High quality factor resonator for mechanical watches

Patent metadata

Field	Value
Publication number	US-10152025-B2
Application number	US-201715715728-A
Country	US
Kind code	B2
Filing date	Sep 26, 2017
Priority date	Oct 18, 2016
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

Movement including an escapement mechanism and a resonator including an inertial element subjected to the action of a flexible gimbal and cooperating with an escape wheel set pivoting about a main axis, which includes driving means cooperating in a continuous transmission of motion with complementary means of the inertial element in every angular position of the latter, the flexible gimbal tending to return these complementary means towards the main axis, and including elastic return means about axes orthogonal to the main axis and restricting the mobility of the inertial element in two rotational degrees of freedom, about a fixed position of the centre of inertia of the inertial element with respect to a plate.

First claim

What is claimed is:

1. A timepiece movement for a mechanical watch, comprising, arranged on a plate, a resonator mechanism and an escapement mechanism subjected to the torque of driving means comprised in said movement, said resonator mechanism including an inertial element arranged to oscillate with respect to said plate, said inertial element being subjected to the action of elastic return means directly or indirectly fixed to said plate, and said inertial element being arranged to cooperate with an escape wheel set comprised in said escapement mechanism and which pivots about a main axis, wherein said escape wheel set includes driving means arranged to cooperate in a continuous transmission of motion with complementary continuous driving means comprised in said inertial element in every angular position of the latter, and in that said elastic return means are arranged to tend to return said complementary continuous driving means towards said main axis, and in that said elastic return means include first elastic return means about a first axis and arranged to tend to return said complementary continuous driving means towards said main axis, and second elastic return means about a second axis and arranged to tend to return said complementary continuous driving means towards said main axis, said first axis and said second axis being perpendicular to each other and to said main axis, and in that said elastic return means form gimbal type guiding means and are arranged to prohibit the movement of the centre of inertia of said inertial element in the three linear degrees of freedom and in one rotational degree of freedom, so as to allow said inertial element mobility in only two rotational degrees of freedom, about said first axis and said second axis and about a central point forming a fixed position of said centre of inertia with respect to said plate.

2. A movement according to claim 1 , wherein said main axis, said first axis and said second axis are concurrent.

3. The movement according to claim 1 , wherein said first elastic return means and said second elastic return means are arranged in series, said first elastic return means being arranged between said plate and an intermediate crosspiece, and said second elastic return means being arranged between said intermediate crosspiece and said inertial element, or vice versa.

4. The movement according to claim 1 , wherein said first elastic return means, on the one hand, and said second elastic return means on the other, are arranged to apply a return torque proportional to the angle of rotation imparted thereto.

5. The movement according to claim 1 , wherein said inertial element has, with respect to the frame of reference formed by said main axis, said first axis and said second axis, a diagonal inertia matrix, whose terms are equal along at least two of said main axis, said first axis and said second axis.

6. The movement according to claim 2 , wherein said inertial element has, with respect to the frame of reference formed by said main axis, said first axis and said second axis, a diagonal inertia matrix, whose terms are equal along at least two of said main axis, said first axis and said second axis, and wherein said inertial element has, with respect to the frame of reference formed by said main axis, said first axis and said second axis, a diagonal inertia matrix, whose terms are equal along said main axis and said first axis.

7. The movement according to claim 1 , wherein said driving means include a substantially radial slot relative to said main axis and which cooperates with a finger comprised in said complementary continuous driving means.

8. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means are formed by rotating flexible guiding means devoid of pivots.

9. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means together form a monolithic component.

10. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means with two strips, which are either crossed on the same level, or strips located in two close parallel levels and whose projections onto a plane parallel to said levels intersect.

11. The movement according to claim 1 , wherein, in a said rotating flexible bearing with two strips, the real or projected point of intersection of the two strips is located at a point situated between 0.12 and 0.14 times the length of said strips, and said two strips form between them an angle comprised between 60 and 80 degrees.

12. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means of the RCC pivot type arranged head-to-tail.

13. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means are double to increase the stiffness of the flexible gimbal in the degrees of freedom that must be related.

14. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means with flexible strips, wherein said strips are made of elinvar.

15. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means with flexible strips, wherein said strips are made of oxidized silicon to compensate for the effects of temperature variations.

16. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means with two strips, which are strips located in two close parallel levels and whose projections onto a plane parallel to said levels intersect, each said strip belonging to a monolithic module comprising said strip and the means of attachment thereof, and said flexible bearing with two strips comprising two said modules assembled back-to-back.

17. The movement according to claim 1 , wherein a first oscillation period, a function of a first inertia and of a first elastic constant of the bearing in a first rotation about said first axis, is equal to a second first oscillation period, a function of a second inertia and of a second elastic constant of the bearing in a second rotation about said second axis.

18. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means have identical features.

19. The movement according to claim 1 , wherein the plane defined by said first axis and said second axis, in equilibrium, is perpendicular to the plane of said plate, and in that said main axis is parallel to the plane of said plate.

20. The movement according to claim 1 , wherein the plane defined by said first axis and said second axis, in equilibrium, is parallel to the plane of said plate, and in that said main axis is perpendicular to the plane of said plate.

21. The movement according to claim 1 , wherein said driving means include a hole arranged to guide a roller arranged to roll on an annular track comprised in said inertial element, which forms said complementary continuous driving means.

22. The movement according to claim 1 , wherein said first elastic return means and/or said second elastic return means include rotating flexible guiding means with crossed strips and are protected

Assignees

• Eta Sa Mft Horlogere Suisse
• Eta Sa Mft Horlogere Suisse

Inventors

• Winkler Pascal
• Di Domenico Gianni
• Helfer Jean-Luc

Classifications

• G04B17/063

  Balance construction (balances with frequency adjustment screw G04B18/006; balances with temperature compensation G04B17/222; balancing devices G04B17/28) · CPC title

• G04B17/06

  Oscillators with hairsprings, e.g. balance {(electrically driven balances G04C3/04; contacts actuated by a balance G04C13/065)} · CPC title

• G04B17/04 Primary

  Oscillators acting by spring tension · CPC title

• G04B17/045 Primary

  with oscillating blade springs (mechanical oscillations maintained by electro-magnetic means, e.g. tuning forks G04C3/10) · CPC title

• G04B15/02 Primary

  permanently in contact with the regulating mechanism · CPC title