CH720984A1 - Control mechanism for a clockwork part - Google Patents

Abstract

The invention relates to a control mechanism (1) for a timepiece, comprising: – a control stem (3) extending along an axis and arranged to be operable in rotation about said axis as well as in translation along said axis between three stable axial positions; – a sliding pinion (23) integral in rotation with said control stem (3) and arranged to be movable in translation along said control stem (3) and to cooperate with a first control pinion; – a pivotally mounted pull-out (11) and arranged to cooperate with said control stem (3) and to be able to adopt three stable angular positions depending on the axial position of said control stem (1); – a first lever (13) pivotally mounted and arranged to be angularly controlled by said pull-out (11) and to axially position said sliding pinion (23) on said control stem (3); – a second rocker (33) pivotally mounted and arranged to be controlled and pivotally positioned by said first rocker (13), said second rocker (33) carrying a sliding pinion (35) comprising a second control pinion (37) arranged to mesh with said sliding pinion (23) in at least one of said stable axial positions of said control rod (3).

Description

Technical field

[0001] The present invention relates to the field of watchmaking. It relates, more particularly, to a control mechanism arranged to control a plurality of functions, such as the manual winding of a main or auxiliary barrel, the setting of the time, the correction of an additional mechanism such as a date mechanism, the setting of an alarm, the setting of a rotating scale or the like.

State of the art

[0002] A large number of types of control mechanisms have been proposed, with the aim of allowing a control stem to be connected to a plurality of functions of a watch. The most common type nowadays comprises a stem which is movable in rotation as well as in translation relative to its main axis. Depending on the axial position of the stem, which can adopt a plurality of stable axial positions, a pull-rod system moves a sliding pinion mounted in translation on the stem to mesh either with a first pinion (typically a winding pinion kinematically connected to the ratchet of a barrel), or with a second pinion (typically a return in kinematic connection with the display members to perform the time setting).

[0003] When it is desired to control at least three functions, the complexity of the mechanism increases significantly, in order to selectively connect an additional kinematic chain to the control rod.

[0004] In these movements, the engagement and disengagement of the kinematic links is delicate, in order to properly control the penetrations between the teeth, which has a direct impact on the user's feeling as to the quality of the mechanism. It is particularly common for gears to be used to move mobiles, which results in having meshes at the bottom of the teeth. This results in difficult operation, lacking fluidity, with premature wear of the cogs.

[0005] This is all the more important when using bevel gears, which require even more precise positioning than in the case of conventional gears.

[0006] Documents CH703451 and EP1152303 disclose examples of such three-position control mechanisms.

[0007] The aim of the invention is to propose a control mechanism for a timepiece, in which reliable positioning is obtained for the mobiles which mesh selectively.

Disclosure of the invention

[0008] More specifically, the invention relates to a control mechanism for a timepiece, as defined by claim 1. This mechanism comprises: - a control stem extending along an axis and arranged to be maneuverable in rotation about said axis as well as in translation along said axis between three stable axial positions; - a sliding pinion integral in rotation with said control stem and arranged to be movable in translation along the latter and to cooperate with a first control pinion; - a pivotally mounted pull-out and arranged to cooperate with said control stem and to be able to adopt three stable angular positions depending on the axial position of said control stem; - a first pivotally mounted lever and arranged to be angularly controlled by said pull-out and to axially position said sliding pinion on said control stem; - a second pivotally mounted rocker and arranged to be controlled and pivotally positioned by said first rocker, said second rocker carrying a sliding mobile comprising a second control pinion arranged to mesh with said sliding pinion in at least one of said stable axial positions of said control rod, in particular in the second stable axial position of the latter.

[0009] Controlling the position of the sliding pinion along the control rod on the one hand, and the angular position of the second rocker by means of the first rocker on the other hand, ensures precise positioning of the sliding pinion and the second control pinion when they cooperate. In doing so, the penetration between the corresponding teeth of these two elements can be obtained in a precise, reproducible and reliable manner, without it being defined by a support at the bottom of the teeth. This is all the more interesting when said teeth are of the conical type, which require a relatively fine positioning tolerance, but the invention is however not limited to this form of teeth.

[0010] Advantageously, said first rocker cooperates with a pull spring in order to indirectly define said three stable axial positions of the control rod. In a particular embodiment, the pull spring may comprise notches which cooperate with a finger, a pin or the like carried by the first rocker, but an inverse configuration is also possible.

[0011] Advantageously, said sliding pinion comprises an additional toothing arranged to cooperate with said first control pinion, when said control rod is in its first stable axial position, said first control pinion being mounted loosely on said control rod, that is to say that said control rod cannot drive said first pinion in rotation directly. This additional toothing may in particular be on edge.

[0012] Advantageously, said sliding wheel comprises a sliding pinion integral in rotation with said second control pinion, said sliding pinion being arranged to mesh with a controlled wheel when said control rod is in its second stable axial position.

[0013] Advantageously, said second lever comprises: - a first stop arranged to cooperate with a first bearing surface with which said first lever is provided in order to move said second control pinion away from said sliding pinion when said control rod is in its first stable axial position; - a second stop arranged to cooperate with a second bearing surface with which said first lever is provided in order to move said sliding pinion away from said controlled mobile when said control rod is in its third stable axial position. In this state, it is immaterial whether the second control pinion is engaged with the sliding pinion or not; said mechanism further comprising a return spring arranged to bring said second control pinion into engagement with said sliding pinion when said control rod is in its second stable axial position. Preferably, the angular position of said second lever is defined in this state by the cooperation between said first stop and said first bearing surface, which makes it possible to precisely position the second lever and therefore the second control pinion.

[0014] Advantageously, said first stop and said second stop are located on either side of the axis of rotation of said second rocker, which represents a simple and compact solution.

[0015] Advantageously, said control mechanism further comprises a third control pinion arranged to mesh with said sliding pinion when said control rod is in its third stable axial position.

[0016] Advantageously, said control rod comprises a groove cooperating with said pull rod.

[0017] Advantageously, said sliding pinion comprises a groove in which an arm which said first rocker comprises is placed.

Brief description of the drawings

[0018] Other details of the invention will appear more clearly on reading the following description, given with reference to the appended drawings in which: – Figure 1 is an isometric schematic view of a control mechanism according to the invention in a first state, certain elements having been removed; – Figure 2 is a view similar to Figure 1, other elements having been removed to better show the cooperation of the control pinion and the first controlled mobile; – Figure 3 is a view similar to Figure 1, the mechanism being in its second state; and – Figure 4 is a view similar to Figure 1, the mechanism being in its third state.

Embodiments of the invention

[0019] It should be noted that it was not possible to illustrate all the elements of said mechanism 1 in a single figure in a clear manner. Consequently, some elements have been omitted from certain figures, as explained below. However, the set of figures allows the construction to be perfectly understood.

[0020] The mechanism comprises a control stem 3 arranged to pass through a wall of a case middle of a watch case (not shown) and to carry a crown (not shown) at its free end, which serves to allow manipulation by a user. This control stem 3 extends along an axis and is movable in rotation about said axis, as well as in translation along said axis between three stable axial positions, as will clearly appear later, each stable axial position of the control stem 3 defining a stable state of the mechanism 1.

[0021] Figures 1 and 2 illustrate the mechanism 1 in a first of three expected stable states. This state typically corresponds to position 0 of the control rod, i.e. the proximal position of the rod.

[0022] The control stem 3 carries a first control pinion 5 (visible exclusively in FIG. 2) which is mounted idly on a circular section section 24 that the control stem 3 comprises and meshes with a first controlled mobile 7 in said first state, to control a first function as described below. In the illustrated embodiment, the first control pinion 5 is a winding pinion, and the first controlled mobile 7 is a mobile in kinematic connection with a barrel (not illustrated) and arranged to be able to wind a mainspring housed inside the latter. However, the first control pinion can be arranged to control any other watch mechanism, of a type such as mentioned in the preamble.

[0023] The first control pinion 5 is integral in translation with the control rod 3 in the illustrated embodiment, but can alternatively be mounted sliding in translation on the control rod 3, so as to permanently mesh with the first controlled mobile 7.

[0024] A sliding pinion 23 is mounted so as to be movable in translation on a section 25 of non-circular section (in particular square, polygonal, oval, crenellated or similar) of the control rod 3 so as to be able to slide on the latter while remaining integral with it in rotation. In the state illustrated in FIGS. 1 and 2, in which the control rod 3 is in its first stable axial position, completely pushed in (hereinafter "first state"), the sliding pinion 23 cooperates with the first control pinion 5 by means of an additional edge toothing 27 extending in the direction of the latter in order to drive it in rotation, but other solutions are of course possible for making the first control pinion 5 integral in rotation with the control rod 3, whether directly or indirectly. The cooperation between the sliding pinion 23 and the first control pinion 5 is bidirectional in the illustrated embodiment, a de-clicking or reversing system being provided downstream in the case where the first control pinion 5 is used for winding a mainspring. Alternatively, the cooperation between the sliding pinion 23 and the first control pinion 5 can be obtained by a conventional Breguet toothing.

[0025] The control rod 3 comprises a groove 9 which cooperates with the free end of a pull rod 11 pivotally mounted on a frame element (not shown) about its axis of rotation 11a, its angular position thus being determined as a function of the axial position of the control rod 3.

[0026] The other end of the pull tab 11 is pivotally connected to a first lever 13 by means of a pin 12 (or alternatively by other suitable means), the first lever 13 also being pivotally mounted on a frame element about its own pivot axis 13a under the control of the pull tab 11. This first lever 13 comprises a finger 15 (or alternatively a pin or the like) which cooperates with a pull tab spring 17, which comprises a rigid portion 18 subjected to a restoring force provided by an elastic element 19 associated therewith. The latter serves to constrain the rigid portion 18 so as to cooperate with the finger 15. In another configuration not illustrated, the elastic element 19 is not integral with the rigid portion 18 of the pull tab spring 17, and is a separate element which cooperates with the rigid portion. Alternatively, it is also not necessary for the pull spring 17 to have a rigid portion 18, the pull spring 17 being able, for example, to comprise an elastic element having a shape adapted to cooperate with the finger 15 (or with another suitable structure, as mentioned below).

[0027] The rigid portion 18 of the pull spring 17 has three notches 21 to define three stable angular positions of the rocker 13, and consequently three stable axial positions for the control rod 3, by means of the pull 11. More generally, the pull spring 17 can have as many notches 21 as necessary to obtain the number of stable axial positions desired for the control rod 3. In an alternative configuration and not illustrated, the pull spring 17 can have a finger, a pin or the like, which cooperates with a plurality of notches provided on the first rocker 13.

[0028] The axial position of the sliding pinion 23 is controlled by an arm 29 of the rocker 13 and which takes place in a groove 31 which said pinion 23 comprises. When the rocker 13 pivots, the cooperation between this arm 29 and the groove 31 causes the sliding pinion 23 to slide along the section 25 of the control rod 3 in the direction opposite to that of the axial movement of the latter.

[0029] The mechanism also comprises a second lever 33, which carries a sliding wheel 35 comprising a second control pinion 37 integral in rotation with a sliding pinion 39, the operation of which will be described in detail in connection with FIGS. 3 and 4. The second lever 33 is movable in rotation about its own axis of rotation 33a, and comprises a first stop 41, here shown in the form of a pin, which cooperates with a first bearing surface (hidden by the second lever 33) that the first lever 13 comprises, in order to determine two of the stable angular positions of the second lever 33. In addition, the second lever 33 comprises a second stop 43, located on the opposite side of the axis 33a to the first stop 41, which cooperates with a second bearing surface (also hidden by the second lever 33) in order to define a third stable position for the second lever 33, as will be understood from the continued. The shape of the first rocker 13 is determined according to the needs of the manufacturer to cooperate with the two stops 41, 43 in the manner described, and its precise shape as illustrated is in no way limiting.

[0030] The second lever 33 is biased in the clockwise direction (according to the orientation of the figures) by a return spring 44, visible exclusively in FIG. 2. In the illustrated embodiment, this return spring 44 is a spiral spring, but a leaf spring or helical spring can also be used for the same purpose.

[0031] In the first state of the mechanism 1, the sliding wheel set 35 is kept out of engagement with the other wheel sets by the cooperation between the first stop 41 and the first bearing surface, against which the first stop 41 is kept in contact by the effect of the return spring 44. In doing so, the second control pinion 37 is out of engagement with the sliding pinion 23, while the sliding pinion 39 is out of engagement with a second controlled wheel set 45 mounted on a fixed bridge 47 and serving as a return to a second timepiece mechanism as mentioned in the preamble.

[0032] Finally, the mechanism 1 comprises a third control pinion 48, arranged to cooperate with the sliding pinion 23 when the mechanism is in its third state, as described below. This control pinion 48 meshes directly or indirectly with a third controlled mobile (not illustrated) associated with any third watch mechanism, as mentioned in the preamble.

[0033] In view of the above, it is clear that by pivoting the control rod 3 when the mechanism 1 is in its first state, only the first control pinion 5 will be actuated by the sliding pinion 23, the second control pinion 37 and the third control pinion 48 remaining stationary.

[0034] When the control rod 3 is in its second stable axial position, as illustrated in FIG. 3, the mechanism 1 is in its second state. To reach this state, the translation of the control rod 3 from its first to its second axial position has caused a rotation of the pull rod 11 about its pivot axis 11a, which has in turn caused the first rocker 13 to pivot counterclockwise (according to the orientation of the figures) about its pivot axis 13a, until its finger 15 has taken up position in the second notch 21 of the pull rod spring 17, which is the notch located in the middle of the three.

[0035] Following this angular movement of the first rocker, the sliding pinion 23 has been moved towards the distal end of the control rod 3 under the effect of the arm 29, which has caused the edge teeth 27 of the first control pinion 5 to disengage. A pivoting of the control rod 3 therefore no longer has any influence on the first control pinion 5, nor on the first controlled mobile 7.

[0036] At the same time, the first bearing surface has moved such that the second rocker 33 has been able to pivot sufficiently under the effect of the return spring 44 so that the toothed members 37, 39 of the sliding wheel 35 mesh with the sliding pinion 23 and the second controlled wheel 45 respectively, the return spring 44 ensuring the support of the first stop 41 on the first bearing surface. This support determines the penetration of the teeth between the toothed members 37, 39 of the sliding wheel 35 and the sliding pinion 23 and the second controlled wheel 45 respectively.

[0037] The sliding pinion 23 being still out of engagement with the third control pinion 48, the latter remains free and is not driven.

[0038] In this state, a pivoting of the stem will consequently drive the second control pinion 37, the second controlled mobile 45 as well as the clockwork mechanism which it controls.

[0039] Figure 4 illustrates the mechanism in its third state, with the control rod 3 having been pulled further to adopt its third stable axial position. Again, the axial displacement of the control rod 3 has caused the pull rod 11 to move angularly, which has consequently caused the first lever 13 to move into its third stable angular position, with the finger 15 now located in the third notch 21 of the pull rod spring 17.

[0040] The second bearing surface now cooperates with the second stop 43 so as to move the sliding wheel 35 away from the second controlled wheel 45, thereby breaking the meshing between the sliding pinion 39 and the latter. At the same time, the arm 29 has also moved the sliding pinion 23 along the section 25 so that said sliding pinion 23 now meshes with the third control pinion 48. In the illustrated embodiment, the sliding pinion 23 remains in mesh with the second control pinion 37, but it is also possible to arrange the mechanism so that the second lever 33 moves sufficiently counterclockwise to break this meshing.

[0041] In this state, the edge teeth 27 of the sliding pinion have moved further away from the first drive pinion 5 (not shown in FIG. 4).

[0042] Consequently, a pivoting of the stem when the mechanism 1 is in this state will cause a rotation of the third control pinion 48 to control the third associated clockwork mechanism, the first control pinion 5 being disengaged and the mobile 35 being driven empty.

[0043] When the user moves the control rod 3 axially back to its second axial position, the above-described movements are carried out in the opposite direction to return to the second state of the mechanism 1, and an additional axial movement of the control rod 3 will return the elements of the mechanism 1 to their initial state, i.e. that of FIGS. 1 and 2.

[0044] In the illustrated embodiment, the teeth of the sliding pinion 23, of the first sliding pinion 37 and of the third control pinion 48 are conical. This type of toothing implies relatively precise manufacturing and positioning tolerances, the latter being obtained by the support of the first stop against the first support surface of the first lever 13 when the sliding pinion 23 meshes with the second control pinion 37, and by the cooperation between the arm 29 of the intermediate lever 13 with the groove 31 of the sliding pinion 23. This relative positioning of these two toothed members is thus obtained in a deterministic and therefore precise manner, instead of being defined by a support at the bottom of the teeth.

[0045] However, the invention is not limited to this type of toothing for these toothed members. In particular, the sliding pinion 23 may have an edge toothing which cooperates with conventional or edge toothing provided on the second control pinion 37 and/or on the third control pinion 48. Alternatively, the sliding pinion 23 may have a conventional toothing which cooperates with edge toothing that the second control pinion 37 and the third control pinion 48 comprise.

[0046] Although the invention has been set forth with reference to a particular embodiment, variations are possible without departing from the scope of the appended claims.

Claims (12)

1. Control mechanism (1) for a timepiece, comprising: – a control stem (3) extending along an axis and arranged to be operable in rotation about said axis as well as in translation along said axis between three stable axial positions; – a sliding pinion (23) integral in rotation with said control stem (3) and arranged to be movable in translation along said control stem (3) and to cooperate with a first control pinion (5); – a pivotally mounted pull-out (11) and arranged to cooperate with said control stem (3) and to be able to adopt three stable angular positions depending on the axial position of said control stem (1); – a first lever (13) pivotally mounted and arranged to be angularly controlled by said pull-out (11) and to axially position said sliding pinion (23) on said control stem (3); – a second rocker (33) pivotally mounted and arranged to be controlled and pivotally positioned by said first rocker (13), said second rocker (33) carrying a sliding mobile (35) comprising a second control pinion (37) arranged to mesh with said sliding pinion (23) in at least one of said stable axial positions of said control rod (3). 2. Control mechanism (1) according to the preceding claim, wherein said first rocker (13) cooperates with a pull spring (17) in order to define said three stable axial positions of said control rod (3). 3. Control mechanism (1) according to one of the preceding claims, wherein said sliding pinion (23) comprises an additional toothing (27) arranged to cooperate with said first control pinion (5) when said control rod (3) is in its first stable axial position, said first control pinion being mounted loosely on said control rod (3). 4. Control mechanism (1) according to one of the preceding claims, in which said sliding wheel (35) comprises a sliding pinion (39) integral in rotation with said second control pinion (37), said sliding pinion (39) being arranged to mesh with a controlled wheel (45) when said control rod (3) is in its second stable axial position. 5. Control mechanism (1) according to the preceding claim, wherein said second rocker (33) comprises: – a first stop (41) arranged to cooperate with a first bearing surface with which said first rocker (13) is provided in order to move said second control pinion (37) away from said sliding pinion (23) when said control rod (3) is in its first stable axial position; – a second stop (43) arranged to cooperate with a second bearing surface with which said first rocker (13) is provided in order to move said sliding pinion (39) away from said controlled mobile (45) when said control rod (23) is in its third stable axial position; and wherein said control mechanism (1) further comprises a return spring (44) arranged to bring said second control pinion (37) into engagement with said sliding pinion (23) when said control rod (3) is in its second stable axial position, the angular position of said second rocker (33) being defined in this state by the cooperation between said first stop (41) and said first bearing surface. 6. Control mechanism (1) according to the preceding claim, in which said first stop (41) and said second stop (43) are located on either side of the axis of rotation (33a) of said second rocker (33). 7. Control mechanism (1) according to one of the preceding claims, further comprising a third control pinion (48) arranged to mesh with said sliding pinion (23) when said control rod (3) is in its third stable axial position. 8. Control mechanism (1) according to one of the preceding claims, in which said control rod (3) comprises a groove (9) cooperating with said pull rod (11). 9. Control mechanism (1) according to one of the preceding claims, in which said sliding pinion (23) comprises a groove (31) in which an arm (29) which is comprised by said first rocker (13) is placed. 10. Control mechanism (1) according to one of the preceding claims, wherein said sliding pinion (23) comprises a bevel gear arranged to cooperate with at least one other bevel gear (37, 39). 11. Clock movement comprising a control mechanism (1) according to one of the preceding claims. 12. Timepiece comprising a timepiece movement according to the preceding claim.