Device for separating wound balance springs after expansion cycle, and method of manufacturing balance spring comprising separation step carried out by such device

Abstract

To provide a device for separating an assembly of balance springs which have been wound in and undergone an expansion cycle.SOLUTION: A device 100 for separating an assembly 10 of balance springs 12 that have been wound in and undergone an expansion cycle is provided, the device 100 comprising a support 110 having notches 113 intended to receive inner strands of the wound balance springs 12 making up the assembly, and a vibrating table 120 configured to define a vibration plane and to be movable along two different axes extending in the same plane, the vibrating table 120 also being configured to cause the support 110 to vibrate in a plane parallel to the vibration plane.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a method for manufacturing hairsprings intended to be equipped on the template or balance of a watch movement, and to a method for manufacturing such hairsprings.

[0002] The present invention relates to an apparatus for separating a hairspring in a method for manufacturing a hairspring, which facilitates the step of separating the hairspring after heat treatment.

[0003] The present invention further relates to a method for manufacturing a hairspring intended to be equipped on the balance of a watch movement.

Background Art

[0004] The manufacture of watch hairsprings is subject to the following constraints that at first glance do not seem to be compatible. · The need to obtain a high yield strength, · Ease of manufacture, specifically the ease of operations such as wire drawing and roller rolling, · Excellent fatigue strength, · A stable performance level over a long period, · A small cross-section That is.

[0005] Furthermore, the manufacture of hairsprings places further emphasis on consideration for thermal compensation in order to guarantee stable chronometer performance. For this purpose, it is necessary to obtain a thermal expansion coefficient close to zero. Also, hairsprings with limited sensitivity to magnetic fields are required.

[0006] That is, improvement in at least one of these points, specifically limited sensitivity to magnetic fields, thermal compensation, and ease of manufacture, particularly operations such as drawing, wire drawing, and roller rolling, represents a significant advance.

[0007] In the manufacturing cycle of the eyebrow trimmer, the winding operation consists of winding, by means of a winding star or spindle, a plurality of roller-rolled wires in a barrel so as to form an assembly or plate consisting of a plurality of eyebrow trimmers wound in the same plane.

[0008] The assembly typically includes three to six helically wound wires.

[0009] Subsequently, the various windings in the eyebrow trimmer are then fixed by an expansion cycle, typically a heat treatment, in order to obtain the final Archimedes spiral shape, as well as to obtain the desired thermoelastic coefficient (TEC) and to increase the hardness. The next step involves separating the various interlocking windings in the eyebrow trimmer.

[0010] This step can be particularly difficult in the case of compensated eyebrow trimmers. It is even more difficult in the case of eyebrow trimmers made of titanium alloy. This is because the presence of titanium in the alloy increases the frictional force between the various eyebrow trimmers.

[0011] As a result, there is a need to improve this step of separating the eyebrow trimmer after winding and heat treatment in order to minimize the rejection rate when manufacturing such eyebrow trimmers, especially compensated eyebrow trimmers.

Summary of the Invention

[0012] In this context, the present invention proposes a device for separating an assembly of wound and expanded-cycle eyebrow trimmers. This device comprises · a support including a notch intended to receive the inner strand of the wound eyebrow trimmers constituting the assembly, · a vibrating table movable along two different axes extending in the same plane, defining a vibration plane P1, and configured to vibrate the support in a plane parallel to the vibration plane P1 including

[0013] Such a device facilitates the separation of multiple assemblies of multiple coiled springs after heat treatment. Such a device is particularly effective for compensating hairsprings, specifically hairsprings made of titanium alloys.

[0014] Preferably, the two vibration axes are orthogonal to each other.

[0015] By vibrating in two directions in the same plane, a vibratory movement can occur particularly in the tangential direction of the coils of the hairspring.

[0016] By matching the shapes of the multiple coils, such vibration starts from the center of the assembly and propagates towards the outermost coils of the multiple hairsprings, elastically deforming the individual coils of the multiple hairsprings.

[0017] In addition to the features described above, the device according to the present invention has one or more complementary features from the following, considered on an individual basis or according to any technically possible combination, namely, · The vibration table vibrates in a circular translational motion, · The support includes a main body integrated with the vibration table and a spindle integrated with the main body, and the spindle extends perpendicular to the main body and the vibration plane P1 of the vibration table, · A notch is formed at the free end of the spindle, · The shape of the free end of the spindle is conical, · The device includes an air ejector for discharging the separated hairsprings when the vibration table is vibrated, · The device includes a recovery tray for receiving the discharged hairsprings, · The device includes a removable cover configured to at least partially cover the free end of the spindle, · The removable cover is movable between a closed position that prevents the moustache spring from being removed from the support and an open position that allows the assembly of the wound moustache spring to be inserted into the support and that allows the moustache spring separated from the support to be removed. · The removable cover is capable of translational movement along an axis perpendicular to the vibration plane P1 of the vibration table. · The removable cover includes a recess configured to receive the free end of the spindle when in the closed position. · The device includes a motor configured to vibrate the vibration table at a frequency between 1,000 Hz and 12,000 Hz, preferably between 4,000 Hz and 8,000 Hz. · The motor is an air motor or a piezoelectric motor. It may have.

[0018] Another aspect of the present invention relates to a method for manufacturing a moustache spring intended to be equipped on a template or balance of a watch movement.

[0019] According to the present invention, this manufacturing method particularly includes a step of separating an assembly of wound and inflated-cycle moustache springs, and this step is performed by implementing a separating device according to the present invention.

[0020] Preferably, the manufacturing method includes a winding step of winding a plurality of roller-rolled wires into a barrel by a winding star so as to form an assembly of wound moustache springs before the separating step.

[0021] Preferably, the manufacturing method includes an inflation step of relaxing the internal stress of the wound moustache spring of the assembly after the winding step.

[0022] Preferably, the moustache spring is a compensation spring.

[0023] Preferably, the beard spring is made of an alloy of niobium and titanium.

Brief Description of the Drawings

[0024] The objects, advantages, and features of the present invention will be better understood by reading the detailed description given below with reference to the following drawings.

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0026] In the manufacturing cycle of the hairspring, the winding operation consists of winding a plurality of roller-rolled wires into the barrel 2 (shown in Figure 6) by means of a star piece or a winding spindle. An assembly or plate consisting of a plurality of wound wires positioned and wound in the same plane is formed. After this step, the wound wire is considered to be wound around the hairspring. This is because its shape is definitive and is forced by the barrel 2.

[0027] Thereafter, the various wound springs constituting the assembly 10 are fixed by an expansion cycle, typically a heat treatment, to obtain the final shape of an Archimedean spiral having a regular pitch.

[0028] Figure 6 schematically shows an assembly 10 of a plurality of wound hairsprings 12 fixed by an expansion cycle.

[0029] Figure 7 shows the hairspring 12 in its final state. This hairspring 12 is intended to be equipped in the balance of a watch movement.

[0030] Typically, the assembly 10 consists of 3 to 6 hairsprings 12. In the example shown, the assembly 10 consists of 4 hairsprings 12.

[0031] The next step involves separating the various wound and thermally fixed hairsprings 12 of the assembly 10.

[0032] Figure 1 schematically shows an exemplary embodiment of an apparatus 100 for separating an assembly 10 consisting of a plurality of wound and thermally fixed springs 12.

[0033] The apparatus 100 will be described with reference to Figures 1 to 4 which schematically show different states of the apparatus 100 during the operation of separating the hairsprings 12.

[0034] The device 100 includes a support 110 configured to receive and hold the assembly 10 during the separation operation.

[0035] Specifically, the support 110 includes a base or body 111 and a spindle 112 extending perpendicular to the general plane formed by the body 111.

[0036] The spindle 112 has a plurality of notches 113 at its free end. Preferably, the number of notches is greater than or equal to the number of turns of the coil springs constituting the assembly 10. That is, in the illustrated exemplary embodiment, the spindle 112 includes four notches 113 evenly distributed around the circumference of the spindle 112.

[0037] Preferably, the free end that at least partially bears the notch 113 has a conical outer shape so as to facilitate the positioning of the assembly 10 or the removal of the individual separated whiskers 12.

[0038] The notch 113 is configured to receive the inner strand 13 of the wound whisker 12 and is configured to hold the assembly 10 at a predetermined distance from the body 111. That is, the various wound whiskers 12 of the assembly 10 are held by the device 100 only by the inner strands that form the inner ends of the wound whiskers 12. The various coils of the wound whisker 12 are suspended on the body 111 of the support 110.

[0039] The device 100 includes a vibration table 120 that vibrates along two different axes extending in the same plane, two different axes that define the vibration plane P1 shown in FIG. 4.

[0040] Preferably, the two vibration axes are perpendicular to each other.

[0041] The vibration table 120 performs a circular translational motion in the vibration plane P1 as shown in FIG. 4.

[0042] The annular translational motion is defined as a planar motion in which all points on the vibration table 120 have trajectories that are circles of the same radius but different centers.

[0043] The vibration table 120 vibrates by being mechanically driven by a motor (not shown). For example, the motor is an air motor or a piezoelectric motor.

[0044] The motor vibrates the vibration table 120 at a frequency between 1,000 Hz and 12,000 Hz, preferably between 4,000 Hz and 8,000 Hz, for example, at a frequency of 6,000 Hz.

[0045] The amplitude, frequency, and vibration power of the vibration table 120 can be modified via a man-machine interface (not shown).

[0046] The vibration table 120 is integrated with the main body 111 such that the support 110 also vibrates in a plane parallel to the vibration plane P1.

[0047] The device 100 further includes a removable cover 150 or lid. The removable cover 150 or lid is configured to at least partially cover the free end of the spindle 112 so as to limit the axial movement of the assembly 10 and the separated beard trimmer 12 along the longitudinal axis z of the spindle 112 when the support 110 is vibrated.

[0048] The removable cover 150 includes an opening or recessed area recessed from its lower surface, i.e., the surface facing the vibration table 120. This opening or recessed area forms a recess 151 configured to receive the free end of the spindle 112 when the removable cover 150 is in the closed position.

[0049] The removable cover 150 is movable between a closed position and an open position. The closed position restricts the movement of the beard trimmer along the z-axis of the spindle 112 and prevents the beard trimmer 12 from being removed from the spindle 112 of the support 110. The open position allows the wound beard trimmer assembly 10 to be inserted into the support 110 and to be removed once the beard trimmer 12 has been separated.

[0050] Preferably, the removable cover 150 can translate along an axis perpendicular to the vibration plane P1 of the vibration table 120. Preferably, the translation axis of the removable cover 150 coincides with the longitudinal axis z of the spindle 112.

[0051] The apparatus 100 further includes an ejector for removing the separated beard trimmer 12 from the support 110 in order to provide for a new cycle of separating the assembly 10. Preferably, the ejector 130 is an air ejector, for example a compressed air ejector.

[0052] The apparatus 100 further includes a collection tray 140 for collecting and gathering the various ejected beard trimmers 12.

[0053] The present invention further relates to a method 200 for manufacturing a beard trimmer intended to be fitted to the balance of a watch movement. This method includes at least one step 260 of separating a wound and thermally fixed beard trimmer. This step is implemented by the apparatus 100 according to the present invention.

[0054] The main steps of the manufacturing method 200 are given with reference to FIG. 5.

[0055] The manufacturing method 200 comprises the following successive steps, namely, · a step 210 of manufacturing a blank made of an alloy, preferably a compensation alloy, more particularly a titanium alloy, preferably an alloy containing niobium and titanium; · Step 220 of applying a precipitation bonding deformation - heat treatment sequence to the alloy, the sequence including applying deformation and heat treatment alternately until a desired microstructure is obtained, step 220; · A wire drawing step 230 that is performed until a wire with a round cross-section is obtained, and a roller rolling step 230 that manufactures a rectangular outer shape that conforms to the inlet cross-section of the draw spindle or star segment; · A winding step 240 that consists of winding a plurality of roller-rolled wires in a barrel by a winding spindle or star segment to form an assembly 10 of wound whiskers 12 in which various whiskers 12 are wound in the same plane; · An expansion step 250 of relaxing the stress in the assembly 10 of wound whiskers 12 to fix the final Archimedes spiral shape of the whiskers 12 by an expansion cycle; including.

[0056] The manufacturing method 200 further includes a separating step 260 of separating the whiskers that are thermally fixed at step 250. This separating step 260 is performed by the apparatus 100 in the following manner, that is, · In a first sub-step 261 shown in detail in FIG. 1, the assembly 10 formed by a plurality of wound and thermally fixed whiskers 12 is positioned on the spindle 112 of the support 110, whereby the inner strand 13 is positioned in the notch 113 of the spindle 112, and then the assembly 10 is suspended in the apparatus 100 while being held only by the inner strands 13 of the plurality of wound whiskers 12; · In a second sub-step 262 shown in detail in FIG. 2, the removable cover 150 is lowered so as to be positioned in the closed position, thereby preventing the loss of the assembly 10 mounted on the spindle 112, and the support 100 is vibrated by the vibration table 120, whereby an annular translational movement occurs in a plane parallel to one plane of the plurality of whiskers 12, and then the plurality of whiskers 12 are separated from each other so that they are no longer placed in the same plane; · In the third sub-step 263 shown in detail in FIG. 3, the removable cover 150 is raised to be positioned in the open position, and the air ejector 130 generates an air flow to discharge the plurality of separated beard hairs 12. It is implemented in such a manner.

Claims

1. A device (100) for separating an assembly (10) of a hairspring (12) that has been wound and has undergone an expansion cycle, comprising: a support (110) including a notch (113) intended to receive the inner strand (13) of the wound balance spring (12) constituting said assembly (10); a vibration table (120) movable along two different axes extending in the same plane, defining a vibration plane P1, the vibration table (120) being configured to vibrate the support (110) in a plane parallel to said vibration plane P1; An apparatus (100).

2. The apparatus (100) of claim 1, wherein the two vibration axes are orthogonal.

3. The apparatus (100) of claim 1, characterized in that the vibration table (120) vibrates in an annular translational motion.

4. 2. The apparatus (100) according to claim 1, characterized in that the support (11) comprises a body (111) integral with the vibration table (120) and a spindle (112) integral with the body (111), the spindle (112) extending perpendicular to the body (111) and to a vibration plane (P1) of the vibration table (120).

5. 5. The device (100) according to claim 4, characterized in that said notch (113) is formed in a free end of said spindle (112).

6. The device (100) according to claim 5, characterized in that the shape of the free end of the spindle (112) is conical.

7. 2. The apparatus (100) according to claim 1, characterized in that the apparatus (100) includes an air ejector (130) for ejecting the separated hairspring (12) when the vibration table is vibrated (120).

8. 8. The device (100) according to claim 7, characterized in that said device (100) includes a collection tray (140) for receiving said expelled hairspring (12).

9. The apparatus (100) of claim 5, characterized in that the apparatus (100) includes a removable cover (150) configured to at least partially cover the free end of the spindle (112).

10. 10. The device (100) according to claim 9, characterized in that the removable cover (150) is movable between a closed position that prevents the balance spring (12) from being removed from the support (110) and an open position that allows the assembly (10) of the wound balance spring (12) to be inserted into the support (110) and that allows the balance spring (12) separated from the support (110) to be removed.

11. 11. The apparatus (100) according to claim 10, characterized in that the removable cover (150) is translatable along an axis perpendicular to the vibration plane (P1) of the vibration table (120).

12. 11. The apparatus (100) of claim 10, wherein the removable cover (150) includes a recess (151) configured to receive the free end of the spindle (112) when the spindle (112) is in the closed position.

13. 2. The apparatus (100) according to claim 1, comprising a motor configured to vibrate the vibration table (120) at a frequency between 1,000 Hz and 12,000 Hz, preferably between 4,000 Hz and 8,000 Hz.

14. 14. The device (100) according to claim 13, characterized in that the motor is an air motor or a piezoelectric motor.

15. A method (200) for manufacturing a hairspring intended to be equipped to the balance of a timepiece movement, characterized in that said manufacturing method (200) comprises a step (260) of separating an assembly (10) of wound hairsprings (12) that have undergone an expansion cycle, said step being carried out by implementing a separating device (100) according to claim 1.

16. Method (200) for manufacturing a hairspring intended to be equipped in the balance of a timepiece movement, according to claim 15, characterized in that said method (200) comprises, before said separating step (260), a winding step (240) consisting of winding a plurality of roller-rolled wires into a barrel (2) by means of a winding star, so as to form an assembly (10) of said wound hairspring (12).

17. Method (200) for manufacturing a hairspring intended to be equipped in the balance of a timepiece movement, according to claim 16, characterized in that it comprises, after said winding step (240), an expansion step (250) for relieving stresses in the assembly (10) of the wound hairspring (12).

18. 16. Method (200) for manufacturing a hairspring intended to be equipped to the balance of a timepiece movement, according to claim 15, characterized in that said hairspring (12) is a compensation spring.

19. 19. Method (200) for manufacturing a hairspring intended to be equipped to the balance of a timepiece movement, according to claim 18, characterized in that said hairspring (12) is made from an alloy of niobium and titanium.

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