A template equipped with means for adjusting its temperature sensitivity

Abstract

To provide a balance, including means for adjusting the temperature sensitivity of the balance.SOLUTION: A balance 1 is for an adjusting member of a timepiece movement. The balance 1 includes, at least in part, a body 10 that can be deformed according to temperature, the deformable body 10 is arranged, at least in part, on the periphery of the balance 1, the balance 1 is configured to be able to move about a center of rotation 11, the balance 1 includes means 20 for adjusting the sensitivity of the deformable body 10 to temperature change, the adjustment means 20 includes a first inertial element 5 arranged on the deformable body 10 to be able to modify moment of inertia of the deformable body 10, the first inertial element 5 can move relative to the deformable body 10 into a plurality of positions, and the plurality of positions form a continuous set.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a template provided with means for adjusting its temperature sensitivity, particularly for the watch manufacturing industry.

Background Art

[0002] Most mechanical watches today are equipped with a hairspring-equipped balance and a Swiss lever escapement mechanism. The hairspring-equipped balance constitutes the time reference of the watch. This is also called an oscillator or a regulating member.

[0003] The escapement · maintains the reciprocating motion of the oscillator, · counts these reciprocating motions and has two main functions.

[0004] To form a mechanical resonator, an inertial element, a guide, and an elastic return element are required. Conventionally, the hairspring functions as the elastic return element of the inertial element constituted by the balance. This balance is generally guided in rotation by a pivot that rotates inside a ruby bearing.

[0005] The frequency is selected for the mechanical resonator and determined to obtain a predetermined speed for the watch movement.

[0006] However, during operation, such a mechanical resonator is subject to interference caused by changes in external parameters, which may lead to fluctuations in the frequency of the resonator. These parameters include, for example, temperature, pressure, humidity, and gravity. Fluctuations in the frequency of the resonator cause errors in the measurement of time and, consequently, in the speed of the watch movement.

[0007] In particular, with respect to temperature, there are balances that include a bimetal body that deforms under the influence of temperature, and the moment of inertia of the balance is changed to correct for differences in the speed of the regulating member caused by temperature fluctuations. Such a balance is described in Patent Document 1.

[0008] The template includes an annular bimetal body having two symmetrical free ends. Depending on the temperature, one or more free ends move away from or closer to each other, changing the moment of inertia of the template. Thus, the configuration of the template adapts to the temperature.

[0009] Furthermore, the sensitivity of the template to temperature changes can be adjusted. Thus, the influence of temperature changes is more or less significant, especially with regard to its effect on the moment of inertia of the template.

[0010] For this purpose, a plurality of holes are made in the body, and a screw is arranged in one of the holes at a long or short distance from the free end. Depending on the selected hole, the sensitivity to temperature changes becomes more or less significant. However, the number of holes in the template is limited, and the sensitivity can only be changed in jumps, not continuously.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0012] An object of the present invention is to overcome some or all of the aforementioned drawbacks by proposing a template provided with means for adjusting the temperature sensitivity of the template.

Means for Solving the Problems

[0013] For this purpose, the present invention provides a template for an adjusting member of a timepiece movement, the template being at least partially formed of a body deformable according to temperature, the deformable body being at least partially disposed around the template, the template being configured to be movable around a center of rotation, the template comprising means for adjusting the sensitivity of the deformable body to temperature changes, the adjusting means comprising a first inertial element cooperating with the deformable body so as to be able to change the moment of inertia of the deformable body, the first inertial element being movable at a plurality of positions on the deformable body, with respect to the template.

[0014] The present invention is notable in that the plurality of positions form a continuous set.

[0015] Thanks to the present invention, the adjusting means makes it possible to adjust very precisely the sensitivity of the template to temperature changes as compared with adjusting means operating by discrete adjustment. This is because the number of positions is less restricted and there are no inaccessible gaps between two consecutive positions.

[0016] According to a particular embodiment of the present invention, the first inertial element is arranged at a substantially constant distance from the center of rotation, regardless of the position of the first inertial element with respect to the deformable body, for a given configuration of the deformable body with respect to the center of rotation.

[0017] According to a particular embodiment of the present invention, the first inertial element is movable substantially tangentially with respect to the template.

[0018] According to a particular embodiment of the present invention, the deformable body comprises a first free end at the periphery, and the first inertial element is arranged at the first free end.

[0019] According to a particular embodiment of the present invention, the adjusting means comprises a second inertial element movable at a plurality of positions forming a continuous set with respect to the deformable body.

[0020] According to a particular embodiment of the present invention, the deformable body comprises a second free end, and the second inertial element is arranged at the second free end such that it is movable substantially tangentially with respect to the deformable body.

[0021] According to a particular embodiment of the present invention, the first inertial element and the second inertial element are screws, and each screw is screwed into the body tangentially at the free end, more or less, in order to change their positions.

[0022] According to a particular embodiment of the present invention, the first inertial element and the second inertial element are arranged symmetrically with respect to the center of rotation.

[0023] According to a particular embodiment of the present invention, the deformable body has an at least partially annular peripheral shape.

[0024] According to a particular embodiment of the present invention, the deformable body includes a first annular part with a first free end and a second annular part with a second free end.

[0025] According to a particular embodiment of the present invention, the first annular part and the second annular part each include a bimetal attachment such that they are deformable according to temperature.

[0026] According to a particular embodiment of the present invention, the two annular parts are connected by a radial part.

[0027] According to a particular embodiment of the present invention, the two annular parts are arranged symmetrically with respect to the center of rotation.

[0028] The present invention further relates to an adjusting member including such a template.

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

Brief Description of the Drawings

[0030] The objects, advantages, and features of the present invention are provided for illustrative purposes only and are not intended to limit the scope of the present invention, and will become apparent by reading some embodiments given with reference to the accompanying drawings.

Figure 1

Figure 2

DETAILED DESCRIPTION OF THE INVENTION

[0031] FIGS. 1 and 2 show embodiments of a template for an adjustment member of a clock according to the present invention.

[0032] The template 1 includes a rotation shaft 2 that enables the template 1 to rotate when disposed within the adjustment member. The template 1 further includes a deformable body 10 that is deformable according to temperature. The deformable body 10 is attached to the rotation shaft 2, and the template 1 is movable around a rotation center 11 located on the rotation shaft 2.

[0033] The deformable body 10 has a peripheral shape that is at least partially annular. The deformable body includes a first annular portion 3 and a second annular portion 4.

[0034] The two annular portions 3, 4 are connected by a radial portion 7 attached to the rotation shaft 2, and the radial portion 7 is preferably attached to the rotation shaft 2 at its center.

[0035] Each annular portion 3, 4 extends symmetrically with respect to the rotation shaft 2 and the rotation center 11 and is connected at opposite ends of the radial portion at positions opposite to each other.

[0036] Each annular portion 3, 4 draws a curve of equal radius and preferably forms an arc equal to each other. Thus, the two annular portions 3, 4 form a ring that is open at two opposing points symmetric with respect to the rotation center 11.

[0037] The first annular part 3 has a first free end 12, and the second annular part 4 has a second free end 13. The two free ends 12, 13 are arranged in two open positions. Each free end 12, 13 is arranged at one end of the annular parts 3, 4.

[0038] The first annular part 3 and the second annular part 4 are each formed by a bimetal attachment so as to be deformable according to temperature. The bimetal attachment is composed of two layers of different materials 8, 9 that enable the bimetal attachment to deform according to temperature in a predetermined direction. Therefore, the two annular parts 3, 4 are deformable according to temperature.

[0039] Under the influence of temperature, the annular parts 3, 4 deform more or less so that the free ends 12, 13 move further away from or closer to the rotation center 11. Therefore, the moment of inertia of the template 1 is changed to maintain a substantially constant speed.

[0040] In FIG. 1, the free ends 12, 13 of the annular parts 3, 4 are close to the center 11, but in FIG. 2, the free ends 12, 13 are located far from the rotation center 11.

[0041] To adjust the sensitivity of the template 1 to temperature, the template 1 further includes means 20 for adjusting the sensitivity of the deformable body 10 to temperature changes.

[0042] The adjusting means 20 includes a first inertia element 5 arranged on the deformable body 10 so as to be able to change the moment of inertia of the deformable body 10. The first inertia element 5 is arranged at the surrounding first free end 12.

[0043] Preferably, the adjusting means 20 includes a second inertia element 6 arranged at the second free end 13. The first inertia element 5 and the second inertia element 6 are arranged symmetrically with respect to the rotation center 11. Therefore, the adjusting means 20 has a substantially symmetrical configuration.

[0044] In this embodiment, the first inertial element 5 and the second inertial element 6 are screws arranged such that they are screwed into the respective free ends 12, 13 more or less. The screws have high resistance to impact and gravity.

[0045] The inertial elements 5, 6 are movable relative to the deformable body 10 at a plurality of positions.

[0046] According to the present invention, the plurality of positions form a continuous set. Therefore, the sensitivity of the adjusting means 20 can be adjusted accurately and continuously.

[0047] The first inertial element 5 and the second inertial element 6 are each movable relative to the deformable body 10 in a substantially tangential direction. Therefore, each screw is screwed into the template more or less in the tangential direction, particularly in the tangential direction with respect to the deformable body 10, at the free ends 12, 13 in order to change the position with respect to the deformable body 10.

[0048] Thanks to this arrangement, each inertial element 5, 6 maintains a substantially constant distance from the rotation center 11 for a given deformation of the annular portions 3, 4, regardless of the position of each inertial element 5, 6 with respect to the deformable body 10. The distance from the rotation center 11 does not change depending on the degree to which the screw is screwed in.

[0049] The distance between each inertial element 5, 6 and the rotation center 11 can change due to the deformation of the annular portions 3, 4 under the influence of temperature changes. However, the movement of the inertial elements 5, 6 relative to the deformable body 10 does not cause any change in the distance between the inertial elements 5, 6 and the rotation center 11 for a given configuration of the deformable body 10.

[0050] The present invention further relates to an adjusting member (not shown in the figures) including the template 1. The present invention further relates to a movement including such an adjusting member.

[0051] Needless to say, the present invention is not limited to the embodiments described with reference to the drawings, and alternatives can be considered without departing from the scope of the present invention.

Claims

1. A balance (1) for a regulating member of a timepiece movement, said balance consisting at least in part of a deformable body (10) which is deformable as a function of temperature, said deformable body (10) being at least in part arranged on the outer circumference of said balance (1), said balance (1) being arranged so as to be movable around a centre of rotation (11), said balance (1) being provided with adjustment means (20) for adjusting the sensitivity of said deformable body (10) to temperature variations, said adjustment means (20) comprising a first inertial element (5) arranged on said deformable body so as to be able to modify the moment of inertia of said balance (1), said first inertial element (5) being movable relative to said deformable body (10) in a number of positions, said number of positions forming a continuous set, A balance, characterized in that said first inertial element (5) is movable substantially tangentially with respect to said deformable body (10).

2. 2. A balance according to claim 1, characterized in that the first inertial element (5) is arranged at a substantially constant distance from the centre of rotation (11), for a given configuration of the deformable body (10) relative to the centre of rotation (11), regardless of the position of the first inertial element (5) relative to the deformable body (10).

3. 2. A balance according to claim 1, characterized in that said deformable body (10) comprises a peripheral first free end (12) and said first inertial element (5) is arranged at said first free end (12).

4. 2. A balance according to claim 1, characterized in that said adjustment means comprise a second inertial element (6) movable in a plurality of positions forming a successive set relative to said deformable body (10).

5. 5. A balance according to claim 4, characterized in that said deformable body (10) comprises a second free end (13) and said second inertial element (6) is arranged at said second free end (13) so as to be movable substantially tangentially relative to said balance.

6. 5. A balance according to claim 4, characterized in that the first (5) and the second (6) inertial elements are screws, each screwed more or less tangentially at its free end (12, 13) relative to the deformable body in order to change the position of the first (5) and the second (6) inertial elements.

7. 7. A balance according to any one of claims 4 to 6, characterized in that the first inertia element (5) and the second inertia element (6) are arranged symmetrically with respect to the centre of rotation (11).

8. 2. A balance according to claim 1, characterized in that the deformable body (10) has a peripheral shape that is at least partially annular.

9. 9. A balance according to claim 8, characterized in that the deformable body (10) comprises a first annular portion (3) with a first free end (12) and a second annular portion (4) with a second free end (13).

10. 10. A balance according to claim 9, characterized in that the first annular part (3) and the second annular part (4) respectively comprise a bimetallic attachment such that the first annular part (3) and the second annular part (4) are deformable as a function of temperature.

11. 10. A balance according to claim 9, characterized in that the first annular portion (3) and the second annular portion (4) are connected by a radial portion.

12. 10. A balance according to claim 9, characterized in that the first annular part (3) and the second annular part (4) are arranged symmetrically with respect to the centre of rotation (11).

13. 2. A regulating member, characterized in that it comprises a balance (1) according to claim 1.

14. A clock movement, characterized in that it comprises a regulating member according to claim 13.

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