Horological display mechanism with an elastic hand

Patent metadata

Field	Value
Publication number	US-11774909-B2
Application number	US-202117186146-A
Country	US
Kind code	B2
Filing date	Feb 26, 2021
Priority date	Jul 31, 2018
Publication date	Oct 3, 2023
Grant date	Oct 3, 2023

Abstract

A horological display mechanism with an elastic hand ( 1 ) for driving, about a shaft (D), pipes mounted at the ends of a flexible blade ( 3 ), arranged to deform the flexible blade ( 3 ), including a mechanism acting on the drive train of the first pipe ( 2 ) and of the second pipe ( 4 ) and which includes two planetary wheels ( 82; 84 ) for driving the pipes ( 2; 4 ), and an input planet-carrier chassis ( 180 ) for driving the hand ( 1 ), and rotatable with a regulation cam ( 801 ), the track ( 802 ) of which includes a rising edge and falling edge. An elastic arm ( 803 ) has a distal end which cooperates with the track and a rising edge of which raises the elastic arm ( 803 ) away from the axis of the cam to consume torque, and a falling edge which makes the elastic arm move back towards the axis to restore torque to the system.

First claim

The invention claimed is:

1. A horological display mechanism with a variable geometry, including at least one elastic hand which includes a first drive pipe rigidly connected to a first end of a flexible blade, and a second drive pipe rigidly connected to another end of said flexible blade, and including a display index which, in an unstressed free state of said elastic hand in which both said first pipe and said second pipe are not subjected to any stress and are distant from one another, is distant from said first pipe and from said second pipe, a service position of said elastic hand being a stressed position in which said first pipe and said second pipe are coaxial to one another about an output shaft, said display mechanism including first means for driving said first pipe about said output shaft, and second means for driving said second pipe about said output shaft, said first drive means and second drive means being arranged to deform said flexible blade, by varying an angular position of said second pipe with respect to an angular position of said first pipe about said output shaft, and to vary a radial position of said display index with respect to said output shaft, wherein said display mechanism includes at least one mechanism of a differential type acting on a drive train of the first pipe and on a drive train of said second pipe and wherein said differential mechanism includes at least a first planetary wheel for driving said first pipe and/or a second planetary wheel for driving said second pipe, and at least one input planet-carrier chassis driven in rotation by motor means for driving said elastic hand, and wherein said display mechanism includes a torque-regulating mechanism acting on said input planet-carrier chassis.

2. The display mechanism according to claim 1 , wherein said torque-regulating mechanism includes, constrained to rotate with said input planet-carrier chassis, a regulation cam, a track of which comprises a continuous rising edge and falling edge, wherein said torque-regulating mechanism includes an elastic arm, a distal end of which, or a runner carried by said distal end opposite to a recess of the elastic arm, permanently cooperates with said track, the rising edge of which raises said elastic arm and moves the elastic arm away from an axis of rotation of said cam to consume torque, and the falling edge of which makes said elastic arm move back down towards the axis of rotation of said cam to restore torque to the system.

3. The display mechanism according to claim 2 , wherein said track is symmetrical with respect to a plane passing through said output shaft) of the input planet carrier.

4. The display mechanism according to claim 3 , wherein said track has an ovoid profile.

5. The display mechanism according to claim 1 , wherein said input planet-carrier chassis is mounted free in rotation about said output shaft, and includes a first pivot and a second pivot respectively carrying an intermediate wheel and a planetary wheel meshing with one another by a toothing of the intermediate wheel and a toothing of the planetary wheel, said planetary wheel including an eccentric finger, which is arranged to travel over an inner track of a fixed cam, and which is returned against said inner track by the elasticity of said elastic hand, said input planet-carrier chassis including an input toothing, and a shaft that carries, coaxial according to said output shaft, a first cannon-pinion including said first pipe and a second cannon-pinion including said second pipe, wherein a toothing of the second cannon-pinion meshes with the toothing of said intermediate wheel, and wherein a toothing of the first cannon-pinion meshes with the toothing of said planetary wheel.

6. A horological movement including at least one display mechanism according to claim 1 .

7. A watch including at least one horological movement according to claim 6 .

Assignees

• Montres Breguet Sa

Inventors

• Bifrare Christophe

Classifications

• G04B19/02 Primary

  Back-gearing arrangements between gear train and hands {(transmissions in general G04B13/00)} · CPC title

• G04B9/005

  by optical indication of the amount of winding · CPC title

• G04B13/001 Primary

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

• G04B13/007

  with differential work · CPC title

• G04B13/008

  Differentials · CPC title