which has a shape complementary to the opening44. In a variant, the connection between the element3and the body4could be obtained by any other means, notably by screw fastening. It is noted that “integral with” is understood to mean a mechanical connection without degrees of freedom. Two elements that are integral with one another are therefore two elements that are fixed to one another.

The holding plate8comprises an opening81through which the pin31passes. It comprises a surface82that is coplanar with a surface of a base45of the body4. The holding plate8further comprises a spot face83in which the shoulder43sits. Thus, the holding plate does not increase the overall size of the control device.

The crown head5is movable in translation with respect to the body4, parallel to the axis of rotation X, between a first position, referred to as uncoupled position (illustrated inFIG.1), and a second position, referred to as coupled position (illustrated inFIG.2).

The crown head primarily comprises a disk51intended to be manipulated with the fingers of a user, and a tubular part52able to cooperate with the body4when the crown head is in its second position. The crown head5is configured to be pulled from its first position to its second position and pushed from its second position to its first position. In other words, the first position of the crown head corresponds to a position in which it is pushed, or in other words retracted, against the case middle2. The second position of the crown head corresponds to a position in which it is deployed, or in other words pulled. It should be observed that the passage from the first position to the second position is not obtained by screwing or unscrewing the crown head.

As is readily visible inFIGS.1,2and4, the body4comprises an annular opening49able to receive within it the tubular part52of the crown head. In other words, the annular opening49can accommodate the tubular part52. The annular opening49is centered about the axis of rotation X. The annular opening49is delimited radially by a first wall410, of cylindrical overall shape, forming an external wall of the annular opening and by a second wall411forming an internal wall of the annular opening. The annular opening49is a blind opening, that is to say not a through-opening. The first wall is connected to the second wall at the base45of the body4. The depth of the annular opening49along the axis of rotation X is substantially equal to the height of the tubular part along this same axis.

The body4comprises a first coupling means46, and the crown head5comprises a second coupling means53. In this case, the first coupling means46is formed by a first set of rectilinear splines. These splines, also called serrations, are arranged parallel to the axis of rotation X and distributed along the first wall410. Even more precisely, the first set of splines extends approximately over only a part (notably only half) of the height of the first wall410. That part of the wall410along which the first set of splines extends is positioned more in the direction of the disk51. The wall410thus comprises a zone414that is free of any splines and that is positioned more in the direction of the base45.

The second coupling means53is also formed by a second set of rectilinear splines which are arranged parallel to the axis of rotation X and are distributed along an external wall56of the tubular part. This external wall56also has a cylindrical shape centered about the axis of rotation X. The first set of rectilinear splines is notably readily visible inFIG.4, and the second set of rectilinear splines is notably readily visible inFIG.5.

As is visible inFIG.1, when the crown head is in its first position, the first coupling means46occupy a position that is offset along the axis of rotation X with respect to the second coupling means53. The first set of splines is not in contact with the second set of splines, and so the body4and the crown head5are uncoupled.

As is visible inFIG.2, when the crown head is in its second position, the first coupling means46is positioned opposite the second coupling means53. The first set of splines interlocks with the second set of spines. The body4and the crown head5are coupled, that is to say connected in rotation. When the crown head5is in its second position, a rotation of the crown head about the axis of rotation X therefore drives the body4which itself drives the element3of the first mechanism. The control device can thus be described as a control device with an uncouplable crown.

The first coupling means46may be integrated into a ring412that is itself fixed to the body4. The ring412may notably be secured to the body4by press fitting. Thus, the body4may be formed by the assembly of two components, this facilitating its manufacturing method. In a variant, the body4could be a one-piece component machined from one and the same block of material.

The locking element6is an element for keeping the crown head in position, or in other words an indexing means. The locking element6is configured to selectively cooperate with a first formation47A and with a second formation47B. More particularly, the locking element6is able to cooperate with the first formation47A to stabilize the crown head in its first position. Likewise, the locking element6is able to cooperate with the second formation47B to stabilize the crown head in its second position. The set of two formations47A,47B therefore more generally constitutes a first indexing means, and the locking element6more generally constitutes a second indexing means able to cooperate with the first indexing means. The first position and the second position of the crown head are mechanically stable positions. When the crown head is moved in the vicinity of its first position or of its second position, the cooperation of the two indexing means makes it possible to position the crown head exactly in its first position or in its second position, respectively.

According to the embodiment illustrated, the locking element6is integral with the crown head5, and the first and second formations47A,47B are integral with the body. In particular, the locking element6is held in a groove54of the tubular part52. The groove54is formed in an internal wall55, of cylindrical shape, of the tubular part52. The dimensions of this groove54are such that a small clearance can exist between the edges of the groove and the locking element, notably so as to allow a deformation of the locking element6when the control device is being used. Thus, a “locking element integral with the crown head” is understood to mean there is a mechanical connection between these two elements that ensures a sufficient hold of the locking element on the crown head to realize an indexing function. The first and second formations are formed in the second wall411of the annular opening49, facing the internal wall55. The first and second formations are positioned next to one another along the longitudinal axis X. The distance separating the first formation from the second formation along the axis of rotation X corresponds to the amplitude of movement of the crown head between its first position and its second position.

According to the embodiment illustrated, the locking element6has a shape that exhibits symmetry of revolution centered about the axis of rotation X, notably a toric shape. It may be, for example, an elastomeric ring or a snap ring. The first and second formations are grooves of a shape that is substantially complementary to the shape of a part of the locking element. Notably, the grooves have a cross section in the form of a circular arc. To pass from the first position to the second position, the locking element6compresses in the groove54and relaxes when it is seated in one or other of the first or second formations. The selection of the dimensions of the groove54, of the locking element and of the first and second formations makes it possible to adjust the retaining force produced on the crown head for holding the latter in its first position and in its second position.

According to one variant (not shown), the locking element6could be integral with the body4, and the first and second formations47A,47B could be integral with the crown head. Notably, the locking element could be held in a groove formed in the second wall411, and the first and second formations could be produced in the internal wall55of the tubular part.

According to another embodiment variant (not shown), the first and second coupling means46,53could be arranged respectively on the second wall411of the annular opening49and on the internal wall55of the tubular part52, whereas the locking element6would be arranged on the external wall56of the tubular part52and the first and second formations47A,47B would be arranged on the first wall410of the annular opening49.

According to yet another embodiment variant (not shown), the first and second coupling means46,53could be arranged respectively on the second wall411of the annular opening49and on the internal wall55of the tubular part52, whereas the locking element6would be arranged on the first wall410of the annular opening49and the first and second formations47A,47B would be arranged on the external wall56of the tubular part52.

Irrespective of the configuration selected from among the variants described above, a particularly compact control device is obtained. Specifically, by virtue of the annular shape of the opening49, the body4comprises three concentric walls41,410and411that each ensure a function of the control device. The first wall410accommodates the first coupling means and the free zone414that is devoid of coupling means, the second wall411accommodates an indexing means, and the external wall41forms a guide for guiding the body4in rotation. The size of the body4along the axis of rotation X is therefore dictated solely by the minimum height of each of these three walls41,410and411. Likewise, the annular opening49coincides with the tubular part52of the crown head, said tubular part comprising two concentric walls55,56that each ensure a function of the control device. The internal wall55accommodates an indexing means, and the external wall56accommodates the second coupling means.

The crown head further comprises a rotation prevention means57configured to prevent the crown head from rotating when the crown head is in its first position. In particular, the rotation prevention means57is formed by a toothed wheel integral with the disk51. The toothed wheel is fixed, for example by press fitting, to a lower face of the disk, that is to say that face of the disk51which is oriented toward the case middle. Thus, the toothed wheel remains invisible and protected from impacts. The toothed wheel is integrated into an annular groove provided in the disk51. The toothed wheel comprises a plurality of teeth extending radially, that is to say perpendicularly with respect to the axis of rotation X. As is readily visible inFIG.3(in which the crown head has been rendered transparent), the toothed wheel cooperates with two lugs23, formed in the case middle2, when the crown head is in its first position in order to prevent said crown head from rotating. The lugs23are each positioned between two adjacent teeth of the toothed wheel. In a variant, the number of lugs could be different: for example one lug, three lugs or more, or even a number of lugs equal to the number of teeth of the toothed wheel. According to another variant, the toothed wheel and the crown head could form one and the same one-piece component. According to yet another variant, the lugs could be integral with the disk51and cooperate with an opening of crenelated shape formed in the case middle.

Lastly, the control device1also comprises a retaining means9that cooperates with a retaining surface58of the crown head to limit the movement in translation of the crown head parallel to the axis of rotation X. In this case, the retaining means9is formed by a retaining screw which is integral with the body4and which passes through an opening59in the crown head. The retaining screw extends parallel to the axis of rotation X and is centered on this axis of rotation. It cooperates with a tapped opening413provided at the center of the body4. The retaining screw comprises a screw head91forming a stop that cooperates with the retaining surface58to prevent the crown head from decoupling from the body4.

According to one embodiment variant, the control device1might not comprise such a retaining means since the cooperation of the locking element with the formation47B already provides a first means for retaining the crown head on the body. In such a scenario, the diameter of the second wall411could be increased slightly, at least at a portion414of the second wall that is comprised between the formation47B and the edge of this second wall. In such a scenario, the crown head could be assembled with the body4by forcing the retaining element6into an interference fit with the portion414and/or by heating or cooling the crown head5or the body4, respectively. Advantageously, the force required to force the retaining element6into the portion414would then be far greater than that which is conventionally applied by a user to move the crown head from its first position to its second position, and this would prevent unintended decoupling of the crown head.

The timepiece may advantageously comprise a first mechanism, notably a mechanism for rewinding the barrel, and a second mechanism, notably a mechanism for adjusting the time. The body4may be connected directly or indirectly to the first mechanism such that the first mechanism is activated when the crown head is rotated in a first direction of rotation. The body4may be connected directly or indirectly to the second mechanism such that the second mechanism is activated when the crown head is rotated in a second direction of rotation, opposite to the first direction of rotation. The visible face of the disk51may thus comprise informative or esthetic designs such as arrows indicating that the crown head can be actuated in two opposite directions of rotation.

It should be noted that the disk51may also comprise an outer periphery provided with a design such as a set of slots in order to improve the grip of the fingers on the crown head. According to one embodiment variant, the rotation prevention means57could be formed by the set of slots that are arranged on the outer periphery of the disk51, and not by the toothed wheel that is arranged on the lower face of the disk. Thus, the manufacturing method of the control device could be facilitated.

During use of the timepiece, when the crown head is in its first position, the latter is prevented from rotating by virtue of the cooperation of the rotation prevention means57with the two lugs23of the case middle2. Consequently, no sliding action is produced at the interface between the locking element6and the body4, and the locking element6is not subjected to wear. There is no risk of the crown head pivoting due to an undesired manipulation, said crown head can therefore maintain a given position, this making it possible to optimize the overall esthetic of the timepiece. Lastly, in this position, the body4is uncoupled from the crown head5and may possibly rotate freely about the axis of rotation X, without driving the crown head in rotation. The element3of the first mechanism may therefore also rotate about the axis of rotation X.

To pass from the first position to the second position, the user of the timepiece grasps the disk51and pulls it parallel to the axis of rotation X. The rotation prevention means57disengages from the lugs23. This makes it possible to rotate the crown head. The first and second coupling means are positioned opposite one another. The crown head5then rotates conjointly with the body4. It should be noted that in the situation in which the first set of splines has not been positioned correctly facing the second set of splines, a rotation of the crown head with respect to the body may be required. The smaller this rotation, the greater the number of splines making up the first and second sets of splines. The ends of the splines may be beveled in order to facilitate the engagement of the splines. If the body4remained immobile while the crown head was in its first position, the first set of splines is automatically aligned with the second set of splines.

Once the crown head is in its second position, the first and second coupling means cooperate in such a way as to secure the crown head to the body4for conjoint rotation. To rewind the barrel or adjust the time, the user rotates the crown head in one direction or the other about the axis of rotation X, which drives the element3in rotation. Owing to the coupling between the crown head and the body, no relative rotational movement between these two components is produced. Consequently, the locking element is not subjected to any load linked to sliding thereof against the body4and it is not subjected to wear.

Lastly, when the user has finished rotating the crown head, they can push on said crown head so as to make it resume its first position. In so doing, the first and second coupling means uncouple. A slight rotation of the crown may possibly be required so that the lugs23sit between two adjacent teeth of the rotation prevention means57.

The invention makes available a control device, the crown head of which is movable between a position uncoupled from, and a position coupled to, the body. By virtue of the cooperation of the locking element with the first and second formations, the two positions of the crown head are stable positions. When the crown head is actuated in rotation, the locking element does not slide with respect to the body. Consequently, no wear of the locking element occurs as the control device is being used. The stability of the first and second positions of the crown head is thus maintained throughout the life of the timepiece. Moreover, the control device thus obtained is particularly compact. It can easily be integrated into smaller timepieces.