A watch movement equipped with a planetary gear mechanism and a power reserve indicator.
The planetary mechanism in the power reserve display device addresses the inefficiencies of existing devices by reducing components and volume, enabling a compact and efficient power reserve indication.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- MONTRES BREGUET SA
- Filing Date
- 2025-09-09
- Publication Date
- 2026-06-30
AI Technical Summary
Existing power reserve display devices in timepiece movements require numerous components, increasing cost and volume, which is inefficient.
A timepiece movement incorporating a power reserve display device with a planetary mechanism that reduces the number of components and volume by using a differential gear and planetary mechanism to achieve a large reduction ratio.
The solution significantly reduces the number of components and volume required for the power reserve display, allowing for a compact and efficient power reserve indication.
Smart Images
Figure 2026108515000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of horology, and more particularly to a timepiece movement comprising a device for displaying a power reserve with a planetary mechanism.
Background Art
[0002] In a timepiece movement, a power reserve display device is a complication of the timepiece that enables the user to know the level of energy available for timekeeping or any other time display. In other words, the power reserve display device makes it possible to indicate the charge level of the barrel(s) in the timepiece movement.
[0003] The power reserve display device comprises a power reserve indicator such as a pointer and a differential gear that connects the indicator to the barrel(s), as described in patent document EP3333637.
[0004] The power reserve display device generally comprises a number of components in order to display an appropriate reduction ratio between the barrel(s) in the timepiece movement and the power reserve indicator. These numerous components greatly affect the cost of the timepiece movement in which they are incorporated and require a significant volume for incorporating the power reserve display device within the timepiece movement.
Summary of the Invention
[0005] The present invention addresses the aforementioned drawbacks by providing a timepiece movement comprising at least one barrel and a device for displaying a power reserve. The power reserve display device comprises a winding mechanism comprising a series of winding wheels, a reduction gear train meshing with the barrel or one of the barrels, and a differential gear arranged to kinematically connect the winding wheel series and the barrel via a first input of the differential gear. The differential gear comprises a second input connected by the reduction gear train and an output. The first input, the second input and the output in the differential gear are preferably arranged coaxially with each other.
[0006] The power reserve display device further comprises a power reserve display module including a planetary mechanism that engages with the output of the differential gear.
[0007] These features allow for a favorable reduction in the number of components in the power reserve display device, thereby reducing its overall volume.
[0008] Furthermore, the planetary mechanism allows for a relatively large reduction ratio between the (multiple) mainspring barrels and the indicator on the power reserve indicator module within a relatively small volume.
[0009] In some embodiments, the present invention may further comprise one or more of the following features, either individually or in any technically possible combination.
[0010] In some embodiments, the planetary mechanism comprises a planetary input gear with planetary small gears that are driven on the planetary axis and engage with the satellites. The planetary mechanism further comprises a crown fixed to a structure within the watch movement, the crown having internal teeth that mesh with the satellites.
[0011] The satellite is supported by a satellite carrier that can rotate planetary output gears around the planetary axis.
[0012] In some embodiments, the satellite carrier may be friction-fitted to the planetary output gear.
[0013] In some embodiments, the power reserve indicator module includes a power reserve indicator shaft that is rotatably positioned within the crown and rotatably fixed to the planetary output gear so that the rotation of the planetary output gear causes the power reserve indicator shaft to rotate.
[0014] In some embodiments, the differential gear comprises a differential gear satellite supported by a differential gear satellite carrier fixed to rotate freely on the differential gear shaft, the differential gear satellite carrier constituting a first input to the differential gear and meshing with the mainspring barrel.
[0015] In some embodiments, the second input of the differential gear is comprised of a solar mobile rotatably mounted on the differential gear shaft, the solar mobile comprising a solar gear that meshes with the reduction gear train and a solar subgear that meshes with the differential gear satellite.
[0016] In some embodiments, the output of the differential gear consists of a first output vehicle and a second output vehicle that are fixed to the differential gear shaft in the rotational direction.
[0017] In some embodiments, the planetary mechanism engages the output of the differential gear via a reduction mobile, the reduction mobile comprising a reduction gear that meshes with the second output gear on the differential gear, and a reduction gear that meshes with the planetary input gear.
[0018] In some embodiments, the clock movement comprises a first barrel and a second barrel, each having a ratchet wheel, both of which mesh with intermediate gears, the first barrel having a drum connecting it to the differential gear, and the second barrel having a drum connecting it to the reduction gear train. [Brief explanation of the drawing]
[0019] Other features and advantages will become apparent from the following detailed description, which is shown as a non-limiting example and with reference to the attached drawings. [Figure 1] This is a view from below of two mainsprings and a power reserve indicator device in a watch movement according to a preferred exemplary embodiment of the present invention. [Figure 2]Perspective view from above of an apparatus for displaying two scent boxes and power reserve in a timepiece movement according to a preferred exemplary embodiment of the present invention. [Figure 3] It is an enlarged view of FIG. 2, where the differential gear and planetary mechanism on the display device can be seen. [Figure 4] It is a cross-sectional view of the differential gear on the power reserve display device of FIG. 3. [Figure 5] It is a cross-sectional view of the planetary mechanism on the power reserve display device of FIG. 3.
[0020] Note that the drawings are not necessarily drawn to scale for clarity.
Mode for Carrying Out the Invention
[0021] FIGS. 1 and 2 show an apparatus 10 for displaying two scent boxes and power reserve in a timepiece movement according to a preferred exemplary embodiment of the present invention.
[0022] As shown in FIG. 1, the timepiece movement according to the present invention comprises a first scent box 11 and a second scent box 12 that are kinematically connected to each other by an intermediate gear 20 and each have a scent box spring, in a manner well known to those skilled in the art.
[0023] More specifically, the first and second scent boxes 11 and 12 each comprise drums 110 and 120, and angular hole wheels 111 and 12b that both preferably mesh with the intermediate gear 20.
[0024] The drum 110 on the first scent box 11 engages with a pawl 21, whereby the drum 110 is locked in one direction of rotation by the pawl 21 in a manner well known to those skilled in the art. The spring in the second scent box 12 is unwound in a manner well known to those skilled in the art when the timepiece movement is operating, and rotates a finishing gear train (not shown) via the drum 120.
[0025] The device 10 for displaying power reserve comprises a differential gear 13 kinematically inserted between the winding wheel train 22 on the winding mechanism and the first perfume box 11. That is, the differential gear 13 is arranged to kinematically connect the winding wheel train 22 and the first perfume box 11.
[0026] The winding mechanism may be operated via a winding fuse connected to the winding stem and / or via a rotating weight. The winding mechanism is well-known per se to those skilled in the art and will not be described in further detail hereinafter.
[0027] The differential gear 13 engages with the drum 110 on the first perfume box 11 via a first input. In the exemplary embodiment of the invention shown in the drawings, the first input consists of a differential gear satellite carrier 130 that supports the differential gear satellite 131. More specifically, the differential gear 13 comprises a differential gear shaft 132, and the differential gear satellite carrier 130 is mounted on the differential gear shaft 132 so as to rotate freely. This is particularly shown in FIG. 4.
[0028] The differential gear 13 further comprises a second input connected to the second perfume box 12 by a reduction gear train 15. The second input consists of a sun mobile 133 mounted on the differential gear shaft 132 so as to rotate freely, and the sun mobile 133 comprises a sun gear 1331 meshing with the reduction gear train 15 and a sun pinion meshing with the differential gear satellite 131.
[0029] The springs in the first and second perfume boxes, 11 and 12, are wound up when the drum 110 on the first perfume box 11 is driven in a predetermined rotational direction by the differential gear satellite carrier 130 after the winding wheel train 22 has acted in the winding direction.
[0030] As shown in Figure 4, the differential gear 13 has an output consisting of a first output vehicle 134 and a second output vehicle 135 driven on the differential gear shaft 132. The first output vehicle 134 meshes with the differential gear satellite 131, thereby allowing the differential gear satellite 131 to roll around the first output vehicle 134 or to rotate the first output vehicle 134.
[0031] Advantageously, the first and second inputs on the differential gear 13, as well as the first and second output gears 134 and 135, are arranged coaxially with each other. This feature reduces the volume that the differential gear 13 occupies within the clock movement. This particularly compact arrangement reduces the volume required within the clock movement to incorporate the differential gear 13.
[0032] The power reserve display device 10 comprises a power reserve display module 16 that engages with the output of the differential gear 13, more specifically, with the second output vehicle 135. In particular, the second output vehicle 135 is coupled to a planetary gear mechanism 160 in the power reserve display module 16, preferably via a reduction mobile 17, as shown in detail in Figure 4.
[0033] In the exemplary embodiments shown in the drawings, particularly as shown in Figure 5, the planetary mechanism 160 comprises a planetary input gear 161 that meshes with a reduction mobile 17. The planetary input gear 161 is driven on a planetary shaft 162, which comprises a planetary small gear that engages with a satellite 163 supported by a satellite carrier 164.
[0034] In particular, the reduction gear mobile 17 includes a reduction gear that meshes with a second output gear 135 on the differential gear 13, and a reduction gear that meshes with a planetary input gear 161.
[0035] The planetary mechanism 160 further includes a crown 165 with internal teeth that mesh with the satellite 163. As shown in Figures 2 and 3, the crown 165 is fixed without any degree of freedom to a structure within the watch movement, such as a bar or bridge.
[0036] The planetary gear 160 further includes a planetary output gear 166 that can rotate around the planetary axis 162. More specifically, the planetary output gear 166 is mounted to rotate freely on the planetary axis 162.
[0037] As shown in Figures 2, 3, and 5, the satellite carrier 164 is preferably friction-fitted to the planetary output gear 166. Thus, the satellite carrier 164 transmits torque to the planetary output gear 166, causing the planetary output gear 166 to rotate to the maximum torque at which the satellite carrier 164 slides on the planetary output gear 166.
[0038] In exemplary embodiments of the present invention shown in the drawings, particularly in Figures 3 to 5, the satellite carrier 164 comprises a rim supporting the satellite 163 and two elastic arms whose ends are connected to the rim. The elastic arms are positioned to define holes into which the annular portions of the planetary output gear 166 engage.
[0039] Advantageously, the power reserve indicator module 16 includes a power reserve indicator shaft 167 rotatably positioned within the crown 165, i.e., within the body of the components forming the crown 165, as shown particularly in Figures 3 and 5. This power reserve indicator shaft 167 is rotatably fixed to a planetary output gear 166, so that the rotation of the planetary output gear 166 causes the power reserve indicator shaft 167 to rotate. More specifically, a rack 168 is attached to the power reserve indicator shaft 167 and meshes with the planetary output gear 166. An indicator (not shown), such as a needle or disc, is fixed to the power reserve indicator shaft 167.
[0040] Advantageously, the power reserve indicator module 16 includes a spring 169 positioned to contact the power reserve indicator shaft 167 and to impart a return stress to the power reserve indicator shaft 167. In particular, the rack 168 may have a notch that accommodates one end of the spring 169.
[0041] Typically, the power reserve indicator shaft 167 has two extreme angular positions, one indicating that the mainspring is fully wound and the other indicating that the mainspring is fully unwound. These extreme angular positions are defined, for example, by a stopper fixed to the crown 165, or by a stopper (not shown) fixed to a structure within the watch movement such as a mainplate or bar, and are configured to contact the power reserve indicator shaft 167, particularly the rack 168.
[0042] In short, when the winding gear train 22 is acted upon in the winding direction, the drum 110 on the first barrel 11 is rotated by the differential gear satellite carrier 130, as shown by the thick arrows in the drawing. The differential gear satellite carrier 130 drives the differential gear satellite 131 in circular motion around the differential gear shaft 132. The differential gear satellite 131 then rotates around the first output wheel 134, causing it to rotate, and also rolls around the sun gear without transmitting any motion to the sun gear.
[0043] The second output vehicle 135 is rotated by the first output vehicle 134, which rotates the planetary input gear 161 via the reduction mobile 17. In particular, as shown in Figure 5, when the planetary input gear 161 rotates, it rotates the satellite 163 around its axis and around the planetary axis 162, thereby rotating the satellite carrier 164. The satellite carrier 164 transmits torque to the planetary output gear 166 by friction, which rotates the planetary output gear 166, causing the rack 168 to rotate, and as a result the power reserve indicator shaft 167 to move.
[0044] The power reserve indicator shaft 167 is driven in a direction that indicates an increase in the power reserve.
[0045] This operation continues until the power reserve indicator shaft 167 reaches one of its extreme angular positions, at which point the satellite carrier 164 slips relative to the planetary output gear 166 due to the rack 168 being locked in the rotational direction by the stopper.
[0046] During the above operation, the second barrel 12 is gradually wound up by the first barrel 11. In particular, when the spring in the second barrel 12 is sufficiently wound up, it rotates the drum 120 on the second barrel 12, releasing the finishing gear train and thereby starting the watch movement. The rotation of the drum 120 on the second barrel 12 rotates the sun gear 1331 via the reduction gear train 15.
[0047] Furthermore, when the winding gear train 22 is not in operation and the springs in the first and second barrels 11 and 12 are unwound, that is, when the watch movement is operating, the drum 120 on the second barrel 12 transmits rotational motion to the sun gear 1331 and the differential gear satellite 131 via the reduction gear train 15, as described above.
[0048] When the differential gear satellite 131 rotates, it rotates the first differential gear output vehicle 134, which in turn rotates the second differential gear output vehicle 135. The planetary input gear 161 is then rotated by the reduction mobile 17, which drives the satellite carrier 164 via the satellite 163.
[0049] Similarly, the satellite carrier 164 transmits torque to the planetary output gear 166 by friction, causing the planetary output gear 166 to rotate, which in turn causes the rack 168 to rotate, and as a result the power reserve indicator shaft 167 to move.
[0050] The power reserve indicator shaft 167 is driven in a direction that indicates a decrease in the power reserve.
[0051] The arrangement of the differential gear 13 and the planetary gear mechanism 160 makes it advantageous to provide a large reduction ratio within a limited volume between the rotation of the drum 110 on the first mainspring 11 and the rotation of the power reserve indicator when the spring in the first mainspring 11 is wound up. For example, the power reserve indicator may be driven only for a portion of the rotation, such as 0.1 to 0.2 rotations, when the drum 110 on the first mainspring 11 is driven for several tens of rotations, for example from 25 to 30 rotations.
[0052] Similarly, while the springs in the first and second barrels 11 and 12 are unwound, the arrangement of the reduction gear train 15, and the differential gear 13 and planetary gear mechanism 160, may cause the drum 120 on the second barrel 12 to rotate for several tens of revolutions, for example, 25 to 30 revolutions, and the power reserve indicator may rotate by a fraction of a revolution, such as between 0.1 and 0.2 revolutions.
[0053] In another exemplary embodiment of the present invention not shown in the drawings, the watch movement according to the present invention may be intended to comprise a single barrel with a barrel spring in a manner well known to those skilled in the art. This barrel further comprises a drum and a ratchet wheel.
[0054] In this exemplary embodiment, the ratchet wheel is kinematically coupled to a satellite carrier on the differential gear so that it is rotated by the satellite carrier on the differential gear when the winding gear train 22 is acted upon in the winding direction. This feature allows the barrel spring to be wound up. In this exemplary embodiment, an intermediate gear 20 is inserted between the ratchet wheel and the differential gear satellite carrier.
[0055] Similarly, the ratchet wheel engages with the pawl so that it is locked in the direction of rotation when the watch movement is running. Then, under the action of the unwinding of the barrel spring, only the drum is rotated.
[0056] The drum is connected via the reduction gear train 15 to a second input on the differential gear 13, namely the sun gear 1331.
[0057] More generally, the embodiments and uses discussed above are described as non-limiting examples, and it should be noted that other modifications are possible.
[0058] In particular, the power reserve indicator module 16 includes at least one intermediate gear that meshes with a mobile bearing a power reserve indicator, thereby enabling the power reserve indicator to be shifted.
Claims
1. A watch movement comprising at least one mainspring barrel (11, 12) and a power reserve indicator (10), wherein the device is A winding mechanism equipped with a winding gear train (22), A reduction gear train (15) that meshes with one of the aforementioned barrels (11, 12), A differential gear (13) is arranged to kinematically connect the winding gear train (22) and the mainspring barrel (11) via a first input in the differential gear (13), wherein the differential gear has a second input and output, and the differential gear is connected to the reduction gear train (15) by the second input, A power reserve indicator module (16) is provided with a planetary mechanism (160) that engages with the output of the differential gear (13) and A watch movement equipped with [a specific feature / feature].
2. The watch movement according to claim 1, wherein the planetary mechanism (160) comprises a planetary small gear that engages with a satellite (163) and a planetary input gear (161) that is driven on a planetary shaft (162), the planetary mechanism (160) further comprises a crown (165) that is fixed to a structure within the watch movement and has internal teeth that mesh with the satellite (163), and the planetary mechanism (160) comprises a satellite carrier (164) that supports the satellite (163) and is capable of rotating a planetary output small gear (166) around the planetary shaft (162).
3. The watch movement according to claim 2, wherein the power reserve indicator module (16) is rotatably arranged within the crown (165) and includes a power reserve indicator shaft (167) fixed in the rotational direction to the planetary output gear (166), so that the rotation of the planetary output gear (166) causes the power reserve indicator shaft (167) to rotate.
4. The watch movement according to claim 2, wherein the satellite carrier (164) is friction-fitted to the planetary output gear (166).
5. The watch movement according to claim 1, wherein the differential gear (13) comprises a differential gear satellite (131) supported by a differential gear satellite carrier (130) mounted to rotate freely on a differential gear shaft (132), the differential gear satellite carrier (130) constitutes the first input to the differential gear (13) and meshes with the mainspring barrel (11).
6. The clock movement according to claim 5, wherein the second input in the differential gear (13) is comprised of a solar mobile (133) rotatably mounted on the differential gear shaft (132), the solar mobile (133) comprising a solar gear (1331) that meshes with the reduction gear train (15) and a solar subgear that meshes with the differential gear satellite (131).
7. The clock movement according to claim 5, wherein the output in the differential gear (13) is provided by first and second output vehicles (134, 135) fixed to the differential gear shaft (132) in the rotational direction.
8. The clock movement according to claim 2, wherein the output in the differential gear (13) is composed of first and second output wheels (134, 135) fixed in the rotational direction to the differential gear shaft (132), the planetary mechanism (160) engages with the output in the differential gear (13) via a reduction mobile (17), and the reduction mobile (17) comprises a reduction gear that meshes with the second output wheel (135) in the differential gear (13) and a reduction gear that meshes with the planetary input gear (161).
9. A watch movement according to claim 1, comprising first and second barrels (11, 12), each comprising a ratchet wheel (111, 121), the ratchet wheels (111, 121) both meshing with an intermediate gear (20), the first barrel (11) comprising a drum (110) connected to the differential gear (13), and the second barrel (12) comprising a drum (120) connected to the reduction gear train (15).