Tourbillon or carousel mechanism for a timepiece movement

Abstract

The invention relates to a tourbillon or carousel mechanism (1) for a timepiece movement comprising: - a rotating cage (3) which is arranged to be rotated by a drive source (M); - a sprung-balance oscillator (7) carried by the rotatable cage (3); - an escapement (9) carried by the rotating cage (3) and arranged to co-operate with the oscillator (7) in order to keep it oscillating, the escapement (9) comprising an escapement wheel (11) which is mounted so as to pivot relative to the rotating cage (3) and rotates as one with an escapement pinion (15) which meshes with a toothing (17) carried by a frame element. According to the invention, the mechanism further comprises a member for indicating the fractions of a time division (23) kinematically connected to the escapement wheel (11).

Description

Description TWIST OR CAROUSEL MECHANISM FOR CLOCK MOVEMENT technical field

[0001] The present invention relates to the field of watchmaking. More particularly, it concerns a tourbillon or carousel mechanism for a watch movement. State of the art

[0002] Document EP0973076 reveals a tourbillon mechanism in which the cage carries a small seconds hand. This hand is driven by a linkage that meshes with the fixed wheel, and therefore, when the cage pivots, the hand pivots relative to the linkage since the linkage rolls on the fixed wheel.

[0003] This mechanism is certainly interesting, but since the small seconds hand is driven in this way, its rotation speed is limited, and the indication of fractions of seconds is not very precise, the angle traveled by the hand being very limited.

[0004] The aim of the invention is therefore to propose a tourbillon or carousel mechanism for a timepiece in which the aforementioned defects are at least partially overcome. Disclosure of the invention

[0005] More specifically, the invention relates to a tourbillon or carousel mechanism for a watch movement, as defined by claim 1. This mechanism comprises:

[0006] - a rotating cage arranged to be set in rotation by a driving source;

[0007] - a balance-spring oscillator carried by said rotating cage;

[0008] - an escapement carried by said rotating cage and arranged to cooperate with said oscillator in order to maintain it in oscillation, said escapement comprising an escape wheel mounted pivotally in or on said cage and rotationally fixed to an escape pinion which meshes with teeth carried by a frame, these teeth being fixed relative to said frame (tourbillon construction) or alternatively capable of being animated by a rotation (carousel construction).

[0009] According to the invention, the tourbillon or carousel mechanism further comprises a fractional time indicator, such as a hand, disc, segment, or similar device, which is kinematically connected to the escape wheel and thus driven by it via a suitable kinematic chain. In other words, the fractional time indicator is kinematically downstream of the escape wheel. The time division may be seconds (in which case the fractional time indicator is a fractional seconds indicator), but other time divisions such as minutes or hours are also possible.

[0010] By these means, a display of fractions of a division of time is obtained, in which the rotation of the escape wheel causes said display instead of that of the cage, which allows an improvement of the display, in particular with regard to the angle traversed by the organ during each step of the escape wheel.

[0011] Advantageously, a drive wheel is provided, fixed in rotation to said escape wheel and arranged to drive said fractional division indicator.

[0012] In one variant, the said fractional division indicator is pivotally mounted on a frame element provided for this purpose, its pivot axis typically being coaxial with that of the cage, but this is not mandatory.

[0013] In an alternative variant, the fractional indicator for a time division is pivotally mounted on the rotating cage. This arrangement is particularly advantageous when the cage is mounted flying method, i.e. supported exclusively on the bottom side, but conventional pivoting between bearings is also possible.

[0014] Advantageously, the said organ for indicating fractions of a division of time is superimposed on a dial carried by the said rotating cage, which makes the indication particularly clear.

[0015] In one variant, the said dial is rotationally fixed to the said rotating cage and consequently pivots with the latter.

[0016] In an alternative version, the dial is pivotally mounted on the rotating cage and is arranged to maintain a constant orientation relative to a fixed, non-rotating component. This dial is therefore of the "orbital dial" type, where the origin of its scale or markings remains the same relative to the 12-6 o'clock axis of the timepiece in which the tourbillon or carousel mechanism is integrated. It should be noted that the main dial of the timepiece can be oriented along the 12-6 o'clock axis, but also in any other desired orientation.

[0017] Advantageously, said constant orientation is ensured by means of a gear carried by said rotating cage and driven from a pinion which is driven by a drive wheel which is rotationally fixed to said escape wheel, said pinion being in kinematic connection with a wheel rotationally fixed to said dial.

[0018] Alternatively, said constant orientation can be ensured by means of a fixed toothing carried by a frame element which is in kinematic connection with a wheel fixed in rotation to said dial.

[0019] Advantageously, the kinematic link between said escape wheel and said fractional division indicator is formed by a chain of gears comprising moving parts all having teeth with a module of less than 0.05mm, but it goes without saying that any suitable module can alternatively be used. Brief description of the drawings

[0020] Further details of the invention will become clearer upon reading the following description, made with reference to the attached drawings in which: - Figure 1 is a schematic isometric view of an embodiment of a vortex or carousel mechanism according to the invention; - Figure 2 is a side cross-sectional view of the tourbillon or carousel mechanism of Figure 1; - Figure 3 is a schematic isometric view of another embodiment of a vortex or carousel mechanism according to the invention; - Figure 4 is a side cross-sectional view of the tourbillon or carousel mechanism of figure 3; - Figure 5 is a schematic isometric view of yet another embodiment of a vortex or carousel mechanism according to the invention; and - Figure 6 is a schematic isometric view of yet another embodiment of a vortex or carousel mechanism according to the invention. Embodiments of the invention

[0021] Figures 1 and 2 illustrate a first embodiment of a tourbillon or carousel mechanism according to the invention. The terms "tourbillon" and "carousel" are to be understood in their broadest sense, encompassing multi-axis, flying, pivoted, etc. tourbillons and carousels. The main difference between a tourbillon and a carousel lies in their drive: in a true tourbillon, the escapement pinion meshes directly or indirectly with fixed teeth, whereas in a carousel there are no fixed teeth, the escapement wheel cooperating with a moving wheel. For the sake of clarity, only the term "tourbillon" is used in the remainder of this description, but it is understood that this corresponds to "tourbillon or carousel" depending on whether the escapement wheel cooperates with fixed or rotating teeth.

[0022] The tourbillon mechanism 1 is equipped with a rotating cage 3, arranged to be pivotally mounted on a frame element (not shown) and rotated by means of a drive source M of any known type (typically a barrel housing a mainspring), which cooperates with cage teeth 5 via a suitable gear train. In the illustrated embodiment, the cage teeth 5 are a pinion located on the bottom side of the cage 3, but other tooth configurations are possible, such as peripheral teeth (internal or external). The cage 3 is pivoted in a free-floating manner, but conventional pivoting between bearings is also possible. Alternatively, the cage 3 can be formed from a board.

[0023] As is generally known, cage 3 houses a balance-spring oscillator 7, here pivoted within cage 3, but either or both of its pivots can be positioned on a frame element alternatively. Although a conventional balance-spring oscillator 7 is shown here, any type of balance wheel and hairspring can be used. Furthermore, the balance-spring 7 is shown as having an axis of rotation coaxial with that of cage 3, but this can alternatively be off-center and thus not coincide with the axis of rotation of cage 3. Moreover, the angle formed by the axis of the display organ 23 and that of cage 3 are parallel in this case, but they could also be non-parallel, in the case where one (or both) of the two is inclined with respect to the vertical (i.e., with respect to a direction perpendicular to the plane of the movement).

[0024] The cage also houses an escapement 9, comprising an escape wheel 11 and a pallet fork 13, which cooperate with each other and with the balance wheel and hairspring in a known manner to maintain the latter's oscillations. The escapement 9 is of the Swiss lever type in the illustrated embodiment, but can take any known form (detent, Omega-Daniels, etc.).

[0025] The escape wheel 11 is rotationally fixed to an escape pinion 15, in order to form an escapement mechanism. Said pinion 15 meshes directly with a toothed gear 17 mounted on a frame element (not shown) in order to rotate the escapement wheel around its axis of rotation when the cage 3 pivots. In the illustrated embodiment, the teeth 17 are fixed relative to the frame (tourbillon construction), but can alternatively be arranged to be driven by a rotation (carousel construction) by means of a drive teeth not shown.

[0026] The rotation speed of cage 3 can be chosen at will, but is typically at one revolution per minute, in order to be able to indicate the seconds by means of an index 19.

[0027] According to the invention, the escape wheel also carries a drive wheel 21, which is also rotationally fixed to the escape wheel 11 and the escape pinion 15.

[0028] This drive wheel rotates a fractional time division indicator 23, pivotally mounted on the cage 3. In the illustrated embodiment, said time division is seconds, and consequently the fractional time division indicator 23 is a fractional second indicator 23 (i.e., one that indicates fractions of a second). This specific terminology is used in the detailed description to simplify the reading in connection with the illustrated embodiments. However, fractions of other time divisions (such as minutes, hours, or others, indicating fractions of a minute, an hour, or other) can be displayed via the fractional time division indicator 23, the gear ratios being, of course, adapted accordingly.This adaptation is within the capabilities of a person skilled in the art and therefore does not need to be described in detail.

[0029] Returning to the embodiment shown in Figure 1, a transmission unit 25, also pivotally mounted on the cage 3, transmits the rotation from the drive wheel 21 to the fraction-second indicator 23, which here takes the form of a needle, but could alternatively be a disk, a segment, or any other suitable shape. This fraction-second indicator 23... moves in front of markings, indexes or similar 29 carried by cage 3, but this is not mandatory.

[0030] The gear ratio between the drive wheel 21 and the fraction-second display element 23 can be selected at will to impart a desired rotational speed to the latter around its axis of rotation. The position of the rotational axis of the fraction-second display element 23 can also be selected at will, either offset from the cage 3 as illustrated in Figures 1 and 2, or coaxial with it. Alternatively, the fraction-second display element 23 can simply be fixed in rotation to the escape wheel 21.

[0031] Advantageously, the drive wheel 21, the toothed members of the transmission unit 25 and the wheel 27 which is rotationally fixed to the fraction-second indicator member 23 can all have a tooth module of less than 0.05 mm, which allows for a smoother and less jerky drive.

[0032] During the operation of the tourbillon mechanism 1 according to the invention, the fraction-second indicator organ 23 pivots around its own axis of rotation relative to the cage 3, under the drive of the escapement mobile 11, 15 and according to the rotations of the latter.

[0033] Figures 3 and 4 illustrate a second embodiment of a tourbillon mechanism 1 according to the invention, which differs from that of Figures 1 and 2 in that the fraction-seconds indicator 23 is not carried by the cage 3, but by a support 31 which is rotationally fixed to the frame and / or the dial, the axis of rotation of the fraction-seconds indicator 23 being coaxial with that of the cage 3.

[0034] Figure 5 further illustrates an embodiment of a tourbillon mechanism 1 according to the invention, which differs from that of Figures 1 and 2 in that the markings or indices 29 are carried by an orbital dial 33, off-center with respect to the axis of rotation of the cage 3 and arranged to pivot around its own axis of rotation so as to maintain the same orientation with respect to the frame and / or the main dial of the timepiece in which said tourbillon mechanism is integrated.

[0035] For this purpose, the orbital dial 33 is mounted for rotation on the cage 3 and is rotationally fixed to a wheel 35, which is driven in rotation by means of a pinion 37. This pinion is rotationally fixed to the transmission unit 25 by means of a gearbox 39, also pivotally mounted on the cage by means of an axle and pivots (not shown). It should also be noted that the pinion 37, the gearbox 39, and the wheel 35 have been represented by their pitch circles; their teeth have not been drawn.

[0036] The gear ratio between said pinion 37 and said wheel 35 is chosen so that said orbital dial 33 completes a revolution around its own axis of rotation in the same period, but in the opposite direction to said cage 3 to keep its orientation relative to the frame and / or the main dial.

[0037] Figure 6 further illustrates an embodiment of a tourbillon mechanism according to the invention, also with an orbital dial 33. This embodiment differs from that of Figure 5 with regard to the drive of the pivoting of the orbital dial 33 around its own axis of rotation.

[0038] In this variant, a pair of linkages kinematically connect the wheel 39 to a fixed gear 45 mounted rotationally to a frame element (not shown). Again, the elements 39, 41, 43, and 45 have been represented by their pitch circles, and the axes of the linkages 41 and 43 have not been shown.

[0039] The gear ratio between the fixed teeth and the wheel 39 is chosen so that said orbital dial 33 makes a revolution around its own axis of rotation in the same period, but in the opposite direction to said cage 3 to keep its orientation relative to the frame and / or the main dial.

[0040] Regarding usable materials, the entire range of materials used in contemporary watchmaking can be considered (metals, non-metals such as silicon, silicon compounds, synthetic diamond, sapphire, structureable glasses, ceramics, glass-ceramics, metallic glasses, polymers, composites, materials suitable for additive manufacturing, etc.). Furthermore, flexible pivots can be used for components where this makes technical sense.

[0041] Although the invention has been described in connection with particular embodiments, other variants are possible without departing from the scope of the invention as defined by the attached claims.

Claims

Claims 1. Tourbillon (1) or carousel mechanism for a watch movement, comprising: - a rotating cage (3) arranged to be rotated by a driving source (M); - a balance-spring oscillator (7) carried by said rotating cage (3); - an escapement (9) carried by said rotating cage (3) and arranged to cooperate with said oscillator (7) in order to maintain its oscillation, said escapement (9) comprising an escape wheel (11) pivotally mounted relative to said rotating cage (3) and integral in rotation with an escape pinion (15) which meshes with a toothing (17) carried by a frame element; characterized in that said tourbillon (1) or carousel mechanism comprises a member for indicating the fractions of a time division (23) in kinematic connection with said escape wheel (11).

2. Tourbillon mechanism (1) or carousel according to the preceding claim, comprising a drive wheel (21) integral in rotation with said escape wheel (11) and arranged to drive said member for indicating the fractions of a time division (23).

3. Tourbillon mechanism (1) or carousel according to one of the preceding claims, in which said member for indicating the fractions of a time division (23) is pivotally mounted on a frame element (31).

4. Tourbillon mechanism (1) or carousel according to one of claims 1 and 2, in which said member for indicating the fractions of a time division (23) is pivotally mounted on said cage (3).

5. Tourbillon mechanism (1) or carousel according to claim 4, in which said member for indicating the fractions of a time division (23) is superimposed on a dial (33) carried by said cage (3).

6. Tourbillon mechanism (1) or carousel according to claim 5, in which said dial (33) is integral in rotation with said cage (3).

7. Tourbillon (1) or carousel mechanism according to claim 5, wherein said dial (33) is pivotally mounted on said cage (3) and is arranged so as to have a constant orientation relative to a frame element.

8. Tourbillon mechanism (1) or carousel according to the preceding claim, in which said constant orientation is ensured by means of a gear train (35, 37, 39) carried by said cage and driven from a pinion (37) which is driven by a drive wheel (21) which is rotationally fixed to said escape wheel (11), said pinion (37) being kinematically connected to a wheel (35) rotationally fixed to said dial (33).

9. Tourbillon mechanism (1) or carousel according to claim 7, in which said constant orientation is ensured by means of fixed teeth (45) carried by a frame element and which is kinematically connected to a wheel (39) integral in rotation with said dial (33).

10. Tourbillon mechanism (1) or carousel according to one of the preceding claims, in which the kinematic connection (21, 25, 27) between said escape wheel (11) and said member for indicating the fractions of a time division (23) is formed of a chain of gears comprising mobiles (21, 25, 27) all having teeth having a module of less than 0.05 mm.

11. Tourbillon (1) or carousel mechanism according to one of the preceding claims, wherein said time division is seconds.

12. Clockwork movement comprising a tourbillon (1) or carousel mechanism according to one of the preceding claims.

13. Timepiece comprising a timepiece movement according to the preceding claim.

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