Member for controlling at least one function of a timepiece movement
Patent Information
- Application Number
- EP2023719764
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-04-21
- Filing Date
- 2023-04-17
- Publication Date
- 2025-02-26
- Estimated Expiration
- 2043-04-17
AI Technical Summary
Existing control members for watch movements do not consistently guarantee automatic return to a neutral position after activating functions like rapid correction, and they often require separate mechanisms for different functions.
A control member with a first tubular cam mounted around the central rod and a second tubular cam housed in the guide tube, which cooperate with a spring to ensure automatic return to the neutral position through inclined working surfaces, allowing for both rotational and translational movements to control multiple functions independently.
Ensures reliable automatic return to the neutral position after function activation and allows a single control member to manage two distinct functions, such as month correction and chronograph reset, enhancing operational efficiency and simplicity.
Smart Images
Figure 1.1
Abstract
Description
[0001] CONTROL BODY OF AT LEAST ONE FIRST FUNCTION OF A WATCH MOVEMENT
[0002] Technical field
[0003] The present invention relates to a control member for at least a first function of a watch movement, said control member comprising a crown comprising a head and a central stem secured to the head and intended to be secured to a control stem, and a guide tube with a longitudinal axis A in which said central stem is mounted to be movable at least in axial rotation along said axis A, the crown being arranged to occupy at least one non-pressed position in which said crown is movable in axial rotation in at least one direction between at least one neutral, stable angular position and at least one unstable angular actuation position in which said first function is capable of being actuated via the control stem.
[0004] The present invention also relates to a timepiece comprising at least one such control member.
[0005] State of the art
[0006] Such a control member is used for example in a timepiece described in application WO 2022 / 175002 filed by the applicant, said timepiece comprising in particular a month indicator mechanism, the first function being a month correction function. To actuate the month correction function, the control member, in the non-pressed position, is movable in axial rotation, for example through an angle of approximately 60°, in one direction between its central stable angular position and a first unstable angular actuation position, corresponding to a rapid correction of the month +1, and through an angle of approximately 60° in the other direction between its central stable angular position and a second unstable angular actuation position corresponding to a rapid correction of the month -1.
[0007] The timepiece described in application WO 2022 / 175002 also comprises a chronograph mechanism, the control member also being arranged to, in response to pressure, be movable in axial translation between its non-pressed position and a pressed position in which a second function is actuated, namely one of the chronograph functions, and more particularly the Reset or Flyback function. The control member automatically returns to its non-pressed position after the pressure on the control member is released, like a push-button.
[0008] When correcting the month, the return to the central stable angular position of the control member is ensured by a mechanism comprising a cam-heart kinematically linked to the control member and returned to its central position by a spring once the torque applied to the control member is released and the correction is carried out.
[0009] However, this mechanism is not always sufficiently effective to guarantee an automatic return of the control organ from one of its unstable correction positions to its stable central position.
[0010] The present invention aims to remedy this drawback by proposing a control member making it possible to guarantee its automatic return to a neutral position after having been pivoted into an unstable position to activate a function of a watch movement, such as rapid correction.
[0011] Another object of the present invention is to propose a single control member allowing rapid control of a first function by rotation of the control member with an automatic return to the neutral position, like a rapid control rod, and also allowing a second function, different from the first function, to be actuated by pressing on said control member with an automatic return to the non-pressed position, like a push button.
[0012] Disclosure of the invention
[0013] To this end, the invention relates to a control member for at least one function of a watch movement, said control member comprising a crown comprising a head and a central stem secured to the head and intended to be secured to a control stem, and a guide tube of longitudinal axis A in which said central stem is mounted to be movable at least in axial rotation along said longitudinal axis A, the crown being arranged to occupy at least one non-pressed position in which said crown is movable in axial rotation in at least one direction between at least one neutral, stable angular position and at least one unstable angular actuation position in which said first function is capable of being actuated via the control stem.
[0014] According to the invention, the control member comprises a device for automatically returning the crown from its actuating position to its neutral position comprising a first tubular cam mounted integrally around the central rod and a second tubular cam housed in the guide tube, mounted freely in axial translation on the central rod and arranged to be able to essentially slide axially in said guide tube and to cooperate with a spring provided in the guide tube, said first and second cams having working surfaces arranged to be in contact at least when the crown is in its neutral position, said working surfaces having a profile obtained by intersecting said first and second cams by at least one inclined plane on the axis A, so that an axial rotation of the first cam via a rotation of the crown in its actuating position causes, by cooperation of the working surfaces,an axial translation of the second cam compressing the spring, and that an axial translation of the second cam returned by the spring when the rotation in the actuating position ceases, causes, by cooperation of the working surfaces, an axial rotation of the first cam which automatically returns the crown to its neutral position.,
[0015] Thus, the invention makes it possible to guarantee the automatic return of the crown to its neutral position after having carried out a rapid command of a first function.
[0016] In a preferred embodiment, the central rod is also mounted to be able to move in axial translation in the guide tube, the crown also being arranged to, in response to pressure on said crown, be able to move in axial translation between its non-pressed position and a pressed position in which a second function distinct from the first function is capable of being actuated via the control rod, so that an axial translation of the first cam causes, by cooperation of the working surfaces, an axial translation of the second cam compressing the spring, and to return to its non-pressed position when the pressure on the crown ceases, an axial translation of the second cam returned by the spring causes, by cooperation of the working surfaces, an axial translation of the first cam which returns the crown to its non-pressed position.
[0017] Thus, the invention makes it possible to control two different functions, such as two functions of different complications, independent of each other, by means of a single control member, one of the functions being controlled by said control member in the non-pressed position, like a quick control stem, and the other of the functions being controlled by said control member in the pressed position like a push button.
[0018] According to a preferred embodiment, the first function is the month correction of a month indicator mechanism and the second function is the Reset or Flyback function of a chronograph mechanism.
[0019] The present invention also relates to a timepiece comprising at least one control member as described above.
[0020] Brief description of the drawings
[0021] Other characteristics and advantages of the present invention will appear on reading the following detailed description of an embodiment of the invention, given by way of non-limiting example, and made with reference to the appended drawings in which:
[0022] - figure 1 is a sectional view of the control member according to the invention, the crown of said control member being in the non-pressed and neutral position;
[0023] - figure 2 is an isometric view of the control member according to the invention;
[0024] - figure 3 is a schematic view of a control stem capable of being secured to the control member of the present invention, arranged to control a Reset or Flyback function of a chronograph mechanism and a month correction function of a month indicator mechanism, of a timepiece, the control member being in its non-pressed and neutral position;
[0025] - figure 4 is an isometric view of the automatic return device according to the invention;
[0026] - Figure 5 is an isometric view of the first female cam of Figure 4;
[0027] - Figure 6 is an isometric view of the second male cam of Figure 4;
[0028] - figures 7a, 7b and 7c are sectional views showing the control member with the crown respectively in its neutral unpressed position, in its unstable and unpressed angular actuation position, and in its pressed position.
[0029] Embodiments of the invention
[0030] With reference to Figures 1 to 3, the present invention relates to a control member 1 for at least one, and advantageously several different functions of a watch movement, said control member 1 comprising a crown 2 intended to be secured to a control stem 3 arranged to actuate said functions. The control member 1 is mounted on the caseband (not shown) of a watch case of a timepiece so that said crown 2 protrudes from said caseband. For this purpose, the control member 1 comprises a guide tube 4 intended to be fixed by screwing or driving into the caseband. The guide tube 4 may, preferably, have overall symmetry of revolution with respect to a longitudinal axis A constituting the axis of rotation, and also preferably the axis of translation, of the crown 2.
[0031] The crown 2 is arranged to occupy a non-depressed or rest position shown in FIG. 1, in which said crown 2 is movable in axial rotation in at least one direction between at least one neutral, stable angular position, and at least one unstable angular actuation position in which a first function is capable of being actuated via the control rod 3, said first function being for example a rapid correction function of a mechanism, the at least one unstable angular actuation position typically corresponding to a correction position of the mechanism.
[0032] Advantageously, the crown 2 is arranged to be movable in axial rotation in one direction between the neutral, stable angular position, defining a stable, preferably central, angular position, and a first unstable angular actuation position, and to be movable in axial rotation in the other direction between said neutral position and a second unstable angular actuation position. When the first function is a correction function of a mechanism, the first unstable angular actuation position typically corresponds to a first correction position of the mechanism, and the second unstable angular actuation position typically corresponds to a second correction position of the mechanism.
[0033] Advantageously, the crown 2 is movable in axial rotation over an angle less than 360°, preferably less than 180°, and more preferably less than or equal to 70° in each direction of rotation.
[0034] Furthermore, in a preferred embodiment, the crown 2 is also arranged to, in response to pressure on said crown 2, be movable in axial translation between its non-pressed or rest position shown in FIG. 1 and a pressed position in which a second function distinct from the first function, for example a function of a chronograph mechanism, is capable of being actuated via the control stem 3, and to return to its non-pressed or rest position when pressure on the crown 2 ceases.In the present description, the “rest position” or “not depressed” is defined with respect to the axial translational movement of the crown 2, the rest position or not depressed being then defined as a position that the crown takes when it is not subjected to an axial force or pressure, in which the first function is capable of being actuated, the rest position or not depressed designating the state in which the crown is found when it is not subjected to any force external to the caseband. The crown 2 comprises a head 6, an axial skirt 8 secured to the head 6 and a central stem 10 connected to the head 6 or secured to the latter. The assembly formed by the crown 2 and the central stem 10 has a symmetry of revolution around the axis A. The central stem 10 is mounted to move in axial rotation, and preferably in axial translation, along said longitudinal axis A in the guide tube 4.The head 6 and the skirt 8 are mounted to move around the guide tube 4 in rotation, and preferably in translation, along the axis A.
[0035] The central stem 10 is intended to be secured to the control stem 3 by means, for example, of a female drive square 12 fixed to the free end of the central stem 10 by screwing and into which a male square 14 (see figure 3) provided at the end of the control stem 3 is intended to fit. The square end of the control stem 3 is slid, during assembly of the movement in the case, into the female drive square 12 by its open face. Once fitted, the female square 12 of the crown 2 permanently drives the male square of the control stem 3 in rotation. In addition, in the preferred embodiment in which the crown 2 also functions like a pusher, the bottom of the drive square 12 can push the end of the control stem 3 in axial translation into the pressed-in position when pressure is exerted on the crown 2.The control rod 3 has its own return spring which holds its square end in the drive square 12 to return the control rod 3 to the rest position when the pressure is released. It is obvious that the drive of the control rod by a square can be replaced by a drive having another suitable shape, such as a triangle, two flats or another polygonal shape.
[0036] Thus, the crown 2, with the central stem 10, and the control stem 3 once mounted on the central stem 10, are always integral in movement (in rotation and in translation). They can be rotated around the axis A like a control stem and, in the preferred embodiment in which the crown 2 also functions like a pusher, they can be moved in axial translation along the axis A in a position pressed by a user in order to control two different functions of the timepiece, and more precisely functions of two different complications, as will be described in more detail below.
[0037] More particularly, the timepiece comprises a first complication, the first function being linked to this first complication and being able to be for example a rapid correction function of a mechanism, the unstable angular actuation position(s) corresponding to one or more correction positions of the mechanism. For example, the timepiece may comprise a month indicator mechanism or a chronograph mechanism, the first function being a month correction function, respectively at least one chronograph function such as the START / STOP function, the Reset or Flyback function, preferably the Reset or Flyback function. It is obvious that any other complication which could be corrected by a rapid rotation of the crown 2, such as a moon, can be used.
[0038] The timepiece may include a second complication, such as a chronograph mechanism, and the second function is one of the chronograph functions such as the START / STOP function, the Reset or Flyback function. Obviously, any other complication that could be corrected by pressing crown 2, such as the day or week, can be used.
[0039] For example, the timepiece may include a month indicator mechanism and a chronograph mechanism, the first function being a month correction function, the second function being one of the chronograph functions, preferably the Reset or Flyback function.
[0040] Any other suitable complication may be used.
[0041] In order to be able to control a first function via the control stem 3 by rotating the crown 2, and preferably a second function via said control stem 3 by pressing on the crown 2, the control stem 3 is arranged to be integral in rotation with a first device for actuating the first function, and to, preferably, be arranged to cooperate with a second device for actuating the second function when the crown 2 is moved into its pressed-in position, while being free in axial translation relative to the first actuating device. Details on such a control stem 3 are given in application WO 2022 / 175002.For this reason, it will simply be described here that the first actuating device comprises a return 16 mounted on the square 18 of the control stem 3, to be integral in rotation with said control stem 3 and preferably only able to slide relative to each other, said return 16 being arranged to actuate the first function, for example the month correction function of a month indicator mechanism. The return 16 moves, like the crown 2 and the control stem 3, between three angular positions, namely a first neutral position, a first unstable angular position for rapid correction, for example at +65° relative to the neutral position, corresponding to the addition of a month and a second unstable angular position for rapid correction, for example at -65° relative to the neutral position, corresponding to the removal of a month.In the example shown, the first actuating device also comprises a centering rocker 20 for the control rod 3 and a centering spring 22 for the control rod 3, arranged to act on a core 24 linked to the return 16, in order to reposition in particular the control rod 3 in the central position.
[0042] Advantageously, the control stem 3 also has a groove 26 and the second actuating device comprises a pull rod 28 pivotally mounted on an element of the frame, engaged in said groove 26 and arranged to actuate the second function, for example the Reset function of a chronograph mechanism, when pressure is applied to the crown 2 causing an axial translation of the control stem 3.
[0043] In the example shown, during a rapid rotation of the crown 2 and therefore of the control rod 3, the spring 22 and the centering rocker 20 act on the heart 24. As soon as the torque transmitted to the control rod 3 is released, the spring 22 and the centering rocker 20 act on the walls of the heart 24 to reposition it, in particular with the control rod 3, and therefore reposition the crown 2 in its central, stable neutral angular position.
[0044] According to the invention, the control member 1 comprises its own device for automatically returning the crown 2 from one of its unstable actuating positions to its stable neutral position. In the example shown, the device for automatically returning to the stable position integrated into the control member according to the invention is used to reinforce the device for automatically returning the control stem 3. But it is quite obvious that the device for automatically returning to the stable position integrated into the control member according to the invention can be provided alone, without any return device or equivalent provided in particular on the control stem.
[0045] Said automatic return device of the control member 1 comprises a first tubular cam 30, mounted integrally around the central rod 10 on the side of the base 10a of said central rod 10 integral with the head 6 of the crown 2, so that the first cam 30 rotates with the central rod 10 along the axis A when the crown 2, in its non-pressed position, is turned in one direction or the other. In the preferred embodiment in which the crown 2 also functions like a pusher, the first cam 30 is also moved in translation along the axis A with the central rod 10 when pressure is exerted on the crown 2.
[0046] The automatic return device also comprises a second tubular cam 32 housed in the guide tube 4, mounted free in axial translation on the central rod 10 and arranged to be able to slide essentially, or even solely, axially in said guide tube 4 while being guided mainly in axial translation in said guide tube 4, its rotation relative to said guide tube 4 being minimal, or even impossible, and to cooperate with a spring 34 provided in the guide tube 4, wound around the central rod 10 between the bottom of the guide tube 4 and the second cam 32.
[0047] With particular reference to Figures 4 to 6, the first cam 30 and the second cam 32 have, at their opposite ends, working surfaces 30a, 32a respectively arranged to be in direct contact with each other at least when the crown 2 is in its neutral position, as shown in Figures 1 and 7a, said working surfaces 30a, 32a having a profile obtained by cutting said first and second tubular cams 30, 32 by at least one plane inclined on the axis A, that is to say not perpendicular to the axis A.Thus an axial rotation of the first cam 30 along the axis A via a rotation of the crown 2 in one of the unstable actuating positions causes, by cooperation of the working surfaces 30a, 32a, an axial translation of the second cam 32 in the guide tube 4, compressing the spring 34, and an axial translation of the second cam 32 along the axis A brought back or pushed by the spring 34 when the rotation of the crown 2 in said actuating position ceases, causes, by cooperation of the working surfaces 30a, 32a, an axial rotation, in the opposite direction, of the first cam 30, and therefore of the central rod 10, which automatically brings and replaces the crown 2 in its stable neutral position.
[0048] Advantageously, the working surfaces 30a, 32a are in direct contact with each other, preferably over the entire cam profile when the crown 2 is in its neutral position.
[0049] Advantageously, the first cam 30 is a female cam and the second cam 32 is a male cam so that the second male cam 32 penetrates, and preferably fits, into the first female cam 30 when they are sufficiently close together, the working surface 32a at the end of the second male cam 32, opposite the first female cam 30, then being able to engage with the working surface 30a at the end of said first female cam 30.
[0050] Preferably, the working surface 30a of the first female cam 30 has a profile obtained by intersecting said first cam 30 by at least one inclined plane on the axis A at an angle preferably between |30°| and |45°|, in order to be able to obtain for example an opening angle of the first cam of 70° + / - 10°. The working surface 32a of the second male cam 32 preferably has a profile of complementary shape, so that the working surface 32a of the second male cam 32 can engage with the working surface 30a of the first female cam 30.
[0051] According to a preferred embodiment, the working surfaces 30a, 32a of the first and second cams 30, 32 have a profile obtained by cutting said first and second cams 30, 32 by two planes P1 and P2 inclined on the axis A and symmetrical with respect to said axis A, as shown in FIG. 7a.
[0052] Thus, the first cam 30 is preferably a female cam whose working surface 30a has a profile obtained by cutting said first cam 30 by two planes P1, P2 inclined on the axis A at an angle preferably between 30° and 45° for one, here P1, and preferably between -45° and -30° for the other, here P2, said planes P1 and P2 being symmetrical with respect to said axis A. The second cam 32 is a male cam whose working surface has a profile of complementary shape, so that the working surface 32a of the second male cam 32 can engage with the working surface 30a of the first female cam 30.
[0053] Preferably, the first cam 30 has, at its end opposite the second cam 32, a working surface 30a whose profile comprises, for example, two planes inclined on the axis A and symmetrical, giving this first cam 30 a cylindrical shape notched in a V. The first cam 30 has, at its end opposite the working surface 30a, a circular section 30b, perpendicular to the axis A, coming to bear on the base 10a of the central rod 10.
[0054] The second cam 32 has, at its end opposite the first cam 30, a working surface 32a whose profile comprises, for example, two planes inclined on the axis A and symmetrical, giving this second cam 32 a shape complementary to that of the first cam 30 given by the working surface 30a. The second cam 32 has, at its end opposite the working surface 32a, a bearing surface 32b arranged to be housed in the guide tube 4 and to cooperate with the spring 34 provided at the bottom of the guide tube 4.
[0055] The second cam 32 is arranged to be slidably housed in the guide tube 4 while being locked in rotation there.
[0056] For this purpose, the inner wall of the guide tube 4 typically has longitudinal grooves 36 shown in FIG. 4 and the bearing surface 32b of the second cam 32 has a circumference of a shape substantially complementary to said grooves, for example a polygonal circumference.
[0057] Advantageously, in the preferred embodiment in which crown 2 also functions as a pusher, spring 34 is also the spring which serves to return crown 2 from its pushed-in position to its unpushed position when the pressure exerted from outside the caseband on crown 2 ceases.
[0058] In fact, when pressure is exerted on crown 2, the first cam
[0059] 30 moved in translation along the axis A with the central rod 10 causes, by cooperation of the working surfaces 30a, 32a which preferably remain in contact over the entire cam profile, an axial translation of the second cam 32 in the guide tube 4 compressing the spring 34. An axial translation of the second cam 32 brought back or pushed by the spring 34 when the pressure exerted from the outside on the crown 2 ceases, causes, by cooperation of the working surfaces 30a, 32a thus remaining in contact, an axial translation of the first cam 30, and therefore of the central rod 10, which brings back and replaces the crown 2 in its unpressed position.
[0060] With reference to Figures 7a to 7c, the operation of the automatic rotary return device to the stable position integrated into the control member according to the invention is as follows.
[0061] When the crown 2 is in its non-depressed, and neutral position, the first and second cams 30 and 32 are positioned on the central rod 10 nested one inside the other so that their working surfaces 30a, 32a are in direct contact with one another, typically over the entire cam profile, as shown in Figure 7a.
[0062] In this position, when the crown 2 is turned in one direction or the other, in one of its unstable angular actuation positions, by an angle of ± 65° for example, to carry out a rapid correction of the month ±1, for example, the axial rotation of the crown 2 causes the axial rotation of the first cam 30 secured to the central rod 10, so that the working surface 30a of the first cam 30 pushes the working surface 32a of the second cam 32, which, blocked or essentially blocked in rotation in the guide tube 4, moves away from the first cam 30 by sliding along the central rod 10 towards the bottom of the guide tube 4, the bearing surface 32b of the second cam 32 compressing the spring 34 in the bottom of the guide tube 4, as shown in Figure 7b.
[0063] In parallel, the central rod 10, actuated in rotation by the crown 2, has driven the control rod 3 in rotation via the squares 12 and 14, so as to carry out the rapid correction requested in one direction or the other depending on the direction of rotation of the crown 2. When the rapid correction is completed and the user has released the crown 2, the torque transmitted to the central rod 10 to cause its rotation in the unstable actuation position ceases. The second cam 32, no longer being constrained by the first cam 30, is returned by the spring 34 by sliding along the central rod 10 in the direction of the first cam 30. Thus, the working surface 32a of the second cam 32, in engagement with the working surface 30a of the first cam 30, causes the latter to rotate in the opposite direction, and therefore the central rod 10, until the first and second cams 30, 32 fit together again.Rotating the central rod 10 in the opposite direction brought the crown 2 back into its neutral position, as shown in Figure 7a.
[0064] In the preferred embodiment in which crown 2 also functions as a pusher, when crown 2 is in its stable angular position, as shown in Figure 7a, it is possible to actuate a second function, for example resetting a chronograph mechanism by pressing crown 2.
[0065] During its axial displacement following pressure on the crown 2, the central rod 10 moves with it in axial translation the first cam 30, which, by remaining fitted with the second cam 32 blocked or essentially blocked in rotation in the guide tube 4, pushes it by making it essentially or even only slide in the guide tube 4, the bearing surface 32b of the second cam 32 compressing the spring 34 in the bottom of the guide tube 4, as shown in figure 7c.
[0066] In parallel, the central stem 10 in axial translation has moved the control stem 3 also in axial translation via the squares 12 and 14, so as to actuate the second function, for example the chronograph reset. After releasing the pressure on the crown 2 and therefore on the central stem 10, the second cam 32 pushed by the spring 34 slides in the guide tube towards the outside by itself pushing on the first cam 30, and therefore on the central stem 10, so that the central stem 10 and the crown 2 return to the unpressed position shown in FIG. 7a. The timepiece may comprise one or more control members of the invention, arranged to actuate different first and second functions, in particular functions of several complications.
[0067] The invention makes it possible to control at least one function of a watch movement by rotating a control member such as a rapid control stem, guaranteeing an automatic return to the neutral position, once the function has been activated.
[0068] In addition, the invention also advantageously makes it possible to control two different functions, in particular functions of different complications, independent of each other, by means of a single control member, one of the functions being controlled by said control member like a push button and the other of the functions being controlled by said control member like a quick control rod, the automatic return to the neutral position, once the function has been actuated being reliable and therefore guaranteed. The single control member combining control by rotation and control by pressure is a preferred embodiment of the invention, but it is obvious that the control member of the invention can be used only with the control by rotation, without push button function.
Claims
Demands 1. Control member (1) of at least one first function of a horological movement, said control member (1) comprising a crown (2) comprising a head (6) and a central rod (10) integral with the head (6) and intended to be integral with a control rod (3), and a guide tube (4) of longitudinal axis A in which said central rod (10) is mounted movable at least in axial rotation about said longitudinal axis A, the crown (2) being arranged to occupy at least one non-pressed position in which said crown (2) is movable in axial rotation in at least one direction between at least one neutral, stable angular position, and at least one unstable actuation angular position in which said first function is capable of being actuated via the control rod (3),characterized in that the control member (1) comprises an automatic return device for the crown (2) from its actuation position to its neutral position, comprising a first tubular cam (30) fixedly mounted around the central rod (10) and a second tubular cam (32) housed in the guide tube (4) mounted freely in axial translation on the central rod (10) and arranged to essentially slide axially in the guide tube (4) and to cooperate with a spring (34) provided in said guide tube (4), said first cam (30) and said second cam (32) having working surfaces (30a, 32a) arranged to be in contact at least when the crown (2) is in its neutral position, said working surfaces (30a, 32a) having a profile obtained by cutting said first and second cams (30, 32) by at least one inclined plane on the axis A,such that an axial rotation of the first cam (30) via a rotation of the crown (2) in its actuation position causes, by cooperation of the working surfaces (30a, 32a), an axial translation of the second cam (32) compressing the spring (34), and that an axial translation of the second cam (32) returned by the spring (34) when the rotation in the actuation position ceases, causes, by cooperation of the working surfaces (30a, 32a), an axial rotation of the first cam (30) which automatically returns the crown (2) to its neutral position.
2. Control member (1) according to claim 1, characterized in that the first cam (30) is a female cam whose working surface (30a) has a profile obtained by cutting said first cam (30) with at least one inclined plane on the axis A at an angle between |30°| and |45°|, the second cam (32) being a male cam whose working surface (32a) has a complementary shape profile.
3. Control member (1) according to one of the preceding claims, characterized in that the working surfaces (30a, 32a) of the first and second cams (30, 32) have a profile obtained by cutting said first and second cams (30, 32) by two planes (P1, P2) inclined on the axis A and symmetrical with respect to said axis A.
4. Control member (1) according to claim 3, characterized in that the first cam (30) is a female cam whose working surface (30a) has a profile obtained by cutting said first cam (30) with two planes (P1, P2) inclined on the axis A at an angle between -45° and -30° for one and between 30° and 45° for the other, symmetrical with respect to said axis A, the second cam (32) being a male cam whose working surface (32a) has a complementary shape profile.
5. Control member (1) according to one of the preceding claims, characterized in that the inner wall of the guide tube (4) has longitudinal grooves (36) and in that the second cam (32) includes a bearing surface (32b) housed in the guide tube (4) arranged to cooperate with the spring (34) provided at the bottom of the guide tube (4), said bearing surface (32b) having a perimeter of shape substantially complementary to said grooves (36).
6. Control member (1) according to one of the preceding claims, characterized in that the first function is a correction function of a mechanism and in that at least one unstable angular actuation position corresponds to a correction position of the mechanism.
7. Control member (1) according to any one of the preceding claims, characterized in that the ring (2) is arranged to be movable in axial rotation in one direction between the neutral, stable angular position and a first unstable actuation angular position, and to be mobile in axial rotation in the other direction between said neutral position and a second unstable actuation angular position.
8. Control member (1) according to the preceding claim, characterized in that the first function is a correction function of a mechanism and in that the first unstable angular actuation position corresponds to a first correction position of the mechanism, the second unstable angular actuation position corresponding to a second correction position of the mechanism.
9. Control member (1) according to any one of the preceding claims, characterized in that the central rod (10) is mounted to move axially in the guide tube (4), the crown (2) also being arranged so that, in response to pressure on said crown (2), it is movable axially between its unpressed position and a pressed position in which a second function distinct from the first function can be actuated via the control rod (3), such that an axial translation of the first cam (30) causes, by cooperation of the working surfaces (30a, 32a), an axial translation of the second cam (32) compressing the spring (34), and to return to its unpressed position when the pressure on the crown (2) ceases, an axial translation of the second cam (32) brought back by the spring (34), causing, by cooperation of the working surfaces (30a, 32a),an axial translation of the first cam (30) which returns the crown (2) to its unpressed position.
10. Control unit (1) according to the preceding claim, characterized in that the second function is one of the chronograph functions.
11. Control member (1) according to one of the preceding claims, characterized in that the central rod (10) has at its free end a female drive square (12) into which a male square (14) provided at the end of the control rod (3) is intended to fit. A timepiece comprising at least one control element (1) according to any one of claims 1 to 11. A timepiece according to claim 12, characterized in that it comprises a month indicator mechanism or a chronograph mechanism and in that the first function is a month correction function, or at least one chronograph function, respectively. A timepiece comprising at least one control element (1) according to any one of claims 9 to 11, characterized in that it comprises a month indicator mechanism and a chronograph mechanism and in that the first function is a month correction function, the second function being one of the chronograph functions. A timepiece according to claim 13 or 14, characterized in that the second function is the chronograph reset or flyback function.