Timepiece display mechanism with a resilient hand

Patent metadata

Field	Value
Publication number	US-11537080-B2
Application number	US-202016820791-A
Country	US
Kind code	B2
Filing date	Mar 17, 2020
Priority date	Jul 31, 2018
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A timepiece display mechanism with a resilient hand including a first and second device for driving, about an output axis, a first and a second pipe mounted at the ends of a flexible strip, and including a display index distant from the pipes, these drive devices being arranged to deform the flexible strip, by varying the angular position of one pipe with respect to the other about the output axis, and to vary the radial position of the display index with respect to this axis, this mechanism includes a first differential on the drive train of the first pipe, one input of which is formed by a first cam, and a second differential on the drive train of the second pipe, one input of which is formed by a second cam.

First claim

The invention claimed is:

1. A timepiece display mechanism of variable geometry, comprising at least one resilient hand, which includes a first drive pipe integral with a first end of a flexible strip and a second drive pipe integral with another end of said flexible strip, and comprising a display index which, in an unconstrained free state of said resilient hand wherein said first pipe and said second pipe are not subject to any stress and are distant from one another, is distant from said first pipe and said second pipe, the operating position of said resilient hand being a constrained position wherein said first pipe and said second pipe are coaxial to one another about an output axis, said display mechanism comprising first means for driving said first pipe about said output axis and second means for driving said second pipe about said output axis, said first drive means and second drive means being arranged to deform said flexible strip, by varying the angular position of said second pipe with respect to the angular position of said first pipe about said output axis, and to vary the radial position of said display index with respect to said output axis, wherein said display mechanism comprises a first differential on the drive train of said first pipe having one input which is formed by a first cam, and a second differential on the drive train of said second pipe having one input which is formed by a second cam, and wherein said first differential and said second differential carry planets each comprising an off-centre feeler arranged to follow its respective cam.

2. The display mechanism according to claim 1 , wherein said second cam is synchronous with said first cam.

3. The display mechanism according to claim 1 , wherein said first differential and said second differential have a common planet carrier frame or two synchronous planet carrier frames, each carrying planets, which each have an off-centre feeler arranged to follow its respective cam.

4. The display mechanism according to claim 3 , wherein at least one of said cams is distinct from said common planet carrier frame or from said two synchronous planet carrier frames.

5. The display mechanism according to claim 4 , wherein both of said cams are distinct from each other and from said common planet carrier frame or from said two synchronous planet carrier frames.

6. The display mechanism according to claim 3 , wherein at least one of said cams is carried by said common planet carrier frame or one of said two synchronous planet carrier frames.

7. The display mechanism according to claim 1 , wherein said first cam and said second cam are fixed with respect to a plate or a bridge comprised in said display mechanism, and wherein said common planet carrier frame or said two synchronous planet carrier frames is or are driven by a control mechanism of said display mechanism.

8. The display mechanism according to claim 1 , wherein said first cam and said second cam pivot and are synchronous, and wherein said common planet carrier frame or said two planet carrier frames is or are fixed with respect to a plate or a bridge comprised in said display mechanism.

9. The display mechanism according to claim 8 , wherein said display mechanism comprises an on-demand control mechanism for pivoting together said first cam and said second cam, and for varying the radial extension of said resilient hand with respect to said output axis.

10. The display mechanism according to claim 1 , wherein said first cam and said second cam pivot and are synchronous, and wherein said common planet carrier frame or said two synchronous planet carrier frames pivot coaxially with respect to said first cam and said second cam.

11. The display mechanism according to claim 10 , wherein said display mechanism comprises an on-demand control mechanism for pivoting together said first cam and said second cam, and for varying the radial extension of said resilient hand with respect to said output axis.

12. The display mechanism according to claim 1 , wherein said first drive means or said second drive means are arranged to drive another input of an input differential, which is one of said first differential or said second differential, formed by a first planet of said input differential, said first planet being mounted to rotate freely on an input frame mounted to rotate freely about said output axis, and the sun pinion of said input differential being formed by a first toothing carried by said first pipe when said input differential is said first differential, or by a second toothing carried by said second pipe when said input differential is said second differential.

13. The display mechanism according to claim 12 , wherein the other of said first differential and second differential is an output differential, another input of which is formed by a second planet of said output differential, said second planet being mounted to rotate freely on said input frame or on an output frame mounted to rotate freely about said output axis and synchronous with said input frame, and the sun pinion of said output differential being formed by a second toothing carried by said second pipe when said input differential is said first differential, or by a first toothing carried by said first pipe when said input differential is said second differential.

14. The display mechanism according to claim 13 , wherein said second planet is mounted to rotate freely on said input frame, on the face opposite to that which carries said first planet.

15. The display mechanism according to claim 12 , wherein said first planet projects radially with reference to said output axis and with respect to said first fixed cam and to said second fixed cam, and is arranged to cooperate with an internally toothed ring, comprised in said display mechanism, for driving said at least one resilient hand.

16. The display mechanism according to claim 1 , wherein said first differential includes a first planet comprising a first off-centre finger arranged to traverse a first inner path of said first cam and pressed against said first inner path by the resilience of said resilient finger, and wherein said second differential comprises a second planet comprising a second off-centre finger arranged to traverse a second inner path of said second cam and pressed against said second inner path by the resilience of said resilient hand.

17. The display mechanism according to claim 1 , wherein said first cam is fixed in an indexed manner to said second cam with which it forms a case containing said first pipe, said second pipe, and, inserted to rotate freely between said first cam and said second cam, either a single input frame carrying all the wheel sets of said first differential and of said second differential, or an input frame carrying all the wheel sets of said first differential and an output frame mounted to rotate freely about said output axis and synchronous with said input frame and carrying all the wheel sets of said second differential.

18. A timepiece movement including at least one display mechanism according to claim 1 .

19. A watch comprising at least one movement according to claim 18 .

Assignees

• Montres Breguet Sa

Inventors

• Bifrare Christophe
• Zaugg Alain
• Golay Patrice
• Stranczl Marc

Classifications

• G04B19/082

  varying from the normal closed scale · CPC title

• G04B19/042

  Construction and manufacture of the hands; arrangements for increasing reading accuracy (hands with illumination G04B19/305; specially shaped hands, e.g. figures or pictures G04B45/0061; clockwork in the hands G04B45/043; invisible drive of the hands G04B45/046) · CPC title

• G04B13/007

  with differential work · CPC title

• G04B13/001 Primary

  with the choice of adjustable or varying transmission ratio · CPC title

• G04B45/0061

  Moving parts of the clockwork, e.g. pendulum, hands in special form, mostly constructed as a figure (cases and non moving parts of the clockwork in various forms G04B45/0069; decoration and manufacturing methods therefor, also for moving parts G04B45/0076; construction of normal pendulums G04B17/02; construction of normal hands G04B19/042) · CPC title