Regulating member, timepiece movement, and timepiece

Abstract

To overcome some or all of drawbacks in the conventional index systems by providing an actuation system compatible with a regulating device.SOLUTION: A regulating member 1 for a horological movement is provided, including an inertial mass, for example a balance 23, a balance spring 25, a balance cock 22, and an actuation system 20 for adjusting the rate of the balance spring. The balance spring includes a coiled ribbon and means 30 of adjusting stiffness of the balance spring, where the means is provided with a resilient element arranged in series with the coiled ribbon. The adjustment means includes a pre-stress device for applying a variable force or torque to the flexible (resilient) element. The actuation system includes an eccentric 10 for actuating the pre-stress means) of the adjustment means.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of watchmaking, and more particularly to the field of mechanical watchmaking in which the driving energy is regulated by a regulating member. Even more particularly, the present invention relates to a regulating member provided with a precise operating system for adjusting the speed of the hairspring, to a watch movement including such a regulating member, and to a watch including such a watch movement.

Background Art

[0002] In most mechanical watches, the energy required to rotate the hands (e.g., the minute hand and the hour hand) is stored in a barrel and then conveyed by a spring balance system including a balance, which is a flywheel combined with a spring in the form of a spiral ribbon called a hairspring.

[0003] The inner end of the hairspring is attached to a staff that rotates integrally with the balance, and the outer end of the hairspring is attached to a stud mounted on a stud holder that is rigidly connected to a stationary cock.

[0004] The rotation of the balance is maintained by an escapement mechanism including a pallet lever driven by low-amplitude vibrations provided with two pallets that engage the teeth of the escape wheel, and the vibrations are counted. When the escape wheel engages in this way, the escape wheel rotates stepwise, and the frequency of its rotation is determined by the frequency of the vibrations of the pallet lever. The pallet lever itself is set to the frequency of the vibrations of the spring balance.

[0005] In a conventional escapement mechanism, the frequency is about 4 Hz, i.e., about 28,800 vibrations per hour (V / h). One of the aims of an excellent watchmaker is to ensure the isochronism and regularity (or constancy of speed) of the vibrations of the balance.

[0006] The speed of the beard escapement can be regulated in a known manner, namely by adjusting the effective length of the beard escapement. The effective length of the beard escapement is defined as the curve length between the inner end of the beard escapement and a typical count point carried by a pair of bankings arranged in the vicinity of the outer end of the beard escapement and supported by a key mounted on the index system.

[0007] During operation, this index system cannot rotate about the axis of the beard escapement. However, its angular position can be finely adjusted by manual intervention, for example, by pivoting an eccentric that acts like a cam on the index system using a screwdriver.

[0008] An assembly including a cock, an index system, a key, a stud holder, a stud, a staff, a spring, and a balance is generally referred to as a "regulating member". Examples of regulating members are given in Patent Documents 1 and 2, both of which are filed by the watch manufacturer ETA.

[0009] There is an index system having a stud holder to which the outer end of the beard escapement is attached. Here, the key of the index system leaves a play that allows the beard escapement to move between two bankings. However, the chronometer characteristics, especially the asynchronism, are very sensitive to the play in the index key, and it is difficult to accurately control this play.

[0010] In some devices, in order to eliminate play, especially when the beard trimmer is operating, the banking can be adjusted to clamp the beard trimmer. In this case, first move the index key to regulate the speed, and then clamp the beard trimmer to the key. However, when clamping the beard trimmer to the index key, there is a risk of burdening the beard trimmer and particularly causing the center of winding to shift, resulting in a chronometer error. Furthermore, since eliminating play also changes the speed, once the beard trimmer is clamped, the index key can no longer be moved along the beard trimmer to finely adjust the speed.

[0011] In other beard trimmers, a regulating device is integrated. In these beard trimmers, the speed is not regulated by modifying the effective length of the beard trimmer, but by applying a force or torque to an elastic element arranged in series with the beard trimmer. In this way, the rigidity of the elastic element, and thus the rigidity of the entire beard trimmer, can be corrected. By adjusting the rigidity of the beard trimmer, it is allowed to regulate the speed of the regulating member. Such a beard trimmer with an elastic element is described, for example, in Patent Document 3.

[0012] However, in these cases, the normal index system cannot be used because it is not compatible with the beard trimmer regulating device. Furthermore, since it is necessary to very finely adjust the speed, it is essential that there is no play between the beard trimmer and the area where the beard trimmer interacts with the index mechanism. Specifically, if not, in the event of an impact, there is a risk that the speed will be altered if the beard trimmer does not relocate itself exactly the same after the impact.

Prior Art Documents

Patent Documents

[0013]

Patent Document 1

Patent Document 2

[0014] The object of the present invention is to overcome some or all of the above-mentioned drawbacks by providing an operating system that is particularly adapted to this type of regulating device.

[0015] For this purpose, the present invention relates to a regulating member for a watch movement comprising an inertial mass, such as a balance, a hairspring, a balance cock, and an operating system for adjusting the speed of the regulating member, the hairspring comprising a coiled ribbon and means for adjusting the stiffness of the hairspring, the means comprising an elastic element arranged in series with the coiled ribbon, and the adjusting means comprising prestressing means for applying a variable force or torque to the flexible element.

[0016] The present invention is characterized in that the operating system comprises an eccentric for actuating the prestressing means of the adjusting means.

[0017] Thanks to the present invention, the speed of the regulating member can be adjusted simply by changing the position of the eccentric, which acts on the prestressing means so as to adjust the speed of the regulating member.

[0018] In a particular embodiment of the present invention, the eccentric is arranged so as to pass through the balance cock, whereby the eccentric is rotatably mounted.

[0019] In a particular embodiment of the present invention, the eccentric comprises a head and a body extending from the head.

[0020] In a particular embodiment of the present invention, the body comprises a finger extending from the body, the finger being offset with respect to the axis of the main body of the eccentric.

[0021] In certain embodiments of the present invention, the head includes a recess intended to receive the tip of a tool used to operate the eccentric.

[0022] In certain embodiments of the present invention, the prestressing means includes a first movable lever connected to a flexible element, and the eccentric is in direct or indirect contact with the first lever so as to be able to operate the first lever.

[0023] In certain embodiments of the present invention, the prestressing means includes a second movable lever connected to a flexible element, and the eccentric is in direct or indirect contact with the second lever so as to be able to operate the second lever.

[0024] In certain embodiments of the present invention, the prestressing means includes a movable body connected to the first lever and / or the second lever, and the finger is in contact with the movable body so as to be able to move the movable body.

[0025] In certain embodiments of the present invention, the finger includes a peripheral groove that cooperates with the movable body.

[0026] In certain embodiments of the present invention, the actuation system includes a stud holder that includes a stud on which the hairspring is mounted, and the stud is mechanically connected to the elastic element of the hairspring.

[0027] In certain embodiments of the present invention, the stud is mechanically connected to the elastic element.

[0028] In certain embodiments of the present invention, the stud holder is disposed on the balance cock around a bearing on the balance staff.

[0029] The present invention further relates to a timepiece movement including such a regulating member.

[0030] The present invention further relates to a timepiece, such as a wristwatch, including such a timepiece movement.

Brief Description of the Drawings

[0031] The objectives, advantages, and features of the present invention will become apparent after reading several embodiments. These embodiments are provided for illustrative purposes only and are not intended to limit the scope of the present invention on the premise of reference to the accompanying drawings.

[0032]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0033] FIGS. 1 to 5 schematically show a first embodiment of a regulating member 1 intended to be disposed in a timepiece movement (not shown). Such a timepiece movement includes, for example, a plate having a recess for receiving the regulating member 1 provided with an inertial mass, and an elastic return element for the inertial mass configured to vibrate the inertial mass.

[0034] The regulating member 1 further includes an operating system 20, an annular balance 23 as an inertial mass, a balance staff 24, a hairspring 25 as an elastic return element, and a balance cock 22.

[0035] In FIGS. 1 to 3, the balance 23, the hairspring 25, the balance cock 22, and the operating system 20 are, in this case, stacked from bottom to top.

[0036] The whisker spring 24 is centrally located and passes through the center of the balance 23, the center of the whisker spring 25, and the balance cock 22. The balance staff 24 is held by two shock-resistant bearings 28 arranged at both ends of the balance staff 24. A first bearing (not shown) is arranged under the balance 23 and the balance cock 22, and the second bearing 28 is held by the balance cock 22. The balance cock 22 has a hole (in this case, a through-hole), and the second bearing 28 is held therein. The operating system 20 is mounted on the balance cock 22 and, in this embodiment, is arranged along the central axis of the balance staff 24.

[0037] FIG. 5 shows an example of the whisker spring 25 preferably extending substantially in a plane. The whisker spring 25 includes a flexible ribbon 2 wound around itself several times, and the ribbon 2 has a predetermined rigidity. The inner end 9 of the ribbon 2 is integrated with or assembled to a support 3 generally referred to as a collet. The support 3 is substantially triangular in shape and is screwed around the balance staff 24.

[0038] The whisker spring 25 further includes means 30 for adjusting its rigidity. For example, the adjusting means 30 can be actuated by the user, especially when the regulating member is mounted on the plate of the timepiece movement.

[0039] The adjusting means 30 includes a flexible element 5 arranged in series with the ribbon 2. The flexible element 5 connects one end 4 of the ribbon 2 to a fixed support 53 and is integral with one end 4 of the ribbon 2. The flexible element 5 is integral with the outer end 4 of the ribbon 2. The elastic element 5 is a different element from the ribbon 2.

[0040] The flexible element 5 adds additional rigidity to the rigidity of the ribbon 2. The flexible element 5 is preferably harder than the ribbon 2. In this case, the flexible element 5 is arranged as an extension of the ribbon 2. Preferably, the adjusting means and the strip 2 are integral or made of the same material, such as silicon.

[0041] In the beard trimmer of this embodiment, the flexible element 5 includes two flexible portions 15, 16 each connecting the ribbon 2 to the fixed support 53.

[0042] The two flexible portions 15, 16 are arranged axially symmetrically with respect to each other along the axis A of the beard trimmer 25. In other words, the two flexible portions 15, 16 are positioned symmetrically with respect to the axis A.

[0043] On the one hand, the axis A substantially passes through the center O of the beard trimmer, and on the other hand, the axis A preferably passes through the outer end 4 of the ribbon 2.

[0044] Therefore, the two flexible portions 15, 16 are arranged on the outer periphery of the beard trimmer so as to be arranged at the same distance from the center O of the beard trimmer.

[0045] The two flexible portions 15, 16 are preferably arranged in a "mirror-like" positional relationship with respect to each other with respect to the axis A. For this purpose, the two flexible portions 15, 16 are preferably substantially identical.

[0046] Each of the flexible portions 15, 16 includes a curved flexible strip 55. This preferably forms a semi-circle and extends from the end of the fixed support 53. Each curved flexible strip 55 is also connected to the outer end 4 of the ribbon 2 by a main flexible strip 7. In this case, the main flexible strips 7 are arranged continuously with respect to each other.

[0047] The fixed support 53 has a trapezoidal shape with the long side open towards the outer end 4 of the ribbon 2.

[0048] The means for adjusting the beard trimmer 25 further includes prestressing means 6 for applying a variable force or torque to the flexible element 5. In this way, the rigidity of the beard trimmer can be adjusted. The torque or force can be continuously adjusted by the prestressing means 6. In other words, the torque or force is not limited to an isolated value. The rigidity of the flexible element 5 can therefore be adjusted very precisely.

[0049] Preferably, the prestressing means 6 applies substantially the same force or torque to each flexible portion 15, 16. The direction of the force is preferably substantially symmetric with respect to the axis A.

[0050] The prestressing means 6 further includes two levers 14, 26. Each lever connects a curved strip 55 to the same movable body 19 arranged on the opposite side of the toggle 25 with respect to the fixed support 53. In this case, the movable body 19 has a hook shape.

[0051] A variable force or torque is applied to the movable body 19. The variable force or torque is at least partially transmitted via the lever 26 to the main flexible strips 7 of the flexible portions 15, 16 of the flexible element 5.

[0052] In the embodiment shown in FIGS. 1 to 4, the operating system 20 is fitted into a stud holder 31 provided with a stud 34.

[0053] The stud holder 31 contacts the balance cock 22 and is held and positioned by the shock absorber 28.

[0054] During the operation of the regulating member 1, it is preferable that the stud holder 31 is stationary with respect to the balance cock 22.

[0055] The stud holder 31 includes a central ring 38 arranged around the second bearing 28.

[0056] The stud holder 31 includes a protrusion 41 extending radially from the central ring 38, and the protrusion 41 presses the stud 34 with a screw 74.

[0057] The stud 34 cooperates with the fixed support 53 of the elastic element 57. Thus, the elastic element 5 is held by the stud. The toggle 25 is held on one hand by the elastic element 5 and on the other hand by the support 3.

[0058] The prestressing means 6 is also supported by the stud holder 31.

[0059] The stud and the brushless motor 25 are assembled, for example, by adhesion, brazing, welding, deformation of a metallic glass, or mechanical fastening.

[0060] In order to be able to apply a variable force or torque to the brushless motor 25, the regulating member includes an actuating system 20.

[0061] According to the invention, the actuating system 20 includes a rotatable eccentric 10 which cooperates with the brushless motor 25 so as to modify its stiffness.

[0062] The eccentric 10 includes a head 21 having a recess 18 for receiving the tip of a tool for adjusting the eccentric 10. The eccentric 10 has a preferably cylindrical body 11 extending from the head 21.

[0063] The eccentric 10 further includes a finger 12 which is offset with respect to the main axis of the body 11 of the eccentric 10. The finger 12 extends from the body 11. The finger 12 is mechanically connected to the prestressing means 6 without blocking the ribbon 2.

[0064] The eccentric 10 is arranged so as to pass through a balance cock 22. The balance cock 22 includes a flared through-hole 17 for holding the head 21 of the eccentric 10 and for enabling the body 11 and the finger 12 to pass through to the opposite side of the balance cock 22.

[0065] The eccentric 10 is held below the balance cock 22 by a clamp 29 clipped around the body 11 of the eccentric 10.

[0066] Preferably, the body 11 includes a groove 32 into which the clamp 29 is inserted for holding the eccentric 10 in the hole 17.

[0067] The eccentric 10 is rotatably mounted on the balance cock 22. Thus, the eccentric 10 can rotate at the hole 17 and at the clamp 29 about the main axis of the eccentric 10, preferably substantially perpendicular to the balance cock 22 and / or substantially parallel to the balance staff 24.

[0068] The fingers 12 of the eccentric 10 contact the movable body 19 of the prestressing means 6 and are able to press the levers 14, 26 to a greater or lesser extent when the eccentric 10 rotates.

[0069] Preferably, the fingers 12 include a peripheral groove 33 that cooperates with the movable body 19 of the hairspring 25, and the movable body 19 is inserted into the groove 33.

[0070] Thus, when the eccentric 10 rotates, since the fingers 12 are eccentric with respect to the main rotation axis of the eccentric 10, they press the movable body 19 to a greater or lesser extent.

[0071] The movement of the fingers 12 with respect to the movable body modifies the stiffness of the elastic element 5 because the movement exerts a greater or lesser force or torque on the movable body 19 of the prestressing means 6. Through the lever 26, the stiffness of the flexible parts 15, 16 of the elastic element 5 changes, and thus the overall stiffness of the hairspring 25 also changes. In this way, the operating system 20 can regulate the speed of the regulating member 1.

[0072] For this purpose, the position of the fingers 12 can be corrected using the operating system 20.

[0073] The operating system 20 is configured to adjust the speed of the regulating member 1 with a resolution of 1 second or less per day, preferably 0.5 second or less per day, and more preferably 0.1 second or less per day. Due to the configuration of the regulating member 1, such accuracy can be achieved.

[0074] The present invention is not limited to the embodiments of the regulating member described with reference to the drawings, and it goes without saying that alternatives can be considered without departing from the scope of the present invention.

Claims

1. A regulation member (1) for a timepiece movement comprising an inertial mass, for example a balance (23), a hairspring (25), a balance cock (22) and an actuation system (20) for adjusting the speed of the hairspring (25), said hairspring (25) comprising a coiled ribbon (2) and means (30) for adjusting the stiffness of said hairspring, said means comprising an elastic element (5) arranged in series with said coiled ribbon (2), said adjusting means (30) comprising prestressing means (6) for applying a variable force or torque to said flexible element (5), characterized in that said actuation system (20) comprises an eccentric (10) for actuating said prestressing means (6) of said adjusting means (30).

2. 2. The regulating member according to claim 1, characterized in that said eccentric (10) is rotatably mounted through said balance cock (22).

3. The restricting member according to claim 1, characterized in that the eccentric (10) includes a head (21) and a body (11) extending from the head (21).

4. 4. The limiting member of claim 3, wherein the eccentric (10) further comprises a finger (12) extending from the body (11), the finger (12) being off-center with respect to a major axis of the body (11) of the eccentric (10).

5. 4. The limiting member according to claim 3, characterized in that said head (21) comprises a recess (18) intended to receive the tip of a tool for actuating said eccentric (10).

6. 2. The regulating member according to claim 1, characterized in that the prestressing means (6) comprises a movable first lever (14) connected to the flexible element (5), and the eccentric (10) is in direct or indirect contact with the lever (14) so ​​as to be able to actuate the lever (14).

7. 7. The regulating member according to claim 6, characterized in that the prestressing means (6) comprises a second movable lever connected to the flexible element (5), the eccentric (10) being in direct or indirect contact with the second lever (26) so as to be able to actuate the second lever (26).

8. 7. The regulating member according to claim 6, characterized in that the prestressing means (6) comprises a movable body (19) connected to the first lever (14) and / or the second lever (26), and the finger (12) is in contact with the movable body (19).

9. 9. A restricting member according to claim 8, characterized in that said finger (12) comprises a peripheral groove (33) cooperating with said mobile body (19).

10. 2. A limiting member according to claim 1, characterized in that the actuation system (20) comprises a stud holder (31) including a stud (34) on which the hairspring (25) is mounted, the stud (34) being mechanically connected to the elastic element (5) of the hairspring (25).

11. 2. The restricting member according to claim 1, characterized in that the stud holder (31) is arranged in the balance cock (22) around a bearing (28) on the balance staff (24).

12. A clock movement, characterized in that it includes a regulating member (1) according to claim 1.

13. A timepiece, e.g. a wristwatch, comprising a timepiece movement according to claim 12.

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