CH714617A2 - Movement and timepiece. - Google Patents

Abstract

The object of the present invention is to provide a movement and a timepiece of reduced thickness while ensuring the power reserve level of the mainspring barrel. Such a movement comprises: a large mobile (42) which is rotatably mounted at the front of a plate (21) and to which the rotational force of a movement cylinder (41) is transmitted; a third mobile which is rotatably mounted at the front of the plate (21) and to which the rotational force of the large mobile (42) is transmitted; a rear wheel (33) rotatably mounted at the rear of the plate (21); and a central transmission wheel (45) which connects the rear wheel (33) and the large wheel (42) and transmits the rotational force of the large wheel (42) to the rear wheel (33).

Description

Description

BACKGROUND OF THE INVENTION

1. Field of the invention The present invention relates to a movement and a timepiece.

2. Description of the Prior Art In the movement of a timepiece, a movement barrel is rotated by the return force of a mainspring housed in the movement barrel, thanks to whereby a rotational force is transmitted to the various gear trains. For example, patent document 1 (JP-A-2004-170,271) discloses a structure in which a large mobile and a third mobile are successively connected to the movement barrel.

In patent document 1, a third pinion of the third mobile meshes with a large wheel of the large mobile and a driving mobile. On the other hand, a third wheel of the third mobile meshes with a second gear of a second mobile.

In this structure, the third mobile is rotated by the rotational force of the large mobile, the second mobile performing a rotation every 60 seconds, and the training mobile performing a rotation every 60 minutes.

Conventional movements, however, leave room for improvement in terms of achieving a reduction in the thickness of the movement while ensuring the power reserve associated with the barrel spring (i.e. - say the period of time elapsing from its reassembled state, where it is wound on itself, until it regains its nominal length at rest). In other words, in conventional movements, the third mobile is kinematically directly connected to the large mobile and to the training mobile, so that there are restrictions as to the arrangement of the third mobile. Thus, in the case, for example, where the third mobile and the movement barrel are arranged to be superimposed on each other in a plan view taken in the axial direction, it is necessary, for example, to render the thickness of the movement barrel much smaller.

SUMMARY OF THE INVENTION An object of the present application is to propose a movement and a timepiece in which a reduction in thickness is achieved, while ensuring the power reserve of the main barrel spring.

In order to achieve the above goal, there is provided, according to one embodiment of the present application, a movement comprising: a large mobile which is rotatably mounted in front of a plate and to which a force of rotation of a movement barrel is transmitted; a third mobile which is rotatably mounted at the front of the plate and to which a rotational force of the large mobile is transmitted; a rear train rotatably mounted at the rear of the plate; and a central transmission wheel which makes the connection between the rear gear and the large mobile, and which transmits the rotational force of the large mobile to the rear gear.

According to this present embodiment, the rear train is kinematically connected to the large mobile via the central transmission wheel, so that, compared to a conventional structure in which the third mobile is kinematically connected to the large mobile and to the train rear (for example, the driving mobile), it is possible to achieve an improvement in terms of degree of freedom for the arrangement of the third mobile. Thus it is possible to move the third mobile far from the movement barrel, and it is possible, for example, to make an arrangement according to which the third mobile and the movement barrel are not superimposed one on the other according to a plan view. Therefore, it is possible to guarantee the thickness of the movement barrel while achieving a reduction in thickness of the movement. By guaranteeing the thickness of the movement barrel, it is possible to accommodate a large mainspring in the movement barrel, so that it is possible to ensure the duration of the power reserve of the main barrel spring.

In the above movement, the central transmission wheel can be arranged at the front of the plate, and the central transmission wheel and the rear train can be connected to each other via an opening of communication formed in the circuit board.

In the presently described embodiment, it is possible to mount the central transmission wheel to the plate during the assembly process of the front side of the plate, thus making it possible to kinematically easily connect the large mobile to the wheel. transmission center.

In the above movement, the central transmission wheel can be engaged with a driving mobile constituting the rear train.

According to the present embodiment, the rotational force of the large mobile is transmitted to the driving mobile via the central transmission wheel, so that, for example compared to the case where the central transmission wheel is kinematically connected to an hour wheel, it is possible to reduce the transmission ratio between the central wheel

CH 714 617 A2 transmission and rear wheel drive. Consequently, the transmission of the rotational force from the large mobile to the rear wheel train can be carried out smoothly.

In the movement of the above mode, the third mobile can be located so as not to overlap the movement barrel in a plan view taken in the direction of the thickness of the plate.

In this embodiment, it is possible to guarantee the thickness of the movement barrel while eliminating any interference between the third mobile and the movement barrel. Consequently, it is possible to achieve a reduction in the thickness of the movement while ensuring the duration of the power reserve of the main barrel spring.

In the above movement, one can provide a second mobile which is rotatably mounted at the front of the plate and to which the rotational force of the third mobile is transmitted, an exhaust-regulator which has a mobile exhaust that can be removably engaged with an anchor and that controls the rotation of the movement barrel, and an intermediate exhaust mobile acting as a link between the exhaust mobile and the second mobile.

According to the present embodiment, the external diameter of the second mobile (seconds wheel) itself can be reduced, so that it is possible to remove the overlap or overlap according to a plan view of the second mobile screw -in relation to a peripheral element (for example, a röchet). Therefore, it is possible to achieve an additional thickness reduction for the movement. In addition, it is possible to reduce the external diameter of the second mobile, so that there is no need to excessively reduce the dimensions of the module (diameter of the inner pitch circle / number of teeth) of the second mobile in order to guarantee the acceleration ratio of the second mobile relative to the exhaust mobile. Consequently, it is possible to efficiently transmit the rotational force from the second mobile to the exhaust mobile.

Furthermore, the external diameter of the second mobile is reduced, whereby it is also possible to improve the possibilities of arrangement of the third mobile.

In the movement of the above embodiment, the number of teeth of the third wheel meshing with the big wheel, and the number of teeth of the central transmission wheel meshing with the big wheel can be less than the number of ferris wheel teeth.

According to this mode, the speed of rotation in revolutions per minute (often indicated by the acronym RPM, for "rounds per minute") of the third mobile and that of the central transmission wheel are increased compared to that of large mobile, so that the number of teeth of the large mobile can be easily adjusted. Therefore, unlike the conventional case, where the third mobile is used to both accelerate the large mobile and brake the training mobile, it is possible to achieve an improvement in terms of the transmission efficiency of the rotational force.

A timepiece according to a mode of the present patent application can be equipped with a movement of the above mode.

According to this embodiment, it is possible to propose a fine timepiece, but whose power reserve is important (long life of the barrel spring).

According to a mode of the present application, it is possible to propose a fine movement and a timepiece ensuring the power reserve of the mainspring.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an external view of a timepiece.

Fig. 2 is a plan view of a movement seen from the front side.

Fig. 3 is a plan view of the movement seen from the rear side.

Fig. 4 is a sectional view along the axis IV — IV of FIG. 2.

Fig. 5 is a sectional view along the axis V-V of FIG. 2.

Fig. 6 is a sectional view along the axis VI-VI of FIG. 2.

Description of preferred embodiments In the following, an embodiment of the present invention will be described with reference to the drawings.

[Timepiece] [0026] FIG. 1 is an external view of a timepiece 1. In the drawings which follow, certain timepiece components are omitted and each timepiece component is shown in a simplified manner in order to facilitate understanding of the drawings.

CH 714 617 A2 As can be seen in fig. 1, in the timepiece 1 according to the present embodiment, a movement 2, a dial 3, indicator hands 4 to 6, etc. are incorporated into a timepiece case 7.

The case 7 of the timepiece is equipped with a case middle 11, a case back (not shown), and a protective glass 12 (the glass). A crown 15 is provided at a lateral surface of the middle part 11 of the case corresponding to the position at 3 o'clock (see the right side in fig. 1). The crown 15 is used to operate the movement 2 from the outside of the middle part 11 of the case. The crown 15 is fixed to a winding stem 19 inserted in the middle part 11 of the case.

[Movement] [0030] In movement 2, several wheels etc. are rotatably mounted on a plate 21 constituting the base plate of the movement 2. The winding stem 19 mentioned above is inserted in the plate 21. The winding stem 19 is used during the date and time correction. The winding stem 19 is rotatable about its axis, and can be moved in the axial direction. In the following description, reference is made to the side of the protective glass or crystal 12 (the side of the dial 3) of the case 7 of the timepiece relative to the plate 21 as being the "rear side" of the movement 2 , and on the rear side of the case (the side opposite to that of the dial 3) as being the “front side” of movement 2. Each toothed wheel described below is arranged so that its axial direction is the front-rear direction of movement 2.

[0031] FIG. 2 is a plan view of movement 2 seen from the front side. Fig. 3 is a bottom view of movement 2 seen from the rear side.

Movement 2 mainly has a front gear train 31 and an exhaust-regulator 32 arranged in front of the plate 21, as illustrated in FIG. 2, and a rear train 33 arranged at the rear of the plate 21, as can be seen in FIG. 3.

[Front gear train] [0034] FIG. 4 is a sectional view along the axis IV — IV of FIG. 2.

As illustrated in FIG. 4, the front gear train 31 is mainly equipped with a movement barrel 41, a large mobile 42, a third mobile 43, a second mobile 44 constituting the second mobile, and a central transmission wheel 45 (see fig. 6). The front gear train 31 constitutes an acceleration train in which the rotation speed in revolutions per minute (RPM for "rounds per minute") of a wheel is all the higher as the steps of transmission.

The movement barrel 41 is rotatably mounted between the plate 21 and a barrel bridge 51. The movement barrel 41 contains a motor spring, also called main spring (not shown) serving as an energy source for the workpiece d 'horlogerie 1. The mainspring is wound via a röchet 46, for example, by turning the winding stem 19. The movement barrel 41 is rotated by the rotational force (return force of the spring wound on itself ) when the mainspring is in its wound state. In timepiece 1 of this embodiment, the mainspring can also be wound up under the action of the rotation of an oscillating mass 40 following the movements of the user. Movement 2, however, can be made up of a structure with no oscillating mass 40.

The large mobile 42 is rotatably mounted between the plate 21 and the gear train 52. The axis of the large mobile 42 is arranged so as not to overlap the movement barrel 41 according to a plan view taken in the direction before behind. A center pinion 42a of the large mobile 42 meshes with a barrel wheel 41 a of the movement barrel 41. Consequently, the large mobile 42 is driven in rotation by the rotational force transmitted from the movement barrel 41.

The third mobile 43 is rotatably mounted between the plate 21 and the gear train 52. The axis of the third mobile 43 is arranged so as not to overlap the movement barrel 41 and the large mobile 42 according to a view in plan. A third pinion 43a of the third mobile 43 meshes with a large wheel 42b of the large mobile 42. According to the present embodiment, the number of teeth of the third pinion 43a is less than the number of teeth of the large wheel 42b.

A third wheel 43b of the third mobile 43 is arranged so as not to overlap the movement barrel 41 according to a plan view. More specifically, the third wheel 43b is arranged in height in a space comprising the thickness of the movement barrel 41 (that is to say of the barrel drum 41b) in the front-rear direction. The third wheel 43b, however, can be arranged so as to be offset with respect to the barrel drum 41b in the front-rear direction.

The second mobile 44 is rotatably mounted between the plate 21 and the gear train 52. The second mobile 44 is arranged coaxially with the center of the movement 2. A second pinion 44a of the second mobile 44 meshes with the third wheel 43b. A second shaft 44b of the second mobile 44 is rotatably inserted in a central tube 47 fixed to the plate 21. The central tube 47 extends through the plate 21 in the front-rear direction and projects from the rear side of the plate 21. In the second mobile 44, the rear end of the second shaft 44b projects from the rear side beyond the central tube 47.

[Exhaust-regulator]

CH 714 617 A2 As illustrated in fig. 2, the exhaust-regulator 32 is kinematically connected at the output of the front gear train 31 via an intermediate escape wheel 48. The exhaust-regulator 32 controls the rotation of the movement barrel 41. The exhaust-regulator 32 has an exhaust mobile 61, an anchor 62 and a balance spring 63.

[0043] FIG. 5 is a sectional view along the line V-V of FIG. 2.

As illustrated in FIG. 5, the exhaust mobile 61 is rotatably mounted between the plate 21 and an escape wheel bridge 54. An exhaust pinion 61 a of the exhaust mobile 61 meshes with an intermediate wheel 48a of the escape wheel intermediate 48. The intermediate escape wheel 48 is rotatably mounted between the gear train bridge 52 and the escape wheel bridge 54. An intermediate pinion 48b of the intermediate escape wheel 48 meshes with a seconds wheel 44c of the second mobile 44. The exhaust pinion 61a can mesh directly with the seconds wheel 44c.

As illustrated in FIG. 2, the anchor 62 is rotatably mounted between the plate 21 and an anchor bridge 55, in a front-rear direction corresponding to the front-rear direction of the movement. The anchor 62 is equipped with a pair of pallets 65a and 65b. When the anchor 62 rotates alternately in a reciprocating movement, the pallets 65a and 65b engage alternately with an escape wheel 61b of the exhaust mobile 61. The rotation of the mobile exhaust 61 is temporarily stopped when one of the pallets of the pair of pallets 65a and 65b is engaged with the escape wheel 61b. The exhaust mobile 61 rotates when the pair of paddles 65a and 65b is released from the exhaust wheel 61b. These operations are repeated continuously, and by means of these, the exhaust mobile 61 rotates intermittently.

The balance spring 63 regulates the exhaust mobile 61 (that is to say encourages the mobile exhaust 61 to rotate at a fixed speed). More specifically, the balance spring 63 is rotatably mounted between the plate 21 and a balance bridge 56, its axial direction corresponding to the front-rear direction of the movement. More specifically, the balance spring 63 is rotated in a reciprocating movement at a fixed frequency thanks to the energy transmitted by a spiral spring 67 (see fig. 5). The spiral balance 63 engages with a fork 62a of the anchor 62, and is disengaged from it repeatedly (see fig. 5) in synchronization with the alternating rotational movement. Consequently, via the alternating rotation of the anchor 62, the pallets 65a and 65b come to engage with the exhaust mobile 61 and repeatedly disengage therefrom.

[Rear wheel drive] [0048] FIG. 6 is a sectional view along the axis VI-VI of FIG. 2.

As illustrated in FIGS. 3 and 6, the rear wheel 33 mainly has a driving mobile 71, a minute mobile 72 (see fig. 3), and an hour wheel 73.

As shown in FIG. 6, behind the plate 21, the driving mobile 71 is rotatably inserted in the central tube 47 mentioned above. The driving mobile 71 is kinematically connected to the front gear train 31 via the central transmission wheel 45.

As illustrated in FIG. 3, the minutes mobile 72 is rotatably mounted on the plate 21. A minute wheel 72a of the minutes mobile 72 meshes with a pinion driving 71 a of the driving mobile 71.

As shown in FIG. 5, the hour wheel 73 is inserted into the driving mobile 71. The hour wheel 73 can rotate between the plate 21 and an hour wheel support 58 relative to the driving mobile 71. A minute pinion 72b (see fig. 3) of the minute wheel 72 meshes with the hour wheel 73.

According to this embodiment, the number of teeth of the second mobile 44 (the second mobile) mentioned above is adjusted so that it rotates every 60 seconds. In the second mobile 44, the second hand 6 is mounted on the rear end of the second shaft 44b.

The number of teeth of the driving mobile 71 is adjusted so that it rotates every 60 minutes. The minute hand 5 is mounted on the part of the driving mobile 71 projecting from the rear of the movement, beyond the hour wheel support 58.

The number of teeth on the hour wheel 73 is adjusted so that it rotates in 12 hours. The hour hand 4 is mounted on the part of the hour wheel 73 projecting from the rear of the movement beyond the hour wheel holder 58.

Here, as illustrated in FIG. 6, the central transmission wheel 45 mentioned above makes the connection between the large mobile 42 and the driving mobile 71, that is to say ensures the kinematic connection between these two mobile. The central transmission wheel 45 is rotatably mounted on the part of the plate 21 located behind the barrel 41 of the movement. According to the plan view of FIG. 6, the entire central transmission wheel 45 overlaps the movement barrel 41. The central transmission wheel 45, however, can be arranged so as to only partially overlap the movement barrel 41 according to a plan view, or it can be arranged so as not to overlap at all the barrel 41 of the movement according to a plan view.

CH 714 617 A2 According to the present embodiment, the central transmission wheel 45 is located at the rear of the third wheel 43b. A transmission wheel 45a of the central transmission wheel 45 meshes with the large wheel 42b. In other words, the rotational force of the large mobile 42 is transmitted to the central transmission wheel 45 and to the third mobile 43 via the large wheel 42b.

At the part of the plate 21 adjacent to the central transmission wheel 45, a communication opening 21 a is formed, establishing communication between the front and the rear of the plate 21. A driving wheel 71 b of the driving mobile 71 and a transmission pinion 45b of the central transmission wheel 45 faces the communication opening 21a. The driving wheel 71b and the transmission pinion 45b mesh with each other through the communication opening 21a. While in the embodiment described above the large mobile 42 and the driving mobile 71 are connected to each other by a central transmission wheel 45, this should not be interpreted in a restrictive manner. For example, the large mobile 42 and the training mobile 71 could be kinematically connected by means of a plurality of center transmission wheels.

[Operation of the timepiece] In what follows, we will describe the operation of the timepiece 1 described above.

In timepiece 1 of this embodiment, when the movement barrel 41 is driven by the restoring force of the mainspring, the large mobile 42, the third mobile 43, and the second mobile 44 are driven in rotation while being controlled by the exhaust-regulator 32.

The rotational force of the large mobile 42 is transmitted to the central transmission wheel 45 in addition to the third mobile 43. Consequently, the central transmission wheel 45 rotates, and, thanks to the latter, the driving mobile. 71 also turns. The rotational force of the driving mobile 71 is transmitted to the hour wheel 73 via the minute mobile 72, which in turn turns the hour wheel 73.

As a result, the timepiece 1 shows the passing of time.

Thus, according to the present proposed embodiment, there is provided a central transmission wheel 45 kinematically connecting the large mobile 42 to the rear train 33 (formed by the driving mobile 71).

In such a configuration, the rear train 33 is kinematically connected to the large mobile 42 via the central transmission wheel 45, so that in comparison with a conventional structure, in which the third mobile is kinematically connected to the large mobile and at the driving mobile, it is possible to achieve an improvement in terms of degree of freedom for the arrangement of the third mobile 43. Consequently, it is possible to move the third mobile 43 away from the movement barrel 41, making it possible, for example, an arrangement of the third mobile 43 and of the movement barrel 41 so that they do not overlap each other in a plan view. Therefore, it is possible to guarantee the thickness of the barrel 41 of the movement while achieving a reduction in thickness of the movement 2. By guaranteeing the thickness of the movement barrel 41, it is possible to accommodate a large driving spring in the barrel 41 of the movement, so that it is possible to ensure the power reserve, that is to say the life of the mainspring.

According to this embodiment, the central transmission wheel 45 is arranged at the front of the plate 21, and the central transmission wheel 45 and the driving mobile 71 are connected to each other via the communication opening 21a of the plate 21.

In such a structure, it is possible to mount the central transmission wheel 45 to the plate 21 during the assembly process of the front of the plate 21, and the kinematic connection of the large mobile 42 to the central wheel 45 transmission is facilitated.

According to this embodiment, the central transmission wheel 45 is kinematically connected to the driving mobile 71 of the rear wheel 33.

In such a structure, the rotational force of the large mobile 42 is transmitted to the driving mobile 71 via the central transmission wheel 45, so that compared, for example, in the case where the central transmission wheel 45 is connected to the hour wheel 73, it is possible to reduce the transmission ratio between the central transmission wheel 45 and the rear wheel train 33. Consequently, it is possible to transmit the rotation force of the train more smoothly gear 31 front to rear gear 33.

In this embodiment, the third mobile 43 is arranged so as not to overlap the movement barrel 41 in a plan view.

In such a configuration, it is possible to guarantee the thickness of the movement barrel 41 while eliminating the interference between the third mobile 43 (the third wheel 43b) and the movement barrel 41. Consequently, it is possible to reduce the thickness of movement 2 while ensuring the power reserve duration of the main spring of the barrel.

According to this embodiment, the second mobile 44 and the exhaust mobile 61 are kinematically connected to each other via the intermediate escapement wheel 48.

CH 714 617 A2 In such a configuration, it is possible to reduce the external diameter of the seconds mobile 44 (the seconds wheel 44c), so that it is possible to remove any overlap between the seconds wheel 44c and a peripheral element (for example, röchet 46) in a plan view. This helps to achieve an additional thickness reduction for movement 2. Furthermore, it is possible to reduce the external diameter of the seconds wheel 44c, so that there is no need to reduce the dimensions excessively. of the module (diameter of the pitch circle / number of teeth) of the second wheel 44c in order to guarantee the acceleration ratio of the second wheel 44c relative to the exhaust mobile 61 (the exhaust pinion 61 a). Consequently, it is possible to efficiently transmit the rotational force of the second mobile 44 to the exhaust mobile 61.

In addition, the external diameter of the seconds wheel 44c is reduced, so that it is possible to achieve an improvement in terms of flexibility for the arrangement of the third mobile 43.

In the present embodiment, the number of teeth of the third mobile 43 (the third wheel 43b) and the number of teeth of the central transmission wheel 45 (the transmission wheel 45a) are less than the number of teeth of the large mobile 42 (the big wheel 42b).

In such a configuration, the number of revolutions per minute (rpm, acronym for "rounds per minute") of the third mobile 43 and that of the central transmission wheel 45 is increased compared to that of the large mobile 42, so that the number of teeth of the big wheel 42b can be easily defined. Consequently, unlike the conventional case where the third mobile (the third pinion) is used both for the acceleration of the large mobile (the big wheel) and the braking of the driving mobile, it is possible to achieve an improvement in terms of transmission efficiency of the rotational driving force.

The timepiece 1 of this embodiment is equipped with the movement 2 described above, so that it is possible to propose a timepiece 1 which is thin, and which also has a long-lasting power reserve.

[Other possible variants] The preferred embodiment of the present invention described above should not be interpreted in a restrictive manner. It is possible to add, delete, replace, and still make other modifications to components without departing from the scope and spirit of the present invention. The present invention is not limited to the above description but is limited only to the appended claims.

For example, while according to the embodiment described above the large mobile 42 and the driving mobile 71 are kinematically connected to each other via the central transmission wheel 45, this should not be interpreted restrictively. For example, the central transmission wheel 45 can be connected to any wheel (for example, the hour wheel 73) constituting the rear gear 33.

While in the embodiment described above the central transmission wheel 45 is arranged in front of the plate 21, this should not be interpreted restrictively either. The central transmission wheel 45 can be arranged at the rear of the plate 21.

While in the embodiment described above the central transmission wheel 45 increases the number of revolutions per minute of the large mobile 42 and transmits this speed of rotation to the rear train 33, this should not be interpreted in such a way restrictive. The central transmission wheel 45 could also reduce the number of revolutions per minute of the large mobile 42.

Apart from these modifications, the components of the embodiment described above can be replaced by known components without departing from the scope of the spirit of the present invention. In addition, the modifications and variations described above can be appropriately combined as required.

Description of reference numbers and signs [0084] timepiece with platinum movement

21a communication opening exhaust-regulator rear wheel movement barrel

CH 714 617 A2 large mobile third mobile second mobile central transmission wheel mobile mobile exhaust drive

Claims (7)

claims 1. Movement (2) comprising: a large mobile (42) which is rotatably mounted at the front of a plate (21) and to which a rotational force of a movement barrel (41) is transmitted; a third mobile (43) which is rotatably mounted at the front of the plate (21) and to which a rotational force of the large mobile (42) is transmitted; a rear train (33) rotatably mounted at the rear of the plate (21); and a central transmission wheel (45) which makes the connection between the rear train (33) and the large mobile (42), and which transmits the rotational force of the large mobile (42) to the rear train (33). 2. Movement (2) according to claim 1, in which the central transmission wheel (45) is arranged at the front of the plate (21), and the central transmission wheel (45) and the rear train (33) are connected to each other via a communication opening (21a) formed in the plate (21). 3. Movement according to one of claims 1 or 2, wherein the central transmission wheel (45) meshes with a driving mobile (71) constituting the rear train. 4. Movement according to one of claims 1 to 3, wherein the third mobile (43) is arranged so as not to overlap the movement barrel (21) in a plan view taken in the direction of the thickness of the plate . 5. Movement according to one of claims 1 to 4, in which are arranged: a seconds mobile (44) which is rotatably mounted at the front of the plate (21) and to which the rotational force of the third mobile (43) is transmitted, an exhaust-regulator (32) which has an exhaust mobile (61) capable of engaging in a removable manner with an anchor (62) and which controls the rotation of the movement barrel (41), and an intermediate escapement wheel effecting the connection between the escapement mobile (61) and the seconds hand (44). 6. Movement according to one of claims 1 to 5, wherein the number of teeth of the third wheel (43b) meshing with the large wheel (42b), and the number of teeth of the central transmission wheel (45a) meshing with the big wheel (42b) are less than the number of teeth of the big wheel (42b). 7. Timepiece equipped with a movement according to claim 6.