CH717211A2 - Crown for timepiece case, stem for clockwork movement and timepiece. - Google Patents

Abstract

The invention relates to a crown (10) for a timepiece case comprising a first edge toothing (130) intended to cooperate with a second edge toothing (210) provided on a rod (2) for a watch movement. The teeth can be profiled to limit the torque transmitted.

Description

The invention relates to a crown for a timepiece case. The invention also relates to a stem for a timepiece movement. The invention also relates to a timepiece case comprising such a crown or a timepiece movement comprising such a stem. Finally, the invention relates to a watch system comprising such a crown or such a stem or such a watch movement or such a case.

[0002] FIG. 1 represents a sectional view illustrating a box 300 comprising a crown 10 screwed to a middle part 100, which is designed according to the knowledge of the prior art. FIG. 2 illustrates an exploded view along an axis A of such a ring. FIG. 3 represents, for its part, a sectional view illustrating the same box 100 on which the crown 10 is unscrewed. For simplicity, the seals have been removed from the illustrations.

The crown 10est intended to be screwed onto a tube 101previously fixed to the middle part 100. To do this, the crown 10 includes a cap 11, an inner portion of which comprises an internal thread 11a intended to cooperate with a threaded portion 101a of the tube 101 during the 'operation of screwing the crown 10. The crown 10 also comprises a tubular portion 12formed by a housing 120 within which is encapsulated a rod 2 of axis A', as well as a return spring 3 in the form of a spring helical.

[0004] A clutch device 40 for a clockwork crown comprises a ring 13 fixed to a longitudinal end of the tubular portion 12 of the crown 10, a shaft 21 fixed to a longitudinal end of the rod 2, as well as the return spring 3. The ring 13 comprises a bearing surface 13a more particularly visible in FIG. 3, as well as a portion 13b of non-circular section more particularly visible on the exploded view of FIG. 2. The shaft 21 comprises, for its part, a bearing surface 21a more particularly visible in Figure 3, as well as a portion 21b of non-circular section more particularly visible on the exploded view of Figure 2.

In the screwed crown configuration (shown in Figure 1), the elements 13 and 21 are kept out of reach. In this configuration, the rod 2 has an axial position defined by a clockwork movement 200, while the crown is here positioned axially by its cap 11, which cooperates with the tube 101. This is made possible by the spring 3 which confers a degree in translation to the crown 10relative to the rod 2 during the screwing operation.

[0006] FIG. 3 represents the crown 10 once unscrewed from the tube 101. In this configuration, the elements 13 and 21 are engaged under the effect of the elastic restitution of the spring 3. More particularly, the bearing surfaces 13a and 21a are in contact, this which makes it possible to secure the crown and the stem in translation, in particular towards the outside of the middle part 100. The portion 13b of non-circular section of the ring 13 is also threaded on the portion 21b of non-circular section of the shaft 21 , which makes it possible to secure the crown and the rotating rod.

In the particular embodiment of Figures 1 to 3, the portions 13b and 21b respectively of the components 13 and 21 each have a hexagonal geometry. These portions cooperate in a plane transverse to the crown or to the rod, namely a plane perpendicular to the axis A or to the axis A '. Thus, during the engagement of the ring 13 on the shaft 21, there is a risk of jamming or "scratching" which is explained by a potential bracing of the portions 13b and 21b before the hexagonal geometries align. and coincide, and thus make it possible to engage the ring 13 on the shaft 21.

[0008] The aim of the invention is to provide a crown for a timepiece case or a stem for a timepiece movement making it possible to overcome the drawbacks mentioned above and to improve crowns and stems known from the prior art. In particular, the invention proposes a horological crown and / or a horological stem allowing a free engagement between the crown and the stem. In addition, the invention proposes a watch crown and / or a watch stem making it possible to integrate a torque limiting function in the clutch between the crown and the stem.

A crown for a timepiece case according to the invention is defined by claim 1.

Different embodiments of crowns are defined by claims 2 to 6.

A stem for a timepiece movement according to the invention is defined by claim 7.

Different embodiments of rods are defined by claims 8 to 11.

A timepiece case according to the invention is defined by claim 12.

A timepiece movement according to the invention is defined by claim 13.

A timepiece system according to the invention is defined by claim 14.

[0016] One embodiment of a watch system is defined by claim 15.

The accompanying drawings show, by way of examples, a clock system known from the prior art and embodiments of a clock system according to the invention. Figures 1 to 3 are views of a system known from the prior art. FIGS. 4 to 7 are views of a first embodiment of a watch system. FIG. 8 is a view of a second embodiment of a timepiece system. FIG. 9 is a graph representing the changes in torque at the level of a crown as a function of the angle of rotation of this crown.

A first embodiment of a clock system 150est described below with reference to Figures 4 to 7.

The horological system 150est for example a timepiece 400, in particular a watch, in particular a wristwatch.

The watch system preferably comprises a box 300de timepiece. The watch system further comprises a watch movement 200. The watch movement is intended to be mounted in the timepiece case in order to protect it from the external environment.

The timepiece case 300 preferably comprises a middle part 100 and a crown 10 provided with a first edge toothing 130. The timepiece case 100 also preferably includes a back cover attached to the middle part and a crystal attached to the case. the build. The crown is mounted to be movable in rotation relative to the rest of the timepiece case 300, around an axis A of the crown.

The watch movement can be an electronic movement or a mechanical movement, in particular an automatic movement. The watch movement comprises a rod 2mitted with a second toothing 210de song. The stem 2 can conventionally be a winding and / or time-setting stem. Additionally, this rod can be provided to perform various adjustments of the timepiece, for example the adjustment of a calendar, in particular of an annual, semi-perpetual, or even perpetual calendar. Alternatively, this rod can be provided for winding and / or setting an alarm clock or a ringtone of any type. The rod can also be provided to activate any other function by rotation about its axis. The rod is mounted to be able to rotate relative to the rest of the watch movement, around an axis A ′ of the rod. Preferably, the axes A and A 'are merged or substantially merged.

Advantageously, the watch system comprises a spring 3de return the first toothing to a position of cooperation with the second toothing. Also advantageously, the crown comprises a thread 11a, in particular an internal thread, provided to cooperate with a thread 101a, in particular an external thread, on the middle part, in particular on a tube 101 brought onto the middle part, to keep the crown screwed on the middle part. . Thus, when the crown is unscrewed, the teeth 130 and 210 are resiliently biased against each other under the effect of the helical spring 3disposed in a housing 120 of a tubular part of the crown 10.

The set of first and second teeth constitutes a clutch device for a clockwork crown, in particular for a screwed crown. Such a device makes it possible to disengage the winding and / or time-setting stem of the crown when the latter is being screwed against the middle part, in particular to avoid actuation, in particular an overvoltage, of the crown. barrel spring during this operation. Advantageously, the clutch device is shaped so as to optimize the sensations when screwing and / or unscrewing the crown. Again advantageously, this clutch device can also constitute a torque limiting device when the torque of the rod reaches a predefined threshold value, in particular during the reassembly of the movement or during an operation to adjust the part of the rod. watchmaking.

FIG. 4 represents an exploded view of the crown along the axes A, A '. FIG. 5 represents a sectional view of the case 300 comprising the crown 10, in a screwed configuration of the crown. FIG. 6 represents, for its part, a sectional view of the case 300 comprising the crown 10, in a configuration unscrewed from the crown. For simplicity, the seals have been removed from the illustrations. The references of Figures 1 to 3 are also repeated for parts providing the same functions as those described on the basis of Figures 1 to 3.

The crown 10 includes the first edge teeth 130 intended to cooperate with the second edge teeth 210prévue on the rod 2du watch movement 200.

The rod 2 includes a second edge toothing 210destined to cooperate with the first edge toothing 130prévue on the crown 10de the box 300de timepiece 400.

Preferably, the first toothing 130 comprises a first dog element. In other words, the first set of teeth comprises at least a first tooth 130a, in particular first teeth 130a separated by first hollows 130d and having first flanks 130b oriented at least substantially along the axial and radial planes of the crown. The first toothing is, for example, produced on a ring 13repportée on the crown, in particular driven into a bore of the crown.

[0029] Preferably, the second toothing 210 comprises a second dog element. In other words, the second toothing 210 comprises second teeth 210a separated by second hollows 210d and having second flanks 210b oriented at least substantially along axial and radial planes of the rod. The second set of teeth is, for its part, arranged on a shaft 21disposed at one end 2a of the rod. For example, the end 2a of the rod is threaded and screwed into an axial thread provided in the shaft 21.

The first and second teeth extend in the longitudinal direction of the rod, that is to say along the axis A or A '. The crown 10 and the rod 2 thus form a 40vertical clutch device in the longitudinal direction of the rod.

The first toothing 130 comprises at least one tooth 130a. In the example of Figures 4 to 7, the teeth 130a are in the form of crenellations. The flanks 130b of the teeth 130a extend in the direction of the axis A, or substantially in the direction of the axis A. Thus, the directions normal to these flanks are oriented orthoradially or substantially orthoradially relative to the axis A.

The second toothing 210 comprises at least one tooth 210a. In the example of Figures 4 to 7, the teeth 210a are in the form of crenellations. The sides 210b of the teeth 210a extend in the direction of the axis A ', or substantially in the direction of the axis A'. Thus, the directions normal to these flanks are oriented orthoradially or substantially orthoradially relative to the axis A ′.

Preferably, the first teeth 130a are evenly distributed around the axis A of rotation.

Preferably, the second teeth 210a are evenly distributed around the axis A 'of rotation.

Preferably, the ends or heads 130c of the first teeth 130a have a first protruding profile, in particular a first rounded protruding profile or a first protruding profile at a point or triangular.

Preferably also, the ends or heads 210c of the second teeth 210a have a second projecting profile, in particular a second rounded projecting profile or a second projecting profile in a point or triangular.

In Figures 4 and 7, the ends of the first and second teeth are shown rounded.

The conformation of the teeth 130et 210, in particular the conformation of the ends 130c and 210c makes it possible to facilitate the engagement of the first and second teeth, thus optimizing the function of the clutch device 40.

The first toothing 130 comprises, for example, between two and eight first teeth 130a, in particular between four and six first teeth 130a. In the first embodiment shown, the first set of teeth comprises four teeth.

The second set of teeth comprises, for example, between two and eight second teeth, in particular between four and six second teeth. In the first embodiment shown, the second set of teeth comprises four teeth.

The first and second teeth can include the same number of teeth. Alternatively, the first and second teeth can have different numbers of teeth. For example, the number of teeth of the first set of teeth can be a multiple of the number of teeth of the second set of teeth or vice versa.

Advantageously, the first toothing is arranged around an opening 13c for receiving the rod 2.

A second embodiment of a clock system 400est described below with reference to Figure 8.

Preferably, this second embodiment differs from the first embodiment only by the geometries of the first and second teeth. Thus, only the first and second teeth are shown in Figure 8.

Advantageously, the first toothing 130 comprises first teeth 130a having first flanks 130b forming a first angle α between 0 ° and 45 °, or even between 10 ° and 30 °, with the axis A of rotation of the crown . In other words, the directions normal to these flanks are oriented by forming the angle α with the orthoradial direction.

Advantageously, the second toothing 210 comprises second teeth 210a having second flanks 210b forming a second angle β between 0 ° and 45 °, or even between 10 ° and 30 °, with the axis A 'of rotation of the rod. In other words, the directions normal to these flanks are oriented by forming the angle β with the orthoradial direction.

Preferably, the angles α and β are equal.

Advantageously, a conformation of the teeth 130 and 210 with a non-zero angle α or β and beyond a threshold defined by the coefficient of friction between the teeth allows the clutch device to implement a function of limiting torque at the crown. Indeed, the flanks 130b and 210b of the teeth 130a and 210a are then not parallel to the axes A, A '. For example, the teeth 130a and 210a can have geometries of triangular or substantially triangular shape as shown in FIG. 8. Thus, the heads 130c and 210c respectively of the teeth 130a and 210a can be limited to an edge or to a point surface, even very punctual, facing the flanks 130b and 210b.

The teeth shown in Figure 8 are shaped so as to transmit a torque C of rotation to the rod not exceeding a certain value, for example a value of the order of 0.01Nm.

FIG. 9 illustrates a graph representing the torque value at the crown 10 according to the angle α of rotation traversed by the crown. Thanks to this graph, it can be seen that the device 40 does indeed constitute a torque limiting device. Indeed, when the torque reaches approximately 0.01Nm, the sides of the teeth slide over each other, the spring 3 is compressed under the effect of sliding and the teeth of the teeth emerge from the hollows where they are located to join the following hollows.

Whatever the embodiment, with the exception of the conformation of certain elements of the clutch device 40, the components involved in the crown 10 according to the invention are preferably generally the same as those involved in the within a ring known from the prior art, such as that illustrated by Figures 1 to 3. Due to the conformation of the toothing 210 on the shaft 21, a washer 22 (more particularly visible in Figures 5 and 6) is arranged between the toothing 210et the spring 3 so that the latter can ensure the axial retention of the spring.

FIG. 5 represents the crown 10 in a configuration screwed onto the middle part 100, in particular on the tube 101. In this configuration, the ring 13 is out of reach of the teeth 210 of the shaft 21.

FIG. 6 represents the crown 10 in an unscrewed configuration. In this configuration, the toothing 130de the ring 13 is engaged with the toothing 210de the shaft 21, which allows the rotational coupling of the rod and the crown. In this configuration, the respective surfaces 13a, 21a of the components 13 and 21 are in particular in contact, which makes it possible to secure the crown and the stem in translation, in particular towards the outside of the middle part 100.

In this configuration, the teeth cooperate in a plane transverse to the rod, namely a plane perpendicular to the axis A or to the axis A '. Nevertheless, the engagement of the teeth 130 and 210 takes place in a direction parallel to the axis A or to the axis A 'or substantially parallel to the axis A or to the axis A'. These teeth, extending in the longitudinal direction of the stem, thus make it possible to facilitate the engagement of the crown and the stem, and thus to optimize the sensations to the stem when unscrewing the crown.

In other words, the clock system 400 is in the form of a dog clutch, namely a device comprising two parts whose teeth extend in the longitudinal direction of the rod or the crown.

The solutions described above make it possible to improve the clutch systems of crowns, in particular of screwed crowns. In particular, the solutions described make it possible to guarantee a “direct” engagement of the stem and the crown regardless of the angular position of the latter. This limits the risk of “scratching” perceptible by the user of the timepiece.

In addition, the solutions described make it possible to limit the torque of the crown. They synergistically improve crown clutches so as to limit scratching and provide a torque limiting function. Moreover, this function of limiting the torque to the crown is of great interest with regard to certain functions for adjusting the movement.

The solutions described allow both the axial disengagement of the crown facing the rod when the latter is screwed, but also the disengagement of the crown beyond a certain value of torque of the rod. , for example during winding or when adjusting the timepiece. The sensations when screwing or unscrewing the crown are also improved.

In the particular embodiment of Figures 1 to 3, the portions 13b and 21b respectively of the components 13 and 21 each have a hexagonal geometry. These portions cooperate in a plane transverse to the crown or to the rod, namely a plane perpendicular to the axis A or to the axis A '. Thus, during the engagement of the ring 13 on the shaft 21, there is a risk of jamming or "scratching" which is explained by a potential bracing of the portions 13b and 21b before the hexagonal geometries align. and coincide, and thus make it possible to engage the ring 13 on the shaft 21.

Thanks to the solutions described above, the inconveniences identified in the prior art and consisting of jamming or "scratching" which are explained by a potential arching of the portions 13b and 21b before the hexagonal geometries s' align and coincide, and thus make possible the engagement of the ring 13 on the shaft 21, are avoided by providing a ring 13, as well as a shaft 21, each provided with teeth extending in a longitudinal direction of the rod. By "longitudinal direction" we mean a direction parallel to the axis A of rotation of the crown or a direction parallel to the axis A 'of rotation of the rod.

Claims (15)

1. Crown (10) for a case (300) of a timepiece (400), comprising a first edge toothing (130) intended to cooperate with a second edge toothing (210) provided on a rod (2) for a watch movement (200). 2. Crown according to claim 1, characterized in that the first toothing (130) comprises a first dog element or in that the first toothing comprises at least a first tooth (130a), in particular first teeth (130a) separated by first hollows (130d), the first tooth or teeth having first flanks (130b) oriented at least substantially along axial and radial planes of the crown. 3. Crown according to claim 1, characterized in that the first toothing (130) comprises at least a first tooth (130a), in particular first teeth (130a), having first flanks (130b) forming a first angle (α) ) between 0 ° and 45 °, or even between 10 ° and 30 °, with an axis (A) of rotation of the crown and / or in that the first teeth (130a) are evenly distributed around the axis (A) rotation. 4. Crown according to claim 2 or 3, characterized in that the end (130c) of the at least one first tooth (130a) has a first projecting profile, in particular a first rounded projecting profile or a first profile projecting at a point or triangular. 5. Crown according to one of the preceding claims, characterized in that the first toothing is arranged around an opening (13c) for receiving a rod (2) for a watch movement. 6. Crown according to one of the preceding claims, characterized in that it comprises a first thread (11a) intended to cooperate with a second thread (101a) on a middle part (100) of a case (300) of a timepiece (400) to fix the crown to the middle part. 7. Rod (2) for a watch movement (200), comprising a second edge toothing (210) intended to cooperate with a first edge toothing (130) provided on a crown (10) for box (300) of part of watchmaking (400). 8. Rod according to claim 7, characterized in that the second toothing (210) comprises a second dog element or in that the second toothing (210) comprises at least one second tooth (210a), in particular second teeth ( 210a) separated by second hollows (210d), the second tooth or teeth having second flanks (210b) oriented at least substantially along axial and radial planes of the rod. 9. Rod according to claim 7, characterized in that the second toothing (210) comprises at least a second tooth (210a), in particular second teeth (210a), having second flanks (210b) forming a second angle (β) ) between 0 ° and 45 °, or even between 10 ° and 30 °, with an axis (A ') of rotation of the rod and / or in that the second teeth (210a) are evenly distributed around the axis (A ') of rotation. 10. Rod according to claim 8 or 9, characterized in that the end (210c) of the at least one second tooth (210a) has a second protruding profile, in particular a second rounded protruding profile or a second protruding profile at a point or triangular. 11. Rod according to one of claims 7 to 10, characterized in that the second toothing is arranged on a shaft (21) disposed at one end (2a) of the rod. 12. Case (300) for a timepiece (400) comprising a crown according to one of claims 1 to 6. 13. Watch movement (200) comprising a stem (2) according to one of claims 7 to 11. 14. Watch system (150), in particular timepiece (400), in particular watch or wristwatch, comprising a crown (10) according to one of claims 1 to 6 and / or a case (300) of a timepiece. according to claim 12 and / or a rod (2) according to one of claims 7 to 11 and / or a movement according to claim 13. 15. Watch system (150) according to the preceding claim, characterized in that: - the watch system comprises a spring (3) for returning the first toothing (130) to a position of cooperation with the second toothing (210), and / or - the first toothing (130) comprises at least a first tooth (130a), in particular first teeth (130a), having first flanks (130b) forming a first angle (α) with an axis (A) of rotation of the crown and the second set of teeth (210) comprises at least one second tooth (210a), in particular second teeth (210a), having second flanks (210b) forming a second angle (β) with an axis (A ') of rotation of the rod, the first angle and the second angle being equal or substantially equal.