Timepiece assembly comprising a mechanical oscillator associated with a regulating device

Patent metadata

Field	Value
Publication number	US-10386791-B2
Application number	US-201715832909-A
Country	US
Kind code	B2
Filing date	Dec 6, 2017
Priority date	Dec 23, 2016
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

A mechanical movement timepiece assembly with a mechanical oscillator is formed by a resonator of the balance-hairspring type, and a device for regulating the oscillation frequency thereof using an auxiliary oscillator equipped with a quartz resonator. The regulating device includes a sensor, suitable for detecting the passage of the resonator via the neutral position thereof, a measuring device suitable for measuring, on the basis of position signals supplied by the sensor, a time drift of the mechanical oscillator relative to the auxiliary oscillator, and a device for applying to the resonator mechanical braking pulses when a certain time drift is observed. For this purpose, the resonator has a braking surface which extends over at least a certain sector having a certain length along the oscillation axis and against which a braking member may press in order to momentarily brake the resonator.

First claim

What is claimed is:

1. A timepiece assembly, comprising:
a mechanism;
a mechanical resonator that oscillates along an oscillation axis about a neutral position corresponding to a minimum potential mechanical energy state of the mechanical resonator;
a maintenance device that maintains the mechanical resonator, the maintenance device and the mechanical resonator together forming a mechanical oscillator that defines a working rate of the mechanism, each oscillation of the mechanical resonator exhibits two successive alternations between two end positions on the oscillation axis which define the oscillation amplitude of the mechanical oscillator;
a regulating device that regulates a frequency of oscillation of the mechanical oscillator, the regulating device comprising an auxiliary oscillator, a regulation pulse application device that applies regulation pulses to the mechanical resonator, and an electronic control circuit that generates a control signal which is supplied to and activates the regulation pulse application device; and
a sensor that detects a position of the mechanical resonator on the oscillation axis;
wherein the regulating device comprises a measuring device that measures, on the basis of position signals supplied by said sensor, a time drift of the mechanical oscillator relative to the auxiliary oscillator,
wherein the regulation pulse application device is formed by an electromechanical device that generates, in response to the control signal which is dependent on the time drift measured, mechanical braking pulses applied to a braking surface of the mechanical resonator,
wherein at least one mechanical braking pulse applies a brake force on the braking surface when a time drift of the mechanical oscillator is detected, and
wherein the braking surface includes a portion that extends along said oscillation axis and enables the application of the mechanical braking pulse during an alternation of the mechanical oscillator in an amplitude range corresponding to a usable operating range of the mechanical oscillator, and
wherein said application of the mechanical braking pulse is applied at a selected time such that said mechanical braking pulse does not occur while the mechanical resonator passes the neutral position.

2. The timepiece assembly according to claim 1 , wherein the regulation pulse application device includes an actuator comprising a braking member that actuates, in response to the control signal, to apply a mechanical force to an oscillating member of the mechanical resonator during the mechanical braking pulses, and
wherein the oscillating member of the mechanical resonator defines the braking surface.

3. The timepiece assembly according to claim 2 , wherein the regulation pulse application device is arranged such that braking energy of each mechanical braking pulse is less than a locking energy, so as not to stop the mechanical resonator momentarily during the mechanical braking pulses, and
wherein the oscillating member and the braking member are arranged such that the mechanical braking pulses are applied by dynamic dry friction between the braking member and the braking surface of the oscillating member.

4. The timepiece assembly according to claim 3 , wherein said actuator actuates said braking member via a piezoelectric element or via an electromagnetic system.

5. The timepiece assembly according to claim 4 , wherein said actuator comprises a timepiece motor, the braking member being mounted on a rotor of the timepiece motor,
wherein the braking member applies pressure on the oscillating member when the rotor performs a rotation, and
wherein the rotation is induced by a power supply of a motor coil in response to said control signal.

6. The timepiece assembly according to claim 3 , wherein the oscillating member is formed by a pivoting balance comprising a felloe which defines said braking surface,
wherein the braking surface is substantially circular, and
wherein the braking member comprises a movable part which defines a braking pad and which applies pressure against the circular braking surface during the application of the mechanical braking pulses.

7. The timepiece assembly according to claim 3 , wherein the oscillating member is includes a pivoting balance comprising a central shaft which bears a part, other than the felloe of the balance, which defines said braking surface,
wherein said braking surface is substantially circular; and
wherein the braking member comprises a movable part which defines a braking pad and which applies pressure against the circular braking surface during the application of the mechanical braking pulses.

8. The timepiece assembly according to claim 6 , wherein said movable part is a first part and said braking pad is a first brake pad,
wherein said braking member or another braking member also forming said actuator comprises at least a second movable part which defines a second brake pad,
wherein said actuator is arranged such that, during the application of said mechanical braking pulses, the first and second brake pads apply two radial forces to the balance, and
wherein the two radial forces are diametrically opposed relative to the axis of rotation of the balance.

9. The timepiece assembly according to claim 7 , wherein said movable part is a first part and said braking pad is a first brake pad,
wherein said braking member or another braking member also forming said actuator comprises at least a second movable part which defines a second brake pad,
wherein said actuator is arranged such that, during the application of said mechanical braking pulses, the first and second brake pads apply two radial forces to the balance, and
wherein the two radial forces are diametrically opposed relative to the axis of rotation of the balance.

10. The timepiece assembly according to claim 6 , wherein said movable part is a first part and said braking pad is a first brake pad,
wherein said braking member or another braking member also forming said actuator comprises at least a second movable part which defines a second brake pad, and
wherein said actuator is arranged such that, during the application of said braking pulses, the first and second brake pads apply to the balance two substantially axial forces of opposite directions.

11. The timepiece assembly according to claim 7 , wherein said movable part is a first part and said braking pad is a first brake pad,
wherein said braking member or another braking member also forming said actuator comprises at least a second movable part which defines a second brake pad, and
wherein said actuator is arranged such that, during the application of said braking pulses, the first and second brake pads apply to the balance two substantially axial forces of opposite directions.

12. The timepiece assembly according to claim 1 , wherein each oscillation period of the mechanical oscillator has a first alternation followed by a second alternation,
each first alternation and each second alternation having a passage of the mechanical resonator via the neutral position of the mechanical resonator at a median time and a duration between an initial time and an end time defined respectively by the two end positions occupied by the mechanical resonator at the start of and at the end of each alternation, respectively;
wherein said measuring device determines whether the time drift of the mechanical oscillator corresponds an advance or to a delay,
wherein said control circuit and said regulation pulse application device selectively apply a first mechanical braking pulse to the mechanical resonator, when the time drift measured corresponds to said at least a certain

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Tombez Lionel
• Haemmerli Alexandre

Classifications

• G04C3/04

  wherein movement is regulated by a balance · CPC title

• G04C9/04 Primary

  by blocking the driving means · CPC title

• G04B18/04

  Adjusting the beat of the pendulum, balance, or the like, e.g. putting into beat · CPC title

• G04B15/14

  Component parts or constructional details, e.g. construction of the lever or the escape wheel {(assembly and manufacture of the spring G04B1/145; assembly and manufacture of components, e.g. pinions, spindles G04B13/02; lubrication of clockwork bearings G04B31/008; oils for clockwork bearings in general G04B31/08)} · CPC title

• G04C9/08

  by electric drive · CPC title