Timepiece component with separate intersecting blades and method for manufacturing same
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-22
- Publication Date
- 2026-04-08
AI Technical Summary
Manufacturing watch components with separate crossed blades faces challenges in maintaining sufficient spacing between blades to prevent contact during operation and shocks, which can reduce precision and cause damage, and existing solutions like oxidation-deoxidation sequences or metal spacers are limited by precision and manufacturing tolerances.
A watch component design featuring an assembly of superimposed parts with integral spacers produced by engraving the same substrate, ensuring consistent height spacing between elastic blades, using a multilayer structure from SOI substrates to prevent blade contact and maintain precision.
The solution effectively maintains precise spacing between elastic blades, preventing contact and enhancing operational precision and durability, while allowing for consistent and reliable manufacturing processes.
Smart Images
Figure IB2024054946_28112024_PF_FP_ABST
Abstract
Description
[0001] Watch component with separate crossed blades and its manufacturing process
[0002] The present invention relates to a watch component with separate crossed blades such as an oscillator, a rocker or a support for an oscillator or rocker, for example.
[0003] Separate cross blades are a particularly popular type of flexible pivot that guides a movable part in rotation about a virtual axis of rotation relative to a base intended to be fixed to a frame. Separate cross blades connect the movable part to the base by extending in two parallel planes and in different directions to cross without contact.
[0004] One difficulty encountered when manufacturing a component with separate crossed blades is ensuring that the blades are spaced sufficiently apart in height so that they do not touch each other during operation of the component, particularly when the user's wrist is moving. Contact between the two blades can indeed result in a reduction in the accuracy of the watch. In addition, shocks received by the watch can cause the blades to collide and cause damage.
[0005] Patent application WO 2021 / 186333 of the present applicant proposes, in the case of a component with separate crossed silicon blades, to increase the spacing of the blades by subjecting them to several oxidation-deoxidation sequences. This solution is effective but it results in a modification of the dimensions of the blades, an effect which must be anticipated in the calculations and which complicates the theoretical study of the component. In addition, the spacings that can be achieved with this solution are quite small (of the order of ten micrometers). Another disadvantage is the length of the process, the number of oxidation-deoxidation sequences required being proportional to the desired increase in spacing of the blades. Another solution is described in patent application WO 2022 / 009102 of the present applicant.It consists of producing the component with separate crossed blades in the form of an assembly of two superimposed parts, each comprising one of the blades, a stage of the base and a stage of the moving part, and separating these two parts in height by two metal spacers in the base and the moving part respectively, the spacer of the moving part being constituted by a diametrical arm of a balance. The disadvantage of this solution is that due to manufacturing tolerances, it is difficult to obtain spacers that have the same height in the base and in the moving part. However, any difference in height between the blade embeddings adds constraints in the latter which can affect the precision of the operation of the component and, in the case of an oscillator, cause chronometric dispersions in terms in particular of absolute rate, isochronism or rate deviation at the positions.
[0006] The present invention aims to remedy, at least in part, the aforementioned drawbacks.
[0007] To this end, the present invention relates to a watch component with separate crossed blades comprising an assembly of a first part and a second part superimposed, the first part comprising first and second rigid parts connected by a first elastic blade, the second part comprising third and fourth rigid parts connected by a second elastic blade, the first and third rigid parts being integral, the second and fourth rigid parts being integral, the first and second elastic blades extending in parallel planes and in different directions to cross without contact, a first spacer integral with or forming part of the first rigid part and a second spacer integral with or forming part of the second rigid part ensuring a height separation of the first and second elastic blades,characterized in that the first and second spacers are produced by etching the same substrate. According to a particular embodiment of the invention, the first part comprises a first silicon layer, a second silicon dioxide layer and a third silicon layer produced by etching an SOI substrate, the first layer defining a first stage of the first rigid part, a first stage of the second rigid part and the first elastic blade, the second layer defining only a second stage of the first rigid part and a second stage of the second rigid part, the third layer defining only a third stage of the first rigid part and a third stage of the second rigid part, the second and third layers together forming the first and second spacers.,
[0008] Preferably, the second part comprises a fourth silicon layer, a fifth silicon dioxide layer and a sixth silicon layer resulting from the etching of an SOI substrate, the fourth layer defining only a first stage of the third rigid part and a first stage of the fourth rigid part, the fifth layer defining only a second stage of the third rigid part and a second stage of the fourth rigid part, the sixth layer defining a third stage of the third rigid part, a third stage of the fourth rigid part and the second elastic blade, the fourth and fifth layers serving as spacers ensuring a height spacing of the first and second elastic blades.
[0009] According to another embodiment of the invention, the first and second spacers are parts assembled between the first and second parts.
[0010] The present invention also relates to a watch oscillator comprising a watch component as defined above, in particular a watch oscillator comprising an assembly of such a watch component and a balance wheel.
[0011] The present invention also relates to a method for manufacturing a watch component with separate crossed blades comprising a step of assembling a first part and a second part superimposed, the first part comprising first and second rigid parts connected by a first elastic blade, the second part comprising third and fourth rigid parts connected by a second elastic blade, the assembly being carried out in such a way that the first and third rigid parts are integral, that the second and fourth rigid parts are integral,that the first and second elastic blades extend in parallel planes and in different directions to cross without contact and that a height separation of the first and second elastic blades is ensured by a first spacer integral with or forming part of the first rigid part and by a second spacer integral with or forming part of the second rigid part, characterized in that the first and second spacers are produced, before the assembly step, by etching the same substrate.,
[0012] According to a particular embodiment, the method comprises, before the assembly step, a step of producing the first part by etching a first SOI substrate constituting said same substrate, the first part obtained at the end of this production step comprises a first silicon layer, a second silicon dioxide layer and a third silicon layer originating from the first SOI substrate, the first layer defining a first stage of the first rigid part, a first stage of the second rigid part and the first elastic blade, the second layer defining only a second stage of the first rigid part and a second stage of the second rigid part, the third layer defining only a third stage of the first rigid part and a third stage of the second rigid part, and the second and third layers together form the first and second spacers.
[0013] Preferably, the method according to the invention further comprises, before the assembly step, a step of producing the second part by etching a second SOI substrate, the second part obtained at the end of this production step comprising a fourth silicon layer, a fifth silicon dioxide layer and a sixth silicon layer originating from the second SOI substrate, the fourth layer defining only a first stage of the third rigid part and a first stage of the fourth rigid part, the fifth layer defining only a second stage of the third rigid part and a second stage of the fourth rigid part, the sixth layer defining a third stage of the third rigid part, a third stage of the fourth rigid part and the second elastic blade,the fourth and fifth layers serving as spacers ensuring a height spacing of the first and second elastic blades after the assembly step. The first and second SOI substrates may be two different substrates or a single SOI substrate.,
[0014] According to another embodiment, during the assembly step the first and second spacers are assembled between the first and second parts.
[0015] Other characteristics and advantages of the present invention will appear on reading the following detailed description made with reference to the appended drawings in which:
[0016] - figure 1 is a plan view from above of a watch component according to a particular embodiment of the invention;
[0017] - figure 2 is a perspective view of the watch component illustrated in figure 1;
[0018] - figure 3 is an exploded perspective view of the watch component illustrated in figure 1;
[0019] - Figure 4 is a perspective view of a clock oscillator comprising the component illustrated in Figures 1 to 3;
[0020] - Figure 5 is a schematic side view of an SOI type substrate used to manufacture the watch component illustrated in Figures 1 to 3;
[0021] - Figure 6 is an exploded perspective view of a watch component according to another embodiment of the invention. In all that follows, the terms “first”, “second”, “third”, etc., serve only to distinguish the different parts or parts concerned without introducing any limitation with regard to the order or the manner in which these parts or parts are arranged.
[0022] With reference to Figures 1 to 4, a watch component 1 according to a particular embodiment of the invention, intended to serve as a flexible guide support for a balance wheel 2, is formed from an assembly of a first part 3 and a second part 4 superimposed. The first part 3 comprises first and second rigid parts 5, 6 connected by a first elastic blade 7. The second part 4 comprises third and fourth rigid parts 8, 9 connected by a second elastic blade 10. By the term "rigid" is meant that the parts 5, 6, 8, 9 do not deform substantially during the operation of the component 1.
[0023] The first and third rigid parts 5, 8 are in contact with each other and are made integral with each other by pins 11 clamped in elastic assembly ferrules 12, 13 of the rigid parts 5, 8 or by any other suitable assembly means or technique, such as soldering or fusion bonding. The first and third rigid parts 5, 8 together form a base of the watch component 1 intended to be fixed, for example by means of a screw passing through two aligned holes 14, 15 of the rigid parts 5, 8, in a fixed or mobile frame of a watch mechanism.
[0024] The second and fourth rigid parts 6, 9 are in contact with each other and are made integral with each other by pins 16 clamped in elastic assembly ferrules 17, 18 of the rigid parts 6, 9 or by any other suitable assembly means or technique, such as soldering or fusion bonding. The second and fourth rigid parts 6, 9 together form a movable part of the watch component 1 suspended from the base 5, 8 by the first and second elastic blades 7, 10 and guided in rotation relative to the base 5, 8 by these same elastic blades 7, 10 around a virtual axis of rotation A.
[0025] The first and second elastic blades 7, 10 extend in two different parallel planes and in two different directions to cross in top / bottom view. The crossing of the elastic blades 7, 10 at rest defines the virtual axis of rotation A, which is perpendicular to said parallel planes. In addition to suspending and guiding in rotation the movable part 6, 9, the first and second elastic blades 7, 10 exert on the movable part 6, 9 an elastic restoring torque tending to bring it back into an equilibrium position relative to the base 5, 8.
[0026] According to the invention, each of the first and second parts 3, 4 is a multilayer monobloc part resulting from the etching of a SOI (Silicon On Insulator) type substrate comprising a first silicon layer, a second silicon layer and an intermediate silicon dioxide layer binding the first and second silicon layers. Figure 5 illustrates such a substrate, 20, with the silicon layers designated by 21 and 22 and the intermediate silicon dioxide layer designated by 23.
[0027] More specifically, the first part 3 comprises a first layer 24 of silicon, a second layer 25 of silicon dioxide and a third layer 26 of silicon originating from an SOI substrate. The first layer 24 defines a first stage of the first rigid part 5, a first stage of the second rigid part 6 and the first elastic blade 7 connecting these two stages. The second layer 25, represented by a line in FIGS. 2 and 3 and located between the first and third layers 24, 26, defines only a second stage of the first rigid part 5 and a second stage of the second rigid part 6. The third layer 26 defines only a third stage of the first rigid part 5 and a third stage of the second rigid part 6.
[0028] The second part 4 comprises a fourth layer 27 of silicon, a fifth layer 28 of silicon dioxide and a sixth layer 29 of silicon from an SOI substrate. The fourth layer 27 is in contact with the third layer 26 and defines only a first stage of the third rigid part 8 and a first stage of the fourth rigid part 9. The fifth layer 28, represented by a line in Figures 2 and 3 and located between the fourth and sixth layers 27, 29, defines only a second stage of the third rigid part 8 and a second stage of the fourth rigid part 9. The sixth layer 29 defines a third stage of the third rigid part 8, a third stage of the fourth rigid part 9 and the second elastic blade 10 connecting these third stages.
[0029] Thus, the first elastic blade 7 is present only in the first layer 24 and the second elastic blade 10 is present only in the sixth layer 29, the second to fifth layers 25-28 serving as spacers separating in height (i.e. parallel to the virtual axis of rotation A) the elastic blades 7, 10 by a sufficient distance so that they cannot touch each other during the operation of the component 1 or during shocks or accelerations received by the latter. More precisely, the part 25a, 26a of the second and third layers 25, 26 located in the first rigid part 5 forms a first spacer at one embedding of the elastic blades 7, 10 while the part 25b, 26b of the second and third layers 25, 26 located in the second rigid part 6 forms a second spacer at the other embedding of the elastic blades 7, 10.Likewise, the part 27a, 28a of the fourth and fifth layers 27, 28 located in the third rigid part 8 forms a third spacer at one embedding of the elastic blades 7, 10 while the part 27b, 28b of the fourth and fifth layers 27, 28 located in the fourth rigid part 9 forms a fourth spacer at the other embedding of the elastic blades 7, 10.
[0030] As the second and third layers 25, 26, respectively the fourth and fifth layers 27, 28, forming spacers are produced with the elastic blade 7, respectively with the elastic blade 10, from an SOI substrate, their thickness is identical on the side of the base 5, 8 and on the side of the mobile part 6, 9 so that the two embeddings of each elastic blade 7, 10 are at the same height and do not cause deformation of the blade parallel to the virtual axis of rotation A. In this way, the separation of the elastic blades 7, 10 by spacers is prevented from deteriorating the operating precision of the component 1.
[0031] The manufacture of the watch component 1 can be particularly precise. An SOI substrate such as the substrate 20 illustrated in FIG. 5 can be etched on both of its silicon faces by DRIE (deep reactive ion etching) throughout the depth of the silicon layers 21 and 22 to form the first and third layers 24, 26 or the fourth and sixth layers 27, 29 of the component 1, until the etching is stopped by the intermediate silicon dioxide layer 23. Dipping the substrate in a hydrofluoric acid (HF) bath then removes the intermediate silicon dioxide layer 23 wherever it is not protected between two silicon layers, to form the second or fifth layer 25, 28 of the component 1. These DRIE and wet etching techniques are well mastered and precise.
[0032] The SOI substrate may be the same for both parts 3, 4. Thus, both parts 3, 4 may be etched simultaneously, one next to the other, in the same SOI substrate, either through different masks or through identical masks. In the latter case, one of the two parts 3, 4 is turned over after its detachment from the substrate for its assembly with the other part. Alternatively, both parts 3, 4 may be etched in different SOI substrates and then be assembled after their detachment from their respective substrates.
[0033] In another variant of the invention, only one of the two parts 3, 4 is multi-layer, the other part being produced by etching a single-layer silicon substrate and therefore not having a spacer. The second to fifth layers 25-28 can be hollowed out on the side of the mobile part 6, 9, in areas 30, to lighten the mobile part 6, 9 and / or improve its aerodynamics.
[0034] The component 1 may comprise in its mobile part 6, 9 an interaction element 31 intended to cooperate with another mobile component of the watch mechanism. In the example shown, this interaction element 31 is a radial impulse element fulfilling the function of a roller pin and intended to cooperate with an escapement anchor. The interaction element 31 is preferably defined by the second and third layers 25, 26 forming spacers, as shown, or by the fourth and fifth layers 27, 28 forming spacers, or partly by the second and third layers 25, 26 and partly by the fourth and fifth layers 27, 28, that is to say is preferably located between the two parallel planes in which the elastic blades 7, 10 extend. This makes it possible not to introduce a lever arm likely to cause the mobile part 6, 9 to rock when the interaction element 31 cooperates with the partner component.Compared to an interaction element which would be defined by a spacer assembled between the first and second parts 3, 4, the connection between the interaction element 31 and the elastic blades 7, 10 is very rigid, since there is no play or tightening to manage at the spacer.
[0035] Before their assembly, the first and second parts 3, 4 or only their elastic blades 7, 10 may be coated with a layer of silicon dioxide fulfilling a function of mechanical reinforcement and / or compensation for the variation in the stiffness of the elastic blades 7, 10 as a function of the temperature. More generally, the first and second parts 3, 4 may carry any suitable coating.
[0036] The height spacing of the elastic blades 7, 10 obtained with the second to fifth layers 25-28 is typically at least 50 pm, preferably at least 100 pm, preferably at least 150 pm, preferably at least 200 pm, preferably at least 250 pm, preferably at least 300 pm.
[0037] Figure 4 shows a clockwork oscillator comprising a balance 2 assembled to, and supported by, the moving part 6, 9 of the component 1. The term "balance" means any oscillating member, whatever its shape, allowing in association with an elastic return member (here, the elastic blades 7, 10) to serve as a time base. Because it is attached, the balance 2 can be made of a denser material than that of the component 1 for a better quality factor and / or to reduce the size in the oscillation plane. An oscillator could however be manufactured according to the invention with a single-piece balance with the second or fourth rigid part 6, 9 (i.e. engraved with it).
[0038] In the case of a clock oscillator, making the spacer in the form of the second to fifth layers 25-28 allows the chronometric precision not to be degraded.
[0039] The watch component 1 could serve as a flexible guide support for components other than a balance wheel, for example a rocker, or could itself be a component fulfilling, by its mobile part 6, 9 guided in rotation, the function of a rocker, a lever, a rack, a finger or other.
[0040] A watch component with separate crossed blades T according to another embodiment of the invention, capable of fulfilling the same functions and being used in the same applications as the watch component 1, is illustrated in Figure 6. It comprises an assembly of a first part 3' and a second part 4' superimposed. The first and second parts 3', 4' are each in one piece, have the same shape as the parts 3, 4 of the previous figures but are in a single level. Thus, the first and second rigid parts 5', 6' of the first part 3' are made in the same thickness as the first elastic blade 7', for example by etching (DRIE or other) of a single-layer substrate or by etching one of the silicon layers of an SOI substrate and removing the other layers.Likewise, the third and fourth rigid parts 8', 9' of the second part 4' are produced in the same thickness as the second elastic blade 10', for example by etching (DRIE or other) of a single-layer substrate or by etching one of the silicon layers of an SOI substrate and elimination of the other layers.
[0041] The first and second parts 3', 4', therefore the elastic blades 7', 10', are separated in height by added parts forming first and second spacers 32, 33. The first spacer 32 is located between the first and third rigid parts 5', 8' and is integral with the latter. The second spacer 33 is located between the second and fourth rigid parts 6', 9' and is integral with the latter. The assembly of parts 3', 4', 32, 33 is assembled by pins 11', 16' clamped in elastic assembly ferrules 12', 13', 17', 18', 34, 35 of said parts 3', 4', 32, 33, but could be assembled in another way, for example by brazing or fusion welding.
[0042] The first and second parts 3', 4' are for example made of silicon, quartz, silicon carbide, glass, sapphire, ruby or diamond. They can be covered with a layer of another material, for example a layer of silicon dioxide when they are made of silicon. The first and second parts 3', 4' can also be made of metal or alloy, and produced for example by LIGA or electroerosion.
[0043] The first and second spacers 32, 33 are obtained by etching (DRIE or other) of the same substrate, through different masks, and can therefore be considered as having exactly the same thickness, which makes it possible not to deform the elastic blades 7', 10' in the height direction. The substrate can be single-layer or of the SOI type. In the second case, only one of the silicon layers is etched to form the spacers 32, 33 and the other layers are then eliminated. The first and second spacers 32, 33 are typically made of silicon, quartz, silicon carbide, glass, sapphire, ruby or diamond. They can be covered with a layer of another material, for example a layer of silicon dioxide when they are made of silicon. Their material can be the same as that of the first and second parts 3', 4' or can be different.
[0044] The watch component T could comprise more than one pair of added spacers, and could in particular comprise a second pair of spacers superimposed on the spacers 32, 33 and resulting from the etching of the same substrate which could be the one in which the spacers 32, 33 were etched or another substrate. It would also be possible to combine the embodiment of FIGS. 1 to 3 with that of FIG. 6, that is to say to have spacers formed with the elastic blades in an SOI substrate and, in addition, added spacers of the type of spacers 32, 33.
Claims
CLAIMS 1. A watch component with separate crossed blades (1; T) comprising an assembly of a first part (3; 3') and a second part (4; 4') superimposed, the first part (3; 3') comprising first and second rigid parts (5, 6; 5', 6') connected by a first elastic blade (7; 7'), the second part (4; 4') comprising third and fourth rigid parts (8, 9; 8', 9') connected by a second elastic blade (10; 10'), the first and third rigid parts (5, 8; 5', 8') being integral, the second and fourth rigid parts (6, 9; 6', 9') being integral, the first and second elastic blades (7, 10; 7', 10') extending in parallel planes and in different directions to cross without contact, a first spacer (25a, 26a; 32) integral with or forming part of the first rigid part (5; 5') and a second spacer (25b, 26b;33) integral with or forming part of the second rigid part (6) ensuring a height separation of the first and second elastic blades (7, 10; 7', 10'), characterized in that the first and second spacers (25a, 26a, 25b, 26b; 32, 33) are produced by etching the same substrate.; 2. Watch component according to claim 1, characterized in that the first part (3) comprises a first layer (24) of silicon, a second layer (25) of silicon dioxide and a third layer (26) of silicon resulting from the etching of an SOI substrate, the first layer (24) defining a first stage of the first rigid part (5), a first stage of the second rigid part (6) and the first elastic blade (7), the second layer (25) defining only a second stage of the first rigid part (5) and a second stage of the second rigid part (6), the third layer (26) defining only a third stage of the first rigid part (5) and a third stage of the second rigid part (6), and in that the second and third layers (25, 26) together form the first and second spacers (25a, 26a, 25b, 26b).
3. A timepiece component according to claim 2, characterized in that the second part (4) comprises a fourth layer (27) of silicon, a fifth layer (28) of silicon dioxide and a sixth layer (29) of silicon resulting from the etching of an SOI substrate, the fourth layer (27) defining only a first stage of the third rigid part (8) and a first stage of the fourth rigid part (9), the fifth layer (28) defining only a second stage of the third rigid part (8) and a second stage of the fourth rigid part (9), the sixth layer (29) defining a third stage of the third rigid part (8), a third stage of the fourth rigid part (9) and the second elastic blade (10), and in that the fourth and fifth layers (27, 28) serve as spacers (27a, 28a, 27b, 28b) ensuring a height spacing of the first and second elastic blades (7, 10).
4. Watch component according to claim 2 or 3, characterized in that it comprises an interaction element (31) intended to cooperate with a partner mobile component, and in that this interaction element (31) is defined at least in part by the second and third layers (25, 26).
5. Watch component according to claim 1, characterized in that the first and second spacers (32, 33) are parts assembled between the first and second parts (3', 4').
6. Watch component according to claim 5, characterized in that the first and second spacers (32, 33) are made of silicon, quartz, silicon carbide, glass, sapphire, ruby or diamond.
7. Watch component according to any one of claims 1 to 6, characterized in that the first and second parts (3, 4; 3', 4') are assembled by pins (11, 16; 11', 16').
8. Watch component according to any one of claims 1 to 6, characterized in that the first and second parts are assembled by brazing or by fusion welding.
9. Clock oscillator comprising a clock component (1; 1') according to any one of claims 1 to 8.
10. Clock oscillator according to claim 9, characterized in that it comprises a balance (2) assembled to the clock component (1; T). 11 . A method of manufacturing a watch component with separate crossed blades (1; T) comprising a step of assembling a first part (3; 3') and a second part (4; 4') superimposed, the first part (3; 3') comprising first and second rigid parts (5, 6; 5', 6') connected by a first elastic blade (7; 7'), the second part (4; 4') comprising third and fourth rigid parts (8, 9; 8', 9') connected by a second elastic blade (10; 10'), the assembly being carried out in such a way that the first and third rigid parts (5, 8; 5', 8') are integral, that the second and fourth rigid parts (6, 9; 6', 9') are integral, that the first and second elastic blades (7, 10; 7', 10') extend in parallel planes and in different directions for cross without contact and that a height spacing of the first and second elastic blades (7, 10; 7', 10') is ensured by a first spacer (25a, 26a; 32) integral with or forming part of the first rigid part (5; 5') and by a second spacer (25b, 26b; 33) integral with or forming part of the second rigid part (6; 6'), characterized in that the first and second spacers (25a, 26a, 25b, 26b; 32, 33) are produced, before the assembly step, by etching the same substrate.
12. Method according to claim 11, characterized in that it comprises, before the assembly step, a step of producing the first part (3) by etching a first SOI substrate constituting said same substrate, in that the first part (3) obtained at the end of this production step comprises a first layer (24) of silicon, a second layer (25) of silicon dioxide and a third layer (26) of silicon originating from the first SOI substrate, the first layer (24) defining a first stage of the first rigid part (5), a first stage of the second rigid part (6) and the first elastic blade (7), the second layer (25) defining only a second stage of the first rigid part (5) and a second stage of the second rigid part (6), the third layer (26) defining only a third stage of the first rigid part (5) and a third stage of the second rigid part (6),and in that the second and third layers (25, 26) together form the first and second spacers (25a, 26a, 25b, 26b)., 13. Method according to claim 12, characterized in that it comprises, before the assembly step, a step of producing the second part (4) by etching a second SOI substrate, in that the second part (4) obtained at the end of this production step comprises a fourth layer (27) of silicon, a fifth layer (28) of silicon dioxide and a sixth layer (29) of silicon from the second SOI substrate, the fourth layer (27) defining only a first stage of the third rigid part (8) and a first stage of the fourth rigid part (9), the fifth layer (28) defining only a second stage of the third rigid part (8) and a second stage of the fourth rigid part (9), the sixth layer (29) defining a third stage of the third rigid part (8), a third stage of the fourth rigid part (9) and the second elastic blade (10), and in that the fourth and fifth layers (27, 28) serve as spacers (27a, 28a, 27b, 28b) ensuring a height spacing of the first and second elastic blades (7, 10) after the assembly step.
14. Method according to claim 13, characterized in that the first and second SOI substrates are a single SOI substrate.
15. Method according to claim 11, characterized in that during the assembly step the first and second spacers (32, 33) are assembled between the first and second parts (3', 4').
16. Method according to claim 15, characterized in that the first and second spacers (32, 33) are made of silicon, quartz, silicon carbide, glass, sapphire, ruby or diamond.
17. Method according to any one of claims 11 to 16, characterized in that the assembly of the first and second parts (3, 4; 3', 4') is carried out by means of pins (11, 16; 11', 16').
18. Method according to any one of claims 11 to 16, characterized in that the assembly of the first and second parts is carried out by brazing or by fusion welding.
19. Method according to any one of claims 11 to 18, characterized in that the watch component is an oscillator.