Regulating element for wristwatch and mechanical movement comprising one such regulating element

1. Regulating member for mechanical wristwatch, having:

a balance,

a return member for returning said balance towards at least one position of equilibrium,

a driving element for maintaining the balance's movement around said position of equilibrium,

wherein said balance is linked to at least one mobile permanent magnet,

and wherein said return member has at least one fixed permanent magnet for generating a magnetic field in order to return said balance towards said position of equilibrium.

2. The regulating member of claim 1 , wherein said balance has a rotation axle, said at least one mobile permanent magnet oscillating along a circular trajectory around said rotation axle.

3. The regulating member of claim 1 , wherein said fixed magnets are distributed on an arc of circle.

4. The regulating member of claim 3 , wherein at least one said mobile magnet oscillates along a circular trajectory between two fixed magnets spaced angularly by less than 180° on said arc of circle.

5. The regulating member of claim 1 , wherein said movement of the balance is constituted by oscillations around the balance's rotation axle, the amplitude of said oscillations being less than 180°.

6. The regulating member of claim 1 , wherein said movement of the balance is constituted by oscillations around the balance's rotation axle, the amplitude of said oscillations being greater than 180° and preferably less than 300°.

7. The regulating member of claim 1 , wherein said driving element is constituted by an escapement to transmit the circular oscillations from the balance to the rest of the movement.

8. The regulating member of claim 1 , wherein said return member acts on said balance without matter deformation.

9. The regulating member of claim 1 , wherein said return member acts without contact with said balance.

10. The regulating member of claim 1 , wherein said magnetic field is constant in time.

11. The regulating member of claim 1 , wherein at least one said fixed magnet is placed so as to push back at least one said mobile magnet towards said position of equilibrium.

12. The regulating member of claim 1 , wherein the magnetic interaction between said at least one fixed magnet and said at least one mobile magnet is minimal at said position of equilibrium.

13. The regulating member of claim 1 , wherein said position of equilibrium is determined by the action of at least two fixed magnets acting on at least one same mobile magnet.

14. The regulating member of claim 13 , wherein, at the position of equilibrium, the magnetic fields exerted by the two said fixed magnets onto said at least one same mobile magnet are of equal intensity.

15. The regulating member of claim 13 , wherein said mobile magnet is at equidistance between two fixed magnets at said position of equilibrium.

16. The regulating member of claim 1 , wherein said position of equilibrium is determined by the action of at least one fixed magnet acting simultaneously on at least two mobile magnets.

17. The regulating member of claim 1 , wherein said position of equilibrium is a stable position of equilibrium in which the magnetic attraction between the fixed magnets and the mobile magnets is minimal.

18. The regulating member of claim 1 , having the same number of mobile magnets as fixed magnets.

19. The regulating member of claim 1 , wherein, at the position of equilibrium:

each fixed magnet exerts a magnetic field of equal intensity on two mobile magnets,

and each mobile magnet exerts a magnetic field of equal intensity on two fixed magnets.

20. The regulating member of claim 1 , wherein said mobile magnet or magnets are fixed relative to said balance.

21. The regulating member of claim 20 , wherein said balance is symmetrical relative to said rotation axle.

22. The regulating member of claim 20 , wherein said mobile magnets are placed in symmetric fashion around said rotation axle.

23. The regulating member of claim 1 , having mechanical and/or magnetic stops to limit the amplitude of possible rotations of said balance.

24. The regulating member of claim 1 , wherein said balance is constituted by a mobile permanent magnet.

25. The regulating member of claim 1 , wherein said at least one mobile permanent magnet is linked to the pallets that thus also constitute the balance.

26. The regulating member of claim 1 , wherein said at least one mobile permanent magnet is mounted in the plane of the balance and wherein said at least one fixed permanent magnet is mounted in a plane parallel to said balance.

27. The regulating member of claim 26 , wherein said at least one fixed permanent magnet and said at least one mobile permanent magnet are each constituted by a disc having sectors of alternating polarities.

28. The regulating member of claim 1 , having means for compensating the variation of magnetic field linked to the temperature.

29. The regulating member of claim 1 , wherein said driving element is constituted by a mechanical escapement, for example a Swiss pallets escapement.

30. The regulating member of claim 1 , wherein said escapement is a magnetic escapement.

31. The regulating member of claim 1 , said balance being held by at least one magnetic bearing.

32. The regulating member of claim 1 , the position of said at least one magnet being adjustable for regulating the frequency of the oscillations of said balance.

33. The regulating member of claim 1 , at least one said magnet acting on an electronic system to correct or determine the frequency of oscillation of said balance.

34. The regulating member of claim 33 , said electronic system having at least one Hall sensor or a magnetoresistive sensor subjected to the action of the magnetic field of one of the magnets to generate a measuring signal depending on the oscillations of said balance.

35. The regulating member of claim 33 , said electronic system having at least one coil subjected to the action of the magnetic field of one of the mobile magnets to generate a signal depending on the oscillations of said balance.

36. The regulating member of claim 33 , having at least one electronic circuit powered by the electro-motor force generated by the displacement of one of said magnets in the proximity of a coil.

37. The regulating member of claim 1 , having east least one bridge made of a non-magnetic material.

38. The regulating member of claim 1 , having a magnetic screen in order to protect external elements from the magnetic field generated by said permanent magnets.

39. The regulating member of claim 1 , wherein the displacements of said balance are constrained by a guiding surface.

40. The regulating member of claim 1 , wherein the return force of said balance varies linearly with the angular position of the balance.

41. The regulating member of claim 1 , wherein said balance moves along a circular trajectory,

the volume of the fixed and/or mobile magnets and/or their magnetization varying in continuous manner along said trajectory.

42. The regulating member of claim 41 , wherein said balance oscillates around a position of equilibrium along a circular trajectory,

the magnetic interaction between said fixed permanent magnets and said mobile permanent magnets increases when the balance moves away from said position of equilibrium along said trajectory, so as to achieve an increasing return force.

43. The regulating member of claim 1 , wherein at least one of said fixed and/or mobile permanent magnets is magnetized in non-homogenous manner.

44. The regulating member of claim 1 , wherein said balance is constituted of several oscillating elements connected by a cinematic chain and oscillating with variable frequencies.

45. Mechanical movement for wristwatch having a regulating member according to claim 1 .

46. Movement according to claim 45 , wherein the cinematic chain between said regulating member and the display elements has at least one belt of non-magnetic material.

47. Movement according to claim 45 , wherein at least one portion of said balance is visible from outside the movement.

48. Regulating member for mechanical wristwatch, having:

a balance,

a return member for returning said balance towards at least one position of equilibrium,

a driving element for moving the balance away from said position of equilibrium,

said balance being associated with at least one mobile permanent magnet,

said return member comprising one or several fixed permanent magnet collaborating with said mobile permanent magnet.

49. Regulating member for mechanical wristwatch, having a balance with at least one mobile magnet cooperating with at least one fixed magnet for returning said balance towards at least one position of equilibrium,

said at least one mobile magnet and said at least one fixed magnet being arranged so that the attraction force of said balance is linearly proportional to a distance between said mobile magnet and said fixed magnet.