EP2894522B1 - Optimised escapement with security system - Google Patents

Description

Field of the invention

The invention relates to a watch exhaust mechanism comprising a stop between a resonator and an escapement mobile subjected to a driving torque less than or equal to a nominal torque, said stop having at least one first actuator arranged to cooperate with said resonator and at least one second actuator arranged to cooperate with said mobile escape.

The invention also relates to a watch movement comprising at least one such escape mechanism.

The invention also relates to a timepiece comprising at least one such movement.

The invention relates to the field of watch mechanisms for the transmission of movement, and more particularly the field of escape mechanisms.

Background of the invention

An exhaust mechanism that includes at least a portion of its non-contact transmission is characterized by a better efficiency than an entirely mechanical exhaust.

However, it is sensitive to shocks and overloads that may be subject to the mobile escape.

The document US3183426A in the name of HAYDON describes different variants of magnetic escapement.

The document CH510285A in the name of FAR describes an anchor escapement with a magnet of predetermined polarity at its free end.

The document US3652955A in the name of CRUGER describes an oscillating device, comprising a mechanical element capable of periodic oscillation, and a means for applying electrical energy to maintain periodic oscillations of said mechanical element, and electrets for electrostatically coupling this mechanical element and these means of application of electrical energy.

The document EP2431823 in the name of BLANCPAIN SA describes a Swiss anchor whose rest surface of each pallet is a portion of a prism of elliptical section whose axis of symmetry coincides with the axis of pivoting of the anchor.

Summary of the invention

The present invention proposes to replace the mechanical contact force between a stopper and an escapement mobile by a force or a torque without contact of magnetic or electrostatic origin, with an arrangement that allows to ensure with certainty and in complete safety the second release function and jerky locking of the mobile exhaust, and which provides good protection against shocks and overbursts.

For this purpose, the invention relates to a clock escapement mechanism according to claim 1.

The invention also relates to a watch movement comprising at least one such escape mechanism, comprising energy storage means cooperating with said escape wheel.

The invention also relates to a timepiece, including a watch, comprising at least one such movement.

Brief description of the drawings

• la figure 1 représente, de façon schématisée et en coupe, un mécanisme d'échappement selon l'invention comportant des moyens d'arrêt à l'interface entre le résonateur et l'arrêtoir ;
• la figure 2 représente, de façon schématisée et en coupe, un mécanisme d'échappement selon l'invention comportant des moyens d'arrêt à l'interface entre l'arrêtoir et le mobile d'échappement ;
• la figure 3 est un schéma-blocs représentant une pièce d'horlogerie comportant un mouvement intégrant un mécanisme d'échappement selon l'invention.

Other features and advantages of the invention will appear on reading the detailed description which follows, with reference to the appended drawings, in which:

• the figure 1 shows schematically and in section, an exhaust mechanism according to the invention comprising stop means at the interface between the resonator and the stopper;
• the figure 2 shows schematically and in section, an exhaust mechanism according to the invention comprising stop means at the interface between the retainer and the escapement mobile;
• the figure 3 is a block diagram showing a timepiece comprising a movement incorporating an exhaust mechanism according to the invention.

Detailed Description of the Preferred Embodiments

The invention proposes to replace the usual mechanical contact force between a resonator, in particular a balance spring, and a stopper, and between a stopper and an escape wheel, in particular an escape wheel, by a contactless force. of magnetic or electrostatic origin.

The aim is to improve the efficiency of the exhaust, by the transmission of forces or torque using magnetic and / or electrostatic fields, and keeping all safety and operation in case of high torque at the escape wheel. (The exhaust does not pick up and does not hang).
In addition, the magnetic or electrostatic escapement makes it possible in many cases to have a constant force system.

The invention relates to a clockwork exhaust mechanism 1 comprising a retainer 3 between a resonator 2 and an escapement wheel 4.

This mobile escape is subjected to a driving torque less than or equal to a nominal torque.

The stopper 3 comprising at least one first actuator 31, which is arranged to cooperate with the resonator 2, and at least one second actuator 32, which is arranged to cooperate with the escape wheel 4.

According to the invention, the at least one first actuator 31 comprises at least a first magnetized or ferromagnetic polar mass 310, respectively electrified or electrostatically conductive, and the resonator 2 comprises at least a first magnetized or ferromagnetic track 21, respectively electrified or electrostatically conductive .

And at least the first polar mass 310 and / or the first track 21 creates a first magnetic or electrostatic field in a first air gap 210 between the at least one first pole mass 310 and the first track 21. This first field has an intensity that ensures relative drive of the retainer 3 and the resonator 2 as the torque applied to the mobile exhaust 4 is less than or equal to the nominal torque.

According to the invention, at least the stopper 3 comprises first stop means 211, 311 for limiting the relative movement between the at least one first actuator 31 and the resonator 2 when the torque applied to the escapement wheel 4 is greater than the nominal torque.

According to the invention, the stopper 3 and the resonator 2 comprise such first stop means 211, 311.

According to the invention, these first stop means 211, 311 comprise a magnetic or electrified barrier arranged to create a magnetic or electrostatic field greater than the first magnetic or electrostatic field.

In a particular variant, these first stop means 211, 311 comprise at least one mechanical stop.

More particularly, the at least one second actuator 32 comprises at least one second magnetized or ferromagnetic polar mass 320, respectively electrified or electrostatically conductive, and the escapement wheel 4 comprises at least one second magnetized or ferromagnetic track 42, respectively electrified or conductive electrostatically. At least the second polar mass 320 and / or the second track 42 creates a second magnetic or electrostatic field in a second air gap 420 between the at least one second polar mass 320 and the second track 42. This second field has an intensity ensuring the relative drive of the stop 3 and the mobile escape 4 as the torque applied to the mobile exhaust 4 is less than or equal to said nominal torque.

And the stopper 3 or / and the mobile escape 4 comprises second stop means 322; 422 to limit the relative movement between the at least one second actuator 32 and the mobile escape 4 when the torque applied to the mobile exhaust 4 is greater than the nominal torque.

When both the at least one first actuator 31 and the at least one second actuator 32 are thus equipped for a transmission without contact, the resonator 2, the stopper 3, the mobile escape 4, the first stop means 211, 311, and the second stop means 322, 422, together constitute a mechanical escapement substituting, when the torque is greater than the nominal torque, the non-contact escapement constituted by the resonator 2, the retainer 3, the mobile exhaust 4, the first polar mass 310 and the first track 21, the second polar mass 320 and the second track 42, which non-contact exhaust works when the torque applied to the mobile exhaust 4 is less than or equal to the nominal torque and without allowing the mechanical stop cooperation between the first stop means 211, 311, and / or the second stop means 322, 422, and the opposing surfaces of the resonator 2, or the stopper 3, or the mobile exhaust 4.

More particularly, the stopper 3 comprises first stop means 311 constituted by a set of horns, and the resonator 2 comprises first stop means 211 constituted by a tray pin arranged to cooperate with this set of horns.

More particularly, this set of horns is completed by a dart, and the tray pin is completed by a tray notch arranged to cooperate with this dart.

In a particular embodiment, this dart is a magnetic or electrified dart.

More particularly, the stopper 3 comprises second stop means 322 constituted by a set of pallets, and the escapement mobile 4 comprises second stop means 422 constituted by a toothing arranged to cooperate with this set of pallets.

In particular embodiments, the first track 21 comprises a magnetized layer of variable thickness, or respectively an electrified layer of variable thickness, or a magnetized layer of constant thickness but of variable magnetization, or respectively an electrified layer of constant thickness. but of variable electrification, or a variable surface density of micro-magnets, or respectively a variable surface density of electrets, or a ferromagnetic layer of variable thickness, or respectively an electrostatically conductive layer of variable thickness, or a layer ferromagnetic metal of variable form, or respectively an electrostatically conductive layer of variable shape, or a ferromagnetic layer with a variable surface density of holes, or respectively an electrostatically conductive layer with a variable surface density of holes.

In particular embodiments, the second track 42 comprises a magnetized layer of variable thickness, or respectively an electrified layer of variable thickness, or a magnetized layer of constant thickness but of variable magnetization, or respectively an electrified layer of constant thickness. but of variable electrification, or a variable surface density of micro-magnets, or respectively a variable surface density of electrets, or a ferromagnetic layer of variable thickness, or respectively an electrostatically conductive layer of variable thickness, or a layer ferromagnetic metal of variable form, or respectively an electrostatically conductive layer of variable shape, or a ferromagnetic layer with a variable surface density of holes, or respectively an electrostatically conductive layer with a variable surface density of holes.

In a particular embodiment, the stopper 3 is an anchor.

The invention also relates to a watch movement 100 comprising at least one such escapement mechanism 1, comprising energy storage means 5 cooperating with the escapement wheel 4.

The invention also relates to a timepiece 200, in particular a watch, comprising at least one such movement 100.

The figures are only an example, for example, the escape wheel can be modified so that it is two-level and the anchor at one level (except the stinger).

In sum, the invention realizes two escapements in one.

These two exhausts can be either mechanical, magnetic, electrostatic, or other.

These two exhausts are not in competition, but their operating ranges allow the second exhaust to take over when the first one leaves its permissible torque range.

If the torque is too high, the second exhaust avoids a stall, and does not block the system.

The "main" magnetic exhaust, for example, has a better performance because it operates without friction and is, for example, "constant force". it is still silent and has good chronometric properties. It may however present a safety problem, and stall in case of shock or over-torque at the mobile exhaust. The second complementary exhaust, of mechanical type in a particular variant, robust but of lower efficiency and hardly constant force, just takes over when the torque is extreme for the first exhaust. The two exhausts combined are therefore complementary and generally have better properties.

Claims (9)

1. Timepiece escapement mechanism (1) comprising a stop member (3) between a resonator (2) and an escape wheel set (4) subjected to a drive torque lower than or equal to a substantially non-zero nominal torque, said stop member (3) comprising at least a first actuator (31) arranged to cooperate with said resonator (2) and at least a second actuator (32) arranged to cooperate with said escape wheel set (4), characterized in that said at least one first actuator (31) comprises at least a first magnetically charged or ferromagnetic, or respectively electrically charged or electrostatically conductive pole piece (310), and in that said resonator (2) comprises at least one first magnetically charged or ferromagnetic, or respectively electrically charged or electrostatically conductive track (21), and at least said first pole piece (310) and/or said first track (21) creating a magnetic or electrostatic field in a first air gap (210) between said at least one first pole piece (310) and said first track (21), said first field having an intensity ensuring the relative driving of said stop member (3) and of said resonator (2) provided that the torque applied to said escape wheel set (4) is lower than or equal to said nominal torque, characterized in that said stop member (3) comprises first stop member arresting means (311), and in that said resonator (2) comprises first resonator arresting means (211), and characterized in that said first stop member arresting means (311) and said first resonator arresting means (211) comprise a magnetic or electrically charged barrier arranged to create a magnetic or electrostatic field higher than said first magnetic or electrostatic field beyond said first air gap (210), in order to limit the relative movement between said first actuator (31) and said resonator (2) when the torque applied to said escape wheel set (4) is greater than said nominal torque.
2. Escapement mechanism (1) according to claim 1, characterized in that said first stop member arresting means (311) and said first resonator arresting means (211) comprise at least one mechanical stop member.
3. Escapement mechanism (1) according to claim 1 or 2, characterized in that said at least one second actuator (32) comprises at least a second magnetically charged or ferromagnetic, or respectively electrically charged or electrostatically conductive pole piece (320), and in that said escape wheel set (4) comprises at least one second magnetically charged or ferromagnetic, or respectively electrically charged or electrostatically conductive track (42), and at least said second pole piece (320) and/or said second track (42) creating a second magnetic or electrostatic field in a second air gap (420) between said at least one second pole piece (320) and said second track (42), said second field having an intensity ensuring the relative driving of said stop member (3) and of said escape wheel set (4) provided the torque applied to said escape wheel set (4) is lower than or equal to said nominal torque, and further characterized in that said stop member (3) and/or said escape wheel set (4) comprises second arresting means (322; 422) for limiting the relative movement between said at least one second actuator (32) and said escape wheel set (4) when the torque applied to said escape wheel set (4) is greater than the nominal torque.
4. Escapement mechanism (1) according to claim 3, characterized in that said resonator (2), said stop member (3), said escape wheel set (4), said first pole piece (310) and said first track (21), said second pole piece (320) and said second track (42), said first arresting means (211; 311) and said second arresting means (322; 422) together form a first contactless escapement mechanism arranged to operate when the torque applied to said escape wheel set (4) is lower than or equal to said nominal torque, and without allowing mechanical banking cooperation between said first stop member arresting means (311) and said first resonator arresting means (211), and/or said second arresting means (322; 422) and the opposing surfaces of said resonator (2), or of said stop member (3), or of said escape wheel set (4).
5. Escapement mechanism (1) according to claim 3, characterized in that said resonator (2), said stop member (3) said escape wheel set (4), said first arresting means (211; 311) and said second arresting means (322; 422), together form a mechanical escapement arranged to replace, when the torque is greater than the nominal torque, the contactless escapement formed by said resonator (2), said stop member (3), said escape wheel set (4), said first pole piece (310) and said first track (21), said second pole piece (320) and said second track (42), which contactless escapement being arranged to operate when the torque applied to said escape wheel set (4) is lower than or equal to the nominal torque, and without allowing mechanical banking cooperation between said first stop member arresting means (311) and said first resonator arresting means (211), and/or said second arresting means (322, 422) and the opposing surfaces of said resonator (2), or of said stop member (3), or of said escape wheel set (4).
6. Escapement mechanism (1) according to claim 3, characterized in that said stop member (3) comprises second arresting means (322), formed by a set of pallet-stones, and in that said escape wheel set (4) comprises second arresting means (422), formed by a toothing arranged to cooperate with said set of pallet-stones.
7. Escapement mechanism (1) according to one of claims 1 to 6, characterized in that said stop member (3) is a pallet-lever.
8. Timepiece movement (100) including at least one escapement mechanism (1) according to one of claims 1 to 6.
9. Timepiece (200) including at least one movement (100) according to claim 8.

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