Wheel with reduced mechanical friction for timepieces

Patent metadata

Field	Value
Publication number	US-10558170-B2
Application number	US-201615355567-A
Country	US
Kind code	B2
Filing date	Nov 18, 2016
Priority date	Dec 18, 2015
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A sequencer mechanism including a rotatably driven locking wheel set including a peripheral holding surface of regular geometry or respectively of regular uniform magnetic polarity, arranged to hold immobile in rotation an opposite receiver wheel set, which is a reduced friction wheel including at the periphery thereof second stop elements, which are idle rollers or respectively magnets of the same polarity, cooperating in pairs with this holding surface on either side of a plane passing through the centres of the two wheel sets, the locking wheel set including a drive surface including an irregular relief portion or respectively an opposite magnetization and arranged to drive this receiver wheel set in jerks. A timepiece mechanism including such sequencer mechanism. A watch including such a timepiece mechanism and/or such a sequencer mechanism.

First claim

What is claimed is:

1. A sequencer mechanism comprising:
a locking wheel set driven in rotation about a first pivot axis, the locking wheel set comprising a peripheral holding surface of uniform magnetic polarity at a periphery of the locking wheel set,
the peripheral holding surface arranged to rotationally immobilize a receiver wheel set about a second pivot axis,
wherein said receiver wheel set includes a plurality of stop elements at a periphery of the receiver wheel set, the stop elements being magnets of a same polarity, and
wherein, in a locking stroke of said locking wheel set, two stop elements of the plurality of stop elements cooperate, through magnetization, with said peripheral holding surface on opposite sides of a plane passing through a center of said locking wheel set and a center of said receiver wheel set to rotationally immobilize the receiver wheel set,
wherein said locking wheel set further comprises a drive surface that includes an opposite polarity of the peripheral holding surface arranged to drive said receiver wheel set in a drive stroke of said locking wheel set, and
wherein said drive stroke occurs between two locking strokes.

2. The sequencer mechanism according to claim 1 ,
wherein the plurality of stop elements are at the periphery of the receiver wheel set and proximal to the periphery of the locking wheel set,
wherein the stop elements cooperate in pairs with said peripheral holding surface, such that at least one stop element of said pair cooperates through magnetization with said peripheral holding surface, on a median plane perpendicular to said first pivot axis, in a stop position in which said receiver wheel set is rotationally immobile and the stop elements cooperating with said peripheral holding surface, rest on either side of a main plane passing through the first pivot axis and through an intersection of the second pivot axis with said median plane, and
wherein said stop elements cooperate, by magnetic drive, with the drive surface to pivot said receiver wheel set,
wherein
said stop elements are receiver magnets, arranged in repulsion to a path magnetized with a first polarity, that forms said peripheral holding surface, and arranged to work in attraction with at least one path of second polarity, opposite to said first polarity, that forms said drive surface.

3. The sequencer mechanism according to claim 2 , wherein said receiver magnets, said magnetized path of the first polarity, and said at least one path of the second polarity, each have a magnetization oriented in said median plane.

4. The sequencer mechanism according to claim 1 , wherein, in a holding position, two of said stop elements cooperate with said peripheral holding surface on either side of said plane passing through the centers of said locking wheel set and of said receiver wheel set.

5. The sequencer mechanism according to claim 1 , wherein said locking wheel set is subjected to a drive torque which imparts a continuous rotation of said locking wheel set about said first pivot axis.

6. The sequencer mechanism according to claim 1 , wherein said receiver wheel set is subjected to a drive torque or resistant torque with respect to said second pivot axis.

7. The sequencer mechanism according to claim 1 , wherein said stop elements are all identical to each other.

8. The sequencer mechanism according to claim 1 , wherein said second pivot axis is parallel to said first pivot axis.

9. The sequencer mechanism according to claim 1 , wherein said peripheral holding surface is arranged to lock at least one of said stop elements by a magnetic force, over a restricted angular driving range of said locking wheel set, and
wherein said drive surface includes two elementary surfaces arranged to cooperate with two different stop elements of said stop elements to ensure pivoting of said receiver wheel set, each of said two different stop elements cooperating with a respective elementary surface over a portion of a step of the receiver wheel set.

10. The sequencer mechanism according to claim 1 , wherein the locking wheel set comprises at least two levels which together define an air gap between the at least two levels, and
wherein the periphery of the receiver wheel set is movable inside or in immediate proximity to the air gap.

11. The sequencer mechanism according to claim 1 , wherein said receiver wheel set comprises at least two levels, which together define an air gap between the at least two levels, and
wherein the periphery of the locking wheel set s movable inside or in immediate proximity to the air gap.

12. The sequencer mechanism according to claim 1 , wherein each of said stop elements is arranged to cooperate by magnetic drive with said drive surface, and
wherein each said stop element is a receiver magnet and is oriented with a first polarity directed towards the periphery of said locking wheel set, and
wherein areas of highest magnetic field density of each of said receiver magnets are equidistant from said second pivot axis.

13. The sequencer mechanism according to claim 12 , wherein said receiver magnets are equidistant from each other.

14. The sequencer mechanism according to claim 12 , wherein said drive surface further comprises a first attracting magnet oriented with a second polarity directed towards the periphery of said receiver wheel set, and
wherein said second polarity is opposite said first polarity.

15. The sequencer mechanism according to claim 12 , wherein said drive surface comprises a ferromagnetic portion in proximity to the periphery of said receiver wheel set.

16. The sequencer mechanism according to claim 12 , wherein said peripheral holding surface comprises a plurality of repelling magnets oriented with said first polarity directed towards the periphery of said receiver wheel set.

17. The sequencer mechanism according to claim 12 , wherein said receiver magnets, a magnetized path of the first polarity, and a path of the second polarity, have a magnetization oriented parallel to said first pivot axis.

18. A timepiece mechanism comprising at least one sequencer mechanism according to claim 12 , and a motor for driving said locking wheel set of said sequencer mechanism.

19. A timepiece mechanism comprising
at least one sequencer mechanism according to claim 1 , and
a motor for driving said locking wheel set of said sequencer mechanism.

20. The timepiece mechanism according to claim 19 , wherein said timepiece mechanism comprises a second motor subjecting said receiver wheel set of said sequencer mechanism to a torque about said second pivot axis to supply an additional torque during said drive stroke of said locking wheel set.

21. A watch including at least one sequencer mechanism according to claim 1 .

Assignees

• Montres Breguet Sa

Inventors

• Junod Benoit

Classifications

• G04B13/02 Primary

  Wheels; Pinions; Spindles; Pivots (bearings G04B31/00 {; chain wheels, spindles for chain wheels, also chains and driving weights G04B1/08}) · CPC title

• G04B13/003

  with a step for each complete revolution (counters in general H03K) · CPC title

• G04B13/002

  where rotation in one direction is changed into a stepping movement · CPC title

• G04C3/101 Primary

  constructional details · CPC title

• G04C5/005 Primary

  Magnetic or electromagnetic means · CPC title