CH719973A2 - Clockwork regulating body with spiral spring fitted with pressure compensation means. - Google Patents

Abstract

The invention relates to a regulating member (1) for a watch movement comprising an oscillating mass, for example a balance wheel, a spiral spring comprising a flexible ribbon (2) wound on itself in several turns, the ribbon (2) having a predefined rigidity to allow the oscillating mass to perform a rotary oscillatory movement, the ribbon (2) comprising an external end (9), the regulating member (1) comprising an elastic pressure compensation device (50) external, connecting the external end (9) to a first immobile support (7) relative to the clockwork movement, the elastic compensation device (50) being configured to adapt its stiffness as a function of the external pressure in order to compensate for the effect of external pressure on the regulating organ (1). The invention also relates to a watch movement comprising such a regulating member (1).

Description

Technical field of the invention

[0001] The invention relates to a spiral spring regulating member provided with pressure compensation means. The invention also relates to a clock movement comprising such a regulating member.

Technology background

[0002] Most current mechanical watches are equipped with a sprung balance and a Swiss anchor escapement mechanism. The sprung balance constitutes the time base of the watch. It is also called a resonator or regulating organ.

[0003] The exhaust, for its part, fulfills two main functions: – maintain the comings and goings of the resonator; – count these comings and goings.

[0004] To constitute a regulating organ, you need an inertial element, guidance and an elastic return element. Traditionally, a spiral spring plays the role of an elastic return element for the inertial element that constitutes a balance wheel. This balance wheel is guided in rotation by pivots, which generally rotate in plain ruby bearings.

[0005] A frequency is chosen for the mechanical resonator, which is determined to obtain a predefined rate for the clock movement.

However, during its operation, such a mechanical resonator may be subject to disturbances caused by changes in external parameters, which generate variations in frequency of the resonator. These parameters are for example temperature, pressure, humidity, or gravity. The variation in frequency of the resonator results in an error in the measurement of time and therefore in the running of the clock movement.

[0007] For example, document CH 704687 describes a regulating member comprising a spiral spring and a member for correcting the position of the eyebolt to correct deformations of the spiral spring due to temperature.

[0008] Today, there is no regulating organ provided with compensation means configured to compensate for variations in ambient pressure. Thus, when the pressure changes, for example because of altitude, the regulating member loses precision, because the pressure difference modifies the aerodynamic friction of the regulating member. For example, an increase in pressure causes a reduction in the oscillation frequency of the regulating organ.

Summary of the invention

[0009] The aim of the present invention is to overcome all or part of the drawbacks cited above by proposing a watchmaking regulating member with a spiral spring provided with pressure compensation means, which are precise and adapted to a spiral spring. .

[0010] For this purpose, the invention relates to a regulating member for a watch movement comprising an oscillating mass, for example a balance wheel, a spiral spring comprising a flexible ribbon wound on itself in several turns, the ribbon having a predefined rigidity to allow the oscillating mass to perform a rotary oscillatory movement, the ribbon comprising an external end.

[0011] The invention is remarkable in that the regulating member comprises an elastic device for compensating for the external pressure, connecting the external end of the ribbon to a first support which is immobile relative to the clockwork movement, the elastic device for compensation being configured to adapt its stiffness as a function of the external pressure in order to compensate for the effect of the external pressure on the regulating member.

[0012] Thanks to the invention, the prestressing means exert a variable force or torque on the elastic element of the elastic compensation device as a function of the pressure, so that the regulating member substantially maintains a precise course despite significant changes in pressure. Indeed, when the pressure changes, the prestressing means modify the force or the torque exerted on the elastic element, so that the stiffness of the assembly comprising the elastic element and the spiral spring is modified. By modifying the stiffness of this assembly, we adjust the operation of the regulating organ. Consequently, when the pressure changes, the elastic device is mechanically impacted to adjust the action of the spiral spring to this change.

[0013] This elastic element modifies the rigidity of the attachment point and provides additional flexibility to the resonator. Thus, the effective stiffness of the resonator includes the stiffness of the ribbon and the stiffness of the elastic element. The variable force or torque allows the elastic element to be pre-stressed, preferably without pre-stressing the tape and without moving the end of the tape. By pre-stressing the elastic element, its rigidity changes, while the rigidity of the ribbon remains unchanged, since it is not pre-stressed and its end does not move.

By modifying the flexibility of the elastic element, the rigidity of the resonator (rigidity of the ribbon and rigidity of the elastic element) changes, which consequently modifies the operation of the resonator. The elastic element being preferably more rigid than the ribbon, the share of the flexibility of the elastic element in the overall flexibility is less than that of the ribbon. Consequently, a modification of the rigidity of the elastic element modifies the rigidity of the entire resonator, and consequently fine-tunes its operation, which makes it possible to precisely adjust the frequency of our time base. We thus obtain great precision in maintaining walking depending on the pressure.

[0015] According to a particular embodiment of the invention, the elastic compensation device comprises an elastic element arranged between the outer end of the ribbon and the immobile support, as well as prestressing means for applying a variable force or torque on the elastic element as a function of the external pressure.

[0016] According to a particular embodiment of the invention, the prestressing means comprise a spring part connected to the elastic element, the spring part transmitting the force or the torque to the elastic element.

[0017] According to a particular embodiment of the invention, the prestressing means comprise an aneroid capsule whose volume varies as a function of the external pressure, so as to transmit a variable force or torque as a function of the external pressure.

[0018] According to a particular embodiment of the invention, the aneroid capsule comprises a movable wall and a stationary wall connected by at least one spring.

According to a particular embodiment of the invention, the spring part comprises a first flexible blade connected to the elastic element.

According to a particular embodiment of the invention, the spring part comprises a translation table connected to the first flexible blade, the aneroid capsule being in contact with the translation table.

[0021] According to a particular embodiment of the invention, the elastic part comprises a first movable element connected to the first flexible blade, and a second movable element, the first movable element and the second movable element being connected by a pair of parallel flexible blades.

According to a particular embodiment of the invention, the spring part comprises a second flexible blade connecting the second movable element to the aneroid capsule.

According to a particular embodiment of the invention, the elastic element comprises a suspended point body and a pair of uncrossed blades connecting the suspended point body to the first immobile support.

[0024] According to a particular embodiment of the invention, the prestressing means are connected to the suspended point body to exert the force or torque on the suspended point body.

[0025] According to a particular embodiment of the invention, the regulating member comprises means for adjusting the prestressing means to apply a variable force on the prestressing means, for example on the first elongated movable element.

[0026] According to a particular embodiment of the invention, the regulating member extends substantially in the same plane, except for the oscillating mass.

The invention also relates to a watch movement comprising such a regulating member.

Brief description of the figures

[0028] The aims, advantages and characteristics of the present invention will appear on reading several embodiments given solely by way of non-limiting examples, with reference to the appended drawings in which: – Figure 1 schematically represents a sectional view from above of a first embodiment of a regulating member provided with pressure compensation means, and - Figure 2 schematically represents a top sectional view of a second embodiment of a regulating member provided with means of pressure compensation.

Detailed description of the invention

[0029] Figures 1 and 2 each represent an embodiment of a regulating member 1.10 according to the invention, the regulating member 1.10 comprising an elastic device 50 configured to compensate for a variation in pressure exerted on the regulating member 1, 10. Such regulating members 1, 10 are intended to be arranged in a clockwork movement to regulate it.

In these embodiments, the regulating member 1.10 comprises a spiral spring provided with a flexible ribbon 2 wound on itself in several turns. The flexible ribbon 2 comprises an external end 9 and an internal end 8.

The regulating member 1, 10 comprises an oscillating mass, for example an annular balance, not shown in the figures, which is connected to the internal end 8 of the ribbon 2, the ribbon 2 having a predefined rigidity to allow the oscillating mass to perform a rotary oscillatory movement. For example, the oscillating mass comprises an axial rotation shaft, the internal end 8 of the ribbon 2 being connected to said shaft.

Preferably, the regulating member 1, 10 extends substantially in the same plane, except for the oscillating mass, which oscillates in a parallel plane, above the spiral spring.

[0033] According to the invention, the regulating member 1, 10 comprises an elastic device 50 for compensating an external parameter configured to adapt the stiffness of the elastic element 5 as a function of the pressure in order to compensate for the effect of the pressure on the regulating organ 1, 10.

The elastic compensation device 50 is configured to adapt its stiffness as a function of variations in the surrounding pressure in order to compensate for the effect of these variations on the spiral spring. The elastic compensation device 50 preferably has a stiffness greater than the ribbon 2.

The elastic device 50 comprises an elastic element 5 connecting the outer end 9 of the ribbon 2 to a stationary support 7 relative to the clock movement, for example to a fixed plate. The elastic device 50 further comprises prestressing means 6 for applying a variable force or torque to the elastic element 5 as a function of the external parameter.

The elastic element 5 here comprises a suspended point body 3 and a pair of uncrossed blades 4 connecting the suspended point body 3 to the immobile support 7. The suspended point body 3 is for example a cylindrical body of height substantially equal to the diameter , the uncrossed blades 4 moving away from the suspended point body 3 to the immobile support 7.

The elastic element 5 is arranged in the extension of the flexible ribbon 2, the spiral spring and the elastic element 5 being adjacent, but avoiding contact during the oscillation of the oscillating mass.

The prestressing means 6 are configured to exert the force or torque on the suspended point body 3. Thus, the stiffness of the elastic element is modified, because the prestressing means 6 modify the stiffness of the uncrossed blades 4.

The prestressing means 6 comprise a spring part provided with a single flexible blade 11 connected to the suspended point body 3. The single flexible blade 11 extends in the axis of the elastic element, tangentially to the spiral spring , and is slightly offset relative to the external end 9.

The spring part is further configured to undergo a variable force or torque, which is transmitted to the elastic element 5.

[0041] In the first embodiment of Figure 1, the spring part of the prestressing means 6 comprises a translation table 33 provided with a first mobile element 12 in the shape of an L and a second immobile support 18 relative to At the move. The first movable element 12 is connected to the single flexible blade 11 by one end of a first arm of the L. The second arm of the L includes a rounded projection 53 on the external side. The translation table 33 comprises two substantially parallel flexible blades 14 connecting the first movable element 12 to the second immobile support 18.

[0042] To transmit a variable force or torque as a function of the external pressure to the spring part, the prestressing means 6 comprise an aneroid capsule.

Such a capsule is generally used to measure atmospheric pressure. To this end, the capsule comprises a space at least partly empty of air, and comprises a spring-type elastic return element in the space to retain a movable wall of the capsule. Thus, when the external pressure increases, the capsule is compressed, and when the external pressure decreases, the capsule expands.

[0044] In Figure 1, the aneroid capsule comprises a variable volume depending on the external pressure.

[0045] For this, the aneroid capsule comprises a movable wall 13 and a stationary wall 15. A sealed enclosure, not shown in the figures, makes it possible to create at least a partial vacuum inside the movable and stationary walls 13. 15.

The immobile wall 15 is immobile with respect to the movement, and is for example integral with a plate or a fixed plate bridge. The immobile wall 15 here has a schematic parallelepiped shape.

The movable wall 13 also has a schematic parallelepiped shape, the movable wall 13 being arranged opposite the immobile wall 15.

The aneroid capsule further comprises a spring 16 connecting the movable 13 and immobile 15 walls, which form the elastic return element of the aneroid capsule. The spring 16 is arranged between the movable 13 and stationary 15 walls.

[0049] Depending on the pressure exerted on the movable wall 13, the spring 16 extends, particularly when the pressure drops, or contracts, particularly when the pressure increases. Thus, it brings the movable wall 13 closer to or further from the immobile wall 15.

The spring part of the prestressing means 6 is connected to the aneroid capsule, the spring part transmitting the force or torque of the aneroid capsule to the point body 3 of the elastic element 5.

The function of the translation table 33 is to transform the spacing distance of the capsule into a constraint force for the point body 3.

[0052] When the pressure changes, the movable wall 13 approaches or moves away from the stationary wall 15. Thus, the movable element 12 of the translation table 33 experiences a more or less significant thrust force towards the element. elastic 5, this force being transmitted to the point body 3 via the single flexible blade 11.

[0053] The prestressing means 6 exert a variable thrust force on the elastic element 5. Consequently, the stiffness of the elastic element 5 varies, and makes it possible to adapt the operation of the balance to the external pressure conditions to keep the precision of the regulating organ.

[0054] For example, when the pressure increases, the movable wall 13 approaches the stationary wall 15. This rapprochement causes a reduction in the thrust force on the point body 3, which is exerted by the prestressing means 6. Thus , the stiffness of the elastic element 5, is increased.

On the contrary, when the pressure decreases, the movable wall 13 moves away from the stationary wall 15. This separation generates an increase in the thrust force on the point body 3, which is exerted by the prestressing means 6. Thus, the stiffness of the elastic element 5 is reduced.

[0056] In the second embodiment, the regulating member 10 comprises a spiral spring, an oscillating mass (not shown in the figure), an elastic element 5, and a first flexible blade 11 identical to the first embodiment.

[0057] To exert the force or torque on the elastic element 5, the spring portion of the prestressing means 6 comprises a first elongated movable element 22, connected to the flexible blade 11 and arranged in its extension.

The spring part comprises a first pair of parallel flexible blades 25 arranged on the same side, and connects the first movable element 22 to a second movable element 28.

The second movable element 28 is connected laterally to an aneroid capsule 15 by a second flexible blade 21 substantially parallel to the first movable element 22 in the rest position of the regulating member 10.

[0060] A second pair of parallel flexible blades 26 connects the second movable element 28 to a third stationary element 27 relative to the watch movement. The second pair of parallel flexible blades 26 and the third stationary element 27 being arranged in series with the second pair of parallel flexible blades 25 and the second movable element 28. The third stationary element 27 is for example integral with a fixed plate.

[0061] Adjustment means, such as a screw, can be added to exert a force 59 on the first movable element 22. By increasing the force 59, the movement of the aneroid capsule is transmitted more weakly to the first movable element 22, while that by reducing the force, the movement of the aneroid capsule is transmitted more strongly to the first movable element 22. The adjustment means make it possible to adjust the sensitivity of the prestressing means 6 to pressure.

[0062] Thus, when the movable wall 13 moves away from or approaches the stationary wall 15, the second flexible blade 21 transmits a movement to the second movable element 28, which transmits it to the first movable element 22 by the second pair of blades parallel flexibles 25. The first movable element 22 is guided by the first translation table 33 to transmit the force or torque to the elastic element 5 through the first flexible blade 11.

[0063] Similar to the first embodiment, the variation in pressure will cause a variation in volume of the aneroid capsule 15, and therefore a modification of the stiffness of the elastic element 5 and the operation of the regulating member. 10.

[0064] The invention also relates to a clock movement, not shown in the figures, the movement comprising a rotary regulating member 1, 10 as described above.

Naturally, the invention is not limited to the embodiments described with reference to the figures and variants could be considered without departing from the scope of the invention.

Claims (14)

1. Regulating member (1, 10) for a watch movement comprising an oscillating mass (19), for example a balance wheel, a spiral spring comprising a flexible ribbon (2) wound on itself in several turns, the ribbon ( 2) having a predefined rigidity to allow the oscillating mass to perform a rotary oscillatory movement, the ribbon (2) comprising an external end (9), characterized in that the regulating member (1, 10) comprises an elastic device compensation (50) for the external pressure, connecting the external end (9) of the ribbon (2) to a first immobile support (7) relative to the clockwork movement, the elastic compensation device (50) being configured to adapt its stiffness as a function of the external pressure in order to compensate for the effect of the external pressure on the regulating member (1, 10). 2. Regulating member according to claim 1, characterized in that the elastic compensation device (50) comprises an elastic element (5) arranged between the external end (9) of the ribbon (2) and the immobile support (7), as well as prestressing means (6) for applying a variable force or torque on the elastic element (5) as a function of the external pressure. 3. Regulating member according to claim 2, characterized in that the preloading means (6) comprise a spring part connected to the elastic element (5), the spring part transmitting the force or torque to the elastic element (5 ). 4. Regulating member according to claim 3, characterized in that the prestressing means (6) comprise an aneroid capsule whose volume varies as a function of the external pressure, so as to transmit a variable force or torque as a function of the pressure exterior. 5. Regulating member according to claim 4, characterized in that the aneroid capsule comprises a movable wall (13) and a stationary wall (15) connected by at least one spring (16). 6. Regulating member according to any one of the preceding claims, characterized in that the spring part comprises a first flexible blade (11) connected to the elastic element (5). 7. Regulating member according to claim 5 and any one of claims 3 and 4, characterized in that the spring part comprises a translation table (33) connected to the first flexible blade (11), the aneroid capsule being in contact with the translation table (33). 8. Regulating member according to claim 6, characterized in that the elastic part comprises a first movable element (22) connected to the first flexible blade (11), and a second movable element (28), the first movable element (22) and the second movable element (28) being connected by a pair of parallel flexible blades (25). 9. Regulating member according to claim 8 and any one of claims 3 and 4, characterized in that the spring part comprises a second flexible blade (21) connecting the second movable element (28) to the aneroid capsule. 10. Regulating member according to any one of the preceding claims, characterized in that the elastic element (5) comprises a suspended point body (3) and a pair of uncrossed blades (4) connecting the suspended point body (3). ) to the first immobile support (7). 11. Regulating member according to claim 9, characterized in that the prestressing means (6) are connected to the suspended point body (3) to exert the force or torque on the suspended point body (3). 12. Regulating member according to any one of the preceding claims, characterized in that it comprises means for adjusting the prestressing means (6) to apply a variable force (49, 59) on the prestressing means (6). ), for example on the first elongated movable element (22). 13. Regulating member according to any one of the preceding claims, characterized in that the regulating member (1, 10) extends substantially in the same plane, except for the oscillating mass. 14. Clock movement comprising a regulating member (1, 10), according to any one of the preceding claims.