阅读说明：本技术 用于具有滚轮的钟表显示机构的调节机构 (Adjusting mechanism for a timepiece display mechanism with a roller ) 是由 A·佐格 C·利多 于 2019-06-17 设计创作，主要内容包括：本发明涉及用于钟表显示机构(20)的调节机构(10),该钟表显示机构包括输入轮(2),该输入轮驱动控制第一显示构件(30)的位置的控制轮(3),该调节机构包括差动机构(50),该差动机构包括驱动轮副(4),该驱动轮副由定位杆(40)保持并可经由第一输入轮(2)枢转,以驱动与控制轮(3)啮合并相对于摩擦安装在框架(15)上的行星轮架(6)偏心地枢转的行星轮(5),差动机构(50)在差动机构的一个输入端静止时将另一输入端和输出端之间的旋转乘以特定因数,行星轮架(6)包括操纵装置(7),其允许表技师释放摩擦以改变行星轮(5)的角位置,从而改变控制轮(3)的角位置,以使其相对于另一显示构件(80)正确转位。(The invention relates to an adjustment mechanism (10) for a timepiece display mechanism (20) comprising an input wheel (2) driving a control wheel (3) controlling the position of a first display member (30), the adjustment mechanism comprising a differential mechanism (50) comprising a drive wheel set (4) held by a positioning lever (40) and pivotable via the first input wheel (2) to drive a planet wheel (5) engaged with the control wheel (3) and pivoted eccentrically with respect to a planet wheel carrier (6) frictionally mounted on a frame (15), the differential mechanism (50) multiplying the rotation between one input and the output of the differential mechanism by a specific factor when the other input is stationary, the planet wheel carrier (6) comprising an operating device (7) allowing a timepiece technician to release the friction to change the angular position of the planet wheel (5), thereby changing the angular position of the control wheel (3) to correctly index it with respect to the other display member (80).)

1. An adjustment mechanism (10) for a timepiece display mechanism (20), the timepiece display mechanism (20) including at least a first input wheel (2), the first input wheel (2) being arranged to directly or indirectly drive a first control wheel (3), the first control wheel (3) being used to control the position of a first display member (30) included in the timepiece display mechanism (20), characterized in that the adjustment mechanism (10) includes a differential gear train mechanism (50), the differential gear train mechanism (50) including a drive wheel set (4), the drive wheel set (4) of the differential gear train mechanism (50) being held by a display positioning lever (40) and arranged to be pivoted by the first input wheel (2), and the drive wheel set (4) being arranged to drive at least one planet wheel (5), the planet wheel (5) being in mesh with the first control wheel (3) and being pivotally and eccentrically mounted with respect to a planet wheel carrier (6), the planet wheel carrier (6) is friction-mounted in a cavity (62) of a frame (15) of the regulating mechanism (10) or on a shoulder of the frame (15) by means of internal friction, the differential gear train mechanism (50) is arranged to multiply the rotation between one input and the output of the differential mechanism by a certain factor when the other input of the differential mechanism is stationary, and the planet wheel carrier (6) comprises an operating device (7), the operating device (7) being arranged to allow a watch technician to release the friction to change the angular position of the planet wheels (5) which determines the position of the first control wheel (3) to correctly index the first control wheel (3) relative to at least one other display member (80) of the timepiece display mechanism (20).

2. A timepiece display mechanism (20), the timepiece display mechanism (20) comprising at least one adjustment mechanism (10) according to claim 1, the timepiece display mechanism (20) being an instantaneous or semi-instantaneous display mechanism, wherein the first input wheel (2) is a large wheel comprising at least 24 teeth, the timepiece display mechanism (20) comprising at least one driving wheel set (9), the driving wheel set (9) of the timepiece display mechanism (20) comprising at least one finger (90), the finger (90) being arranged to directly or indirectly drive the first input wheel (2), the timepiece display mechanism (20) comprising at least one intermediate wheel (91) between each of the driving wheel sets (9) and the first input wheel (2) of the timepiece display mechanism (20), the number of teeth of the intermediate wheel (91) being less than or equal to half the number of teeth of the first input wheel (2), each finger (90) is arranged to cooperate with said intermediate wheel (91) or with a star wheel (92) pivoting integrally with said intermediate wheel (91), said timepiece display mechanism (20) comprising at least one input positioning lever (93) for a locking position engaging only with said intermediate wheel (91) or with said star wheel (92) and a correcting positioning lever (94), this correcting positioning lever (94) also engaging only with said intermediate wheel (91) or with said star wheel (92) for changing said position.

3. The timepiece display mechanism (20) according to claim 2, characterised in that at least one of the intermediate wheels (91) pivots integrally with the star wheel (92).

4. Timepiece display mechanism (20) according to claim 2, characterised in that the timepiece display mechanism (20) comprises one said drive wheel set (9) as a drive wheel set and one said drive wheel set (9) as a correction wheel set.

5. The timepiece display mechanism (20) according to claim 2, characterised in that the intermediate wheel (91) is arranged to move the first input wheel (2) or the second input wheel (22) pivoted synchronously with the first input wheel (2) by only one tooth at each position jump of the at least one intermediate wheel (91).

6. The timepiece display mechanism (20) according to claim 2, characterised in that the pivot axis of at least one of the intermediate wheels (91) is orthogonal to the pivot axis of the first input wheel (2) or to the pivot axis of a second input wheel (22) pivoted synchronously with the first input wheel (2).

7. The timepiece display mechanism (20) according to claim 5, characterised in that the timepiece display mechanism (20) includes the second input wheel (22) or front wheel (21) which pivots synchronously with the first input wheel (2), and in that the second input wheel (22) or front wheel (21) cooperates with at least one of the intermediate wheels (91).

8. Timepiece display mechanism (20) according to claim 2, characterised in that the timepiece display mechanism (20) comprises only one intermediate wheel (91), the intermediate wheel (91) being arranged to cooperate with each drive wheel set (9) of the timepiece display mechanism (20).

9. A timepiece display mechanism (20), the timepiece display mechanism (20) comprising an adjustment mechanism (10) according to claim 1, the timepiece display mechanism (20) being a roller-type display mechanism, wherein the first display member (30) is a first roller and at least one of the other display members (80) is a second roller coaxial with the first roller.

10. The timepiece display mechanism (20) according to claim 9, characterised in that the coaxial second roller is arranged to be driven directly or indirectly by the first input wheel (2) or by a second input wheel (22) pivoted synchronously with the first input wheel (2).

11. The timepiece display mechanism (20) according to claim 10, characterised in that the coaxial second roller is arranged to be driven directly or indirectly by a second input wheel (22) pivoted in synchronism with the first input wheel (2) and having an incomplete toothing.

12. Timepiece display mechanism (20) according to claim 9, characterised in that the roller comprises at least one tab (12) having two faces, the tab (12) having two display symbols on both sides, the tab (12) pivoting integrally with a pinion (13), the pinion (13) being arranged to pivot when meshing with a toothed segment (14) comprised in a frame (15) of the timepiece display mechanism (20).

13. The timepiece display mechanism (20) according to claim 9, characterised in that the timepiece display mechanism (20) is a date display mechanism, the first roller being a ones display roller indirectly driven by the first input wheel (2), the first input wheel (2) being a 31-tooth wheel from which one tooth is removed or from which two consecutive teeth are removed, and the second roller being a tens roller directly driven by a second input wheel (22) pivoted in synchronism with the first input wheel (2), the second input wheel (22) being a truncated 31-tooth wheel retaining only 4 teeth in the positions of 10, 20, 30 and 31 teeth.

14. The timepiece display mechanism (20) according to claim 12, characterised in that the timepiece display mechanism (20) is a date display mechanism, the first roller being a ones display roller indirectly driven by the first input wheel (2), the first input wheel (2) being a 31-tooth wheel from which one tooth is removed or from which two consecutive teeth are removed, and the second roller being a tens roller directly driven by a second input wheel (22) pivoted in synchronism with the first input wheel (2), the second input wheel (22) being a truncated 31-tooth wheel retaining only 4 teeth in the positions of 10, 20, 30 and 31 teeth, and the first roller including five of the pivoting flaps (12), five of the pivoting flaps (12) bearing numbers from 0 to 9 on ten of their faces.

15. The timepiece display mechanism (20) according to claim 12, characterised in that the timepiece display mechanism (20) is a date display mechanism, the first roller is a ones display roller indirectly driven by the first input wheel (2), the first input wheel (2) is a 31-tooth wheel from which one tooth is removed or from which two consecutive teeth are removed, and the second roller is a tens roller directly driven by a second input wheel (22) pivoted in synchronism with the first input wheel (2), the second input wheel (22) is a truncated 31-tooth wheel retaining only 4 teeth in the positions of 10, 20, 30 and 31 teeth, and the timepiece display mechanism (20) includes a roller for indicating the day and including one or three pivoting tabs (12).

16. The timepiece display mechanism (20) according to claim 12, characterised in that the timepiece display mechanism (20) is a date display mechanism, the first roller is a ones display roller indirectly driven by the first input wheel (2), the first input wheel (2) is a 31-tooth wheel from which one tooth is removed or from which two consecutive teeth are removed, and the second roller is a tens roller directly driven by a second input wheel (22) pivoted in synchronism with the first input wheel (2), the second input wheel (22) is a truncated 31-tooth wheel retaining only 4 teeth in the positions of 10, 20, 30 and 31 teeth, and the timepiece display mechanism (20) includes a roller for indicating the month and including six pivoting flaps (12).

17. The timepiece display mechanism (20) according to claim 9, wherein the timepiece display mechanism (20) includes a roller for indicating leap years.

18. The timepiece display mechanism (20) according to claim 9, characterised in that the timepiece display mechanism (20) comprises a roller for indicating the phases of the moon arranged to be driven by a wheel having 59 teeth.

19. The timepiece display mechanism (20) according to claim 9, characterised in that the timepiece display mechanism (20) includes a roller for indicating day/night arranged to pivot twice a day.

20. Watch (100) comprising at least one timepiece display mechanism (20) according to claim 2.

Technical Field

The invention concerns an adjustment mechanism for a timepiece display mechanism including at least a first input wheel arranged to directly or indirectly drive a first control wheel for controlling the position of a first display member included in said display mechanism.

The invention also relates to a display mechanism comprising at least one such adjustment mechanism.

The invention also relates to a watch comprising at least one such display mechanism.

The present invention relates to the field of timepiece display mechanisms, and more particularly to the field of display mechanisms for complex functions such as calendars, phases of the moon, time zones or the like.

Background

Swiss patent No.310559 in the name of Fabrique d' Horlogerie de Fontainemelon discloses an independent drive for two date display devices, one for ten and one for 31 days of a month.

Specific arrangements of such roller-type display mechanisms are disclosed in patent applications nos. ch00849/16, EP16177872 and EP17175547 in the name of montes BREGUET SA and will not be described in detail here. In particular, the date is displayed on two rollers, namely a simple roller for the tens position and a roller for the units with five pivoting flaps (flaps), each flap having two faces, which provides a high level of readability of all the displayed numbers.

Disclosure of Invention

The present invention proposes to facilitate the adjustment of complex display mechanisms and to simplify the initial assembly process in a factory.

To this end, the invention relates to an adjustment mechanism for a timepiece display mechanism according to claim 1.

The invention also relates to a display mechanism comprising at least one such adjustment mechanism.

The invention also relates to a watch comprising at least one such display mechanism.

Drawings

Other features and advantages of the present invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:

fig. 1 shows a schematic view from a first side of a timepiece display mechanism with a roller, including an adjustment mechanism according to the invention.

Fig. 2 presents a schematic view of the mechanism of fig. 1 in a cross section through the axis of the planet wheels of the differential mechanism comprised in the adjustment mechanism.

Fig. 3 shows a schematic view of the mechanism of fig. 1, seen from a second side opposite to the first side.

Fig. 4 shows a schematic side view of the roller-type display mechanism of fig. 1.

Fig. 5 shows a schematic perspective view of a part of the roller-type display mechanism of fig. 1, wherein the input wheel is driven by the intermediate wheel.

Fig. 6 is a block diagram showing the function of the differential mechanism.

Figure 7 shows a schematic front view of a watch comprising the roller-type display mechanism of figure 1.

Detailed Description

The invention relates to an adjusting mechanism 10 for a timepiece display mechanism 20. The display mechanism 20 comprises at least a first input wheel 2, which first input wheel 2 is arranged to directly or indirectly drive a first control wheel 3, which first control wheel 3 is used to control the position of a first display member 30 comprised in the display mechanism 20.

According to the invention, the adjustment mechanism 10 comprises a differential gear train mechanism 50, which differential gear train mechanism 50 comprises a drive wheel set 4 held by a display positioning lever (jumper) 40. The drive wheel set 4 is arranged to be pivoted by the first input wheel 2 and is arranged to drive at least one planet wheel 5 in mesh with the first control wheel 3.

The planet wheels 5 are pivotally mounted and eccentric with respect to the planet wheel carrier 6. The planet wheel carrier 6 forms a friction spring and is frictionally mounted in a cavity 62 of the frame 15 of the adjustment mechanism 10 by means of a protrusion 61 included therein, or on a shoulder of said frame 15 by means of internal friction. The differential gear train mechanism 50 is arranged to multiply the rotation between one input and the output of the differential mechanism by a particular given factor, in particular an integer factor, when the other input of the differential mechanism is stationary. When applied to a unit roller of a roller-type display device, this factor is equal to 2 for the non-limiting embodiment shown in the figures; if, for example, it is the case for a ten-digit wheel of the same display device, the ratio can be 1.0 or 0.5.

The planet-wheel carrier 6 comprises a handling device 7, the handling device 7 being arranged to allow the watch technician to release friction to change the angular position of the planet wheels 5, which position affects and determines the position of the first control wheel 3 so that it is correctly indexed (indexing) with respect to at least one other display member 80 of the display mechanism 20. In the non-limiting embodiment shown in the figures, these manoeuvring means 7 comprise two arms which can be manoeuvred with pliers or in other ways; in another embodiment they may comprise holes or lugs arranged to cooperate with a complementary shaped tool such as a snap ring clamp or the like. The steering device 7 can also be used to change the angular position of the planet wheels 5 without affecting the friction, since the effect on the friction is not necessary for the function, but provides comfort of use.

The invention also relates to a display mechanism 20 comprising at least one such adjustment mechanism 10. More specifically, the display mechanism 20 is a momentary or semi-momentary display mechanism and comprises at least one drive wheel set 9, which drive wheel set 9 comprises at least one finger 90, which finger 90 is arranged to directly or indirectly drive the first input wheel 2. The illustrated embodiment relates to a date display mechanism. Such display mechanisms or moon phases or time zones or other display mechanisms generally comprise at least one large wheel with a large number of teeth of small dimensions: 31. 59, 24 teeth, and the interface with the control finger or positioning rod is typically not perfect. Thus, in particular, the first input wheel 2 is a large wheel comprising at least 24 teeth.

In order to increase the safety of the drive function during a conventional drive, in particular tangential drive, of such wheels by means of the fingers, in order to prevent the fingers from also driving the front tooth or one tooth out of drive, and in order to ensure that such large wheels are held firmly in the locked position by the securing lever, so that a misalignment in the event of shocks or accelerations during wear is avoided, it is advantageous to drive and hold the relevant large wheel indirectly by means of the intermediate wheel.

To this end, in particular, display mechanism 20 comprises, between each drive wheel set 9 and first input wheel 2, at least one intermediate wheel 91 comprising a number of teeth less than or equal to half the number of teeth of first input wheel 2. Each finger 90 is arranged to cooperate with an intermediate wheel 91 or with a star wheel 92 pivoted integrally with intermediate wheel 91. The display mechanism 20 comprises at least one input positioning lever 93, a locking position for engagement with only the intermediate wheel 91 or such a star wheel 92; the display mechanism 20 further comprises a positioning correction rod 94, which positioning correction rod 94 also engages only with the intermediate wheel 91 or with such a star wheel 92 for changing position.

More specifically, at least one intermediate wheel 91 pivots integrally with star wheel 92.

More specifically, the display mechanism 20 includes a first drive wheel set 9 as a drive wheel set and a second drive wheel set 9 as a correction wheel set.

More specifically, the at least one intermediate wheel 91 is arranged to move only the first input wheel 2 or the second input wheel 22 or the front wheel 21, which is pivoted synchronously with the first input wheel 2, by one tooth at each position jump of the intermediate wheel 91.

More specifically, the at least one intermediate wheel 91 has a pivot axis that is orthogonal to the pivot axis of the first input wheel 2 or to the pivot axis of the second input wheel 22 that is synchronously pivoted with the first input wheel 2.

More specifically, the display mechanism 20 comprises a second input wheel 22 or a front wheel 21 pivoted synchronously with the first input wheel 2, and as shown, said second input wheel 22 or said front wheel 21 cooperates with at least one intermediate wheel 91.

More specifically, display mechanism 20 comprises a single intermediate wheel 91, this single intermediate wheel 91 being arranged to cooperate with each drive wheel set 9.

The non-limiting example shown in the figures relates to a first input wheel 2 with 31 teeth, the first input wheel 2 comprising one spur tooth, the first input wheel 2 pivoting in synchronism with a second input wheel 22, and the second input wheel 22 being a truncated wheel with 31 teeth, leaving only 4 teeth in positions 10, 20, 30 and 31, and the first input wheel 2 also pivoting in synchronism with a front wheel 21 with 31 teeth. This front wheel 21 makes it possible to vary the axis of rotation, which is necessary for the roller-type display mechanism shown in the figures, since the axis of the roller is parallel to the plane of the bottom plate and perpendicular to the axis of the wheel set of the movement. Intermediate wheel 91 has 12 teeth and cooperates with a 24-hour finger 90 resiliently mounted on drive wheel set 9 in a conventional manner. Here, the intermediate wheel 91 is coaxial and synchronized with the 12-tooth date star wheel 92. A date finger (not shown) driven by the timepiece movement operates once a day at midnight with the date star wheel 92 to complete 1/12 revolutions of the step. The intermediate wheel 91 is set at 12: the gear ratio of 31 drives the 31-tooth front wheel 21 to complete 1/31-turn jumps. Since the date star wheel 92 here has only 12 teeth, the drive function has a significantly increased safety feature compared to a conventional direct drive mechanism on a wheel with 31 teeth, and the locking function using a jumper is similarly improved. If NIHS (swiss clock industry standard) teeth are used, there may be only one intermediate wheel 91 with a star wheel 92, the tines of which allow both finger drive and positioning by a positioning rod.

In the particular application of the invention illustrated in the figures, the display mechanism 20 is a display mechanism having a roller, wherein the first display member 30 is a first roller and the at least one other display member 80 is a second roller, in particular but not exclusively coaxial with the first roller.

The patent applications CH00849/16, EP16177872 and EP17175547 of the same applicant disclose specific arrangements of such roller-type display mechanisms, which are not described in detail here. In particular, the date is displayed on two rollers, namely a simple roller for the tens position and a roller for the units with five pivoting tabs, each tab having two faces, which provides a high level of readability of all the displayed numbers. This unit display is done on two turns of the wheel, in contrast to the display of the unit wheel of CH310559, which only completes one turn. The solution of driving a 5-tooth star wheel is not geometrically optimal, in particular in terms of the creation of at least one missing tooth from 31 to 01 across. The advantageous solutions cited in patent applications CH00849/16, EP16177872 and EP17175547 multiply the rotation of the star wheel with the greater number of teeth, here the star wheel with 10 teeth forming the drive wheel set 4, by an integer factor, here a factor of 2, by means of a multiplier wheel set interposed between the ten-tooth star wheel and the roller.

The multiplier gear train, particularly the 2-fold multiplier, requires indexing in order to display the ones digits facing the tens digits. Since the gear train is a multiplication gear train, this indexing function requires extremely high precision. The assembly process must also be simplified, since any design of precise angular indexing of the train presents difficulties for the watchman who is responsible for the assembly operation or for the after-market adjustment.

More specifically, when it is coaxial, the second roller is arranged to be driven directly or indirectly by the first input wheel 2 or by the second input wheel 22, which is pivoted synchronously with the first input wheel 2.

More specifically, the coaxial second roller is arranged to be directly or indirectly driven by a second input wheel 22 pivoted in synchronism with the first input wheel 2 and having an incomplete ring gear.

More specifically, the first roller comprises at least one tab 12 with two faces, which has two display symbols on both sides, the tab 12 being pivoted integrally with a pinion 13, the pinion 13 being arranged to pivot when it meshes with a toothed section 14 comprised in a frame 15 of the display mechanism 20.

More specifically, the display mechanism 20 is a date display mechanism, and the first wheel is a ones display wheel indirectly driven by the first input wheel 2, and the first input wheel 2 is a 31-tooth wheel in which one tooth (remaining 30 teeth) is removed or two consecutive teeth (remaining 29 teeth) are removed. The second roller is then a tens roller, directly driven by the second input wheel 22, the second input wheel 22 pivoting in synchronism with the first input wheel 2 and being a truncated 31-tooth wheel leaving only 4 teeth in positions 10, 20, 30 and 31.

Fig. 6 schematically shows the differential gear train mechanism 50:

-A: indexing and multiplication (here by a factor of 2);

-B: driving a unit ten-tooth star wheel, and 1/10 revolutions per day;

-C: a bit display;

-D: an index located on the friction spring.

The differential gear train directly allows multiplication by 2 between the first input and the output when the second input is stationary.

Rotation on the second input causes the units roller to rotate independently of the ten-tooth star wheel and aligns the units display with the tens display.

In the particular embodiment in which the clamping means 7 of the friction-mounted planet wheel carrier 6 is located inside the watch case, this rotation is ensured by friction or by a locking function, so that rotation can only occur when adjusted by the watch technician.

The differential gear train may advantageously be placed concentrically with the unit rollers, but this embodiment is not limiting.

Fig. 2 shows a kinematic chain. A star wheel 92 integral with intermediate wheel 91 drives front wheel 21 and therefore first input wheel 2, which first input wheel 2 is arranged to drive wheel set 4 via a ten-tooth star wheel 42. The drive wheel set 4 comprises a plate 41 which is integral with a ten-tooth star wheel 42, which plate 41 has 25 teeth here and meshes with a pinion 51 of the planet wheels 5 of a spindle 51, which planet wheels 5 have 10 teeth here, which planet wheels 5 are pivoted relative to the planet wheel carrier 6. The planet wheels 5 comprise a plate 53 which meshes with the first control wheel 3, the plate 53 having 16 teeth here, and the first control wheel 3 being the pinion of the first roller 30 here and having 20 teeth. The second input wheel 22 is arranged to mesh with a pinion 81 of a spindle 82 of a second roller 80.

When the arbour of the planet 5 is kept stationary by friction (normal operation at date jump), the rotation NR of the first roller 30 as a function of the rotation NE of the driving wheel set 4 (ten-tooth star) is equal in this particular and non-limiting example to: NR _ NE _ 25/10 _ 16/20 _ 2 _ 0.1 _ 0.2.

More specifically, the first roller has five pivoting flaps 12 with numbers from 0 to 9 on ten of its faces. Therefore, 1/5 revolutions per day are suitably performed.

When the driving wheel set 4 (ten-tooth star wheel) is immobilized by its positioning rod 40, i.e. in normal operation between midnight and 23:30, one of the elements of the differential calculation becomes zero and the rotation NR is calculated as a function of the manipulation NF (═ 38 °) of the friction spring by the watchmaker as:

NR＝NF*20*10/(20*10–16*25)＝-38°。

a rotation of 38 ° (+/-19 °) is suitably performed and is correct and sufficient for any indexing of the assembly: one tooth of the first control wheel 3 corresponds to 360 °/20 — 18 °.

The friction spring is released by operating the gripping means 7, which gripping means 7 are radial elements in the figure.

More specifically, the display mechanism 20 also includes a roller for indicating the day of the week and includes one or three pivoting flaps 12.

More specifically, the display mechanism 20 includes a roller for indicating the month and includes six pivoting flaps 12.

More specifically, the display mechanism 20 includes a scroll wheel for indicating leap years.

More specifically, the display mechanism 20 comprises a wheel for indicating the phases of the moon, which is arranged to be driven by a wheel having 59 teeth.

More specifically, the display mechanism 20 comprises a roller for indicating day/night, which is arranged to pivot twice a day.

In short, as shown, the present invention makes it possible to rotate the rollers with respect to a ten-tooth star wheel, which allows a perfect alignment of the numbers or symbols comprised on the respective rollers with respect to each other.

In the application of the conventional flat panel display mechanism, the friction spring according to the present invention greatly facilitates the adjustment of the calendar, for example, for the display of the annual date.

The invention is described herein in a particular application in which the holding means 7 are accessible only by the watch technician and therefore preferably inside the watch case, but it is clear that these holding means can also be placed outside the watch case for operation by the user, provided they are equipped with the necessary sealing means. The application of static timepieces, such as clocks, does not require very complex sealing means and is easily achieved with the adjustment mechanism according to the invention using a differential gear and a friction spring.

This friction assembly of the planet wheel carrier 6 is advantageous because it avoids the usual prior adjustment and, in the case of the particular illustration of the roller-type display device, it avoids having to index the roller pinion 3 on the roller 30, the wheel of the reduction wheel set on its pinion and the wheel of the ten-tooth star on the star wheel. The three wheel sets can thus be assembled without any particular indexing, which represents a significant saving in terms of time and expertise. The invention avoids having to index the wheel set during assembly of the roller, the parts being roughly assembled and adjusted after assembly.

The invention is particularly applicable to perpetual calendar mechanisms.

The invention also relates to a watch 100 comprising at least one such display mechanism 20.