Device for setting a clock movement to time

Abstract

The invention relates to a time-setting device (10) for a watch, comprising a winding stem (11) configured to occupy a time-setting position in which it is engaged with a time-setting gear train (20) kinematically connected to a time display (30) and to a 24-hour wheel (31), the 24-hour wheel (31) being engaged with a barrel (40) intended to provide the energy necessary for displaying a time value, the barrel (40) comprising a ratchet mechanism (41) configured so as to allow rotation of the barrel (40) over more than one revolution when the winding stem (11) is rotated in a first direction, and so as to limit rotation of the barrel (40) to an angular amplitude corresponding to less than one revolution when the winding stem (11) is rotated in a second direction. sense.

Description

Technical field of the invention

[0001] The invention relates to the field of watchmaking and relates in particular to a device for setting the time of a watch. Technological background

[0002] The time setting devices of a watch are integrated into the watch movement of the watch and are well known to those skilled in the art.

[0003] For example, a commonly used time-setting device comprises one or more gears kinematically connecting a winding stem intended to be manipulated by a user to a minute wheel connected to a time display.

[0004] When the watch movement includes one or more watch complications, the time-setting device can be designed to meet a certain number of constraints.

[0005] The present invention fits within this framework. In particular, the present invention aims to eliminate any risk of damage to the watch movement when setting the time of the watch. Summary of the invention

[0006] The invention relates to a device for setting the time of a watch, comprising a winding stem configured to occupy a time-setting position in which it is engaged with a time-setting gear train kinematically connected to a time display and to a 24-hour wheel. The 24-hour wheel is engaged with a barrel comprising a barrel spring intended to provide the energy necessary for displaying a time value, the barrel comprising a ratchet mechanism configured so as to allow rotation of the barrel over more than one revolution when the winding stem is rotated in a first direction, and so as to limit rotation of the barrel to an angular amplitude corresponding to less than one revolution when the winding stem is rotated in a second direction.

[0007] In particular embodiments, the invention may further comprise one or more of the following features, taken individually or in any technically possible combination.

[0008] In particular embodiments, the time-setting gear train comprises a friction wheel configured to prevent the transmission of movement from the winding stem to the 24-hour wheel when said winding stem is rotated in the second direction and the barrel is forced into a stop position by the ratchet mechanism.

[0009] In particular embodiments, the time-setting gear train comprises a transmission wheel kinematically interposed between the friction wheel and the time display.

[0010] In particular embodiments, the transmission wheel is in meshing relationship with the 24-hour wheel and an hour wheel.

[0011] In particular embodiments, the barrel is configured such that the barrel spring is preloaded when the winding stem is rotated in the second direction and the ratchet mechanism prohibits rotation of the barrel.

[0012] In particular embodiments, the ratchet mechanism comprises a protrusion arranged on the barrel in an eccentric manner and extending parallel to the axis of rotation of the barrel, and a lever intended to cooperate with the protrusion so as to pivot the lever when the winding stem is rotated in the first direction, and so as to rest in abutment against said lever when the winding stem is rotated in the second direction.

[0013] In particular embodiments, the friction mobile comprises two wheels each arranged at one end of an axle comprising a board, one of the wheels, called the "first wheel", having a barrel applying a deformation force on an elastic member so as to force the latter to apply pressure on a flange so that the flange in combination with the board applies clamping forces on the other wheel, called the "second wheel".

[0014] In particular embodiments, the elastic member is constituted by a flat part in a rest state and curved in a stressed state.

[0015] In particular embodiments, the elastic member is formed by a disc having radial lobes on its periphery, intended to rest against the flange so as to ensure the rotational connection of said flange and the elastic member. Brief description of the figures

[0016] Other characteristics and advantages of the invention will appear on reading the following detailed description given by way of non-limiting example, with reference to the appended drawings in which: - there Figure 1 represents a perspective view of the kinematic chain of the time setting device according to a preferred example of embodiment of the invention; - the Figure 2 represents a sectional view of a friction wheel of a time setting device of the Figure 1 ; - there Figure 3 represents a perspective view from below of the kinematic chain of the time setting device of the Figure 1 .

[0017] Note that the figures are not necessarily drawn to scale for clarity. Detailed description of the invention

[0018] There Figure 1shows a time-setting device 10 of a watch, intended to be integrated into a watch movement of said watch. In the preferred embodiment of the invention shown in the figures and described in the present text, the time-setting device 10 is capable of setting both the time and the date of the watch.

[0019] The time-setting device 10 comprises a winding stem 11 on which a user of the watch is intended to act to set the time and possibly the date. In particular, the winding stem 11 is configured to occupy a time-setting position in which it is engaged with a time-setting gear train 20 kinematically connected to a time display 30 and to a 24-hour wheel 31. The time display 30 is constituted by hour and minute hands in the preferred embodiment of the invention.

[0020] The 24-hour wheel 31 is meshed with a barrel 40 comprising a barrel spring 40 intended to provide the energy necessary for displaying a time value, in particular the date. In particular, the 24-hour wheel 31 is meshed with a ratchet 401 of the barrel 40. The barrel 40 may be in accordance with that described in patent EP3540524. The watch movement may comprise another barrel intended to provide the energy necessary for rotating the time display 30.

[0021] The barrel 40 comprises a ratchet mechanism 41 configured so as to allow the rotation of the barrel 40 over an angular amplitude corresponding to more than one revolution when the winding stem 11 is rotated in a first direction, and so as to limit the rotation of the barrel 40 to an angular amplitude corresponding to less than one revolution when the winding stem 11 is rotated in a second direction.

[0022] Thanks to the characteristics of the invention, the user can set the time by moving the time display 30 in both directions of rotation, while avoiding the complete discharge of the barrel spring 40. Indeed, setting the time in the first direction has the effect of winding the barrel spring 40. Setting the time in the second direction therefore discharges the barrel spring 40, until the ratchet mechanism 41 blocks the rotation of the latter. It should be noted that when the ratchet mechanism 41 blocks the rotation of the barrel 40, the time display 30 is also immobilized.

[0023] In the preferred embodiment of the invention, the ratchet mechanism 41 comprises a protrusion 410, for example formed by a pin, arranged on the barrel 40 in an eccentric manner and extending parallel to the axis of rotation of the barrel 40. Thus, during rotation of the barrel 40, the protrusion 410 is driven along a circular trajectory centered on the axis of rotation of the barrel 40.

[0024] The ratchet mechanism 41 further comprises a lever 411, one end of which is arranged on the path of the protrusion 410, so that when the barrel 40 is rotated, the protrusion 410 cooperates with the lever 411. More precisely, the protrusion 410 causes the lever 411 to pivot when the winding stem 11 is rotated in the first direction, and it rests in abutment against said lever 411 when the winding stem 11 is rotated in the second direction. This latter case is shown in the Figure 1 .

[0025] When the rotation of the barrel 40 is blocked by the ratchet mechanism 41, that is to say when the protrusion 410 is arranged in abutment against the lever 411, a friction wheel 50 advantageously makes it possible to avoid any damage to the watch movement, and in particular to a component of the kinematic chain of the time-setting device 10. In particular, such damage is likely to occur if the winding stem 11 is driven in rotation in a second direction when the rotation of the barrel 40 is blocked.

[0026] As illustrated on the Figure 1 , the friction wheel 50 is arranged in the time-setting gear train 20 and is configured to prevent the transmission of movement from the winding stem 11 to the 24-hour wheel 31, when said winding stem 11 is rotated in the second direction and the barrel 40 is forced into a stop position by the ratchet mechanism 41.

[0027] In a preferred embodiment of the invention, the friction wheel 50, visible in sectional view on the Figure 2 , comprises a driven wheel 51 connected without a degree of freedom to one end of an axle 52, the axle 52 comprising a board 53 at its other end. The driven wheel 51 has a barrel 510 extending towards the board 53. The board 53 preferably has an annular shoulder 530 in which is housed a driving wheel 54 mounted free to rotate relative to said board 53. The driving wheel 54 is in meshing relationship with one of the references 21, as visible on the Figure 1 .

[0028] The friction wheel 50 also comprises a flange 55 fixed in rotation relative to the axis 52 and comprising an upper annular lip 550 oriented towards the driving wheel 54 and against which it rests, and a lower annular lip 551 extending axially and being oriented towards the driven wheel 51. Between the flange 55 and the driven wheel 51 is interposed an elastic member 56 through which the axis 52 extends and which is constrained by the lower annular lip 551 and the barrel 510.

[0029] In the preferred embodiment of the invention, the elastic member 56 is constituted by a flat part in a state of rest and curved in a stressed state. The elastic member is, for example, formed by a disc having radial lobes on its periphery, said lobes being intended to rest against the lower annular lip 551. The fact that the elastic member 56 is formed by a flat part in a state of rest in particular makes it easier to manufacture it and ensures that manufacturing tolerances are met. The lobes advantageously make it possible to distribute the mechanical stresses evenly. To facilitate the assembly of the friction wheel 50, a pin 57 can be engaged in corresponding holes in the board 53 and the flange 55 so as to ensure their rotational attachment.

[0030] The elastic member 56 is constrained so as to apply pressure to the lower annular lip 551 of the flange 55, causing the driving wheel 54 to be clamped between the upper annular lip 550 of the flange 55 and the plate 53. Thus, the driving wheel 54 transmits a rotational movement to the driven wheel 51, up to a certain friction torque beyond which the upper annular lip 550 and the plate 53 slide against the driving wheel 54. Such a friction torque is produced when the rotation of the barrel 40 is blocked by the ratchet mechanism 41 and the winding stem 11 is rotated in the second direction.

[0031] The constraint of the elastic member 56, and in particular of the disc having radial lobes, makes it possible to control the friction torque and to facilitate the manufacture and assembly of the friction mobile 50.

[0032] Furthermore, the interface surfaces of the board 53 and the driving wheel 54 advantageously have a beveled cross section, as does the interface surface of the lower annular lip 551 intended to receive the elastic member 56 in support. The particular arrangement of these surfaces makes it possible to better control the friction torque.

[0033] As visible on the figures 1 And 3 , the time-setting gear train 20 comprises a plurality of return wheels 21 making it possible to kinematically connect the winding stem 11 and the friction wheel set 50 together. The time-setting gear train 20 further comprises a transmission wheel set 60 kinematically interposed between the friction wheel set 50 and the time display 30. The transmission wheel set 60 is in meshing relationship with the driven wheel 51, for example by means of a return wheel, as visible in the Figure 1 .

[0034] As shown in the Figure 3, the transmission mobile 60 is in meshing relation with the 24-hour wheel 31, a cannon pinion 32 and an hour wheel 33, respectively by means of a 24-hour pinion 61, a minute wheel 62 and a minute pinion 63.

[0035] The barrel 40 is configured so that the barrel spring 40 is preloaded when the winding stem 11 is rotated in the second direction and the ratchet mechanism 41 prevents the barrel 40 from rotating. This feature makes it possible to avoid completely disarming the barrel spring 40, and thus to retain a certain amount of energy in the barrel 40. This preload makes it possible in particular to control the angular position of the barrel 40.

[0036] More generally, it should be noted that the methods of implementation and embodiment considered above have been described as non-limiting examples, and that other variants are consequently conceivable.

[0037] In particular, the driven wheel 51 and the driving wheel 54 may, in other embodiments of the invention, be reversed without this changing the operation of the friction wheel 50. In other words, the wheel called “driven wheel 51” in the present text and as shown in the Figure 2 could be driving and the wheel called “drive wheel 54” could be driven.

Claims

1. Time setting device (10) of a watch, characterized in that it comprises a winding stem (11) configured to occupy a time-setting position in which it is engaged with a time-setting gear train (20) kinematically connected to a time display (30) and to a 24-hour wheel (31), the 24-hour wheel (31) being engaged with a barrel (40) comprising a barrel spring (40) intended to provide the energy necessary for displaying a time value, the barrel (40) comprising a ratchet mechanism (41) configured so as to allow rotation of the barrel (40) over more than one revolution when the winding stem (11) is rotated in a first direction, and so as to limit rotation of the barrel (40) to an angular amplitude corresponding to less than one revolution when the winding stem (11) is rotated in a second direction.

2. Device according to claim 1, wherein the time-setting gear train (20) comprises a friction wheel (50) configured to prevent the transmission of movement from the winding stem (11) to the 24-hour wheel (31) when said winding stem (11) is rotated in the second direction and the barrel (40) is forced into a stop position by the ratchet mechanism (41).

3. Device according to claim 2, in which the time-setting gear train (20) comprises a transmission wheel (60) kinematically interposed between the friction wheel (50) and the time display (30).

4. Device according to claim 3, in which the transmission wheel (60) is in meshing relation with the 24-hour wheel (31) and an hour wheel (33).

5. Device according to one of claims 1 to 4, wherein the barrel (40) is configured so that the barrel spring (40) is preloaded when the winding stem (11) is rotated in the second direction and the ratchet mechanism (41) prevents rotation of the barrel (40).

6. Device according to one of claims 1 to 5, in which the ratchet mechanism (41) comprises a protrusion (410) arranged on the barrel (40) eccentrically and extending parallel to the axis of rotation of the barrel (40), and a lever (411) intended to cooperate with the protrusion (410) so as to pivot the lever (411) when the winding stem (11) is rotated in the first direction, and so as to rest in abutment against said lever (411) when the winding stem (11) is rotated in the second direction.

7. Device according to one of claims 2 to 4, in which the friction mobile (50) comprises two wheels (51, 54) each arranged at one end of an axle (52) comprising a board (53), one of the wheels (51, 54), called the "first wheel" (51), having a barrel (510) applying a deformation force to an elastic member (56) so as to force the latter to apply pressure to a flange (55) so that the flange (55) in combination with the board (53) applies clamping forces to the other wheel, called the "second wheel" (54).

8. Device according to claim 7, in which the elastic member (56) consists of a piece which is flat in a state of rest and curved in a stressed state.

9. Device according to claim 8, in which the elastic member (56) is formed by a disc having radial lobes on its periphery, intended to rest against the flange (55) so as to ensure the rotational connection of said flange and the elastic member (56).

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